diff options
Diffstat (limited to 'drivers/acpi')
-rw-r--r-- | drivers/acpi/arm64/Kconfig | 3 | ||||
-rw-r--r-- | drivers/acpi/arm64/Makefile | 1 | ||||
-rw-r--r-- | drivers/acpi/arm64/gtdt.c | 417 |
3 files changed, 421 insertions, 0 deletions
diff --git a/drivers/acpi/arm64/Kconfig b/drivers/acpi/arm64/Kconfig index 4616da4c15be..5a6f80fce0d6 100644 --- a/drivers/acpi/arm64/Kconfig +++ b/drivers/acpi/arm64/Kconfig @@ -4,3 +4,6 @@ config ACPI_IORT bool + +config ACPI_GTDT + bool diff --git a/drivers/acpi/arm64/Makefile b/drivers/acpi/arm64/Makefile index 72331f2ce0e9..1017def2ea12 100644 --- a/drivers/acpi/arm64/Makefile +++ b/drivers/acpi/arm64/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_ACPI_IORT) += iort.o +obj-$(CONFIG_ACPI_GTDT) += gtdt.o diff --git a/drivers/acpi/arm64/gtdt.c b/drivers/acpi/arm64/gtdt.c new file mode 100644 index 000000000000..597a737d538f --- /dev/null +++ b/drivers/acpi/arm64/gtdt.c @@ -0,0 +1,417 @@ +/* + * ARM Specific GTDT table Support + * + * Copyright (C) 2016, Linaro Ltd. + * Author: Daniel Lezcano <daniel.lezcano@linaro.org> + * Fu Wei <fu.wei@linaro.org> + * Hanjun Guo <hanjun.guo@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/acpi.h> +#include <linux/init.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> + +#include <clocksource/arm_arch_timer.h> + +#undef pr_fmt +#define pr_fmt(fmt) "ACPI GTDT: " fmt + +/** + * struct acpi_gtdt_descriptor - Store the key info of GTDT for all functions + * @gtdt: The pointer to the struct acpi_table_gtdt of GTDT table. + * @gtdt_end: The pointer to the end of GTDT table. + * @platform_timer: The pointer to the start of Platform Timer Structure + * + * The struct store the key info of GTDT table, it should be initialized by + * acpi_gtdt_init. + */ +struct acpi_gtdt_descriptor { + struct acpi_table_gtdt *gtdt; + void *gtdt_end; + void *platform_timer; +}; + +static struct acpi_gtdt_descriptor acpi_gtdt_desc __initdata; + +static inline void *next_platform_timer(void *platform_timer) +{ + struct acpi_gtdt_header *gh = platform_timer; + + platform_timer += gh->length; + if (platform_timer < acpi_gtdt_desc.gtdt_end) + return platform_timer; + + return NULL; +} + +#define for_each_platform_timer(_g) \ + for (_g = acpi_gtdt_desc.platform_timer; _g; \ + _g = next_platform_timer(_g)) + +static inline bool is_timer_block(void *platform_timer) +{ + struct acpi_gtdt_header *gh = platform_timer; + + return gh->type == ACPI_GTDT_TYPE_TIMER_BLOCK; +} + +static inline bool is_non_secure_watchdog(void *platform_timer) +{ + struct acpi_gtdt_header *gh = platform_timer; + struct acpi_gtdt_watchdog *wd = platform_timer; + + if (gh->type != ACPI_GTDT_TYPE_WATCHDOG) + return false; + + return !(wd->timer_flags & ACPI_GTDT_WATCHDOG_SECURE); +} + +static int __init map_gt_gsi(u32 interrupt, u32 flags) +{ + int trigger, polarity; + + trigger = (flags & ACPI_GTDT_INTERRUPT_MODE) ? ACPI_EDGE_SENSITIVE + : ACPI_LEVEL_SENSITIVE; + + polarity = (flags & ACPI_GTDT_INTERRUPT_POLARITY) ? ACPI_ACTIVE_LOW + : ACPI_ACTIVE_HIGH; + + return acpi_register_gsi(NULL, interrupt, trigger, polarity); +} + +/** + * acpi_gtdt_map_ppi() - Map the PPIs of per-cpu arch_timer. + * @type: the type of PPI. + * + * Note: Secure state is not managed by the kernel on ARM64 systems. + * So we only handle the non-secure timer PPIs, + * ARCH_TIMER_PHYS_SECURE_PPI is treated as invalid type. + * + * Return: the mapped PPI value, 0 if error. + */ +int __init acpi_gtdt_map_ppi(int type) +{ + struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; + + switch (type) { + case ARCH_TIMER_PHYS_NONSECURE_PPI: + return map_gt_gsi(gtdt->non_secure_el1_interrupt, + gtdt->non_secure_el1_flags); + case ARCH_TIMER_VIRT_PPI: + return map_gt_gsi(gtdt->virtual_timer_interrupt, + gtdt->virtual_timer_flags); + + case ARCH_TIMER_HYP_PPI: + return map_gt_gsi(gtdt->non_secure_el2_interrupt, + gtdt->non_secure_el2_flags); + default: + pr_err("Failed to map timer interrupt: invalid type.