diff options
| -rw-r--r-- | drivers/clk/clk-scmi.c | 22 | ||||
| -rw-r--r-- | drivers/cpufreq/scmi-cpufreq.c | 3 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/Makefile | 4 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/base.c | 108 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/clock.c | 20 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/common.h | 4 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 15 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/notify.c | 1526 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/notify.h | 68 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/perf.c | 151 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/power.c | 92 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/reset.c | 96 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/scmi_pm_domain.c | 12 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/sensors.c | 69 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/smc.c | 1 | ||||
| -rw-r--r-- | include/linux/scmi_protocol.h | 110 | ||||
| -rw-r--r-- | include/trace/events/scmi.h | 6 |
17 files changed, 2258 insertions, 49 deletions
diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c index c491f5de0f3f..c754dfbb73fd 100644 --- a/drivers/clk/clk-scmi.c +++ b/drivers/clk/clk-scmi.c @@ -103,6 +103,8 @@ static const struct clk_ops scmi_clk_ops = { static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk) { int ret; + unsigned long min_rate, max_rate; + struct clk_init_data init = { .flags = CLK_GET_RATE_NOCACHE, .num_parents = 0, @@ -112,9 +114,23 @@ static int scmi_clk_ops_init(struct device *dev, struct scmi_clk *sclk) sclk->hw.init = &init; ret = devm_clk_hw_register(dev, &sclk->hw); - if (!ret) - clk_hw_set_rate_range(&sclk->hw, sclk->info->range.min_rate, - sclk->info->range.max_rate); + if (ret) + return ret; + + if (sclk->info->rate_discrete) { + int num_rates = sclk->info->list.num_rates; + + if (num_rates <= 0) + return -EINVAL; + + min_rate = sclk->info->list.rates[0]; + max_rate = sclk->info->list.rates[num_rates - 1]; + } else { + min_rate = sclk->info->range.min_rate; + max_rate = sclk->info->range.max_rate; + } + + clk_hw_set_rate_range(&sclk->hw, min_rate, max_rate); return ret; } diff --git a/drivers/cpufreq/scmi-cpufreq.c b/drivers/cpufreq/scmi-cpufreq.c index 61623e2ff149..1cf688fcb56b 100644 --- a/drivers/cpufreq/scmi-cpufreq.c +++ b/drivers/cpufreq/scmi-cpufreq.c @@ -198,7 +198,8 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy) policy->cpuinfo.transition_latency = latency; - policy->fast_switch_possible = true; + policy->fast_switch_possible = + handle->perf_ops->fast_switch_possible(handle, cpu_dev); em_register_perf_domain(policy->cpus, nr_opp, &em_cb); diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index 1cad32b38b29..6f9cbc4aef22 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -1,9 +1,9 @@ # SPDX-License-Identifier: GPL-2.0-only obj-y = scmi-bus.o scmi-driver.o scmi-protocols.o scmi-transport.o scmi-bus-y = bus.o -scmi-driver-y = driver.o +scmi-driver-y = driver.o notify.o scmi-transport-y = shmem.o scmi-transport-$(CONFIG_MAILBOX) += mailbox.o -scmi-transport-$(CONFIG_ARM_PSCI_FW) += smc.o +scmi-transport-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smc.o scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o obj-$(CONFIG_ARM_SCMI_POWER_DOMAIN) += scmi_pm_domain.o diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c index ce7d9203e41b..9853bd3c4d45 100644 --- a/drivers/firmware/arm_scmi/base.c +++ b/drivers/firmware/arm_scmi/base.c @@ -5,7 +5,15 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications BASE - " fmt + +#include <linux/scmi_protocol.h> + #include "common.h" +#include "notify.h" + +#define SCMI_BASE_NUM_SOURCES 1 +#define SCMI_BASE_MAX_CMD_ERR_COUNT 1024 enum scmi_base_protocol_cmd { BASE_DISCOVER_VENDOR = 0x3, @@ -19,16 +27,25 @@ enum scmi_base_protocol_cmd { BASE_RESET_AGENT_CONFIGURATION = 0xb, }; -enum scmi_base_protocol_notify { - BASE_ERROR_EVENT = 0x0, -}; - struct scmi_msg_resp_base_attributes { u8 num_protocols; u8 num_agents; __le16 reserved; }; +struct scmi_msg_base_error_notify { + __le32 event_control; +#define BASE_TP_NOTIFY_ALL BIT(0) +}; + +struct scmi_base_error_notify_payld { + __le32 agent_id; + __le32 error_status; +#define IS_FATAL_ERROR(x) ((x) & BIT(31)) +#define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x)) + __le64 msg_reports[SCMI_BASE_MAX_CMD_ERR_COUNT]; +}; + /** * scmi_base_attributes_get() - gets the implementation details * that are associated with the base protocol. @@ -222,6 +239,83 @@ static int scmi_base_discover_agent_get(const struct scmi_handle *handle, return ret; } +static int scmi_base_error_notify(const struct scmi_handle *handle, bool enable) +{ + int ret; + u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0; + struct scmi_xfer *t; + struct scmi_msg_base_error_notify *cfg; + + ret = scmi_xfer_get_init(handle, BASE_NOTIFY_ERRORS, + SCMI_PROTOCOL_BASE, sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->event_control = cpu_to_le32(evt_cntl); + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_base_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_base_error_notify(handle, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] ret:%d\n", evt_id, ret); + + return ret; +} + +static void *scmi_base_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + int i; + const struct scmi_base_error_notify_payld *p = payld; + struct scmi_base_error_report *r = report; + + /* + * BaseError notification payload is variable in size but + * up to a maximum length determined by the struct ponted by p. + * Instead payld_sz is the effective length of this notification + * payload so cannot be greater of the maximum allowed size as + * pointed by p. + */ + if (evt_id != SCMI_EVENT_BASE_ERROR_EVENT || sizeof(*p) < payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status)); + r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status)); + for (i = 0; i < r->cmd_count; i++) + r->reports[i] = le64_to_cpu(p->msg_reports[i]); + *src_id = 0; + + return r; +} + +static const struct scmi_event base_events[] = { + { + .id = SCMI_EVENT_BASE_ERROR_EVENT, + .max_payld_sz = sizeof(struct scmi_base_error_notify_payld), + .max_report_sz = sizeof(struct scmi_base_error_report) + + SCMI_BASE_MAX_CMD_ERR_COUNT * sizeof(u64), + }, +}; + +static const struct scmi_event_ops base_event_ops = { + .set_notify_enabled = scmi_base_set_notify_enabled, + .fill_custom_report = scmi_base_fill_custom_report, +}; + int scmi_base_protocol_init(struct scmi_handle *h) { int id, ret; @@ -256,6 +350,12 @@ int scmi_base_protocol_init(struct scmi_handle *h) dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols, rev->num_agents); + scmi_register_protocol_events(handle, SCMI_PROTOCOL_BASE, + (4 * SCMI_PROTO_QUEUE_SZ), + &base_event_ops, base_events, + ARRAY_SIZE(base_events), + SCMI_BASE_NUM_SOURCES); + for (id = 0; id < rev->num_agents; id++) { scmi_base_discover_agent_get(handle, id, name); dev_dbg(dev, "Agent %d: %s\n", id, name); diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c index 4c2227662b26..6593ce87f420 100644 --- a/drivers/firmware/arm_scmi/clock.c +++ b/drivers/firmware/arm_scmi/clock.c @@ -5,6 +5,8 @@ * Copyright (C) 2018 ARM Ltd. */ +#include <linux/sort.h> + #include "common.h" enum scmi_clock_protocol_cmd { @@ -121,11 +123,23 @@ static int scmi_clock_attributes_get(const struct scmi_handle *handle, return ret; } +static int rate_cmp_func(const void *_r1, const void *_r2) +{ + const u64 *r1 = _r1, *r2 = _r2; + + if (*r1 < *r2) + return -1; + else if (*r1 == *r2) + return 0; + else + return 1; +} + static int scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id, struct scmi_clock_info *clk) { - u64 *rate; + u64 *rate = 0; int ret, cnt; bool rate_discrete = false; u32 tot_rate_cnt = 0, rates_flag; @@ -184,8 +198,10 @@ scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id, */ } while (num_returned && num_remaining); - if (rate_discrete) + if (rate_discrete && rate) { clk->list.num_rates = tot_rate_cnt; + sort(rate, tot_rate_cnt, sizeof(*rate), rate_cmp_func, NULL); + } clk->rate_discrete = rate_discrete; diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 31fe5a22a011..c113e578cc6c 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -6,6 +6,8 @@ * * Copyright (C) 2018 ARM Ltd. */ +#ifndef _SCMI_COMMON_H +#define _SCMI_COMMON_H #include <linux/bitfield.h> #include <linux/completion.h> @@ -235,3 +237,5 @@ void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem, void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem); bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem, struct scmi_xfer *xfer); + +#endif /* _SCMI_COMMON_H */ diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 7483cacf63f9..03ec74242c14 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -26,6 +26,7 @@ #include <linux/slab.h> #include "common.h" +#include "notify.h" #define CREATE_TRACE_POINTS #include <trace/events/scmi.h> @@ -208,7 +209,9 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) struct device *dev = cinfo->dev; struct scmi_info *info = handle_to_scmi_info(cinfo->handle); struct scmi_xfers_info *minfo = &info->rx_minfo; + ktime_t ts; + ts = ktime_get_boottime(); xfer = scmi_xfer_get(cinfo->handle, minfo); if (IS_ERR(xfer)) { dev_err(dev, "failed to get free message slot (%ld)\n", @@ -221,6 +224,8 @@ static void scmi_handle_notification(struct scmi_chan_info *cinfo, u32 msg_hdr) scmi_dump_header_dbg(dev, &xfer->hdr); info->desc->ops->fetch_notification(cinfo, info->desc->max_msg_size, xfer); + scmi_notify(cinfo->handle, xfer->hdr.protocol_id, + xfer->hdr.id, xfer->rx.buf, xfer->rx.len, ts); trace_scmi_rx_done(xfer->transfer_id, xfer->hdr.id, xfer->hdr.protocol_id, xfer->hdr.seq, @@ -392,8 +397,7 @@ int scmi_do_xfer(const struct scmi_handle *handle, struct scmi_xfer *xfer) info->desc->ops->mark_txdone(cinfo, ret); trace_scmi_xfer_end(xfer->transfer_id, xfer->hdr.id, - xfer->hdr.protocol_id, xfer->hdr.seq, - xfer->hdr.status); + xfer->hdr.protocol_id, xfer->hdr.seq, ret); return ret; } @@ -789,6 +793,9 @@ static int scmi_probe(struct platform_device *pdev) if (ret) return ret; + if (scmi_notification_init(handle)) + dev_err(dev, "SCMI Notifications NOT available.