drivers/cpuidle/cpuidle-qcom-spm.c - linux/torvalds/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (c) 2011-2014, The Linux Foundation. All rights reserved.
  * Copyright (c) 2014,2015, Linaro Ltd.
  *
  * SAW power controller driver
  */

 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
 #include <linux/err.h>
 #include <linux/platform_device.h>
 #include <linux/cpuidle.h>
 #include <linux/cpu_pm.h>
 #include <linux/qcom_scm.h>

 #include <asm/proc-fns.h>
 #include <asm/suspend.h>

 #include "dt_idle_states.h"

 #define MAX_PMIC_DATA		2
 #define MAX_SEQ_DATA		64
 #define SPM_CTL_INDEX		0x7f
 #define SPM_CTL_INDEX_SHIFT	4
 #define SPM_CTL_EN		BIT(0)

 enum pm_sleep_mode {
 	PM_SLEEP_MODE_STBY,
 	PM_SLEEP_MODE_RET,
 	PM_SLEEP_MODE_SPC,
 	PM_SLEEP_MODE_PC,
 	PM_SLEEP_MODE_NR,
 };

 enum spm_reg {
 	SPM_REG_CFG,
 	SPM_REG_SPM_CTL,
 	SPM_REG_DLY,
 	SPM_REG_PMIC_DLY,
 	SPM_REG_PMIC_DATA_0,
 	SPM_REG_PMIC_DATA_1,
 	SPM_REG_VCTL,
 	SPM_REG_SEQ_ENTRY,
 	SPM_REG_SPM_STS,
 	SPM_REG_PMIC_STS,
 	SPM_REG_NR,
 };

 struct spm_reg_data {
 	const u8 *reg_offset;
 	u32 spm_cfg;
 	u32 spm_dly;
 	u32 pmic_dly;
 	u32 pmic_data[MAX_PMIC_DATA];
 	u8 seq[MAX_SEQ_DATA];
 	u8 start_index[PM_SLEEP_MODE_NR];
 };

 struct spm_driver_data {
 	struct cpuidle_driver cpuidle_driver;
 	void __iomem *reg_base;
 	const struct spm_reg_data *reg_data;
 };

 static const u8 spm_reg_offset_v2_1[SPM_REG_NR] = {
 	[SPM_REG_CFG]		= 0x08,
 	[SPM_REG_SPM_CTL]	= 0x30,
 	[SPM_REG_DLY]		= 0x34,
 	[SPM_REG_SEQ_ENTRY]	= 0x80,
 };

 /* SPM register data for 8974, 8084 */
 static const struct spm_reg_data spm_reg_8974_8084_cpu  = {
 	.reg_offset = spm_reg_offset_v2_1,
 	.spm_cfg = 0x1,
 	.spm_dly = 0x3C102800,
 	.seq = { 0x03, 0x0B, 0x0F, 0x00, 0x20, 0x80, 0x10, 0xE8, 0x5B, 0x03,
 		0x3B, 0xE8, 0x5B, 0x82, 0x10, 0x0B, 0x30, 0x06, 0x26, 0x30,
 		0x0F },
 	.start_index[PM_SLEEP_MODE_STBY] = 0,
 	.start_index[PM_SLEEP_MODE_SPC] = 3,
 };

 /* SPM register data for 8226 */
 static const struct spm_reg_data spm_reg_8226_cpu  = {
 	.reg_offset = spm_reg_offset_v2_1,
 	.spm_cfg = 0x0,
 	.spm_dly = 0x3C102800,
 	.seq = { 0x60, 0x03, 0x60, 0x0B, 0x0F, 0x20, 0x10, 0x80, 0x30, 0x90,
 		0x5B, 0x60, 0x03, 0x60, 0x3B, 0x76, 0x76, 0x0B, 0x94, 0x5B,
 		0x80, 0x10, 0x26, 0x30, 0x0F },
 	.start_index[PM_SLEEP_MODE_STBY] = 0,
 	.start_index[PM_SLEEP_MODE_SPC] = 5,
 };

 static const u8 spm_reg_offset_v1_1[SPM_REG_NR] = {
 	[SPM_REG_CFG]		= 0x08,
 	[SPM_REG_SPM_CTL]	= 0x20,
 	[SPM_REG_PMIC_DLY]	= 0x24,
 	[SPM_REG_PMIC_DATA_0]	= 0x28,
 	[SPM_REG_PMIC_DATA_1]	= 0x2C,
 	[SPM_REG_SEQ_ENTRY]	= 0x80,
 };