\n"); + } + + return 0; +} + +/** + * acpi_gtdt_c3stop() - Got c3stop info from GTDT according to the type of PPI. + * @type: the type of PPI. + * + * Return: true if the timer HW state is lost when a CPU enters an idle state, + * false otherwise + */ +bool __init acpi_gtdt_c3stop(int type) +{ + struct acpi_table_gtdt *gtdt = acpi_gtdt_desc.gtdt; + + switch (type) { + case ARCH_TIMER_PHYS_NONSECURE_PPI: + return !(gtdt->non_secure_el1_flags & ACPI_GTDT_ALWAYS_ON); + + case ARCH_TIMER_VIRT_PPI: + return !(gtdt->virtual_timer_flags & ACPI_GTDT_ALWAYS_ON); + + case ARCH_TIMER_HYP_PPI: + return !(gtdt->non_secure_el2_flags & ACPI_GTDT_ALWAYS_ON); + + default: + pr_err("Failed to get c3stop info: invalid type.\n"); + } + + return false; +} + +/** + * acpi_gtdt_init() - Get the info of GTDT table to prepare for further init. + * @table: The pointer to GTDT table. + * @platform_timer_count: It points to a integer variable which is used + * for storing the number of platform timers. + * This pointer could be NULL, if the caller + * doesn't need this info. + * + * Return: 0 if success, -EINVAL if error. + */ +int __init acpi_gtdt_init(struct acpi_table_header *table, + int *platform_timer_count) +{ + void *platform_timer; + struct acpi_table_gtdt *gtdt; + + gtdt = container_of(table, struct acpi_table_gtdt, header); + acpi_gtdt_desc.gtdt = gtdt; + acpi_gtdt_desc.gtdt_end = (void *)table + table->length; + acpi_gtdt_desc.platform_timer = NULL; + if (platform_timer_count) + *platform_timer_count = 0; + + if (table->revision < 2) { + pr_warn("Revision:%d doesn't support Platform Timers.\n", + table->revision); + return 0; + } + + if (!gtdt->platform_timer_count) { + pr_debug("No Platform Timer.\n"); + return 0; + } + + platform_timer = (void *)gtdt + gtdt->platform_timer_offset; + if (platform_timer < (void *)table + sizeof(struct acpi_table_gtdt)) { + pr_err(FW_BUG "invalid timer data.\n"); + return -EINVAL; + } + acpi_gtdt_desc.platform_timer = platform_timer; + if (platform_timer_count) + *platform_timer_count = gtdt->platform_timer_count; + + return 0; +} + +static int __init gtdt_parse_timer_block(struct acpi_gtdt_timer_block *block, + struct arch_timer_mem *timer_mem) +{ + int i; + struct arch_timer_mem_frame *frame; + struct acpi_gtdt_timer_entry *gtdt_frame; + + if (!block->timer_count) { + pr_err(FW_BUG "GT block present, but frame count is zero."); + return -ENODEV; + } + + if (block->timer_count > ARCH_TIMER_MEM_MAX_FRAMES) { + pr_err(FW_BUG "GT block lists %d frames, ACPI spec only allows 8\n", + block->timer_count); + return -EINVAL; + } + + timer_mem->cntctlbase = (phys_addr_t)block->block_address; + /* + * The CNTCTLBase frame is 4KB (register offsets 0x000 - 0xFFC). + * See ARM DDI 0487A.k_iss10775, page I1-5129, Table I1-3 + * "CNTCTLBase memory map". + */ + timer_mem->size = SZ_4K; + + gtdt_frame = (void *)block + block->timer_offset; + if (gtdt_frame + block->timer_count != (void *)block + block->header.length) + return -EINVAL; + + /* + * Get the GT timer Frame data for every GT Block Timer + */ + for (i = 0; i < block->timer_count; i++, gtdt_frame++) { + if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER) + continue; + if (gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES || + !gtdt_frame->base_address || !gtdt_frame->timer_interrupt) + goto error; + + frame = &timer_mem->frame[gtdt_frame->frame_number]; + + /* duplicate frame */ + if (frame->valid) + goto error; + + frame->phys_irq = map_gt_gsi(gtdt_frame->timer_interrupt, + gtdt_frame->timer_flags); + if (frame->phys_irq <= 0) { + pr_warn("failed to map physical timer irq in frame %d.\n", + gtdt_frame->frame_number); + goto error; + } + + if (gtdt_frame->virtual_timer_interrupt) { + frame->virt_irq = + map_gt_gsi(gtdt_frame->virtual_timer_interrupt, + gtdt_frame->virtual_timer_flags); + if (frame->virt_irq <= 0) { + pr_warn("failed to map virtual timer irq in frame %d.\n", + gtdt_frame->frame_number); + goto error; + } + } else { + pr_debug("virtual timer in frame %d not implemented.