\n"); + ret = scmi_base_protocol_init(handle); if (ret) { dev_err(dev, "unable to communicate with SCMI(%d)\n", ret); @@ -831,6 +838,8 @@ static int scmi_remove(struct platform_device *pdev) struct scmi_info *info = platform_get_drvdata(pdev); struct idr *idr = &info->tx_idr; + scmi_notification_exit(&info->handle); + mutex_lock(&scmi_list_mutex); if (info->users) ret = -EBUSY; @@ -901,7 +910,7 @@ ATTRIBUTE_GROUPS(versions); /* Each compatible listed below must have descriptor associated with it */ static const struct of_device_id scmi_of_match[] = { { .compatible = "arm,scmi", .data = &scmi_mailbox_desc }, -#ifdef CONFIG_ARM_PSCI_FW +#ifdef CONFIG_HAVE_ARM_SMCCC_DISCOVERY { .compatible = "arm,scmi-smc", .data = &scmi_smc_desc}, #endif { /* Sentinel */ }, diff --git a/drivers/firmware/arm_scmi/notify.c b/drivers/firmware/arm_scmi/notify.c new file mode 100644 index 000000000000..4731daaacd19 --- /dev/null +++ b/drivers/firmware/arm_scmi/notify.c @@ -0,0 +1,1526 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Notification support + * + * Copyright (C) 2020 ARM Ltd. + */ +/** + * DOC: Theory of operation + * + * SCMI Protocol specification allows the platform to signal events to + * interested agents via notification messages: this is an implementation + * of the dispatch and delivery of such notifications to the interested users + * inside the Linux kernel. + * + * An SCMI Notification core instance is initialized for each active platform + * instance identified by the means of the usual &struct scmi_handle. + * + * Each SCMI Protocol implementation, during its initialization, registers with + * this core its set of supported events using scmi_register_protocol_events(): + * all the needed descriptors are stored in the &struct registered_protocols and + * &struct registered_events arrays. + * + * Kernel users interested in some specific event can register their callbacks + * providing the usual notifier_block descriptor, since this core implements + * events' delivery using the standard Kernel notification chains machinery. + * + * Given the number of possible events defined by SCMI and the extensibility + * of the SCMI Protocol itself, the underlying notification chains are created + * and destroyed dynamically on demand depending on the number of users + * effectively registered for an event, so that no support structures or chains + * are allocated until at least one user has registered a notifier_block for + * such event. Similarly, events' generation itself is enabled at the platform + * level only after at least one user has registered, and it is shutdown after + * the last user for that event has gone. + * + * All users provided callbacks and allocated notification-chains are stored in + * the @registered_events_handlers hashtable. Callbacks' registration requests + * for still to be registered events are instead kept in the dedicated common + * hashtable @pending_events_handlers. + * + * An event is identified univocally by the tuple (proto_id, evt_id, src_id) + * and is served by its own dedicated notification chain; information contained + * in such tuples is used, in a few different ways, to generate the needed + * hash-keys. + * + * Here proto_id and evt_id are simply the protocol_id and message_id numbers + * as described in the SCMI Protocol specification, while src_id represents an + * optional, protocol dependent, source identifier (like domain_id, perf_id + * or sensor_id and so forth). + * + * Upon reception of a notification message from the platform the SCMI RX ISR + * passes the received message payload and some ancillary information (including + * an arrival timestamp in nanoseconds) to the core via @scmi_notify() which + * pushes the event-data itself on a protocol-dedicated kfifo queue for further + * deferred processing as specified in @scmi_events_dispatcher(). + * + * Each protocol has it own dedicated work_struct and worker which, once kicked + * by the ISR, takes care to empty its own dedicated queue, deliverying the + * queued items into the proper notification-chain: notifications processing can + * proceed concurrently on distinct workers only between events belonging to + * different protocols while delivery of events within the same protocol is + * still strictly sequentially ordered by time of arrival. + * + * Events' information is then extracted from the SCMI Notification messages and + * conveyed, converted into a custom per-event report struct, as the void *data + * param to the user callback provided by the registered notifier_block, so that + * from the user perspective his callback will look invoked like: + * + * int user_cb(struct notifier_block *nb, unsigned long event_id, void *report) + * + */ + +#define dev_fmt(fmt) "SCMI Notifications - " fmt +#define pr_fmt(fmt) "SCMI Notifications - " fmt + +#include <linux/bitfield.h> +#include <linux/bug.h> +#include <linux/compiler.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/hashtable.h> +#include <linux/kernel.h> +#include <linux/ktime.h> +#include <linux/kfifo.h> +#include <linux/list.h> +#include <linux/mutex.h> +#include <linux/notifier.h> +#include <linux/refcount.h> +#include <linux/scmi_protocol.h> +#include <linux/slab.h> +#include <linux/types.h> +#include <linux/workqueue.h> + +#include "notify.h" + +#define SCMI_MAX_PROTO 256 + +#define PROTO_ID_MASK GENMASK(31, 24) +#define EVT_ID_MASK GENMASK(23, 16) +#define SRC_ID_MASK GENMASK(15, 0) + +/* + * Builds an unsigned 32bit key from the given input tuple to be used + * as a key in hashtables. + */ +#define MAKE_HASH_KEY(p, e, s) \ + (FIELD_PREP(PROTO_ID_MASK, (p)) | \ + FIELD_PREP(EVT_ID_MASK, (e)) | \ + FIELD_PREP(SRC_ID_MASK, (s))) + +#define MAKE_ALL_SRCS_KEY(p, e) MAKE_HASH_KEY((p), (e), SRC_ID_MASK) + +/* + * Assumes that the stored obj includes its own hash-key in a field named 'key': + * with this simplification this macro can be equally used for all the objects' + * types hashed by this implementation. + * + * @__ht: The hashtable name + * @__obj: A pointer to the object type to be retrieved from the hashtable; + * it will be used as a cursor while scanning the hastable and it will + * be possibly left as NULL when @__k is not found + * @__k: The key to search for + */ +#define KEY_FIND(__ht, __obj, __k) \ +({ \ + typeof(__k) k_ = __k; \ + typeof(__obj) obj_; \ + \ + hash_for_each_possible((__ht), obj_, hash, k_) \ + if (obj_->key == k_) \ + break; \ + __obj = obj_; \ +}) + +#define KEY_XTRACT_PROTO_ID(key) FIELD_GET(PROTO_ID_MASK, (key)) +#define KEY_XTRACT_EVT_ID(key) FIELD_GET(EVT_ID_MASK, (key)) +#define KEY_XTRACT_SRC_ID(key) FIELD_GET(SRC_ID_MASK, (key)) + +/* + * A set of macros used to access safely @registered_protocols and + * @registered_events arrays; these are fixed in size and each entry is possibly + * populated at protocols' registration time and then only read but NEVER + * modified or removed. + */ +#define SCMI_GET_PROTO(__ni, __pid) \ +({ \ + typeof(__ni) ni_ = __ni; \ + struct scmi_registered_events_desc *__pd = NULL; \ + \ + if (ni_) \ + __pd = READ_ONCE(ni_->registered_protocols[(__pid)]); \ + __pd; \ +}) + +#define SCMI_GET_REVT_FROM_PD(__pd, __eid) \ +({ \ + typeof(__pd) pd_ = __pd; \ + typeof(__eid) eid_ = __eid; \ + struct scmi_registered_event *__revt = NULL; \ + \ + if (pd_ && eid_ < pd_->num_events) \ + __revt = READ_ONCE(pd_->registered_events[eid_]); \ + __revt; \ +}) + +#define SCMI_GET_REVT(__ni, __pid, __eid) \ +({ \ + struct scmi_registered_event *__revt; \ + struct scmi_registered_events_desc *__pd; \ + \ + __pd = SCMI_GET_PROTO((__ni), (__pid)); \ + __revt = SCMI_GET_REVT_FROM_PD(__pd, (__eid)); \ + __revt; \ +}) + +/* A couple of utility macros to limit cruft when calling protocols' helpers */ +#define REVT_NOTIFY_SET_STATUS(revt, eid, sid, state) \ +({ \ + typeof(revt) r = revt; \ + r->proto->ops->set_notify_enabled(r->proto->ni->handle, \ + (eid), (sid), (state)); \ +}) + +#define REVT_NOTIFY_ENABLE(revt, eid, sid) \ + REVT_NOTIFY_SET_STATUS((revt), (eid), (sid), true) + +#define REVT_NOTIFY_DISABLE(revt, eid, sid) \ + REVT_NOTIFY_SET_STATUS((revt), (eid), (sid), false) + +#define REVT_FILL_REPORT(revt, ...) \ +({ \ + typeof(revt) r = revt; \ + r->proto->ops->fill_custom_report(r->proto->ni->handle, \ + __VA_ARGS__); \ +}) + +#define SCMI_PENDING_HASH_SZ 4 +#define SCMI_REGISTERED_HASH_SZ 6 + +struct scmi_registered_events_desc; + +/** + * struct scmi_notify_instance - Represents an instance of the notification + * core + * @gid: GroupID used for devres + * @handle: A reference to the platform instance + * @init_work: A work item to perform final initializations of pending handlers + * @notify_wq: A reference to the allocated Kernel cmwq + * @pending_mtx: A mutex to protect @pending_events_handlers + * @registered_protocols: A statically allocated array containing pointers to + * all the registered protocol-level specific information + * related to events' handling + * @pending_events_handlers: An hashtable containing all pending events' + * handlers descriptors + * + * Each platform instance, represented by a handle, has its own instance of + * the notification subsystem represented by this structure. + */ +struct scmi_notify_instance { + void *gid; + struct scmi_handle *handle; + struct work_struct init_work; + struct workqueue_struct *notify_wq; + /* lock to protect pending_events_handlers */ + struct mutex pending_mtx; + struct scmi_registered_events_desc **registered_protocols; + DECLARE_HASHTABLE(pending_events_handlers, SCMI_PENDING_HASH_SZ); +}; + +/** + * struct events_queue - Describes a queue and its associated worker + * @sz: Size in bytes of the related kfifo + * @kfifo: A dedicated Kernel kfifo descriptor + * @notify_work: A custom work item bound to this queue + * @wq: A reference to the associated workqueue + * + * Each protocol has its own dedicated events_queue descriptor. + */ +struct events_queue { + size_t sz; + struct kfifo kfifo; + struct work_struct notify_work; + struct workqueue_struct *wq; +}; + +/** + * struct scmi_event_header - A utility header + * @timestamp: The timestamp, in nanoseconds (boottime), which was associated + * to this event as soon as it entered the SCMI RX ISR + * @payld_sz: Effective size of the embedded message payload which follows + * @evt_id: Event ID (corresponds to the Event MsgID for this Protocol) + * @payld: A reference to the embedded event payload + * + * This header is prepended to each received event message payload before + * queueing it on the related &struct events_queue. + */ +struct scmi_event_header { + ktime_t timestamp; + size_t payld_sz; + unsigned char evt_id; + unsigned char payld[]; +}; + +struct scmi_registered_event; + +/** + * struct scmi_registered_events_desc - Protocol Specific information + * @id: Protocol ID + * @ops: Protocol specific and event-related operations + * @equeue: The embedded per-protocol events_queue + * @ni: A