x86/platform/intel-mid: Add Power Management Unit driver (5823d089) · Commits · 戴 / test

arch/x86/include/asm/intel-mid.h

+8 −0

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		@@ -12,9 +12,17 @@
		#define _ASM_X86_INTEL_MID_H

		#include <linux/sfi.h>
		#include <linux/pci.h>
		#include <linux/platform_device.h>

		extern int intel_mid_pci_init(void);
		extern int intel_mid_pci_set_power_state(struct pci_dev *pdev, pci_power_t state);

		#define INTEL_MID_PWR_LSS_OFFSET 4
		#define INTEL_MID_PWR_LSS_TYPE (1 << 7)

		extern int intel_mid_pwr_get_lss_id(struct pci_dev *pdev);

		extern int get_gpio_by_name(const char *name);
		extern void intel_scu_device_register(struct platform_device *pdev);
		extern int __init sfi_parse_mrtc(struct sfi_table_header *table);

arch/x86/pci/intel_mid_pci.c

+35 −5

Original line number	Diff line number	Diff line
		@@ -316,14 +316,44 @@ static void pci_d3delay_fixup(struct pci_dev *dev)
		}
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, pci_d3delay_fixup);

		static void mrst_power_off_unused_dev(struct pci_dev *dev)
		static void mid_power_off_dev(struct pci_dev *dev)
		{
		u16 pmcsr;

		/*
		* Update current state first, otherwise PCI core enforces PCI_D0 in
		* pci_set_power_state() for devices which status was PCI_UNKNOWN.
		*/
		pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
		dev->current_state = (pci_power_t __force)(pmcsr & PCI_PM_CTRL_STATE_MASK);

		pci_set_power_state(dev, PCI_D3hot);
		}
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0801, mrst_power_off_unused_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0809, mrst_power_off_unused_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x080C, mrst_power_off_unused_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0815, mrst_power_off_unused_dev);

		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0801, mid_power_off_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0809, mid_power_off_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x080C, mid_power_off_dev);
		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, 0x0815, mid_power_off_dev);

		static void mrfld_power_off_dev(struct pci_dev *dev)
		{
		int id;

		if (!pci_soc_mode)
		return;

		id = intel_mid_pwr_get_lss_id(dev);
		if (id < 0)
		return;

		/*
		* This sets only PMCSR bits. The actual power off will happen in
		* arch/x86/platform/intel-mid/pwr.c.
		*/
		mid_power_off_dev(dev);
		}

		DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, mrfld_power_off_dev);

		/*
		* Langwell devices reside at fixed offsets, don't try to move them.

arch/x86/platform/intel-mid/Makefile

+1 −1

Original line number	Diff line number	Diff line
		obj-$(CONFIG_X86_INTEL_MID) += intel-mid.o intel_mid_vrtc.o mfld.o mrfl.o
		obj-$(CONFIG_X86_INTEL_MID) += intel-mid.o intel_mid_vrtc.o mfld.o mrfl.o pwr.o

		# SFI specific code
		ifdef CONFIG_X86_INTEL_MID

arch/x86/platform/intel-mid/pwr.c

0 → 100644

+416 −0

Original line number	Diff line number	Diff line
		/*
		* Intel MID Power Management Unit (PWRMU) device driver
		*
		* Copyright (C) 2016, Intel Corporation
		*
		* Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
		*
		* This program is free software; you can redistribute it and/or modify it
		* under the terms and conditions of the GNU General Public License,
		* version 2, as published by the Free Software Foundation.
		*
		* Intel MID Power Management Unit device driver handles the South Complex PCI
		* devices such as GPDMA, SPI, I2C, PWM, and so on. By default PCI core
		* modifies bits in PMCSR register in the PCI configuration space. This is not
		* enough on some SoCs like Intel Tangier. In such case PCI core sets a new
		* power state of the device in question through a PM hook registered in struct
		* pci_platform_pm_ops (see drivers/pci/pci-mid.c).
		*/

		#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

		#include <linux/delay.h>
		#include <linux/errno.h>
		#include <linux/init.h>
		#include <linux/interrupt.h>
		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/mutex.h>
		#include <linux/pci.h>

