drivers/platform/x86/amd-pmc.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * AMD SoC Power Management Controller Driver
  *
  * Copyright (c) 2020, Advanced Micro Devices, Inc.
  * All Rights Reserved.
  *
  * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/acpi.h>
 #include <linux/bitfield.h>
 #include <linux/bits.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/suspend.h>
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>

 /* SMU communication registers */
 #define AMD_PMC_REGISTER_MESSAGE	0x538
 #define AMD_PMC_REGISTER_RESPONSE	0x980
 #define AMD_PMC_REGISTER_ARGUMENT	0x9BC

 /* Base address of SMU for mapping physical address to virtual address */
 #define AMD_PMC_SMU_INDEX_ADDRESS	0xB8
 #define AMD_PMC_SMU_INDEX_DATA		0xBC
 #define AMD_PMC_MAPPING_SIZE		0x01000
 #define AMD_PMC_BASE_ADDR_OFFSET	0x10000
 #define AMD_PMC_BASE_ADDR_LO		0x13B102E8
 #define AMD_PMC_BASE_ADDR_HI		0x13B102EC
 #define AMD_PMC_BASE_ADDR_LO_MASK	GENMASK(15, 0)
 #define AMD_PMC_BASE_ADDR_HI_MASK	GENMASK(31, 20)

 /* SMU Response Codes */
 #define AMD_PMC_RESULT_OK                    0x01
 #define AMD_PMC_RESULT_CMD_REJECT_BUSY       0xFC
 #define AMD_PMC_RESULT_CMD_REJECT_PREREQ     0xFD
 #define AMD_PMC_RESULT_CMD_UNKNOWN           0xFE
 #define AMD_PMC_RESULT_FAILED                0xFF

 /* FCH SSC Registers */
 #define FCH_S0I3_ENTRY_TIME_L_OFFSET	0x30
 #define FCH_S0I3_ENTRY_TIME_H_OFFSET	0x34
 #define FCH_S0I3_EXIT_TIME_L_OFFSET	0x38
 #define FCH_S0I3_EXIT_TIME_H_OFFSET	0x3C
 #define FCH_SSC_MAPPING_SIZE		0x800
 #define FCH_BASE_PHY_ADDR_LOW		0xFED81100
 #define FCH_BASE_PHY_ADDR_HIGH		0x00000000

 /* SMU Message Definations */
 #define SMU_MSG_GETSMUVERSION		0x02
 #define SMU_MSG_LOG_GETDRAM_ADDR_HI	0x04
 #define SMU_MSG_LOG_GETDRAM_ADDR_LO	0x05
 #define SMU_MSG_LOG_START		0x06
 #define SMU_MSG_LOG_RESET		0x07
 #define SMU_MSG_LOG_DUMP_DATA		0x08
 #define SMU_MSG_GET_SUP_CONSTRAINTS	0x09
 /* List of supported CPU ids */
 #define AMD_CPU_ID_RV			0x15D0
 #define AMD_CPU_ID_RN			0x1630
 #define AMD_CPU_ID_PCO			AMD_CPU_ID_RV
 #define AMD_CPU_ID_CZN			AMD_CPU_ID_RN
 #define AMD_CPU_ID_YC			0x14B5

 #define PMC_MSG_DELAY_MIN_US		100
 #define RESPONSE_REGISTER_LOOP_MAX	200

 #define SOC_SUBSYSTEM_IP_MAX	12
 #define DELAY_MIN_US		2000
 #define DELAY_MAX_US		3000
 enum amd_pmc_def {
 	MSG_TEST = 0x01,
 	MSG_OS_HINT_PCO,
 	MSG_OS_HINT_RN,
 };

 struct amd_pmc_bit_map {
 	const char *name;
 	u32 bit_mask;
 };

 static const struct amd_pmc_bit_map soc15_ip_blk[] = {
 	{"DISPLAY",	BIT(0)},
 	{"CPU",		BIT(1)},
 	{"GFX",		BIT(2)},
 	{"VDD",		BIT(3)},
 	{"ACP",		BIT(4)},
 	{"VCN",		BIT(5)},
 	{"ISP",		BIT(6)},
 	{"NBIO",	BIT(7)},
 	{"DF",		BIT(8)},
 	{"USB0",	BIT(9)},
 	{"USB1",	BIT(10)},
 	{"LAPIC",	BIT(11)},
 	{}
 };

 struct amd_pmc_dev {
 	void __iomem *regbase;
 	void __iomem *smu_virt_addr;
 	void __iomem *fch_virt_addr;
 	u32 base_addr;
 	u32 cpu_id;
 	u32 active_ips;
 	struct device *dev;
 	struct mutex lock; /* generic mutex lock */
 #if IS_ENABLED(CONFIG_DEBUG_FS)
 	struct dentry *dbgfs_dir;
 #endif /* CONFIG_DEBUG_FS */
 };

