ACPI: PM: s2idle: Move x86-specific code to the x86 directory

Some code in drivers/acpi/sleep.c (which is regarded as a generic
file) related to suspend-to-idle support has grown direct dependencies
on x86, but in fact it has been specific to x86 (which is the only
user of it) anyway for a long time.

For this reason, move that code to a separate file under acpi/x86/
and make it build and run as before under the right conditions.

While at it, rename a vendor checking function in that code and
consistently use acpi_handle_debug() for printing debug-related
information in it.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 460 insertions, 0 deletions

diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
new file mode 100644
index 000000000000..25fea34b544c
--- /dev/null
+++ b/drivers/acpi/x86/s2idle.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Architecture-specific ACPI-based support for suspend-to-idle.
+ *
+ * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ *
+ * On platforms supporting the Low Power S0 Idle interface there is an ACPI
+ * device object with the PNP0D80 compatible device ID (System Power Management
+ * Controller) and a specific _DSM method under it.  That method, if present,
+ * can be used to indicate to the platform that the OS is transitioning into a
+ * low-power state in which certain types of activity are not desirable or that
+ * it is leaving such a state, which allows the platform to adjust its operation
+ * mode accordingly.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/suspend.h>
+
+#include "../sleep.h"
+
+#ifdef CONFIG_SUSPEND
+
+static bool sleep_no_lps0 __read_mostly;
+module_param(sleep_no_lps0, bool, 0644);
+MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
+
+static const struct acpi_device_id lps0_device_ids[] = {
+	{"PNP0D80", },
+	{"", },
+};
+
+#define ACPI_LPS0_DSM_UUID	"c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
+
+#define ACPI_LPS0_GET_DEVICE_CONSTRAINTS	1
+#define ACPI_LPS0_SCREEN_OFF	3
+#define ACPI_LPS0_SCREEN_ON	4
+#define ACPI_LPS0_ENTRY		5
+#define ACPI_LPS0_EXIT		6
+
+/* AMD */
+#define ACPI_LPS0_DSM_UUID_AMD      "e3f32452-febc-43ce-9039-932122d37721"
+#define ACPI_LPS0_SCREEN_OFF_AMD    4
+#define ACPI_LPS0_SCREEN_ON_AMD     5
+
+static acpi_handle lps0_device_handle;
+static guid_t lps0_dsm_guid;
+static char lps0_dsm_func_mask;
+
+/* Device constraint entry structure */
+struct lpi_device_info {
+	char *name;
+	int enabled;
+	union acpi_object *package;
+};
+
+/* Constraint package structure */
+struct lpi_device_constraint {
+	int uid;
+	int min_dstate;
+	int function_states;
+};
+
+struct lpi_constraints {
+	acpi_handle handle;
+	int min_dstate;
+};
+
+/* AMD */
+/* Device constraint entry structure */
+struct lpi_device_info_amd {
+	int revision;
+	int count;
+	union acpi_object *package;
+};
+
+/* Constraint package structure */
+struct lpi_device_constraint_amd {
+	char *name;
+	int enabled;
+	int function_states;
+	int min_dstate;
+};
+
+static struct lpi_constraints *lpi_constraints_table;
+static int lpi_constraints_table_size;
+static int rev_id;
+
+static void lpi_device_get_constraints_amd(void)
+{
+	union acpi_object *out_obj;
+	int i, j, k;
+
+	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
+					  1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
+					  NULL, ACPI_TYPE_PACKAGE);
+
+	if (!out_obj)
+		return;
+
+	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
+			  out_obj ? "successful" : "failed");
+
+	for (i = 0; i < out_obj->package.count; i++) {
+		union acpi_object *package = &out_obj->package.elements[i];
+		struct lpi_device_info_amd info = { };
+
+		if (package->type == ACPI_TYPE_INTEGER) {
+			switch (i) {
+			case 0:
+				info.revision = package->integer.value;
+				break;
+			case 1:
+				info.count = package->integer.value;
+				break;
+			}
+		} else if (package->type == ACPI_TYPE_PACKAGE) {
+			lpi_constraints_table = kcalloc(package->package.count,
+							sizeof(*lpi_constraints_table),
+							GFP_KERNEL);
+
+			if (!lpi_constraints_table)
+				goto free_acpi_buffer;
+
+			acpi_handle_debug(lps0_device_handle,
+					  "LPI: constraints list begin:\n");
+
+			for (j = 0; j < package->package.count; ++j) {