 /* SPM register data for 8064 */
 static const struct spm_reg_data spm_reg_8064_cpu = {
 	.reg_offset = spm_reg_offset_v1_1,
 	.spm_cfg = 0x1F,
 	.pmic_dly = 0x02020004,
 	.pmic_data[0] = 0x0084009C,
 	.pmic_data[1] = 0x00A4001C,
 	.seq = { 0x03, 0x0F, 0x00, 0x24, 0x54, 0x10, 0x09, 0x03, 0x01,
 		0x10, 0x54, 0x30, 0x0C, 0x24, 0x30, 0x0F },
 	.start_index[PM_SLEEP_MODE_STBY] = 0,
 	.start_index[PM_SLEEP_MODE_SPC] = 2,
 };

 static inline void spm_register_write(struct spm_driver_data *drv,
 					enum spm_reg reg, u32 val)
 {
 	if (drv->reg_data->reg_offset[reg])
 		writel_relaxed(val, drv->reg_base +
 				drv->reg_data->reg_offset[reg]);
 }

 /* Ensure a guaranteed write, before return */
 static inline void spm_register_write_sync(struct spm_driver_data *drv,
 					enum spm_reg reg, u32 val)
 {
 	u32 ret;

 	if (!drv->reg_data->reg_offset[reg])
 		return;

 	do {
 		writel_relaxed(val, drv->reg_base +
 				drv->reg_data->reg_offset[reg]);
 		ret = readl_relaxed(drv->reg_base +
 				drv->reg_data->reg_offset[reg]);
 		if (ret == val)
 			break;
 		cpu_relax();
 	} while (1);
 }

 static inline u32 spm_register_read(struct spm_driver_data *drv,
 					enum spm_reg reg)
 {
 	return readl_relaxed(drv->reg_base + drv->reg_data->reg_offset[reg]);
 }

 static void spm_set_low_power_mode(struct spm_driver_data *drv,
 					enum pm_sleep_mode mode)
 {
 	u32 start_index;
 	u32 ctl_val;

 	start_index = drv->reg_data->start_index[mode];

 	ctl_val = spm_register_read(drv, SPM_REG_SPM_CTL);
 	ctl_val &= ~(SPM_CTL_INDEX << SPM_CTL_INDEX_SHIFT);
 	ctl_val |= start_index << SPM_CTL_INDEX_SHIFT;
 	ctl_val |= SPM_CTL_EN;
 	spm_register_write_sync(drv, SPM_REG_SPM_CTL, ctl_val);
 }

 static int qcom_pm_collapse(unsigned long int unused)
 {
 	qcom_scm_cpu_power_down(QCOM_SCM_CPU_PWR_DOWN_L2_ON);

 	/*
 	 * Returns here only if there was a pending interrupt and we did not
 	 * power down as a result.
 	 */
 	return -1;
 }

 static int qcom_cpu_spc(struct spm_driver_data *drv)
 {
 	int ret;

 	spm_set_low_power_mode(drv, PM_SLEEP_MODE_SPC);
 	ret = cpu_suspend(0, qcom_pm_collapse);
 	/*
 	 * ARM common code executes WFI without calling into our driver and
 	 * if the SPM mode is not reset, then we may accidently power down the
 	 * cpu when we intended only to gate the cpu clock.
 	 * Ensure the state is set to standby before returning.
 	 */
 	spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);

 	return ret;
 }

 static int spm_enter_idle_state(struct cpuidle_device *dev,
 				struct cpuidle_driver *drv, int idx)
 {
 	struct spm_driver_data *data = container_of(drv, struct spm_driver_data,
 						    cpuidle_driver);

 	return CPU_PM_CPU_IDLE_ENTER_PARAM(qcom_cpu_spc, idx, data);
 }

 static struct cpuidle_driver qcom_spm_idle_driver = {
 	.name = "qcom_spm",
 	.owner = THIS_MODULE,
 	.states[0] = {
 		.enter			= spm_enter_idle_state,
 		.exit_latency		= 1,
 		.target_residency	= 1,
 		.power_usage		= UINT_MAX,
 		.name			= "WFI",
 		.desc			= "ARM WFI",
 	}
 };

 static const struct of_device_id qcom_idle_state_match[] = {
 	{ .compatible = "qcom,idle-state-spc", .data = spm_enter_idle_state },
 	{ },
 };

 static int spm_cpuidle_init(struct cpuidle_driver *drv, int cpu)
 {
 	int ret;

 	memcpy(drv, &qcom_spm_idle_driver, sizeof(*drv));
 	drv->cpumask = (struct cpumask *)cpumask_of(cpu);