reference to the initialized instance descriptor + * @eh: A reference to pre-allocated buffer to be used as a scratch area by the + * deferred worker when fetching data from the kfifo + * @eh_sz: Size of the pre-allocated buffer @eh + * @in_flight: A reference to an in flight &struct scmi_registered_event + * @num_events: Number of events in @registered_events + * @registered_events: A dynamically allocated array holding all the registered + * events' descriptors, whose fixed-size is determined at + * compile time. + * @registered_mtx: A mutex to protect @registered_events_handlers + * @registered_events_handlers: An hashtable containing all events' handlers + * descriptors registered for this protocol + * + * All protocols that register at least one event have their protocol-specific + * information stored here, together with the embedded allocated events_queue. + * These descriptors are stored in the @registered_protocols array at protocol + * registration time. + * + * Once these descriptors are successfully registered, they are NEVER again + * removed or modified since protocols do not unregister ever, so that, once + * we safely grab a NON-NULL reference from the array we can keep it and use it. + */ +struct scmi_registered_events_desc { + u8 id; + const struct scmi_event_ops *ops; + struct events_queue equeue; + struct scmi_notify_instance *ni; + struct scmi_event_header *eh; + size_t eh_sz; + void *in_flight; + int num_events; + struct scmi_registered_event **registered_events; + /* mutex to protect registered_events_handlers */ + struct mutex registered_mtx; + DECLARE_HASHTABLE(registered_events_handlers, SCMI_REGISTERED_HASH_SZ); +}; + +/** + * struct scmi_registered_event - Event Specific Information + * @proto: A reference to the associated protocol descriptor + * @evt: A reference to the associated event descriptor (as provided at + * registration time) + * @report: A pre-allocated buffer used by the deferred worker to fill a + * customized event report + * @num_sources: The number of possible sources for this event as stated at + * events' registration time + * @sources: A reference to a dynamically allocated array used to refcount the + * events' enable requests for all the existing sources + * @sources_mtx: A mutex to serialize the access to @sources + * + * All registered events are represented by one of these structures that are + * stored in the @registered_events array at protocol registration time. + * + * Once these descriptors are successfully registered, they are NEVER again + * removed or modified since protocols do not unregister ever, so that once we + * safely grab a NON-NULL reference from the table we can keep it and use it. + */ +struct scmi_registered_event { + struct scmi_registered_events_desc *proto; + const struct scmi_event *evt; + void *report; + u32 num_sources; + refcount_t *sources; + /* locking to serialize the access to sources */ + struct mutex sources_mtx; +}; + +/** + * struct scmi_event_handler - Event handler information + * @key: The used hashkey + * @users: A reference count for number of active users for this handler + * @r_evt: A reference to the associated registered event; when this is NULL + * this handler is pending, which means that identifies a set of + * callbacks intended to be attached to an event which is still not + * known nor registered by any protocol at that point in time + * @chain: The notification chain dedicated to this specific event tuple + * @hash: The hlist_node used for collision handling + * @enabled: A boolean which records if event's generation has been already + * enabled for this handler as a whole + * + * This structure collects all the information needed to process a received + * event identified by the tuple (proto_id, evt_id, src_id). + * These descriptors are stored in a per-protocol @registered_events_handlers + * table using as a key a value derived from that tuple. + */ +struct scmi_event_handler { + u32 key; + refcount_t users; + struct scmi_registered_event *r_evt; + struct blocking_notifier_head chain; + struct hlist_node hash; + bool enabled; +}; + +#define IS_HNDL_PENDING(hndl) (!(hndl)->r_evt) + +static struct scmi_event_handler * +scmi_get_active_handler(struct scmi_notify_instance *ni, u32 evt_key); +static void scmi_put_active_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl); +static void scmi_put_handler_unlocked(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl); + +/** + * scmi_lookup_and_call_event_chain() - Lookup the proper chain and call it + * @ni: A reference to the notification instance to use + * @evt_key: The key to use to lookup the related notification chain + * @report: The customized event-specific report to pass down to the callbacks + * as their *data parameter. + */ +static inline void +scmi_lookup_and_call_event_chain(struct scmi_notify_instance *ni, + u32 evt_key, void *report) +{ + int ret; + struct scmi_event_handler *hndl; + + /* + * Here ensure the event handler cannot vanish while using it. + * It is legitimate, though, for an handler not to be found at all here, + * e.g. when it has been unregistered by the user after some events had + * already been queued. + */ + hndl = scmi_get_active_handler(ni, evt_key); + if (!hndl) + return; + + ret = blocking_notifier_call_chain(&hndl->chain, + KEY_XTRACT_EVT_ID(evt_key), + report); + /* Notifiers are NOT supposed to cut the chain ... */ + WARN_ON_ONCE(ret & NOTIFY_STOP_MASK); + + scmi_put_active_handler(ni, hndl); +} + +/** + * scmi_process_event_header() - Dequeue and process an event header + * @eq: The queue to use + * @pd: The protocol descriptor to use + * + * Read an event header from the protocol queue into the dedicated scratch + * buffer and looks for a matching registered event; in case an anomalously + * sized read is detected just flush the queue. + * + * Return: + * * a reference to the matching registered event when found + * * ERR_PTR(-EINVAL) when NO registered event could be found + * * NULL when the queue is empty + */ +static inline struct scmi_registered_event * +scmi_process_event_header(struct events_queue *eq, + struct scmi_registered_events_desc *pd) +{ + unsigned int outs; + struct scmi_registered_event *r_evt; + + outs = kfifo_out(&eq->kfifo, pd->eh, + sizeof(struct scmi_event_header)); + if (!outs) + return NULL; + if (outs != sizeof(struct scmi_event_header)) { + dev_err(pd->ni->handle->dev, "corrupted EVT header. Flush.\n"); + kfifo_reset_out(&eq->kfifo); + return NULL; + } + + r_evt = SCMI_GET_REVT_FROM_PD(pd, pd->eh->evt_id); + if (!r_evt) + r_evt = ERR_PTR(-EINVAL); + + return r_evt; +} + +/** + * scmi_process_event_payload() - Dequeue and process an event payload + * @eq: The queue to use + * @pd: The protocol descriptor to use + * @r_evt: The registered event descriptor to use + * + * Read an event payload from the protocol queue into the dedicated scratch + * buffer, fills a custom report and then look for matching event handlers and + * call them; skip any unknown event (as marked by scmi_process_event_header()) + * and in case an anomalously sized read is detected just flush the queue. + * + * Return: False when the queue is empty + */ +static inline bool +scmi_process_event_payload(struct events_queue *eq, + struct scmi_registered_events_desc *pd, + struct scmi_registered_event *r_evt) +{ + u32 src_id, key; + unsigned int outs; + void *report = NULL; + + outs = kfifo_out(&eq->kfifo, pd->eh->payld, pd->eh->payld_sz); + if (!outs) + return false; + + /* Any in-flight event has now been officially processed */ + pd->in_flight = NULL; + + if (outs != pd->eh->payld_sz) { + dev_err(pd->ni->handle->dev, "corrupted EVT Payload. Flush.\n"); + kfifo_reset_out(&eq->kfifo); + return false; + } + + if (IS_ERR(r_evt)) { + dev_warn(pd->ni->handle->dev, + "SKIP UNKNOWN EVT - proto:%X evt:%d\n", + pd->id, pd->eh->evt_id); + return true; + } + + report = REVT_FILL_REPORT(r_evt, pd->eh->evt_id, pd->eh->timestamp, + pd->eh->payld, pd->eh->payld_sz, + r_evt->report, &src_id); + if (!report) { + dev_err(pd->ni->handle->dev, + "report not available - proto:%X evt:%d\n", + pd->id, pd->eh->evt_id); + return true; + } + + /* At first search for a generic ALL src_ids handler... */ + key = MAKE_ALL_SRCS_KEY(pd->id, pd->eh->evt_id); + scmi_lookup_and_call_event_chain(pd->ni, key, report); + + /* ...then search for any specific src_id */ + key = MAKE_HASH_KEY(pd->id, pd->eh->evt_id, src_id); + scmi_lookup_and_call_event_chain(pd->ni, key, report); + + return true; +} + +/** + * scmi_events_dispatcher() - Common worker logic for all work items. + * @work: The work item to use, which is associated to a dedicated events_queue + * + * Logic: + * 1. dequeue one pending RX notification (queued in SCMI RX ISR context) + * 2. generate a custom event report from the received event message + * 3. lookup for any registered ALL_SRC_IDs handler: + * - > call the related notification chain passing in the report + * 4. lookup for any registered specific SRC_ID handler: + * - > call the related notification chain passing in the report + * + * Note that: + * * a dedicated per-protocol kfifo queue is used: in this way an anomalous + * flood of events cannot saturate other protocols' queues. + * * each per-protocol queue is associated to a distinct work_item, which + * means, in turn, that: + * + all protocols can process their dedicated queues concurrently + * (since notify_wq:max_active != 1) + * + anyway at most one worker instance is allowed to run on the same queue + * concurrently: this ensures that we can have only one concurrent + * reader/writer on the associated kfifo, so that we can use it lock-less + * + * Context: Process context. + */ +static void scmi_events_dispatcher(struct work_struct *work) +{ + struct events_queue *eq; + struct scmi_registered_events_desc *pd; + struct scmi_registered_event *r_evt; + + eq = container_of(work, struct events_queue, notify_work); + pd = container_of(eq, struct scmi_registered_events_desc, equeue); + /* + * In order to keep the queue lock-less and the number of memcopies + * to the bare minimum needed, the dispatcher accounts for the + * possibility of per-protocol in-flight events: i.e. an event whose + * reception could end up being split across two subsequent runs of this + * worker, first the header, then the payload. + */ + do { + if (!pd->in_flight) { + r_evt = scmi_process_event_header(eq, pd); + if (!r_evt) + break; + pd->in_flight = r_evt; + } else { + r_evt = pd->in_flight; + } + } while (scmi_process_event_payload(eq, pd, r_evt)); +} + +/** + * scmi_notify() - Queues a notification