 static struct amd_pmc_dev pmc;
 static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, bool set, u32 *data, u8 msg, bool ret);

 static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
 {
 	return ioread32(dev->regbase + reg_offset);
 }

 static inline void amd_pmc_reg_write(struct amd_pmc_dev *dev, int reg_offset, u32 val)
 {
 	iowrite32(val, dev->regbase + reg_offset);
 }

 struct smu_metrics {
 	u32 table_version;
 	u32 hint_count;
 	u32 s0i3_cyclecount;
 	u32 timein_s0i2;
 	u64 timeentering_s0i3_lastcapture;
 	u64 timeentering_s0i3_totaltime;
 	u64 timeto_resume_to_os_lastcapture;
 	u64 timeto_resume_to_os_totaltime;
 	u64 timein_s0i3_lastcapture;
 	u64 timein_s0i3_totaltime;
 	u64 timein_swdrips_lastcapture;
 	u64 timein_swdrips_totaltime;
 	u64 timecondition_notmet_lastcapture[SOC_SUBSYSTEM_IP_MAX];
 	u64 timecondition_notmet_totaltime[SOC_SUBSYSTEM_IP_MAX];
 } __packed;

 #ifdef CONFIG_DEBUG_FS
 static int smu_fw_info_show(struct seq_file *s, void *unused)
 {
 	struct amd_pmc_dev *dev = s->private;
 	struct smu_metrics table;
 	int idx;

 	if (dev->cpu_id == AMD_CPU_ID_PCO)
 		return -EINVAL;

 	memcpy_fromio(&table, dev->smu_virt_addr, sizeof(struct smu_metrics));

 	seq_puts(s, "\n=== SMU Statistics ===\n");
 	seq_printf(s, "Table Version: %d\n", table.table_version);
 	seq_printf(s, "Hint Count: %d\n", table.hint_count);
 	seq_printf(s, "S0i3 Cycle Count: %d\n", table.s0i3_cyclecount);
 	seq_printf(s, "Time (in us) to S0i3: %lld\n", table.timeentering_s0i3_lastcapture);
 	seq_printf(s, "Time (in us) in S0i3: %lld\n", table.timein_s0i3_lastcapture);

 	seq_puts(s, "\n=== Active time (in us) ===\n");
 	for (idx = 0 ; idx < SOC_SUBSYSTEM_IP_MAX ; idx++) {
 		if (soc15_ip_blk[idx].bit_mask & dev->active_ips)
 			seq_printf(s, "%-8s : %lld\n", soc15_ip_blk[idx].name,
 				   table.timecondition_notmet_lastcapture[idx]);
 	}

 	return 0;
 }
 DEFINE_SHOW_ATTRIBUTE(smu_fw_info);

 static int s0ix_stats_show(struct seq_file *s, void *unused)
 {
 	struct amd_pmc_dev *dev = s->private;
 	u64 entry_time, exit_time, residency;

 	entry_time = ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_H_OFFSET);
 	entry_time = entry_time << 32 | ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_L_OFFSET);

 	exit_time = ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_H_OFFSET);
 	exit_time = exit_time << 32 | ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_L_OFFSET);

 	/* It's in 48MHz. We need to convert it */
 	residency = exit_time - entry_time;
 	do_div(residency, 48);

 	seq_puts(s, "=== S0ix statistics ===\n");
 	seq_printf(s, "S0ix Entry Time: %lld\n", entry_time);
 	seq_printf(s, "S0ix Exit Time: %lld\n", exit_time);
 	seq_printf(s, "Residency Time: %lld\n", residency);

 	return 0;
 }
 DEFINE_SHOW_ATTRIBUTE(s0ix_stats);

 static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
 {
 	debugfs_remove_recursive(dev->dbgfs_dir);
 }

 static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
 {
 	dev->dbgfs_dir = debugfs_create_dir("amd_pmc", NULL);
 	debugfs_create_file("smu_fw_info", 0644, dev->dbgfs_dir, dev,
 			    &smu_fw_info_fops);
 	debugfs_create_file("s0ix_stats", 0644, dev->dbgfs_dir, dev,
 			    &s0ix_stats_fops);
 }
 #else
 static inline void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
 {
 }

 static inline void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
 {
 }
 #endif /* CONFIG_DEBUG_FS */

 static int amd_pmc_setup_smu_logging(struct amd_pmc_dev *dev)
 {
 	u32 phys_addr_low, phys_addr_hi;
 	u64 smu_phys_addr;

 	if (dev->cpu_id == AMD_CPU_ID_PCO)
 		return -EINVAL;