\n", + gtdt_frame->frame_number); + } + + frame->cntbase = gtdt_frame->base_address; + /* + * The CNTBaseN frame is 4KB (register offsets 0x000 - 0xFFC). + * See ARM DDI 0487A.k_iss10775, page I1-5130, Table I1-4 + * "CNTBaseN memory map". + */ + frame->size = SZ_4K; + frame->valid = true; + } + + return 0; + +error: + do { + if (gtdt_frame->common_flags & ACPI_GTDT_GT_IS_SECURE_TIMER || + gtdt_frame->frame_number >= ARCH_TIMER_MEM_MAX_FRAMES) + continue; + + frame = &timer_mem->frame[gtdt_frame->frame_number]; + + if (frame->phys_irq > 0) + acpi_unregister_gsi(gtdt_frame->timer_interrupt); + frame->phys_irq = 0; + + if (frame->virt_irq > 0) + acpi_unregister_gsi(gtdt_frame->virtual_timer_interrupt); + frame->virt_irq = 0; + } while (i-- >= 0 && gtdt_frame--); + + return -EINVAL; +} + +/** + * acpi_arch_timer_mem_init() - Get the info of all GT blocks in GTDT table. + * @timer_mem: The pointer to the array of struct arch_timer_mem for returning + * the result of parsing. The element number of this array should + * be platform_timer_count(the total number of platform timers). + * @timer_count: It points to a integer variable which is used for storing the + * number of GT blocks we have parsed. + * + * Return: 0 if success, -EINVAL/-ENODEV if error. + */ +int __init acpi_arch_timer_mem_init(struct arch_timer_mem *timer_mem, + int *timer_count) +{ + int ret; + void *platform_timer; + + *timer_count = 0; + for_each_platform_timer(platform_timer) { + if (is_timer_block(platform_timer)) { + ret = gtdt_parse_timer_block(platform_timer, timer_mem); + if (ret) + return ret; + timer_mem++; + (*timer_count)++; + } + } + + if (*timer_count) + pr_info("found %d memory-mapped timer block(s).\n", + *timer_count); + + return 0; +} + +/* + * Initialize a SBSA generic Watchdog platform device info from GTDT + */ +static int __init gtdt_import_sbsa_gwdt(struct acpi_gtdt_watchdog *wd, + int index) +{ + struct platform_device *pdev; + int irq = map_gt_gsi(wd->timer_interrupt, wd->timer_flags); + + /* + * According to SBSA specification the size of refresh and control + * frames of SBSA Generic Watchdog is SZ_4K(Offset 0x000 – 0xFFF). + */ + struct resource res[] = { + DEFINE_RES_MEM(wd->control_frame_address, SZ_4K), + DEFINE_RES_MEM(wd->refresh_frame_address, SZ_4K), + DEFINE_RES_IRQ(irq), + }; + int nr_res = ARRAY_SIZE(res); + + pr_debug("found a Watchdog (0x%llx/0x%llx gsi:%u flags:0x%x).\n", + wd->refresh_frame_address, wd->control_frame_address, + wd->timer_interrupt, wd->timer_flags); + + if (!(wd->refresh_frame_address && wd->control_frame_address)) { + pr_err(FW_BUG "failed to get the Watchdog base address.\n"); + acpi_unregister_gsi(wd->timer_interrupt); + return -EINVAL; + } + + if (irq <= 0) { + pr_warn("failed to map the Watchdog interrupt.\n"); + nr_res--; + } + + /* + * Add a platform device named "sbsa-gwdt" to match the platform driver. + * "sbsa-gwdt": SBSA(Server Base System Architecture) Generic Watchdog + * The platform driver can get device info below by matching this name. + */ + pdev = platform_device_register_simple("sbsa-gwdt", index, res, nr_res); + if (IS_ERR(pdev)) { + acpi_unregister_gsi(wd->timer_interrupt); + return PTR_ERR(pdev); + } + + return 0; +} + +static int __init gtdt_sbsa_gwdt_init(void) +{ + void *platform_timer; + struct acpi_table_header *table; + int ret, timer_count, gwdt_count = 0; + + if (acpi_disabled) + return 0; + + if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_GTDT, 0, &table))) + return -EINVAL; + + /* + * Note: Even though the global variable acpi_gtdt_desc has been + * initialized by acpi_gtdt_init() while initializing the arch timers, + * when we call this function to get SBSA watchdogs info from GTDT, the + * pointers stashed in it are stale (since they are early temporary + * mappings carried out before acpi_permanent_mmap is set) and we need + * to re-initialize them with permanent mapped pointer values to let the + * GTDT parsing possible. + */ + ret = acpi_gtdt_init(table, &timer_count); + if (ret || !timer_count) + return ret; + + for_each_platform_timer(platform_timer) { + if (is_non_secure_watchdog(platform_timer)) { + ret = gtdt_import_sbsa_gwdt(platform_timer, gwdt_count); + if (ret) + break; + gwdt_count++; + } + } + + if (gwdt_count) + pr_info("found %d SBSA generic Watchdog(s).\n", gwdt_count); + + return ret; +} + +device_initcall(gtdt_sbsa_gwdt_init); |