 	/* Parse idle states from device tree */
 	ret = dt_init_idle_driver(drv, qcom_idle_state_match, 1);
 	if (ret <= 0)
 		return ret ? : -ENODEV;

 	/* We have atleast one power down mode */
 	return qcom_scm_set_warm_boot_addr(cpu_resume_arm, drv->cpumask);
 }

 static struct spm_driver_data *spm_get_drv(struct platform_device *pdev,
 		int *spm_cpu)
 {
 	struct spm_driver_data *drv = NULL;
 	struct device_node *cpu_node, *saw_node;
 	int cpu;
 	bool found = 0;

 	for_each_possible_cpu(cpu) {
 		cpu_node = of_cpu_device_node_get(cpu);
 		if (!cpu_node)
 			continue;
 		saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0);
 		found = (saw_node == pdev->dev.of_node);
 		of_node_put(saw_node);
 		of_node_put(cpu_node);
 		if (found)
 			break;
 	}

 	if (found) {
 		drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_KERNEL);
 		if (drv)
 			*spm_cpu = cpu;
 	}

 	return drv;
 }

 static const struct of_device_id spm_match_table[] = {
 	{ .compatible = "qcom,msm8226-saw2-v2.1-cpu",
 	  .data = &spm_reg_8226_cpu },
 	{ .compatible = "qcom,msm8974-saw2-v2.1-cpu",
 	  .data = &spm_reg_8974_8084_cpu },
 	{ .compatible = "qcom,apq8084-saw2-v2.1-cpu",
 	  .data = &spm_reg_8974_8084_cpu },
 	{ .compatible = "qcom,apq8064-saw2-v1.1-cpu",
 	  .data = &spm_reg_8064_cpu },
 	{ },
 };

 static int spm_dev_probe(struct platform_device *pdev)
 {
 	struct spm_driver_data *drv;
 	struct resource *res;
 	const struct of_device_id *match_id;
 	void __iomem *addr;
 	int cpu, ret;

 	if (!qcom_scm_is_available())
 		return -EPROBE_DEFER;

 	drv = spm_get_drv(pdev, &cpu);
 	if (!drv)
 		return -EINVAL;
 	platform_set_drvdata(pdev, drv);

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	drv->reg_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(drv->reg_base))
 		return PTR_ERR(drv->reg_base);

 	match_id = of_match_node(spm_match_table, pdev->dev.of_node);
 	if (!match_id)
 		return -ENODEV;

 	drv->reg_data = match_id->data;

 	ret = spm_cpuidle_init(&drv->cpuidle_driver, cpu);
 	if (ret)
 		return ret;

 	/* Write the SPM sequences first.. */
 	addr = drv->reg_base + drv->reg_data->reg_offset[SPM_REG_SEQ_ENTRY];
 	__iowrite32_copy(addr, drv->reg_data->seq,
 			ARRAY_SIZE(drv->reg_data->seq) / 4);

 	/*
 	 * ..and then the control registers.
 	 * On some SoC if the control registers are written first and if the
 	 * CPU was held in reset, the reset signal could trigger the SPM state
 	 * machine, before the sequences are completely written.
 	 */
 	spm_register_write(drv, SPM_REG_CFG, drv->reg_data->spm_cfg);
 	spm_register_write(drv, SPM_REG_DLY, drv->reg_data->spm_dly);
 	spm_register_write(drv, SPM_REG_PMIC_DLY, drv->reg_data->pmic_dly);
 	spm_register_write(drv, SPM_REG_PMIC_DATA_0,
 				drv->reg_data->pmic_data[0]);
 	spm_register_write(drv, SPM_REG_PMIC_DATA_1,
 				drv->reg_data->pmic_data[1]);