 	/* Get Active devices list from SMU */
 	amd_pmc_send_cmd(dev, 0, &dev->active_ips, SMU_MSG_GET_SUP_CONSTRAINTS, 1);

 	/* Get dram address */
 	amd_pmc_send_cmd(dev, 0, &phys_addr_low, SMU_MSG_LOG_GETDRAM_ADDR_LO, 1);
 	amd_pmc_send_cmd(dev, 0, &phys_addr_hi, SMU_MSG_LOG_GETDRAM_ADDR_HI, 1);
 	smu_phys_addr = ((u64)phys_addr_hi << 32 | phys_addr_low);

 	dev->smu_virt_addr = devm_ioremap(dev->dev, smu_phys_addr, sizeof(struct smu_metrics));
 	if (!dev->smu_virt_addr)
 		return -ENOMEM;

 	/* Start the logging */
 	amd_pmc_send_cmd(dev, 0, NULL, SMU_MSG_LOG_START, 0);

 	return 0;
 }

 static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
 {
 	u32 value;

 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_RESPONSE);
 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_RESPONSE:%x\n", value);

 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_ARGUMENT:%x\n", value);

 	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_MESSAGE);
 	dev_dbg(dev->dev, "AMD_PMC_REGISTER_MESSAGE:%x\n", value);
 }

 static int amd_pmc_send_cmd(struct amd_pmc_dev *dev, bool set, u32 *data, u8 msg, bool ret)
 {
 	int rc;
 	u32 val;

 	mutex_lock(&dev->lock);
 	/* Wait until we get a valid response */
 	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
 				val, val != 0, PMC_MSG_DELAY_MIN_US,
 				PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
 	if (rc) {
 		dev_err(dev->dev, "failed to talk to SMU\n");
 		goto out_unlock;
 	}

 	/* Write zero to response register */
 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_RESPONSE, 0);

 	/* Write argument into response register */
 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_ARGUMENT, set);

 	/* Write message ID to message ID register */
 	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_MESSAGE, msg);

 	/* Wait until we get a valid response */
 	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
 				val, val != 0, PMC_MSG_DELAY_MIN_US,
 				PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
 	if (rc) {
 		dev_err(dev->dev, "SMU response timed out\n");
 		goto out_unlock;
 	}

 	switch (val) {
 	case AMD_PMC_RESULT_OK:
 		if (ret) {
 			/* PMFW may take longer time to return back the data */
 			usleep_range(DELAY_MIN_US, 10 * DELAY_MAX_US);
 			*data = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
 		}
 		break;
 	case AMD_PMC_RESULT_CMD_REJECT_BUSY:
 		dev_err(dev->dev, "SMU not ready. err: 0x%x\n", val);
 		rc = -EBUSY;
 		goto out_unlock;
 	case AMD_PMC_RESULT_CMD_UNKNOWN:
 		dev_err(dev->dev, "SMU cmd unknown. err: 0x%x\n", val);
 		rc = -EINVAL;
 		goto out_unlock;
 	case AMD_PMC_RESULT_CMD_REJECT_PREREQ:
 	case AMD_PMC_RESULT_FAILED:
 	default:
 		dev_err(dev->dev, "SMU cmd failed. err: 0x%x\n", val);
 		rc = -EIO;
 		goto out_unlock;
 	}

 out_unlock:
 	mutex_unlock(&dev->lock);
 	amd_pmc_dump_registers(dev);
 	return rc;
 }

 static int amd_pmc_get_os_hint(struct amd_pmc_dev *dev)
 {
 	switch (dev->cpu_id) {
 	case AMD_CPU_ID_PCO:
 		return MSG_OS_HINT_PCO;
 	case AMD_CPU_ID_RN:
 	case AMD_CPU_ID_YC:
 		return MSG_OS_HINT_RN;
 	}
 	return -EINVAL;
 }

 static int __maybe_unused amd_pmc_suspend(struct device *dev)
 {
 	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
 	int rc;
 	u8 msg;

 	/* Reset and Start SMU logging - to monitor the s0i3 stats */
 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_RESET, 0);
 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_START, 0);

 	msg = amd_pmc_get_os_hint(pdev);
 	rc = amd_pmc_send_cmd(pdev, 1, NULL, msg, 0);
 	if (rc)
 		dev_err(pdev->dev, "suspend failed\n");

 	return rc;
 }

 static int __maybe_unused amd_pmc_resume(struct device *dev)
 {
 	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
 	int rc;
 	u8 msg;