for further deferred processing + * @handle: The handle identifying the platform instance from which the + * dispatched event is generated + * @proto_id: Protocol ID + * @evt_id: Event ID (msgID) + * @buf: Event Message Payload (without the header) + * @len: Event Message Payload size + * @ts: RX Timestamp in nanoseconds (boottime) + * + * Context: Called in interrupt context to queue a received event for + * deferred processing. + * + * Return: 0 on Success + */ +int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, + const void *buf, size_t len, ktime_t ts) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_header eh; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return 0; + ni = handle->notify_priv; + + r_evt = SCMI_GET_REVT(ni, proto_id, evt_id); + if (!r_evt) + return -EINVAL; + + if (len > r_evt->evt->max_payld_sz) { + dev_err(handle->dev, "discard badly sized message\n"); + return -EINVAL; + } + if (kfifo_avail(&r_evt->proto->equeue.kfifo) < sizeof(eh) + len) { + dev_warn(handle->dev, + "queue full, dropping proto_id:%d evt_id:%d ts:%lld\n", + proto_id, evt_id, ktime_to_ns(ts)); + return -ENOMEM; + } + + eh.timestamp = ts; + eh.evt_id = evt_id; + eh.payld_sz = len; + /* + * Header and payload are enqueued with two distinct kfifo_in() (so non + * atomic), but this situation is handled properly on the consumer side + * with in-flight events tracking. + */ + kfifo_in(&r_evt->proto->equeue.kfifo, &eh, sizeof(eh)); + kfifo_in(&r_evt->proto->equeue.kfifo, buf, len); + /* + * Don't care about return value here since we just want to ensure that + * a work is queued all the times whenever some items have been pushed + * on the kfifo: + * - if work was already queued it will simply fail to queue a new one + * since it is not needed + * - if work was not queued already it will be now, even in case work + * was in fact already running: this behavior avoids any possible race + * when this function pushes new items onto the kfifos after the + * related executing worker had already determined the kfifo to be + * empty and it was terminating. + */ + queue_work(r_evt->proto->equeue.wq, + &r_evt->proto->equeue.notify_work); + + return 0; +} + +/** + * scmi_kfifo_free() - Devres action helper to free the kfifo + * @kfifo: The kfifo to free + */ +static void scmi_kfifo_free(void *kfifo) +{ + kfifo_free((struct kfifo *)kfifo); +} + +/** + * scmi_initialize_events_queue() - Allocate/Initialize a kfifo buffer + * @ni: A reference to the notification instance to use + * @equeue: The events_queue to initialize + * @sz: Size of the kfifo buffer to allocate + * + * Allocate a buffer for the kfifo and initialize it. + * + * Return: 0 on Success + */ +static int scmi_initialize_events_queue(struct scmi_notify_instance *ni, + struct events_queue *equeue, size_t sz) +{ + int ret; + + if (kfifo_alloc(&equeue->kfifo, sz, GFP_KERNEL)) + return -ENOMEM; + /* Size could have been roundup to power-of-two */ + equeue->sz = kfifo_size(&equeue->kfifo); + + ret = devm_add_action_or_reset(ni->handle->dev, scmi_kfifo_free, + &equeue->kfifo); + if (ret) + return ret; + + INIT_WORK(&equeue->notify_work, scmi_events_dispatcher); + equeue->wq = ni->notify_wq; + + return ret; +} + +/** + * scmi_allocate_registered_events_desc() - Allocate a registered events' + * descriptor + * @ni: A reference to the &struct scmi_notify_instance notification instance + * to use + * @proto_id: Protocol ID + * @queue_sz: Size of the associated queue to allocate + * @eh_sz: Size of the event header scratch area to pre-allocate + * @num_events: Number of events to support (size of @registered_events) + * @ops: Pointer to a struct holding references to protocol specific helpers + * needed during events handling + * + * It is supposed to be called only once for each protocol at protocol + * initialization time, so it warns if the requested protocol is found already + * registered. + * + * Return: The allocated and registered descriptor on Success + */ +static struct scmi_registered_events_desc * +scmi_allocate_registered_events_desc(struct scmi_notify_instance *ni, + u8 proto_id, size_t queue_sz, size_t eh_sz, + int num_events, + const struct scmi_event_ops *ops) +{ + int ret; + struct scmi_registered_events_desc *pd; + + /* Ensure protocols are up to date */ + smp_rmb(); + if (WARN_ON(ni->registered_protocols[proto_id])) + return ERR_PTR(-EINVAL); + + pd = devm_kzalloc(ni->handle->dev, sizeof(*pd), GFP_KERNEL); + if (!pd) + return ERR_PTR(-ENOMEM); + pd->id = proto_id; + pd->ops = ops; + pd->ni = ni; + + ret = scmi_initialize_events_queue(ni, &pd->equeue, queue_sz); + if (ret) + return ERR_PTR(ret); + + pd->eh = devm_kzalloc(ni->handle->dev, eh_sz, GFP_KERNEL); + if (!pd->eh) + return ERR_PTR(-ENOMEM); + pd->eh_sz = eh_sz; + + pd->registered_events = devm_kcalloc(ni->handle->dev, num_events, + sizeof(char *), GFP_KERNEL); + if (!pd->registered_events) + return ERR_PTR(-ENOMEM); + pd->num_events = num_events; + + /* Initialize per protocol handlers table */ + mutex_init(&pd->registered_mtx); + hash_init(pd->registered_events_handlers); + + return pd; +} + +/** + * scmi_register_protocol_events() - Register Protocol Events with the core + * @handle: The handle identifying the platform instance against which the + * the protocol's events are registered + * @proto_id: Protocol ID + * @queue_sz: Size in bytes of the associated queue to be allocated + * @ops: Protocol specific event-related operations + * @evt: Event descriptor array + * @num_events: Number of events in @evt array + * @num_sources: Number of possible sources for this protocol on this + * platform. + * + * Used by SCMI Protocols initialization code to register with the notification + * core the list of supported events and their descriptors: takes care to + * pre-allocate and store all needed descriptors, scratch buffers and event + * queues. + * + * Return: 0 on Success + */ +int scmi_register_protocol_events(const struct scmi_handle *handle, + u8 proto_id, size_t queue_sz, + const struct scmi_event_ops *ops, + const struct scmi_event *evt, int num_events, + int num_sources) +{ + int i; + size_t payld_sz = 0; + struct scmi_registered_events_desc *pd; + struct scmi_notify_instance *ni; + + if (!ops || !evt) + return -EINVAL; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENOMEM; + ni = handle->notify_priv; + + /* Attach to the notification main devres group */ + if (!devres_open_group(ni->handle->dev, ni->gid, GFP_KERNEL)) + return -ENOMEM; + + for (i = 0; i < num_events; i++) + payld_sz = max_t(size_t, payld_sz, evt[i].max_payld_sz); + payld_sz += sizeof(struct scmi_event_header); + + pd = scmi_allocate_registered_events_desc(ni, proto_id, queue_sz, + payld_sz, num_events, ops); + if (IS_ERR(pd)) + goto err; + + for (i = 0; i < num_events; i++, evt++) { + struct scmi_registered_event *r_evt; + + r_evt = devm_kzalloc(ni->handle->dev, sizeof(*r_evt), + GFP_KERNEL); + if (!r_evt) + goto err; + r_evt->proto = pd; + r_evt->evt = evt; + + r_evt->sources = devm_kcalloc(ni->handle->dev, num_sources, + sizeof(refcount_t), GFP_KERNEL); + if (!r_evt->sources) + goto err; + r_evt->num_sources = num_sources; + mutex_init(&r_evt->sources_mtx); + + r_evt->report = devm_kzalloc(ni->handle->dev, + evt->max_report_sz, GFP_KERNEL); + if (!r_evt->report) + goto err; + + pd->registered_events[i] = r_evt; + /* Ensure events are updated */ + smp_wmb(); + dev_dbg(handle->dev, "registered event - %lX\n", + MAKE_ALL_SRCS_KEY(r_evt->proto->id, r_evt->evt->id)); + } + + /* Register protocol and events...it will never be removed */ + ni->registered_protocols[proto_id] = pd; + /* Ensure protocols are updated */ + smp_wmb(); + + devres_close_group(ni->handle->dev, ni->gid); + + /* + * Finalize any pending events' handler which could have been waiting + * for this protocol's events registration. + */ + schedule_work(&ni->init_work); + + return 0; + +err: + dev_warn(handle->dev, "Proto:%X - Registration Failed !\n", proto_id); + /* A failing protocol registration does not trigger full failure */ + devres_close_group(ni->handle->dev, ni->gid); + + return -ENOMEM; +} + +/** + * scmi_allocate_event_handler() - Allocate Event handler + * @ni: A reference to the notification instance to use + * @evt_key: 32bit key uniquely bind to the event identified by the tuple + * (proto_id, evt_id, src_id) + * + * Allocate an event handler and related notification chain associated with + * the provided event handler key. + * Note that, at this point, a related registered_event is still to be + * associated to this handler descriptor (hndl->r_evt == NULL), so the handler + * is initialized as pending. + * + * Context: Assumes to be called with @pending_mtx already acquired. + * Return: the freshly allocated structure on Success + */ +static struct scmi_event_handler * +scmi_allocate_event_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + struct scmi_event_handler *hndl; + + hndl = kzalloc(sizeof(*hndl), GFP_KERNEL); + if (!hndl) + return NULL; + hndl->key = evt_key; + BLOCKING_INIT_NOTIFIER_HEAD(&hndl->chain); + refcount_set(&hndl->users, 1); + /* New handlers are created pending */ + hash_add(ni->pending_events_handlers, &hndl->hash, hndl->key); + + return hndl; +} + +/** + * scmi_free_event_handler() - Free the provided Event handler + * @hndl: The event handler structure to free + * + * Context: Assumes to be called with proper locking acquired depending + * on the situation. + */ +static void scmi_free_event_handler(struct scmi_event_handler *hndl) +{ + hash_del(&hndl->hash); + kfree(hndl); +} + +/** + * scmi_bind_event_handler() - Helper to attempt binding an handler to an event + * @ni: A reference to the notification instance to use + * @hndl: The event handler to bind + * + * If an associated registered event is found, move the handler from the pending + * into the registered table. + * + * Context: Assumes to be called with @pending_mtx already acquired. + * + * Return: 0 on Success + */ +static inline int scmi_bind_event_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(hndl->key), + KEY_XTRACT_EVT_ID(hndl->key)); + if (!r_evt) + return -EINVAL; + + /* Remove from pending and insert into registered */ + hash_del(&hndl->hash); + hndl->r_evt = r_evt; + mutex_lock(&r_evt->proto->registered_mtx); + hash_add(r_evt->proto->registered_events_handlers, + &hndl->hash, hndl->key); + mutex_unlock(&r_evt->proto->registered_mtx); + + return 0; +} + +/** + * scmi_valid_pending_handler() - Helper to check pending status of handlers + * @ni: A reference to the notification instance to use + * @hndl: The event handler to check + * + * An handler is considered pending when its r_evt == NULL, because the related + * event was still unknown at handler's registration time; anyway, since all + * protocols register their supported events once for all at protocols' + * initialization time, a pending handler cannot be considered valid anymore if + * the underlying event (which it is waiting for), belongs to an already + * initialized and registered protocol. + * + * Return: 0 on Success + */ +static inline int scmi_valid_pending_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_events_desc *pd; + + if (!IS_HNDL_PENDING(hndl)) + return -EINVAL; + + pd = SCMI_GET_PROTO(ni, KEY_XTRACT_PROTO_ID(hndl->key)); + if (pd) + return -EINVAL; + + return 0; +} + +/** + * scmi_register_event_handler() - Register whenever possible an Event handler + * @ni: A reference to the notification instance to use + * @hndl: The event handler to register + * + * At first try to bind an event handler to its associated event, then check if + * it was at least a valid pending handler: if it was not bound nor valid return + * false. + * + * Valid pending incomplete bindings will be periodically retried by a dedicated + * worker which is kicked each time a new protocol completes its own + * registration phase. + * + * Context: Assumes to be called with @pending_mtx acquired. + * + * Return: 0 on Success + */ +static int scmi_register_event_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + int ret; + + ret = scmi_bind_event_handler(ni, hndl); + if (!ret) { + dev_dbg(ni->handle->dev, "registered NEW handler - key:%X\n", + hndl->key); + } else { + ret = scmi_valid_pending_handler(ni, hndl); + if (!ret) + dev_dbg(ni->handle->dev, + "registered PENDING handler - key:%X\n", + hndl->key); + } + + return ret; +} + +/** + * __scmi_event_handler_get_ops() - Utility to get or create an event handler + * @ni: A reference to the notification instance to use + * @evt_key: The event key to use + * @create: A boolean flag to specify if a handler must be created when + * not already existent + * + * Search for the desired handler matching the key in both the per-protocol + * registered table and the common pending table: + * * if found adjust users refcount + * * if not found and @create is true, create and register the new handler: + * handler could end up being registered as pending if no matching event + * could be found. + * + * An handler is guaranteed to reside in one and only one of the tables at + * any one time; to ensure this the whole search and create is performed + * holding the @pending_mtx lock, with @registered_mtx additionally acquired + * if needed. + * + * Note that when a nested acquisition of these mutexes is needed the locking + * order is always (same as in @init_work): + * 1. pending_mtx + * 2. registered_mtx + * + * Events generation is NOT enabled right after creation within this routine + * since at creation time we usually want to have all setup and ready before + * events really start flowing. + * + * Return: A properly refcounted handler on Success, NULL on Failure + */ +static inline struct scmi_event_handler * +__scmi_event_handler_get_ops(struct scmi_notify_instance *ni, + u32 evt_key, bool create) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_handler *hndl = NULL; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(evt_key), + KEY_XTRACT_EVT_ID(evt_key)); + + mutex_lock(&ni->pending_mtx); + /* Search registered events at first ... if possible at all */ + if (r_evt) { + mutex_lock(&r_evt->proto->registered_mtx); + hndl = KEY_FIND(r_evt->proto->registered_events_handlers, + hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + mutex_unlock(&r_evt->proto->registered_mtx); + } + + /* ...then amongst pending. */ + if (!hndl) { + hndl = KEY_FIND(ni->pending_events_handlers, hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + } + + /* Create if still not found and required */ + if (!hndl && create) { + hndl = scmi_allocate_event_handler(ni, evt_key); + if (hndl && scmi_register_event_handler(ni, hndl)) { + dev_dbg(ni->handle->dev, + "purging UNKNOWN handler - key:%X\n", + hndl->key); + /* this hndl can be only a pending one */ + scmi_put_handler_unlocked(ni, hndl); + hndl = NULL; + } + } + mutex_unlock(&ni->pending_mtx); + + return hndl; +} + +static struct scmi_event_handler * +scmi_get_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + return __scmi_event_handler_get_ops(ni, evt_key, false); +} + +static struct scmi_event_handler * +scmi_get_or_create_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + return __scmi_event_handler_get_ops(ni, evt_key, true); +} + +/** + * scmi_get_active_handler() - Helper to get active handlers only + * @ni: A reference to the notification instance to use + * @evt_key: The event key to use + * + * Search for the desired handler matching the key only in the per-protocol + * table of registered handlers: this is called only from the dispatching path + * so want to be as quick as possible and do not care about pending. + * + * Return: A properly refcounted active handler + */ +static struct scmi_event_handler * +scmi_get_active_handler(struct scmi_notify_instance *ni, u32 evt_key) +{ + struct scmi_registered_event *r_evt; + struct scmi_event_handler *hndl = NULL; + + r_evt = SCMI_GET_REVT(ni, KEY_XTRACT_PROTO_ID(evt_key), + KEY_XTRACT_EVT_ID(evt_key)); + if (r_evt) { + mutex_lock(&r_evt->proto->registered_mtx); + hndl = KEY_FIND(r_evt->proto->registered_events_handlers, + hndl, evt_key); + if (hndl) + refcount_inc(&hndl->users); + mutex_unlock(&r_evt->proto->registered_mtx); + } + + return hndl; +} + +/** + * __scmi_enable_evt() - Enable/disable events generation + * @r_evt: The registered event to act upon + * @src_id: The src_id to act upon + * @enable: The action to perform: true->Enable, false->Disable + * + * Takes care of proper refcounting while performing enable/disable: handles + * the special case of ALL sources requests by itself. + * Returns successfully if at least one of the required src_id has been + * successfully enabled/disabled. + * + * Return: 0 on Success + */ +static inline int __scmi_enable_evt(struct scmi_registered_event *r_evt, + u32 src_id, bool enable) +{ + int retvals = 0; + u32 num_sources; + refcount_t *sid; + + if (src_id == SRC_ID_MASK) { + src_id = 0; + num_sources = r_evt->num_sources; + } else if (src_id < r_evt->num_sources) { + num_sources = 1; + } else { + return -EINVAL; + } + + mutex_lock(&r_evt->sources_mtx); + if (enable) { + for (; num_sources; src_id++, num_sources--) { + int ret = 0; + + sid = &r_evt->sources[src_id]; + if (refcount_read(sid) == 0) { + ret = REVT_NOTIFY_ENABLE(r_evt, r_evt->evt->id, + src_id); + if (!ret) + refcount_set(sid, 1); + } else { + refcount_inc(sid); + } + retvals += !ret; + } + } else { + for (; num_sources; src_id++, num_sources--) { + sid = &r_evt->sources[src_id]; + if (refcount_dec_and_test(sid)) + REVT_NOTIFY_DISABLE(r_evt, + r_evt->evt->id, src_id); + } + retvals = 1; + } + mutex_unlock(&r_evt->sources_mtx); + + return retvals ? 0 : -EINVAL; +} + +static int scmi_enable_events(struct scmi_event_handler *hndl) +{ + int ret = 0; + + if (!hndl->enabled) { + ret = __scmi_enable_evt(hndl->r_evt, + KEY_XTRACT_SRC_ID(hndl->key), true); + if (!ret) + hndl->enabled = true; + } + + return ret; +} + +static int scmi_disable_events(struct scmi_event_handler *hndl) +{ + int ret = 0; + + if (hndl->enabled) { + ret = __scmi_enable_evt(hndl->r_evt, + KEY_XTRACT_SRC_ID(hndl->key), false); + if (!ret) + hndl->enabled = false; + } + + return ret; +} + +/** + * scmi_put_handler_unlocked() - Put an event handler + * @ni: A reference to the notification instance to use + * @hndl: The event handler to act upon + * + * After having got exclusive access to the registered handlers hashtable, + * update the refcount and if @hndl is no more in use by anyone: + * * ask for events' generation disabling + * * unregister and free the handler itself + * + * Context: Assumes all the proper locking has been managed by the caller. + */ +static void scmi_put_handler_unlocked(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + if (refcount_dec_and_test(&hndl->users)) { + if (!IS_HNDL_PENDING(hndl)) + scmi_disable_events(hndl); + scmi_free_event_handler(hndl); + } +} + +static void scmi_put_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt = hndl->r_evt; + + mutex_lock(&ni->pending_mtx); + if (r_evt) + mutex_lock(&r_evt->proto->registered_mtx); + + scmi_put_handler_unlocked(ni, hndl); + + if (r_evt) + mutex_unlock(&r_evt->proto->registered_mtx); + mutex_unlock(&ni->pending_mtx); +} + +static void scmi_put_active_handler(struct scmi_notify_instance *ni, + struct scmi_event_handler *hndl) +{ + struct scmi_registered_event *r_evt = hndl->r_evt; + + mutex_lock(&r_evt->proto->registered_mtx); + scmi_put_handler_unlocked(ni, hndl); + mutex_unlock(&r_evt->proto->registered_mtx); +} + +/** + * scmi_event_handler_enable_events() - Enable events associated to an handler + * @hndl: The Event handler to act upon + * + * Return: 0 on Success + */ +static int scmi_event_handler_enable_events(struct scmi_event_handler *hndl) +{ + if (scmi_enable_events(hndl)) { + pr_err("Failed to ENABLE events for key:%X !