		#include <asm/intel-mid.h>

		/* Registers */
		#define PM_STS 0x00
		#define PM_CMD 0x04
		#define PM_ICS 0x08
		#define PM_WKC(x) (0x10 + (x) * 4)
		#define PM_WKS(x) (0x18 + (x) * 4)
		#define PM_SSC(x) (0x20 + (x) * 4)
		#define PM_SSS(x) (0x30 + (x) * 4)

		/* Bits in PM_STS */
		#define PM_STS_BUSY (1 << 8)

		/* Bits in PM_CMD */
		#define PM_CMD_CMD(x) ((x) << 0)
		#define PM_CMD_IOC (1 << 8)
		#define PM_CMD_D3cold (1 << 21)

		/* List of commands */
		#define CMD_SET_CFG 0x01

		/* Bits in PM_ICS */
		#define PM_ICS_INT_STATUS(x) ((x) & 0xff)
		#define PM_ICS_IE (1 << 8)
		#define PM_ICS_IP (1 << 9)
		#define PM_ICS_SW_INT_STS (1 << 10)

		/* List of interrupts */
		#define INT_INVALID 0
		#define INT_CMD_COMPLETE 1
		#define INT_CMD_ERR 2
		#define INT_WAKE_EVENT 3
		#define INT_LSS_POWER_ERR 4
		#define INT_S0iX_MSG_ERR 5
		#define INT_NO_C6 6
		#define INT_TRIGGER_ERR 7
		#define INT_INACTIVITY 8

		/* South Complex devices */
		#define LSS_MAX_SHARED_DEVS 4
		#define LSS_MAX_DEVS 64

		#define LSS_WS_BITS 1 /* wake state width */
		#define LSS_PWS_BITS 2 /* power state width */

		/* Supported device IDs */
		#define PCI_DEVICE_ID_TANGIER 0x11a1

		struct mid_pwr_dev {
		struct pci_dev *pdev;
		pci_power_t state;
		};

		struct mid_pwr {
		struct device *dev;
		void __iomem *regs;
		int irq;
		bool available;

		struct mutex lock;
		struct mid_pwr_dev lss[LSS_MAX_DEVS][LSS_MAX_SHARED_DEVS];
		};

		static struct mid_pwr *midpwr;

		static u32 mid_pwr_get_state(struct mid_pwr *pwr, int reg)
		{
		return readl(pwr->regs + PM_SSS(reg));
		}

		static void mid_pwr_set_state(struct mid_pwr *pwr, int reg, u32 value)
		{
		writel(value, pwr->regs + PM_SSC(reg));
		}

		static void mid_pwr_set_wake(struct mid_pwr *pwr, int reg, u32 value)
		{
		writel(value, pwr->regs + PM_WKC(reg));
		}

		static void mid_pwr_interrupt_disable(struct mid_pwr *pwr)
		{
		writel(~PM_ICS_IE, pwr->regs + PM_ICS);
		}

		static bool mid_pwr_is_busy(struct mid_pwr *pwr)
		{
		return !!(readl(pwr->regs + PM_STS) & PM_STS_BUSY);
		}

		/* Wait 500ms that the latest PWRMU command finished */
		static int mid_pwr_wait(struct mid_pwr *pwr)
		{
		unsigned int count = 500000;
		bool busy;

		do {
		busy = mid_pwr_is_busy(pwr);
		if (!busy)
		return 0;
		udelay(1);
		} while (--count);

		return -EBUSY;
		}

		static int mid_pwr_wait_for_cmd(struct mid_pwr *pwr, u8 cmd)
		{
		writel(PM_CMD_CMD(cmd), pwr->regs + PM_CMD);
		return mid_pwr_wait(pwr);
		}

		static int __update_power_state(struct mid_pwr *pwr, int reg, int bit, int new)
		{
		int curstate;
		u32 power;
		int ret;

		/* Check if the device is already in desired state */
		power = mid_pwr_get_state(pwr, reg);
		curstate = (power >> bit) & 3;
		if (curstate == new)
		return 0;

		/* Update the power state */
		mid_pwr_set_state(pwr, reg, (power & ~(3 << bit)) \| (new << bit));

		/* Send command to SCU */
		ret = mid_pwr_wait_for_cmd(pwr, CMD_SET_CFG);
		if (ret)
		return ret;