 	/* Let SMU know that we are looking for stats */
 	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_DUMP_DATA, 0);

 	msg = amd_pmc_get_os_hint(pdev);
 	rc = amd_pmc_send_cmd(pdev, 0, NULL, msg, 0);
 	if (rc)
 		dev_err(pdev->dev, "resume failed\n");

 	return 0;
 }

 static const struct dev_pm_ops amd_pmc_pm_ops = {
 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(amd_pmc_suspend, amd_pmc_resume)
 };

 static const struct pci_device_id pmc_pci_ids[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_YC) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_CZN) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RN) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_PCO) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RV) },
 	{ }
 };

 static int amd_pmc_probe(struct platform_device *pdev)
 {
 	struct amd_pmc_dev *dev = &pmc;
 	struct pci_dev *rdev;
 	u32 base_addr_lo, base_addr_hi;
 	u64 base_addr, fch_phys_addr;
 	int err;
 	u32 val;

 	dev->dev = &pdev->dev;

 	rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
 	if (!rdev || !pci_match_id(pmc_pci_ids, rdev)) {
 		pci_dev_put(rdev);
 		return -ENODEV;
 	}

 	dev->cpu_id = rdev->device;
 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_LO);
 	if (err) {
 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
 		pci_dev_put(rdev);
 		return pcibios_err_to_errno(err);
 	}

 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
 	if (err) {
 		pci_dev_put(rdev);
 		return pcibios_err_to_errno(err);
 	}

 	base_addr_lo = val & AMD_PMC_BASE_ADDR_HI_MASK;

 	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_HI);
 	if (err) {
 		dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
 		pci_dev_put(rdev);
 		return pcibios_err_to_errno(err);
 	}

 	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
 	if (err) {
 		pci_dev_put(rdev);
 		return pcibios_err_to_errno(err);
 	}

 	base_addr_hi = val & AMD_PMC_BASE_ADDR_LO_MASK;
 	pci_dev_put(rdev);
 	base_addr = ((u64)base_addr_hi << 32 | base_addr_lo);

 	dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
 				    AMD_PMC_MAPPING_SIZE);
 	if (!dev->regbase)
 		return -ENOMEM;

 	mutex_init(&dev->lock);

 	/* Use FCH registers to get the S0ix stats */
 	base_addr_lo = FCH_BASE_PHY_ADDR_LOW;
 	base_addr_hi = FCH_BASE_PHY_ADDR_HIGH;
 	fch_phys_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
 	dev->fch_virt_addr = devm_ioremap(dev->dev, fch_phys_addr, FCH_SSC_MAPPING_SIZE);
 	if (!dev->fch_virt_addr)
 		return -ENOMEM;

 	/* Use SMU to get the s0i3 debug stats */
 	err = amd_pmc_setup_smu_logging(dev);
 	if (err)
 		dev_err(dev->dev, "SMU debugging info not supported on this platform\n");

 	platform_set_drvdata(pdev, dev);
 	amd_pmc_dbgfs_register(dev);
 	return 0;
 }

 static int amd_pmc_remove(struct platform_device *pdev)
 {
 	struct amd_pmc_dev *dev = platform_get_drvdata(pdev);

 	amd_pmc_dbgfs_unregister(dev);
 	mutex_destroy(&dev->lock);
 	return 0;
 }

 static const struct acpi_device_id amd_pmc_acpi_ids[] = {
 	{"AMDI0005", 0},
 	{"AMDI0006", 0},
 	{"AMDI0007", 0},
 	{"AMD0004", 0},
 	{ }
 };
 MODULE_DEVICE_TABLE(acpi, amd_pmc_acpi_ids);

 static struct platform_driver amd_pmc_driver = {
 	.driver = {
 		.name = "amd_pmc",
 		.acpi_match_table = amd_pmc_acpi_ids,
 		.pm = &amd_pmc_pm_ops,
 	},
 	.probe = amd_pmc_probe,
 	.remove = amd_pmc_remove,
 };
 module_platform_driver(amd_pmc_driver);

 MODULE_LICENSE("GPL v2");
 MODULE_DESCRIPTION("AMD PMC Driver");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* AMD SoC Power Management Controller Driver
	*
	* Copyright (c) 2020, Advanced Micro Devices, Inc.
	* All Rights Reserved.
	*
	* Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/acpi.h>
	#include <linux/bitfield.h>
	#include <linux/bits.h>
	#include <linux/debugfs.h>
	#include <linux/delay.h>
	#include <linux/io.h>
	#include <linux/iopoll.h>
	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/platform_device.h>
	#include <linux/suspend.h>
	#include <linux/seq_file.h>
	#include <linux/uaccess.h>