\n", hndl->key); + return -EINVAL; + } + + return 0; +} + +/** + * scmi_register_notifier() - Register a notifier_block for an event + * @handle: The handle identifying the platform instance against which the + * callback is registered + * @proto_id: Protocol ID + * @evt_id: Event ID + * @src_id: Source ID, when NULL register for events coming form ALL possible + * sources + * @nb: A standard notifier block to register for the specified event + * + * Generic helper to register a notifier_block against a protocol event. + * + * A notifier_block @nb will be registered for each distinct event identified + * by the tuple (proto_id, evt_id, src_id) on a dedicated notification chain + * so that: + * + * (proto_X, evt_Y, src_Z) --> chain_X_Y_Z + * + * @src_id meaning is protocol specific and identifies the origin of the event + * (like domain_id, sensor_id and so forth). + * + * @src_id can be NULL to signify that the caller is interested in receiving + * notifications from ALL the available sources for that protocol OR simply that + * the protocol does not support distinct sources. + * + * As soon as one user for the specified tuple appears, an handler is created, + * and that specific event's generation is enabled at the platform level, unless + * an associated registered event is found missing, meaning that the needed + * protocol is still to be initialized and the handler has just been registered + * as still pending. + * + * Return: 0 on Success + */ +static int scmi_register_notifier(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb) +{ + int ret = 0; + u32 evt_key; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENODEV; + ni = handle->notify_priv; + + evt_key = MAKE_HASH_KEY(proto_id, evt_id, + src_id ? *src_id : SRC_ID_MASK); + hndl = scmi_get_or_create_handler(ni, evt_key); + if (!hndl) + return -EINVAL; + + blocking_notifier_chain_register(&hndl->chain, nb); + + /* Enable events for not pending handlers */ + if (!IS_HNDL_PENDING(hndl)) { + ret = scmi_event_handler_enable_events(hndl); + if (ret) + scmi_put_handler(ni, hndl); + } + + return ret; +} + +/** + * scmi_unregister_notifier() - Unregister a notifier_block for an event + * @handle: The handle identifying the platform instance against which the + * callback is unregistered + * @proto_id: Protocol ID + * @evt_id: Event ID + * @src_id: Source ID + * @nb: The notifier_block to unregister + * + * Takes care to unregister the provided @nb from the notification chain + * associated to the specified event and, if there are no more users for the + * event handler, frees also the associated event handler structures. + * (this could possibly cause disabling of event's generation at platform level) + * + * Return: 0 on Success + */ +static int scmi_unregister_notifier(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb) +{ + u32 evt_key; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return -ENODEV; + ni = handle->notify_priv; + + evt_key = MAKE_HASH_KEY(proto_id, evt_id, + src_id ? *src_id : SRC_ID_MASK); + hndl = scmi_get_handler(ni, evt_key); + if (!hndl) + return -EINVAL; + + /* + * Note that this chain unregistration call is safe on its own + * being internally protected by an rwsem. + */ + blocking_notifier_chain_unregister(&hndl->chain, nb); + scmi_put_handler(ni, hndl); + + /* + * This balances the initial get issued in @scmi_register_notifier. + * If this notifier_block happened to be the last known user callback + * for this event, the handler is here freed and the event's generation + * stopped. + * + * Note that, an ongoing concurrent lookup on the delivery workqueue + * path could still hold the refcount to 1 even after this routine + * completes: in such a case it will be the final put on the delivery + * path which will finally free this unused handler. + */ + scmi_put_handler(ni, hndl); + + return 0; +} + +/** + * scmi_protocols_late_init() - Worker for late initialization + * @work: The work item to use associated to the proper SCMI instance + * + * This kicks in whenever a new protocol has completed its own registration via + * scmi_register_protocol_events(): it is in charge of scanning the table of + * pending handlers (registered by users while the related protocol was still + * not initialized) and finalizing their initialization whenever possible; + * invalid pending handlers are purged at this point in time. + */ +static void scmi_protocols_late_init(struct work_struct *work) +{ + int bkt; + struct scmi_event_handler *hndl; + struct scmi_notify_instance *ni; + struct hlist_node *tmp; + + ni = container_of(work, struct scmi_notify_instance, init_work); + + /* Ensure protocols and events are up to date */ + smp_rmb(); + + mutex_lock(&ni->pending_mtx); + hash_for_each_safe(ni->pending_events_handlers, bkt, tmp, hndl, hash) { + int ret; + + ret = scmi_bind_event_handler(ni, hndl); + if (!ret) { + dev_dbg(ni->handle->dev, + "finalized PENDING handler - key:%X\n", + hndl->key); + ret = scmi_event_handler_enable_events(hndl); + } else { + ret = scmi_valid_pending_handler(ni, hndl); + } + if (ret) { + dev_dbg(ni->handle->dev, + "purging PENDING handler - key:%X\n", + hndl->key); + /* this hndl can be only a pending one */ + scmi_put_handler_unlocked(ni, hndl); + } + } + mutex_unlock(&ni->pending_mtx); +} + +/* + * notify_ops are attached to the handle so that can be accessed + * directly from an scmi_driver to register its own notifiers. + */ +static struct scmi_notify_ops notify_ops = { + .register_event_notifier = scmi_register_notifier, + .unregister_event_notifier = scmi_unregister_notifier, +}; + +/** + * scmi_notification_init() - Initializes Notification Core Support + * @handle: The handle identifying the platform instance to initialize + * + * This function lays out all the basic resources needed by the notification + * core instance identified by the provided handle: once done, all of the + * SCMI Protocols can register their events with the core during their own + * initializations. + * + * Note that failing to initialize the core notifications support does not + * cause the whole SCMI Protocols stack to fail its initialization. + * + * SCMI Notification Initialization happens in 2 steps: + * * initialization: basic common allocations (this function) + * * registration: protocols asynchronously come into life and registers their + * own supported list of events with the core; this causes + * further per-protocol allocations + * + * Any user's callback registration attempt, referring a still not registered + * event, will be registered as pending and finalized later (if possible) + * by scmi_protocols_late_init() work. + * This allows for lazy initialization of SCMI Protocols due to late (or + * missing) SCMI drivers' modules loading. + * + * Return: 0 on Success + */ +int scmi_notification_init(struct scmi_handle *handle) +{ + void *gid; + struct scmi_notify_instance *ni; + + gid = devres_open_group(handle->dev, NULL, GFP_KERNEL); + if (!gid) + return -ENOMEM; + + ni = devm_kzalloc(handle->dev, sizeof(*ni), GFP_KERNEL); + if (!ni) + goto err; + + ni->gid = gid; + ni->handle = handle; + + ni->notify_wq = alloc_workqueue("scmi_notify", + WQ_UNBOUND | WQ_FREEZABLE | WQ_SYSFS, + 0); + if (!ni->notify_wq) + goto err; + + ni->registered_protocols = devm_kcalloc(handle->dev, SCMI_MAX_PROTO, + sizeof(char *), GFP_KERNEL); + if (!ni->registered_protocols) + goto err; + + mutex_init(&ni->pending_mtx); + hash_init(ni->pending_events_handlers); + + INIT_WORK(&ni->init_work, scmi_protocols_late_init); + + handle->notify_ops = ¬ify_ops; + handle->notify_priv = ni; + /* Ensure handle is up to date */ + smp_wmb(); + + dev_info(handle->dev, "Core Enabled.\n"); + + devres_close_group(handle->dev, ni->gid); + + return 0; + +err: + dev_warn(handle->dev, "Initialization Failed.\n"); + devres_release_group(handle->dev, NULL); + return -ENOMEM; +} + +/** + * scmi_notification_exit() - Shutdown and clean Notification core + * @handle: The handle identifying the platform instance to shutdown + */ +void scmi_notification_exit(struct scmi_handle *handle) +{ + struct scmi_notify_instance *ni; + + /* Ensure notify_priv is updated */ + smp_rmb(); + if (!handle->notify_priv) + return; + ni = handle->notify_priv; + + handle->notify_priv = NULL; + /* Ensure handle is up to date */ + smp_wmb(); + + /* Destroy while letting pending work complete */ + destroy_workqueue(ni->notify_wq); + + devres_release_group(ni->handle->dev, ni->gid); +} diff --git a/drivers/firmware/arm_scmi/notify.h b/drivers/firmware/arm_scmi/notify.h new file mode 100644 index 000000000000..3485f20fa70e --- /dev/null +++ b/drivers/firmware/arm_scmi/notify.h @@ -0,0 +1,68 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * System Control and Management Interface (SCMI) Message Protocol + * notification header file containing some definitions, structures + * and function prototypes related to SCMI Notification handling. + * + * Copyright (C) 2020 ARM Ltd. + */ +#ifndef _SCMI_NOTIFY_H +#define _SCMI_NOTIFY_H + +#include <linux/device.h> +#include <linux/ktime.h> +#include <linux/types.h> + +#define SCMI_PROTO_QUEUE_SZ 4096 + +/** + * struct scmi_event - Describes an event to be supported + * @id: Event ID + * @max_payld_sz: Max possible size for the payload of a notification message + * @max_report_sz: Max possible size for the report of a notification message + * + * Each SCMI protocol, during its initialization phase, can describe the events + * it wishes to support in a few struct scmi_event and pass them to the core + * using scmi_register_protocol_events(). + */ +struct scmi_event { + u8 id; + size_t max_payld_sz; + size_t max_report_sz; +}; + +/** + * struct scmi_event_ops - Protocol helpers called by the notification core. + * @set_notify_enabled: Enable/disable the required evt_id/src_id notifications + * using the proper custom protocol commands. + * Return 0 on Success + * @fill_custom_report: fills a custom event report from the provided + * event message payld identifying the event + * specific src_id. + * Return NULL on failure otherwise @report now fully + * populated + * + * Context: Helpers described in &struct scmi_event_ops are called only in + * process context. + */ +struct scmi_event_ops { + int (*set_notify_enabled)(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enabled); + void *(*fill_custom_report)(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id); +}; + +int scmi_notification_init(struct scmi_handle *handle); +void scmi_notification_exit(struct scmi_handle *handle); + +int scmi_register_protocol_events(const struct scmi_handle *handle, + u8 proto_id, size_t queue_sz, + const struct scmi_event_ops *ops, + const struct scmi_event *evt, int num_events, + int num_sources); +int scmi_notify(const struct scmi_handle *handle, u8 proto_id, u8 evt_id, + const void *buf, size_t len, ktime_t ts); + +#endif /* _SCMI_NOTIFY_H */ diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c index eadc171e254b..3e1e87012c95 100644 --- a/drivers/firmware/arm_scmi/perf.c +++ b/drivers/firmware/arm_scmi/perf.c @@ -5,15 +5,19 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications PERF - " fmt + #include <linux/bits.h> #include <linux/of.h> #include <linux/io.h> #include <linux/io-64-nonatomic-hi-lo.h> #include <linux/platform_device.h> #include <linux/pm_opp.h> +#include <linux/scmi_protocol.h> #include <linux/sort.h> #include "common.h" +#include "notify.h" enum scmi_performance_protocol_cmd { PERF_DOMAIN_ATTRIBUTES = 0x3, @@ -27,11 +31,6 @@ enum scmi_performance_protocol_cmd { PERF_DESCRIBE_FASTCHANNEL = 0xb, }; -enum scmi_performance_protocol_notify { - PERFORMANCE_LIMITS_CHANGED = 0x0, - PERFORMANCE_LEVEL_CHANGED = 0x1, -}; - struct scmi_opp { u32 perf; u32 power; @@ -86,6 +85,19 @@ struct scmi_perf_notify_level_or_limits { __le32 notify_enable; }; +struct scmi_perf_limits_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 range_max; + __le32 range_min; +}; + +struct