+				union acpi_object *info_obj = &package->package.elements[j];
+				struct lpi_device_constraint_amd dev_info = {};
+				struct lpi_constraints *list;
+				acpi_status status;
+
+				for (k = 0; k < info_obj->package.count; ++k) {
+					union acpi_object *obj = &info_obj->package.elements[k];
+					union acpi_object *obj_new;
+
+					list = &lpi_constraints_table[lpi_constraints_table_size];
+					list->min_dstate = -1;
+
+					obj_new = &obj[k];
+					switch (k) {
+					case 0:
+						dev_info.enabled = obj->integer.value;
+						break;
+					case 1:
+						dev_info.name = obj->string.pointer;
+						break;
+					case 2:
+						dev_info.function_states = obj->integer.value;
+						break;
+					case 3:
+						dev_info.min_dstate = obj->integer.value;
+						break;
+					}
+
+					if (!dev_info.enabled || !dev_info.name ||
+					    !dev_info.min_dstate)
+						continue;
+
+					status = acpi_get_handle(NULL, dev_info.name,
+								 &list->handle);
+					if (ACPI_FAILURE(status))
+						continue;
+
+					acpi_handle_debug(lps0_device_handle,
+							  "Name:%s\n", dev_info.name);
+
+					list->min_dstate = dev_info.min_dstate;
+
+					if (list->min_dstate < 0) {
+						acpi_handle_debug(lps0_device_handle,
+								  "Incomplete constraint defined\n");
+						continue;
+					}
+				}
+				lpi_constraints_table_size++;
+			}
+		}
+	}
+
+	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
+
+free_acpi_buffer:
+	ACPI_FREE(out_obj);
+}
+
+static void lpi_device_get_constraints(void)
+{
+	union acpi_object *out_obj;
+	int i;
+
+	out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
+					  1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
+					  NULL, ACPI_TYPE_PACKAGE);
+
+	acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
+			  out_obj ? "successful" : "failed");
+
+	if (!out_obj)
+		return;
+
+	lpi_constraints_table = kcalloc(out_obj->package.count,
+					sizeof(*lpi_constraints_table),
+					GFP_KERNEL);
+	if (!lpi_constraints_table)
+		goto free_acpi_buffer;
+
+	acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
+
+	for (i = 0; i < out_obj->package.count; i++) {
+		struct lpi_constraints *constraint;
+		acpi_status status;
+		union acpi_object *package = &out_obj->package.elements[i];
+		struct lpi_device_info info = { };
+		int package_count = 0, j;
+
+		if (!package)
+			continue;
+
+		for (j = 0; j < package->package.count; ++j) {
+			union acpi_object *element =
+					&(package->package.elements[j]);
+
+			switch (element->type) {
+			case ACPI_TYPE_INTEGER:
+				info.enabled = element->integer.value;
+				break;
+			case ACPI_TYPE_STRING:
+				info.name = element->string.pointer;
+				break;
+			case ACPI_TYPE_PACKAGE:
+				package_count = element->package.count;
+				info.package = element->package.elements;
+				break;
+			}
+		}
+
+		if (!info.enabled || !info.package || !info.name)
+			continue;
+
+		constraint = &lpi_constraints_table[lpi_constraints_table_size];
+
+		status = acpi_get_handle(NULL, info.name, &constraint->handle);
+		if (ACPI_FAILURE(status))
+			continue;
+
+		acpi_handle_debug(lps0_device_handle,
+				  "index:%d Name:%s\n", i, info.name);
+
+		constraint->min_dstate = -1;
+
+		for (j = 0; j < package_count; ++j) {
+			union acpi_object *info_obj = &info.package[j];
+			union acpi_object *cnstr_pkg;
+			union acpi_object *obj;
+			struct lpi_device_constraint dev_info;
+
+			switch (info_obj->type) {
+			case ACPI_TYPE_INTEGER:
+				/* version */
+				break;
+			case ACPI_TYPE_PACKAGE:
+				if (info_obj->package.count < 2)
+					break;
+
+				cnstr_pkg = info_obj->package.elements;
+				obj = &cnstr_pkg[0];
+				dev_info.uid = obj->integer.value;
+				obj = &cnstr_pkg[1];
+				dev_info.min_dstate = obj->integer.value;
+
+				acpi_handle_debug(lps0_device_handle,
+					"uid:%d min_dstate:%s\n",
+					dev_info.uid,
+					acpi_power_state_string(dev_info.min_dstate));
+
+				constraint->min_dstate = dev_info.min_dstate;
+				break;
+			}
+		}
+
+		if (constraint->min_dstate < 0) {
+			acpi_handle_debug(lps0_device_handle,
+					  "Incomplete constraint defined\n");
+			continue;
+		}
+
+		lpi_constraints_table_size++;
+	}
+
+	acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
+