	/* SMU communication registers */
	#define AMD_PMC_REGISTER_MESSAGE 0x538
	#define AMD_PMC_REGISTER_RESPONSE 0x980
	#define AMD_PMC_REGISTER_ARGUMENT 0x9BC

	/* Base address of SMU for mapping physical address to virtual address */
	#define AMD_PMC_SMU_INDEX_ADDRESS 0xB8
	#define AMD_PMC_SMU_INDEX_DATA 0xBC
	#define AMD_PMC_MAPPING_SIZE 0x01000
	#define AMD_PMC_BASE_ADDR_OFFSET 0x10000
	#define AMD_PMC_BASE_ADDR_LO 0x13B102E8
	#define AMD_PMC_BASE_ADDR_HI 0x13B102EC
	#define AMD_PMC_BASE_ADDR_LO_MASK GENMASK(15, 0)
	#define AMD_PMC_BASE_ADDR_HI_MASK GENMASK(31, 20)

	/* SMU Response Codes */
	#define AMD_PMC_RESULT_OK 0x01
	#define AMD_PMC_RESULT_CMD_REJECT_BUSY 0xFC
	#define AMD_PMC_RESULT_CMD_REJECT_PREREQ 0xFD
	#define AMD_PMC_RESULT_CMD_UNKNOWN 0xFE
	#define AMD_PMC_RESULT_FAILED 0xFF

	/* FCH SSC Registers */
	#define FCH_S0I3_ENTRY_TIME_L_OFFSET 0x30
	#define FCH_S0I3_ENTRY_TIME_H_OFFSET 0x34
	#define FCH_S0I3_EXIT_TIME_L_OFFSET 0x38
	#define FCH_S0I3_EXIT_TIME_H_OFFSET 0x3C
	#define FCH_SSC_MAPPING_SIZE 0x800
	#define FCH_BASE_PHY_ADDR_LOW 0xFED81100
	#define FCH_BASE_PHY_ADDR_HIGH 0x00000000

	/* SMU Message Definations */
	#define SMU_MSG_GETSMUVERSION 0x02
	#define SMU_MSG_LOG_GETDRAM_ADDR_HI 0x04
	#define SMU_MSG_LOG_GETDRAM_ADDR_LO 0x05
	#define SMU_MSG_LOG_START 0x06
	#define SMU_MSG_LOG_RESET 0x07
	#define SMU_MSG_LOG_DUMP_DATA 0x08
	#define SMU_MSG_GET_SUP_CONSTRAINTS 0x09
	/* List of supported CPU ids */
	#define AMD_CPU_ID_RV 0x15D0
	#define AMD_CPU_ID_RN 0x1630
	#define AMD_CPU_ID_PCO AMD_CPU_ID_RV
	#define AMD_CPU_ID_CZN AMD_CPU_ID_RN
	#define AMD_CPU_ID_YC 0x14B5

	#define PMC_MSG_DELAY_MIN_US 100
	#define RESPONSE_REGISTER_LOOP_MAX 200

	#define SOC_SUBSYSTEM_IP_MAX 12
	#define DELAY_MIN_US 2000
	#define DELAY_MAX_US 3000
	enum amd_pmc_def {
	MSG_TEST = 0x01,
	MSG_OS_HINT_PCO,
	MSG_OS_HINT_RN,
	};

	struct amd_pmc_bit_map {
	const char *name;
	u32 bit_mask;
	};

	static const struct amd_pmc_bit_map soc15_ip_blk[] = {
	{"DISPLAY", BIT(0)},
	{"CPU", BIT(1)},
	{"GFX", BIT(2)},
	{"VDD", BIT(3)},
	{"ACP", BIT(4)},
	{"VCN", BIT(5)},
	{"ISP", BIT(6)},
	{"NBIO", BIT(7)},
	{"DF", BIT(8)},
	{"USB0", BIT(9)},
	{"USB1", BIT(10)},
	{"LAPIC", BIT(11)},
	{}
	};

	struct amd_pmc_dev {
	void __iomem *regbase;
	void __iomem *smu_virt_addr;
	void __iomem *fch_virt_addr;
	u32 base_addr;
	u32 cpu_id;
	u32 active_ips;
	struct device *dev;
	struct mutex lock; /* generic mutex lock */
	#if IS_ENABLED(CONFIG_DEBUG_FS)
	struct dentry *dbgfs_dir;
	#endif /* CONFIG_DEBUG_FS */
	};

	static struct amd_pmc_dev pmc;
	static int amd_pmc_send_cmd(struct amd_pmc_dev dev, bool set, u32 data, u8 msg, bool ret);