		/* Check if the device is already in desired state */
		power = mid_pwr_get_state(pwr, reg);
		curstate = (power >> bit) & 3;
		if (curstate != new)
		return -EAGAIN;

		return 0;
		}

		static pci_power_t __find_weakest_power_state(struct mid_pwr_dev *lss,
		struct pci_dev *pdev,
		pci_power_t state)
		{
		pci_power_t weakest = PCI_D3hot;
		unsigned int j;

		/* Find device in cache or first free cell */
		for (j = 0; j < LSS_MAX_SHARED_DEVS; j++) {
		if (lss[j].pdev == pdev \|\| !lss[j].pdev)
		break;
		}

		/* Store the desired state in cache */
		if (j < LSS_MAX_SHARED_DEVS) {
		lss[j].pdev = pdev;
		lss[j].state = state;
		} else {
		dev_WARN(&pdev->dev, "No room for device in PWRMU LSS cache\n");
		weakest = state;
		}

		/* Find the power state we may use */
		for (j = 0; j < LSS_MAX_SHARED_DEVS; j++) {
		if (lss[j].state < weakest)
		weakest = lss[j].state;
		}

		return weakest;
		}

		static int __set_power_state(struct mid_pwr pwr, struct pci_dev pdev,
		pci_power_t state, int id, int reg, int bit)
		{
		const char *name;
		int ret;

		state = __find_weakest_power_state(pwr->lss[id], pdev, state);
		name = pci_power_name(state);

		ret = __update_power_state(pwr, reg, bit, (__force int)state);
		if (ret) {
		dev_warn(&pdev->dev, "Can't set power state %s: %d\n", name, ret);
		return ret;
		}

		dev_vdbg(&pdev->dev, "Set power state %s\n", name);
		return 0;
		}

		static int mid_pwr_set_power_state(struct mid_pwr pwr, struct pci_dev pdev,
		pci_power_t state)
		{
		int id, reg, bit;
		int ret;

		id = intel_mid_pwr_get_lss_id(pdev);
		if (id < 0)
		return id;

		reg = (id * LSS_PWS_BITS) / 32;
		bit = (id * LSS_PWS_BITS) % 32;

		/* We support states between PCI_D0 and PCI_D3hot */
		if (state < PCI_D0)
		state = PCI_D0;
		if (state > PCI_D3hot)
		state = PCI_D3hot;

		mutex_lock(&pwr->lock);
		ret = __set_power_state(pwr, pdev, state, id, reg, bit);
		mutex_unlock(&pwr->lock);
		return ret;
		}

		int intel_mid_pci_set_power_state(struct pci_dev *pdev, pci_power_t state)
		{
		struct mid_pwr *pwr = midpwr;
		int ret = 0;

		might_sleep();

		if (pwr && pwr->available)
		ret = mid_pwr_set_power_state(pwr, pdev, state);
		dev_vdbg(&pdev->dev, "set_power_state() returns %d\n", ret);

		return 0;
		}
		EXPORT_SYMBOL_GPL(intel_mid_pci_set_power_state);

		int intel_mid_pwr_get_lss_id(struct pci_dev *pdev)
		{
		int vndr;
		u8 id;

		/*
		* Mapping to PWRMU index is kept in the Logical SubSystem ID byte of
		* Vendor capability.
		*/
		vndr = pci_find_capability(pdev, PCI_CAP_ID_VNDR);
		if (!vndr)
		return -EINVAL;

		/* Read the Logical SubSystem ID byte */
		pci_read_config_byte(pdev, vndr + INTEL_MID_PWR_LSS_OFFSET, &id);
		if (!(id & INTEL_MID_PWR_LSS_TYPE))
		return -ENODEV;

		id &= ~INTEL_MID_PWR_LSS_TYPE;
		if (id >= LSS_MAX_DEVS)
		return -ERANGE;

		return id;
		}

		static irqreturn_t mid_pwr_irq_handler(int irq, void *dev_id)
		{
		struct mid_pwr *pwr = dev_id;
		u32 ics;

		ics = readl(pwr->regs + PM_ICS);
		if (!(ics & PM_ICS_IP))
		return IRQ_NONE;

		writel(ics \| PM_ICS_IP, pwr->regs + PM_ICS);

		dev_warn(pwr->dev, "Unexpected IRQ: %#x\n", PM_ICS_INT_STATUS(ics));
		return IRQ_HANDLED;
		}