+free_acpi_buffer:
+	ACPI_FREE(out_obj);
+}
+
+static void lpi_check_constraints(void)
+{
+	int i;
+
+	for (i = 0; i < lpi_constraints_table_size; ++i) {
+		acpi_handle handle = lpi_constraints_table[i].handle;
+		struct acpi_device *adev;
+
+		if (!handle || acpi_bus_get_device(handle, &adev))
+			continue;
+
+		acpi_handle_debug(handle,
+			"LPI: required min power state:%s current power state:%s\n",
+			acpi_power_state_string(lpi_constraints_table[i].min_dstate),
+			acpi_power_state_string(adev->power.state));
+
+		if (!adev->flags.power_manageable) {
+			acpi_handle_info(handle, "LPI: Device not power manageable\n");
+			lpi_constraints_table[i].handle = NULL;
+			continue;
+		}
+
+		if (adev->power.state < lpi_constraints_table[i].min_dstate)
+			acpi_handle_info(handle,
+				"LPI: Constraint not met; min power state:%s current power state:%s\n",
+				acpi_power_state_string(lpi_constraints_table[i].min_dstate),
+				acpi_power_state_string(adev->power.state));
+	}
+}
+
+static void acpi_sleep_run_lps0_dsm(unsigned int func)
+{
+	union acpi_object *out_obj;
+
+	if (!(lps0_dsm_func_mask & (1 << func)))
+		return;
+
+	out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
+	ACPI_FREE(out_obj);
+
+	acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
+			  func, out_obj ? "successful" : "failed");
+}
+
+static bool acpi_s2idle_vendor_amd(void)
+{
+	return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
+}
+
+static int lps0_device_attach(struct acpi_device *adev,
+			      const struct acpi_device_id *not_used)
+{
+	union acpi_object *out_obj;
+
+	if (lps0_device_handle)
+		return 0;
+
+	if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
+		return 0;
+
+	if (acpi_s2idle_vendor_amd()) {
+		guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
+		out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
+		rev_id = 0;
+	} else {
+		guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
+		out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
+		rev_id = 1;
+	}
+
+	/* Check if the _DSM is present and as expected. */
+	if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
+		acpi_handle_debug(adev->handle,
+				  "_DSM function 0 evaluation failed\n");
+		return 0;
+	}
+
+	lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
+
+	ACPI_FREE(out_obj);
+
+	acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
+			  lps0_dsm_func_mask);
+
+	lps0_device_handle = adev->handle;
+
+	if (acpi_s2idle_vendor_amd())
+		lpi_device_get_constraints_amd();
+	else
+		lpi_device_get_constraints();
+
+	/*
+	 * Use suspend-to-idle by default if the default suspend mode was not
+	 * set from the command line.
+	 */
+	if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
+		mem_sleep_current = PM_SUSPEND_TO_IDLE;
+
+	/*
+	 * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
+	 * EC GPE to be enabled while suspended for certain wakeup devices to
+	 * work, so mark it as wakeup-capable.
+	 */
+	acpi_ec_mark_gpe_for_wake();
+
+	return 0;
+}
+
+static struct acpi_scan_handler lps0_handler = {
+	.ids = lps0_device_ids,
+	.attach = lps0_device_attach,
+};
+
+int acpi_s2idle_prepare_late(void)
+{
+	if (!lps0_device_handle || sleep_no_lps0)
+		return 0;
+
+	if (pm_debug_messages_on)
+		lpi_check_constraints();
+
+	if (acpi_s2idle_vendor_amd()) {
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
+	} else {
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
+	}
+
+	return 0;
+}
+
+void acpi_s2idle_restore_early(void)
+{
+	if (!lps0_device_handle || sleep_no_lps0)
+		return;
+
+	if (acpi_s2idle_vendor_amd()) {
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
+	} else {
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
+		acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
+	}
+}
+
+static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
+	.begin = acpi_s2idle_begin,
+	.prepare = acpi_s2idle_prepare,
+	.prepare_late = acpi_s2idle_prepare_late,
+	.wake = acpi_s2idle_wake,
+	.restore_early = acpi_s2idle_restore_early,
+	.restore = acpi_s2idle_restore,
+	.end = acpi_s2idle_end,
+};
+
+void acpi_s2idle_setup(void)
+{
+	acpi_scan_add_handler(&lps0_handler);
+	s2idle_set_ops(&acpi_s2idle_ops_lps0);
+}
+
+#endif /* CONFIG_SUSPEND */