	static inline u32 amd_pmc_reg_read(struct amd_pmc_dev *dev, int reg_offset)
	{
	return ioread32(dev->regbase + reg_offset);
	}

	static inline void amd_pmc_reg_write(struct amd_pmc_dev *dev, int reg_offset, u32 val)
	{
	iowrite32(val, dev->regbase + reg_offset);
	}

	struct smu_metrics {
	u32 table_version;
	u32 hint_count;
	u32 s0i3_cyclecount;
	u32 timein_s0i2;
	u64 timeentering_s0i3_lastcapture;
	u64 timeentering_s0i3_totaltime;
	u64 timeto_resume_to_os_lastcapture;
	u64 timeto_resume_to_os_totaltime;
	u64 timein_s0i3_lastcapture;
	u64 timein_s0i3_totaltime;
	u64 timein_swdrips_lastcapture;
	u64 timein_swdrips_totaltime;
	u64 timecondition_notmet_lastcapture[SOC_SUBSYSTEM_IP_MAX];
	u64 timecondition_notmet_totaltime[SOC_SUBSYSTEM_IP_MAX];
	} __packed;

	#ifdef CONFIG_DEBUG_FS
	static int smu_fw_info_show(struct seq_file s, void unused)
	{
	struct amd_pmc_dev *dev = s->private;
	struct smu_metrics table;
	int idx;

	if (dev->cpu_id == AMD_CPU_ID_PCO)
	return -EINVAL;

	memcpy_fromio(&table, dev->smu_virt_addr, sizeof(struct smu_metrics));

	seq_puts(s, "\n=== SMU Statistics ===\n");
	seq_printf(s, "Table Version: %d\n", table.table_version);
	seq_printf(s, "Hint Count: %d\n", table.hint_count);
	seq_printf(s, "S0i3 Cycle Count: %d\n", table.s0i3_cyclecount);
	seq_printf(s, "Time (in us) to S0i3: %lld\n", table.timeentering_s0i3_lastcapture);
	seq_printf(s, "Time (in us) in S0i3: %lld\n", table.timein_s0i3_lastcapture);

	seq_puts(s, "\n=== Active time (in us) ===\n");
	for (idx = 0 ; idx < SOC_SUBSYSTEM_IP_MAX ; idx++) {
	if (soc15_ip_blk[idx].bit_mask & dev->active_ips)
	seq_printf(s, "%-8s : %lld\n", soc15_ip_blk[idx].name,
	table.timecondition_notmet_lastcapture[idx]);
	}

	return 0;
	}
	DEFINE_SHOW_ATTRIBUTE(smu_fw_info);

	static int s0ix_stats_show(struct seq_file s, void unused)
	{
	struct amd_pmc_dev *dev = s->private;
	u64 entry_time, exit_time, residency;

	entry_time = ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_H_OFFSET);
	entry_time = entry_time << 32 \| ioread32(dev->fch_virt_addr + FCH_S0I3_ENTRY_TIME_L_OFFSET);

	exit_time = ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_H_OFFSET);
	exit_time = exit_time << 32 \| ioread32(dev->fch_virt_addr + FCH_S0I3_EXIT_TIME_L_OFFSET);

	/* It's in 48MHz. We need to convert it */
	residency = exit_time - entry_time;
	do_div(residency, 48);

	seq_puts(s, "=== S0ix statistics ===\n");
	seq_printf(s, "S0ix Entry Time: %lld\n", entry_time);
	seq_printf(s, "S0ix Exit Time: %lld\n", exit_time);
	seq_printf(s, "Residency Time: %lld\n", residency);

	return 0;
	}
	DEFINE_SHOW_ATTRIBUTE(s0ix_stats);

	static void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
	{
	debugfs_remove_recursive(dev->dbgfs_dir);
	}

	static void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
	{
	dev->dbgfs_dir = debugfs_create_dir("amd_pmc", NULL);
	debugfs_create_file("smu_fw_info", 0644, dev->dbgfs_dir, dev,
	&smu_fw_info_fops);
	debugfs_create_file("s0ix_stats", 0644, dev->dbgfs_dir, dev,
	&s0ix_stats_fops);
	}
	#else
	static inline void amd_pmc_dbgfs_register(struct amd_pmc_dev *dev)
	{
	}

	static inline void amd_pmc_dbgfs_unregister(struct amd_pmc_dev *dev)
	{
	}
	#endif /* CONFIG_DEBUG_FS */

	static int amd_pmc_setup_smu_logging(struct amd_pmc_dev *dev)
	{
	u32 phys_addr_low, phys_addr_hi;
	u64 smu_phys_addr;

	if (dev->cpu_id == AMD_CPU_ID_PCO)
	return -EINVAL;