		struct mid_pwr_device_info {
		int (set_initial_state)(struct mid_pwr pwr);
		};

		static int mid_pwr_probe(struct pci_dev pdev, const struct pci_device_id id)
		{
		struct mid_pwr_device_info info = (void )id->driver_data;
		struct device *dev = &pdev->dev;
		struct mid_pwr *pwr;
		int ret;

		ret = pcim_enable_device(pdev);
		if (ret < 0) {
		dev_err(&pdev->dev, "error: could not enable device\n");
		return ret;
		}

		ret = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
		if (ret) {
		dev_err(&pdev->dev, "I/O memory remapping failed\n");
		return ret;
		}

		pwr = devm_kzalloc(dev, sizeof(*pwr), GFP_KERNEL);
		if (!pwr)
		return -ENOMEM;

		pwr->dev = dev;
		pwr->regs = pcim_iomap_table(pdev)[0];
		pwr->irq = pdev->irq;

		mutex_init(&pwr->lock);

		/* Disable interrupts */
		mid_pwr_interrupt_disable(pwr);

		if (info && info->set_initial_state) {
		ret = info->set_initial_state(pwr);
		if (ret)
		dev_warn(dev, "Can't set initial state: %d\n", ret);
		}

		ret = devm_request_irq(dev, pdev->irq, mid_pwr_irq_handler,
		IRQF_NO_SUSPEND, pci_name(pdev), pwr);
		if (ret)
		return ret;

		pwr->available = true;
		midpwr = pwr;

		pci_set_drvdata(pdev, pwr);
		return 0;
		}

		static int tng_set_initial_state(struct mid_pwr *pwr)
		{
		unsigned int i, j;
		int ret;

		/*
		* Enable wake events.
		*
		* PWRMU supports up to 32 sources for wake up the system. Ungate them
		* all here.
		*/
		mid_pwr_set_wake(pwr, 0, 0xffffffff);
		mid_pwr_set_wake(pwr, 1, 0xffffffff);

		/*
		* Power off South Complex devices.
		*
		* There is a map (see a note below) of 64 devices with 2 bits per each
		* on 32-bit HW registers. The following calls set all devices to one
		* known initial state, i.e. PCI_D3hot. This is done in conjunction
		* with PMCSR setting in arch/x86/pci/intel_mid_pci.c.
		*
		* NOTE: The actual device mapping is provided by a platform at run
		* time using vendor capability of PCI configuration space.
		*/
		mid_pwr_set_state(pwr, 0, 0xffffffff);
		mid_pwr_set_state(pwr, 1, 0xffffffff);
		mid_pwr_set_state(pwr, 2, 0xffffffff);
		mid_pwr_set_state(pwr, 3, 0xffffffff);

		/* Send command to SCU */
		ret = mid_pwr_wait_for_cmd(pwr, CMD_SET_CFG);
		if (ret)
		return ret;

		for (i = 0; i < LSS_MAX_DEVS; i++) {
		for (j = 0; j < LSS_MAX_SHARED_DEVS; j++)
		pwr->lss[i][j].state = PCI_D3hot;
		}

		return 0;
		}

		static const struct mid_pwr_device_info tng_info = {
		.set_initial_state = tng_set_initial_state,
		};

		static const struct pci_device_id mid_pwr_pci_ids[] = {
		{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_TANGIER), (kernel_ulong_t)&tng_info },
		{}
		};
		MODULE_DEVICE_TABLE(pci, mid_pwr_pci_ids);

		static struct pci_driver mid_pwr_pci_driver = {
		.name = "intel_mid_pwr",
		.probe = mid_pwr_probe,
		.id_table = mid_pwr_pci_ids,
		};

		builtin_pci_driver(mid_pwr_pci_driver);

drivers/pci/Makefile

+3 −0

Original line number	Diff line number	Diff line
		@@ -51,6 +51,9 @@ obj-$(CONFIG_ACPI) += pci-acpi.o
		# SMBIOS provided firmware instance and labels
		obj-$(CONFIG_PCI_LABEL) += pci-label.o

		# Intel MID platform PM support
		obj-$(CONFIG_X86_INTEL_MID) += pci-mid.o

		obj-$(CONFIG_PCI_SYSCALL) += syscall.o

		obj-$(CONFIG_PCI_STUB) += pci-stub.o

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