scmi_perf_level_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 performance_level; +}; + struct scmi_msg_resp_perf_describe_levels { __le16 num_returned; __le16 num_remaining; @@ -158,6 +170,11 @@ struct scmi_perf_info { struct perf_dom_info *dom_info; }; +static enum scmi_performance_protocol_cmd evt_2_cmd[] = { + PERF_NOTIFY_LIMITS, + PERF_NOTIFY_LEVEL, +}; + static int scmi_perf_attributes_get(const struct scmi_handle *handle, struct scmi_perf_info *pi) { @@ -488,6 +505,29 @@ static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain, return scmi_perf_mb_level_get(handle, domain, level, poll); } +static int scmi_perf_level_limits_notify(const struct scmi_handle *handle, + u32 domain, int message_id, + bool enable) +{ + int ret; + struct scmi_xfer *t; + struct scmi_perf_notify_level_or_limits *notify; + + ret = scmi_xfer_get_init(handle, message_id, SCMI_PROTOCOL_PERF, + sizeof(*notify), 0, &t); + if (ret) + return ret; + + notify = t->tx.buf; + notify->domain = cpu_to_le32(domain); + notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0; + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size) { if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4) @@ -697,6 +737,17 @@ static int scmi_dvfs_est_power_get(const struct scmi_handle *handle, u32 domain, return ret; } +static bool scmi_fast_switch_possible(const struct scmi_handle *handle, + struct device *dev) +{ + struct perf_dom_info *dom; + struct scmi_perf_info *pi = handle->perf_priv; + + dom = pi->dom_info + scmi_dev_domain_id(dev); + + return dom->fc_info && dom->fc_info->level_set_addr; +} + static struct scmi_perf_ops perf_ops = { .limits_set = scmi_perf_limits_set, .limits_get = scmi_perf_limits_get, @@ -708,6 +759,90 @@ static struct scmi_perf_ops perf_ops = { .freq_set = scmi_dvfs_freq_set, .freq_get = scmi_dvfs_freq_get, .est_power_get = scmi_dvfs_est_power_get, + .fast_switch_possible = scmi_fast_switch_possible, +}; + +static int scmi_perf_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret, cmd_id; + + if (evt_id >= ARRAY_SIZE(evt_2_cmd)) + return -EINVAL; + + cmd_id = evt_2_cmd[evt_id]; + ret = scmi_perf_level_limits_notify(handle, src_id, cmd_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_perf_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + void *rep = NULL; + + switch (evt_id) { + case SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED: + { + const struct scmi_perf_limits_notify_payld *p = payld; + struct scmi_perf_limits_report *r = report; + + if (sizeof(*p) != payld_sz) + break; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->range_max = le32_to_cpu(p->range_max); + r->range_min = le32_to_cpu(p->range_min); + *src_id = r->domain_id; + rep = r; + break; + } + case SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED: + { + const struct scmi_perf_level_notify_payld *p = payld; + struct scmi_perf_level_report *r = report; + + if (sizeof(*p) != payld_sz) + break; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->performance_level = le32_to_cpu(p->performance_level); + *src_id = r->domain_id; + rep = r; + break; + } + default: + break; + } + + return rep; +} + +static const struct scmi_event perf_events[] = { + { + .id = SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED, + .max_payld_sz = sizeof(struct scmi_perf_limits_notify_payld), + .max_report_sz = sizeof(struct scmi_perf_limits_report), + }, + { + .id = SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED, + .max_payld_sz = sizeof(struct scmi_perf_level_notify_payld), + .max_report_sz = sizeof(struct scmi_perf_level_report), + }, +}; + +static const struct scmi_event_ops perf_event_ops = { + .set_notify_enabled = scmi_perf_set_notify_enabled, + .fill_custom_report = scmi_perf_fill_custom_report, }; static int scmi_perf_protocol_init(struct scmi_handle *handle) @@ -742,6 +877,12 @@ static int scmi_perf_protocol_init(struct scmi_handle *handle) scmi_perf_domain_init_fc(handle, domain, &dom->fc_info); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_PERF, SCMI_PROTO_QUEUE_SZ, + &perf_event_ops, perf_events, + ARRAY_SIZE(perf_events), + pinfo->num_domains); + pinfo->version = version; handle->perf_ops = &perf_ops; handle->perf_priv = pinfo; diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c index cf7f0312381b..46f213644c49 100644 --- a/drivers/firmware/arm_scmi/power.c +++ b/drivers/firmware/arm_scmi/power.c @@ -5,19 +5,18 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications POWER - " fmt + +#include <linux/scmi_protocol.h> + #include "common.h" +#include "notify.h" enum scmi_power_protocol_cmd { POWER_DOMAIN_ATTRIBUTES = 0x3, POWER_STATE_SET = 0x4, POWER_STATE_GET = 0x5, POWER_STATE_NOTIFY = 0x6, - POWER_STATE_CHANGE_REQUESTED_NOTIFY = 0x7, -}; - -enum scmi_power_protocol_notify { - POWER_STATE_CHANGED = 0x0, - POWER_STATE_CHANGE_REQUESTED = 0x1, }; struct scmi_msg_resp_power_attributes { @@ -48,6 +47,12 @@ struct scmi_power_state_notify { __le32 notify_enable; }; +struct scmi_power_state_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 power_state; +}; + struct power_dom_info { bool state_set_sync; bool state_set_async; @@ -186,6 +191,75 @@ static struct scmi_power_ops power_ops = { .state_get = scmi_power_state_get, }; +static int scmi_power_request_notify(const struct scmi_handle *handle, + u32 domain, bool enable) +{ + int ret; + struct scmi_xfer *t; + struct scmi_power_state_notify *notify; + + ret = scmi_xfer_get_init(handle, POWER_STATE_NOTIFY, + SCMI_PROTOCOL_POWER, sizeof(*notify), 0, &t); + if (ret) + return ret; + + notify = t->tx.buf; + notify->domain = cpu_to_le32(domain); + notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0; + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_power_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_power_request_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_power_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_power_state_notify_payld *p = payld; + struct scmi_power_state_changed_report *r = report; + + if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->power_state = le32_to_cpu(p->power_state); + *src_id = r->domain_id; + + return r; +} + +static const struct scmi_event power_events[] = { + { + .id = SCMI_EVENT_POWER_STATE_CHANGED, + .max_payld_sz = sizeof(struct scmi_power_state_notify_payld), + .max_report_sz = + sizeof(struct scmi_power_state_changed_report), + }, +}; + +static const struct scmi_event_ops power_event_ops = { + .set_notify_enabled = scmi_power_set_notify_enabled, + .fill_custom_report = scmi_power_fill_custom_report, +}; + static int scmi_power_protocol_init(struct scmi_handle *handle) { int domain; @@ -214,6 +288,12 @@ static int scmi_power_protocol_init(struct scmi_handle *handle) scmi_power_domain_attributes_get(handle, domain, dom); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_POWER, SCMI_PROTO_QUEUE_SZ, + &power_event_ops, power_events, + ARRAY_SIZE(power_events), + pinfo->num_domains); + pinfo->version = version; handle->power_ops = &power_ops; handle->power_priv = pinfo; diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c index de73054554f3..3691bafca057 100644 --- a/drivers/firmware/arm_scmi/reset.c +++ b/drivers/firmware/arm_scmi/reset.c @@ -5,7 +5,12 @@ * Copyright (C) 2019 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications RESET - " fmt + +#include <linux/scmi_protocol.h> + #include "common.h" +#include "notify.h" enum scmi_reset_protocol_cmd { RESET_DOMAIN_ATTRIBUTES = 0x3, @@ -13,10 +18,6 @@ enum scmi_reset_protocol_cmd { RESET_NOTIFY = 0x5, }; -enum scmi_reset_protocol_notify { - RESET_ISSUED = 0x0, -}; - #define NUM_RESET_DOMAIN_MASK 0xffff #define RESET_NOTIFY_ENABLE BIT(0) @@ -40,6 +41,18 @@ struct scmi_msg_reset_domain_reset { #define ARCH_COLD_RESET (ARCH_RESET_TYPE | COLD_RESET_STATE) }; +struct scmi_msg_reset_notify { + __le32 id; + __le32 event_control; +#define RESET_TP_NOTIFY_ALL BIT(0) +}; + +struct scmi_reset_issued_notify_payld { + __le32 agent_id; + __le32 domain_id; + __le32 reset_state; +}; + struct reset_dom_info { bool async_reset; bool reset_notify; @@ -190,6 +203,75 @@ static struct scmi_reset_ops reset_ops = { .deassert = scmi_reset_domain_deassert, }; +static int scmi_reset_notify(const struct scmi_handle *handle, u32 domain_id, + bool enable) +{ + int ret; + u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0; + struct scmi_xfer *t; + struct scmi_msg_reset_notify *cfg; + + ret = scmi_xfer_get_init(handle, RESET_NOTIFY, + SCMI_PROTOCOL_RESET, sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->id = cpu_to_le32(domain_id); + cfg->event_control = cpu_to_le32(evt_cntl); + + ret = scmi_do_xfer(handle, t); + + scmi_xfer_put(handle, t); + return ret; +} + +static int scmi_reset_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_reset_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_reset_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_reset_issued_notify_payld *p = payld; + struct scmi_reset_issued_report *r = report; + + if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->domain_id = le32_to_cpu(p->domain_id); + r->reset_state = le32_to_cpu(p->reset_state); + *src_id = r->domain_id; + + return r; +} + +static const struct scmi_event reset_events[] = { + { + .id = SCMI_EVENT_RESET_ISSUED, + .max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld), + .max_report_sz = sizeof(struct scmi_reset_issued_report), + }, +}; + +static const struct scmi_event_ops reset_event_ops = { + .set_notify_enabled = scmi_reset_set_notify_enabled, + .fill_custom_report = scmi_reset_fill_custom_report, +}; + static int scmi_reset_protocol_init(struct scmi_handle *handle) { int domain; @@ -218,6 +300,12 @@ static int scmi_reset_protocol_init(struct scmi_handle *handle) scmi_reset_domain_attributes_get(handle, domain, dom); } + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_RESET, SCMI_PROTO_QUEUE_SZ, + &reset_event_ops, reset_events, + ARRAY_SIZE(reset_events), + pinfo->num_domains); + pinfo->version = version; handle->reset_ops = &reset_ops; handle->reset_priv = pinfo; diff --git a/drivers/firmware/arm_scmi/scmi_pm_domain.c b/drivers/firmware/arm_scmi/scmi_pm_domain.c index bafbfe358f97..9e44479f0284 100644 --- a/drivers/firmware/arm_scmi/scmi_pm_domain.c +++ b/drivers/firmware/arm_scmi/scmi_pm_domain.c @@ -85,7 +85,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) for (i = 0; i < num_domains; i++, scmi_pd++) { u32 state; - domains[i] = &scmi_pd->genpd; + if (handle->power_ops->state_get(handle, i, &state)) { + dev_warn(dev, "failed to get state for domain %d\n", i); + continue; + } scmi_pd->domain = i; scmi_pd->handle = handle; @@ -94,13 +97,10 @@ static int scmi_pm_domain_probe(struct scmi_device *sdev) scmi_pd->genpd.power_off = scmi_pd_power_off; scmi_pd->genpd.power_on = scmi_pd_power_on; - if (handle->power_ops->state_get(handle, i, &state)) { - dev_warn(dev, "failed to get state for domain %d\n", i); - continue; - } - pm_genpd_init(&scmi_pd->genpd, NULL, state == SCMI_POWER_STATE_GENERIC_OFF); + + domains[i] = &scmi_pd->genpd; } scmi_pd_data->domains = domains; diff --git a/drivers/firmware/arm_scmi/sensors.c b/drivers/firmware/arm_scmi/sensors.c index db1b1ab303da..1af0ad362e82 100644 --- a/drivers/firmware/arm_scmi/sensors.c +++ b/drivers/firmware/arm_scmi/sensors.c @@ -5,7 +5,12 @@ * Copyright (C) 2018 ARM Ltd. */ +#define pr_fmt(fmt) "SCMI Notifications SENSOR - " fmt + +#include <linux/scmi_protocol.h> + #include "common.h" +#include "notify.h" enum scmi_sensor_protocol_cmd { SENSOR_DESCRIPTION_GET = 0x3, @@ -14,10 +19,6 @@ enum scmi_sensor_protocol_cmd { SENSOR_READING_GET = 0x6, }; -enum scmi_sensor_protocol_notify { - SENSOR_TRIP_POINT_EVENT = 0x0, -}; - struct scmi_msg_resp_sensor_attributes { __le16 num_sensors; u8 max_requests; @@ -71,6 +72,12 @@ struct scmi_msg_sensor_reading_get { #define SENSOR_READ_ASYNC BIT(0) }; +struct scmi_sensor_trip_notify_payld { + __le32 agent_id; + __le32 sensor_id; + __le32 trip_point_desc; +}; + struct sensors_info { u32 version; int num_sensors; @@ -271,11 +278,57 @@ static int scmi_sensor_count_get(const struct scmi_handle *handle) static struct scmi_sensor_ops sensor_ops = { .count_get = scmi_sensor_count_get, .info_get = scmi_sensor_info_get, - .trip_point_notify = scmi_sensor_trip_point_notify, .trip_point_config = scmi_sensor_trip_point_config, .reading_get = scmi_sensor_reading_get, }; +static int scmi_sensor_set_notify_enabled(const struct scmi_handle *handle, + u8 evt_id, u32 src_id, bool enable) +{ + int ret; + + ret = scmi_sensor_trip_point_notify(handle, src_id, enable); + if (ret) + pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n", + evt_id, src_id, ret); + + return ret; +} + +static void *scmi_sensor_fill_custom_report(const struct scmi_handle *handle, + u8 evt_id, ktime_t timestamp, + const void *payld, size_t payld_sz, + void *report, u32 *src_id) +{ + const struct scmi_sensor_trip_notify_payld *p = payld; + struct scmi_sensor_trip_point_report *r = report; + + if (evt_id != SCMI_EVENT_SENSOR_TRIP_POINT_EVENT || + sizeof(*p) != payld_sz) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->sensor_id = le32_to_cpu(p->sensor_id); + r->trip_point_desc = le32_to_cpu(p->trip_point_desc); + *src_id = r->sensor_id; + + return r; +} + +static const struct scmi_event sensor_events[] = { + { + .id = SCMI_EVENT_SENSOR_TRIP_POINT_EVENT, + .max_payld_sz = sizeof(struct scmi_sensor_trip_notify_payld), + .max_report_sz = sizeof(struct scmi_sensor_trip_point_report), + }, +}; + +static const struct scmi_event_ops sensor_event_ops = { + .set_notify_enabled = scmi_sensor_set_notify_enabled, + .fill_custom_report = scmi_sensor_fill_custom_report, +}; + static int scmi_sensors_protocol_init(struct scmi_handle *handle) { u32 version; @@ -299,6 +352,12 @@ static int scmi_sensors_protocol_init(struct scmi_handle *handle) scmi_sensor_description_get(handle, sinfo); + scmi_register_protocol_events(handle, + SCMI_PROTOCOL_SENSOR, SCMI_PROTO_QUEUE_SZ, + &sensor_event_ops, sensor_events, + ARRAY_SIZE(sensor_events), + sinfo->num_sensors); + sinfo->version = version; handle->sensor_ops = &sensor_ops; handle->sensor_priv = sinfo; diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c index 49bc4b0e8428..a1537d123e38 100644 --- a/drivers/firmware/arm_scmi/smc.c +++ b/drivers/firmware/arm_scmi/smc.c @@ -21,6 +21,7 @@ * * @cinfo: SCMI channel info * @shmem: Transmit/Receive shared memory area + * @shmem_lock: Lock to protect access to Tx/Rx shared memory area * @func_id: smc/hvc call function id */ diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index ce2f5c28b2df..7e5dd7d1e221 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -9,6 +9,7 @@ #define _LINUX_SCMI_PROTOCOL_H #include <linux/device.h> +#include <linux/notifier.h> #include <linux/types.h> #define SCMI_MAX_STR_SIZE 16 @@ -118,6 +119,8 @@ struct scmi_perf_ops { unsigned long *rate, bool poll); int (*est_power_get)(const struct scmi_handle *handle, u32 domain, unsigned long *rate, unsigned long *power); + bool (*fast_switch_possible)(const struct scmi_handle *handle, + struct device *dev); }; /** @@ -173,18 +176,13 @@ enum scmi_sensor_class { * * @count_get: get the count of sensors provided by SCMI * @info_get: get the information of the specified sensor - * @trip_point_notify: control notifications on cross-over events for - * the trip-points * @trip_point_config: selects and configures a trip-point of interest * @reading_get: gets the current value of the sensor */ struct scmi_sensor_ops { int (*count_get)(const struct scmi_handle *handle); - const struct scmi_sensor_info *(*info_get) (const struct scmi_handle *handle, u32 sensor_id); - int (*trip_point_notify)(const struct scmi_handle *handle, - u32 sensor_id, bool enable); int (*trip_point_config)(const struct scmi_handle *handle, u32 sensor_id, u8 trip_id, u64 trip_value); int (*reading_get)(const struct scmi_handle *handle, u32 sensor_id, @@ -212,6 +210,49 @@ struct scmi_reset_ops { }; /** + * struct scmi_notify_ops - represents notifications' operations provided by + * SCMI core + * @register_event_notifier: Register a notifier_block for the requested event + * @unregister_event_notifier: Unregister a notifier_block for the requested + * event + * + * A user can register/unregister its own notifier_block against the wanted + * platform instance regarding the desired event identified by the + * tuple: (proto_id, evt_id, src_id) using the provided register/unregister + * interface where: + * + * @handle: The handle identifying the platform instance to use + * @proto_id: The protocol ID as in SCMI Specification + * @evt_id: The message ID of the desired event as in SCMI Specification + * @src_id: A pointer to the desired source ID if different sources are + * possible for the protocol (like domain_id, sensor_id...etc) + * + * @src_id can be provided as NULL if it simply does NOT make sense for + * the protocol at hand, OR if the user is explicitly interested in + * receiving notifications from ANY existent source associated to the + * specified proto_id / evt_id. + * + * Received notifications are finally delivered to the registered users, + * invoking the callback provided with the notifier_block *nb as follows: + * + * int user_cb(nb, evt_id, report) + * + * with: + * + * @nb: The notifier block provided by the user + * @evt_id: The message ID of the delivered event + * @report: A custom struct describing the specific event delivered + */ +struct scmi_notify_ops { + int (*register_event_notifier)(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb); + int (*unregister_event_notifier)(const struct scmi_handle *handle, + u8 proto_id, u8 evt_id, u32 *src_id, + struct notifier_block *nb); +}; + +/** * struct scmi_handle - Handle returned to ARM SCMI clients for usage. * * @dev: pointer to the SCMI device @@ -221,6 +262,7 @@ struct scmi_reset_ops { * @clk_ops: pointer to set of clock protocol operations * @sensor_ops: pointer to set of sensor protocol operations * @reset_ops: pointer to set of reset protocol operations + * @notify_ops: pointer to set of notifications related operations * @perf_priv: pointer to private data structure specific to performance * protocol(for internal use only) * @clk_priv: pointer to private data structure specific to clock @@ -231,6 +273,8 @@ struct scmi_reset_ops { * protocol(for internal use only) * @reset_priv: pointer to private data structure specific to reset * protocol(for internal use only) + * @notify_priv: pointer to private data structure specific to notifications + * (for internal use only) */ struct scmi_handle { struct device *dev; @@ -240,12 +284,14 @@ struct scmi_handle { struct scmi_power_ops *power_ops; struct scmi_sensor_ops *sensor_ops; struct scmi_reset_ops *reset_ops; + struct scmi_notify_ops *notify_ops; /* for protocol internal use */ void *perf_priv; void *clk_priv; void *power_priv; void *sensor_priv; void *reset_priv; + void *notify_priv; }; enum scmi_std_protocol { @@ -324,4 +370,58 @@ typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *); int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn); void scmi_protocol_unregister(int protocol_id); +/* SCMI Notification API - Custom Event Reports */ +enum scmi_notification_events { + SCMI_EVENT_POWER_STATE_CHANGED = 0x0, + SCMI_EVENT_PERFORMANCE_LIMITS_CHANGED = 0x0, + SCMI_EVENT_PERFORMANCE_LEVEL_CHANGED = 0x1, + SCMI_EVENT_SENSOR_TRIP_POINT_EVENT = 0x0, + SCMI_EVENT_RESET_ISSUED = 0x0, + SCMI_EVENT_BASE_ERROR_EVENT = 0x0, +}; + +struct scmi_power_state_changed_report { + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int power_state; +}; + +struct scmi_perf_limits_report { + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int range_max; + unsigned int range_min; +}; + +struct scmi_perf_level_report { + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int performance_level; +}; + +struct scmi_sensor_trip_point_report { + ktime_t timestamp; + unsigned int agent_id; + unsigned int sensor_id; + unsigned int trip_point_desc; +}; + +struct scmi_reset_issued_report { + ktime_t timestamp; + unsigned int agent_id; + unsigned int domain_id; + unsigned int reset_state; +}; + +struct scmi_base_error_report { + ktime_t timestamp; + unsigned int agent_id; + bool fatal; + unsigned int cmd_count; + unsigned long long reports[]; +}; + #endif /* _LINUX_SCMI_PROTOCOL_H */ diff --git a/include/trace/events/scmi.h b/include/trace/events/scmi.h index f076c430d243..f3a4b4d60714 100644 --- a/include/trace/events/scmi.h +++ b/include/trace/events/scmi.h @@ -35,7 +35,7 @@ TRACE_EVENT(scmi_xfer_begin, TRACE_EVENT(scmi_xfer_end, TP_PROTO(int transfer_id, u8 msg_id, u8 protocol_id, u16 seq, - u32 status), + int status), TP_ARGS(transfer_id, msg_id, protocol_id, seq, status), TP_STRUCT__entry( @@ -43,7 +43,7 @@ TRACE_EVENT(scmi_xfer_end, __field(u8, msg_id) __field(u8, protocol_id) __field(u16, seq) - __field(u32, status) + __field(int, status) ), TP_fast_assign( @@ -54,7 +54,7 @@ TRACE_EVENT(scmi_xfer_end, __entry->status = status; ), - TP_printk("transfer_id=%d msg_id=%u protocol_id=%u seq=%u status=%u", + TP_printk("transfer_id=%d msg_id=%u protocol_id=%u seq=%u status=%d", __entry->transfer_id, __entry->msg_id, __entry->protocol_id, __entry->seq, __entry->status) ); |