	/* Get Active devices list from SMU */
	amd_pmc_send_cmd(dev, 0, &dev->active_ips, SMU_MSG_GET_SUP_CONSTRAINTS, 1);

	/* Get dram address */
	amd_pmc_send_cmd(dev, 0, &phys_addr_low, SMU_MSG_LOG_GETDRAM_ADDR_LO, 1);
	amd_pmc_send_cmd(dev, 0, &phys_addr_hi, SMU_MSG_LOG_GETDRAM_ADDR_HI, 1);
	smu_phys_addr = ((u64)phys_addr_hi << 32 \| phys_addr_low);

	dev->smu_virt_addr = devm_ioremap(dev->dev, smu_phys_addr, sizeof(struct smu_metrics));
	if (!dev->smu_virt_addr)
	return -ENOMEM;

	/* Start the logging */
	amd_pmc_send_cmd(dev, 0, NULL, SMU_MSG_LOG_START, 0);

	return 0;
	}

	static void amd_pmc_dump_registers(struct amd_pmc_dev *dev)
	{
	u32 value;

	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_RESPONSE);
	dev_dbg(dev->dev, "AMD_PMC_REGISTER_RESPONSE:%x\n", value);

	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
	dev_dbg(dev->dev, "AMD_PMC_REGISTER_ARGUMENT:%x\n", value);

	value = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_MESSAGE);
	dev_dbg(dev->dev, "AMD_PMC_REGISTER_MESSAGE:%x\n", value);
	}

	static int amd_pmc_send_cmd(struct amd_pmc_dev dev, bool set, u32 data, u8 msg, bool ret)
	{
	int rc;
	u32 val;

	mutex_lock(&dev->lock);
	/* Wait until we get a valid response */
	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
	val, val != 0, PMC_MSG_DELAY_MIN_US,
	PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
	if (rc) {
	dev_err(dev->dev, "failed to talk to SMU\n");
	goto out_unlock;
	}

	/* Write zero to response register */
	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_RESPONSE, 0);

	/* Write argument into response register */
	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_ARGUMENT, set);

	/* Write message ID to message ID register */
	amd_pmc_reg_write(dev, AMD_PMC_REGISTER_MESSAGE, msg);

	/* Wait until we get a valid response */
	rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMC_REGISTER_RESPONSE,
	val, val != 0, PMC_MSG_DELAY_MIN_US,
	PMC_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
	if (rc) {
	dev_err(dev->dev, "SMU response timed out\n");
	goto out_unlock;
	}

	switch (val) {
	case AMD_PMC_RESULT_OK:
	if (ret) {
	/* PMFW may take longer time to return back the data */
	usleep_range(DELAY_MIN_US, 10 * DELAY_MAX_US);
	*data = amd_pmc_reg_read(dev, AMD_PMC_REGISTER_ARGUMENT);
	}
	break;
	case AMD_PMC_RESULT_CMD_REJECT_BUSY:
	dev_err(dev->dev, "SMU not ready. err: 0x%x\n", val);
	rc = -EBUSY;
	goto out_unlock;
	case AMD_PMC_RESULT_CMD_UNKNOWN:
	dev_err(dev->dev, "SMU cmd unknown. err: 0x%x\n", val);
	rc = -EINVAL;
	goto out_unlock;
	case AMD_PMC_RESULT_CMD_REJECT_PREREQ:
	case AMD_PMC_RESULT_FAILED:
	default:
	dev_err(dev->dev, "SMU cmd failed. err: 0x%x\n", val);
	rc = -EIO;
	goto out_unlock;
	}

	out_unlock:
	mutex_unlock(&dev->lock);
	amd_pmc_dump_registers(dev);
	return rc;
	}

	static int amd_pmc_get_os_hint(struct amd_pmc_dev *dev)
	{
	switch (dev->cpu_id) {
	case AMD_CPU_ID_PCO:
	return MSG_OS_HINT_PCO;
	case AMD_CPU_ID_RN:
	case AMD_CPU_ID_YC:
	return MSG_OS_HINT_RN;
	}
	return -EINVAL;
	}

	static int __maybe_unused amd_pmc_suspend(struct device *dev)
	{
	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
	int rc;
	u8 msg;

	/* Reset and Start SMU logging - to monitor the s0i3 stats */
	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_RESET, 0);
	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_START, 0);

	msg = amd_pmc_get_os_hint(pdev);
	rc = amd_pmc_send_cmd(pdev, 1, NULL, msg, 0);
	if (rc)
	dev_err(pdev->dev, "suspend failed\n");

	return rc;
	}

	static int __maybe_unused amd_pmc_resume(struct device *dev)
	{
	struct amd_pmc_dev *pdev = dev_get_drvdata(dev);
	int rc;
	u8 msg;