 	/* Set up Standby as the default low power mode */
 	spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);

 	return cpuidle_register(&drv->cpuidle_driver, NULL);
 }

 static int spm_dev_remove(struct platform_device *pdev)
 {
 	struct spm_driver_data *drv = platform_get_drvdata(pdev);

 	cpuidle_unregister(&drv->cpuidle_driver);
 	return 0;
 }

 static struct platform_driver spm_driver = {
 	.probe = spm_dev_probe,
 	.remove = spm_dev_remove,
 	.driver = {
 		.name = "saw",
 		.of_match_table = spm_match_table,
 	},
 };

 builtin_platform_driver(spm_driver);
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright (c) 2011-2014, The Linux Foundation. All rights reserved.
	* Copyright (c) 2014,2015, Linaro Ltd.
	*
	* SAW power controller driver
	*/

	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/io.h>
	#include <linux/slab.h>
	#include <linux/of.h>
	#include <linux/of_address.h>
	#include <linux/of_device.h>
	#include <linux/err.h>
	#include <linux/platform_device.h>
	#include <linux/cpuidle.h>
	#include <linux/cpu_pm.h>
	#include <linux/qcom_scm.h>

	#include <asm/proc-fns.h>
	#include <asm/suspend.h>

	#include "dt_idle_states.h"

	#define MAX_PMIC_DATA 2
	#define MAX_SEQ_DATA 64
	#define SPM_CTL_INDEX 0x7f
	#define SPM_CTL_INDEX_SHIFT 4
	#define SPM_CTL_EN BIT(0)

	enum pm_sleep_mode {
	PM_SLEEP_MODE_STBY,
	PM_SLEEP_MODE_RET,
	PM_SLEEP_MODE_SPC,
	PM_SLEEP_MODE_PC,
	PM_SLEEP_MODE_NR,
	};

	enum spm_reg {
	SPM_REG_CFG,
	SPM_REG_SPM_CTL,
	SPM_REG_DLY,
	SPM_REG_PMIC_DLY,
	SPM_REG_PMIC_DATA_0,
	SPM_REG_PMIC_DATA_1,
	SPM_REG_VCTL,
	SPM_REG_SEQ_ENTRY,
	SPM_REG_SPM_STS,
	SPM_REG_PMIC_STS,
	SPM_REG_NR,
	};

	struct spm_reg_data {
	const u8 *reg_offset;
	u32 spm_cfg;
	u32 spm_dly;
	u32 pmic_dly;
	u32 pmic_data[MAX_PMIC_DATA];
	u8 seq[MAX_SEQ_DATA];
	u8 start_index[PM_SLEEP_MODE_NR];
	};

	struct spm_driver_data {
	struct cpuidle_driver cpuidle_driver;
	void __iomem *reg_base;
	const struct spm_reg_data *reg_data;
	};

	static const u8 spm_reg_offset_v2_1[SPM_REG_NR] = {
	[SPM_REG_CFG] = 0x08,
	[SPM_REG_SPM_CTL] = 0x30,
	[SPM_REG_DLY] = 0x34,
	[SPM_REG_SEQ_ENTRY] = 0x80,
	};

	/* SPM register data for 8974, 8084 */
	static const struct spm_reg_data spm_reg_8974_8084_cpu = {
	.reg_offset = spm_reg_offset_v2_1,
	.spm_cfg = 0x1,
	.spm_dly = 0x3C102800,
	.seq = { 0x03, 0x0B, 0x0F, 0x00, 0x20, 0x80, 0x10, 0xE8, 0x5B, 0x03,
	0x3B, 0xE8, 0x5B, 0x82, 0x10, 0x0B, 0x30, 0x06, 0x26, 0x30,
	0x0F },
	.start_index[PM_SLEEP_MODE_STBY] = 0,
	.start_index[PM_SLEEP_MODE_SPC] = 3,
	};

	/* SPM register data for 8226 */
	static const struct spm_reg_data spm_reg_8226_cpu = {
	.reg_offset = spm_reg_offset_v2_1,
	.spm_cfg = 0x0,
	.spm_dly = 0x3C102800,
	.seq = { 0x60, 0x03, 0x60, 0x0B, 0x0F, 0x20, 0x10, 0x80, 0x30, 0x90,
	0x5B, 0x60, 0x03, 0x60, 0x3B, 0x76, 0x76, 0x0B, 0x94, 0x5B,
	0x80, 0x10, 0x26, 0x30, 0x0F },
	.start_index[PM_SLEEP_MODE_STBY] = 0,
	.start_index[PM_SLEEP_MODE_SPC] = 5,
	};

	static const u8 spm_reg_offset_v1_1[SPM_REG_NR] = {
	[SPM_REG_CFG] = 0x08,
	[SPM_REG_SPM_CTL] = 0x20,
	[SPM_REG_PMIC_DLY] = 0x24,
	[SPM_REG_PMIC_DATA_0] = 0x28,
	[SPM_REG_PMIC_DATA_1] = 0x2C,
	[SPM_REG_SEQ_ENTRY] = 0x80,
	};