	/* Let SMU know that we are looking for stats */
	amd_pmc_send_cmd(pdev, 0, NULL, SMU_MSG_LOG_DUMP_DATA, 0);

	msg = amd_pmc_get_os_hint(pdev);
	rc = amd_pmc_send_cmd(pdev, 0, NULL, msg, 0);
	if (rc)
	dev_err(pdev->dev, "resume failed\n");

	return 0;
	}

	static const struct dev_pm_ops amd_pmc_pm_ops = {
	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(amd_pmc_suspend, amd_pmc_resume)
	};

	static const struct pci_device_id pmc_pci_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_YC) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_CZN) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RN) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_PCO) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_RV) },
	{ }
	};

	static int amd_pmc_probe(struct platform_device *pdev)
	{
	struct amd_pmc_dev *dev = &pmc;
	struct pci_dev *rdev;
	u32 base_addr_lo, base_addr_hi;
	u64 base_addr, fch_phys_addr;
	int err;
	u32 val;

	dev->dev = &pdev->dev;

	rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
	if (!rdev \|\| !pci_match_id(pmc_pci_ids, rdev)) {
	pci_dev_put(rdev);
	return -ENODEV;
	}

	dev->cpu_id = rdev->device;
	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_LO);
	if (err) {
	dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
	pci_dev_put(rdev);
	return pcibios_err_to_errno(err);
	}

	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
	if (err) {
	pci_dev_put(rdev);
	return pcibios_err_to_errno(err);
	}

	base_addr_lo = val & AMD_PMC_BASE_ADDR_HI_MASK;

	err = pci_write_config_dword(rdev, AMD_PMC_SMU_INDEX_ADDRESS, AMD_PMC_BASE_ADDR_HI);
	if (err) {
	dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMC_SMU_INDEX_ADDRESS);
	pci_dev_put(rdev);
	return pcibios_err_to_errno(err);
	}

	err = pci_read_config_dword(rdev, AMD_PMC_SMU_INDEX_DATA, &val);
	if (err) {
	pci_dev_put(rdev);
	return pcibios_err_to_errno(err);
	}

	base_addr_hi = val & AMD_PMC_BASE_ADDR_LO_MASK;
	pci_dev_put(rdev);
	base_addr = ((u64)base_addr_hi << 32 \| base_addr_lo);

	dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMC_BASE_ADDR_OFFSET,
	AMD_PMC_MAPPING_SIZE);
	if (!dev->regbase)
	return -ENOMEM;

	mutex_init(&dev->lock);

	/* Use FCH registers to get the S0ix stats */
	base_addr_lo = FCH_BASE_PHY_ADDR_LOW;
	base_addr_hi = FCH_BASE_PHY_ADDR_HIGH;
	fch_phys_addr = ((u64)base_addr_hi << 32 \| base_addr_lo);
	dev->fch_virt_addr = devm_ioremap(dev->dev, fch_phys_addr, FCH_SSC_MAPPING_SIZE);
	if (!dev->fch_virt_addr)
	return -ENOMEM;

	/* Use SMU to get the s0i3 debug stats */
	err = amd_pmc_setup_smu_logging(dev);
	if (err)
	dev_err(dev->dev, "SMU debugging info not supported on this platform\n");

	platform_set_drvdata(pdev, dev);
	amd_pmc_dbgfs_register(dev);
	return 0;
	}

	static int amd_pmc_remove(struct platform_device *pdev)
	{
	struct amd_pmc_dev *dev = platform_get_drvdata(pdev);

	amd_pmc_dbgfs_unregister(dev);
	mutex_destroy(&dev->lock);
	return 0;
	}

	static const struct acpi_device_id amd_pmc_acpi_ids[] = {
	{"AMDI0005", 0},
	{"AMDI0006", 0},
	{"AMDI0007", 0},
	{"AMD0004", 0},
	{ }
	};
	MODULE_DEVICE_TABLE(acpi, amd_pmc_acpi_ids);

	static struct platform_driver amd_pmc_driver = {
	.driver = {
	.name = "amd_pmc",
	.acpi_match_table = amd_pmc_acpi_ids,
	.pm = &amd_pmc_pm_ops,
	},
	.probe = amd_pmc_probe,
	.remove = amd_pmc_remove,
	};
	module_platform_driver(amd_pmc_driver);

	MODULE_LICENSE("GPL v2");
	MODULE_DESCRIPTION("AMD PMC Driver");