	/* SPM register data for 8064 */
	static const struct spm_reg_data spm_reg_8064_cpu = {
	.reg_offset = spm_reg_offset_v1_1,
	.spm_cfg = 0x1F,
	.pmic_dly = 0x02020004,
	.pmic_data[0] = 0x0084009C,
	.pmic_data[1] = 0x00A4001C,
	.seq = { 0x03, 0x0F, 0x00, 0x24, 0x54, 0x10, 0x09, 0x03, 0x01,
	0x10, 0x54, 0x30, 0x0C, 0x24, 0x30, 0x0F },
	.start_index[PM_SLEEP_MODE_STBY] = 0,
	.start_index[PM_SLEEP_MODE_SPC] = 2,
	};

	static inline void spm_register_write(struct spm_driver_data *drv,
	enum spm_reg reg, u32 val)
	{
	if (drv->reg_data->reg_offset[reg])
	writel_relaxed(val, drv->reg_base +
	drv->reg_data->reg_offset[reg]);
	}

	/* Ensure a guaranteed write, before return */
	static inline void spm_register_write_sync(struct spm_driver_data *drv,
	enum spm_reg reg, u32 val)
	{
	u32 ret;

	if (!drv->reg_data->reg_offset[reg])
	return;

	do {
	writel_relaxed(val, drv->reg_base +
	drv->reg_data->reg_offset[reg]);
	ret = readl_relaxed(drv->reg_base +
	drv->reg_data->reg_offset[reg]);
	if (ret == val)
	break;
	cpu_relax();
	} while (1);
	}

	static inline u32 spm_register_read(struct spm_driver_data *drv,
	enum spm_reg reg)
	{
	return readl_relaxed(drv->reg_base + drv->reg_data->reg_offset[reg]);
	}

	static void spm_set_low_power_mode(struct spm_driver_data *drv,
	enum pm_sleep_mode mode)
	{
	u32 start_index;
	u32 ctl_val;

	start_index = drv->reg_data->start_index[mode];

	ctl_val = spm_register_read(drv, SPM_REG_SPM_CTL);
	ctl_val &= ~(SPM_CTL_INDEX << SPM_CTL_INDEX_SHIFT);
	ctl_val \|= start_index << SPM_CTL_INDEX_SHIFT;
	ctl_val \|= SPM_CTL_EN;
	spm_register_write_sync(drv, SPM_REG_SPM_CTL, ctl_val);
	}

	static int qcom_pm_collapse(unsigned long int unused)
	{
	qcom_scm_cpu_power_down(QCOM_SCM_CPU_PWR_DOWN_L2_ON);

	/*
	* Returns here only if there was a pending interrupt and we did not
	* power down as a result.
	*/
	return -1;
	}

	static int qcom_cpu_spc(struct spm_driver_data *drv)
	{
	int ret;

	spm_set_low_power_mode(drv, PM_SLEEP_MODE_SPC);
	ret = cpu_suspend(0, qcom_pm_collapse);
	/*
	* ARM common code executes WFI without calling into our driver and
	* if the SPM mode is not reset, then we may accidently power down the
	* cpu when we intended only to gate the cpu clock.
	* Ensure the state is set to standby before returning.
	*/
	spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);

	return ret;
	}

	static int spm_enter_idle_state(struct cpuidle_device *dev,
	struct cpuidle_driver *drv, int idx)
	{
	struct spm_driver_data *data = container_of(drv, struct spm_driver_data,
	cpuidle_driver);

	return CPU_PM_CPU_IDLE_ENTER_PARAM(qcom_cpu_spc, idx, data);
	}

	static struct cpuidle_driver qcom_spm_idle_driver = {
	.name = "qcom_spm",
	.owner = THIS_MODULE,
	.states[0] = {
	.enter = spm_enter_idle_state,
	.exit_latency = 1,
	.target_residency = 1,
	.power_usage = UINT_MAX,
	.name = "WFI",
	.desc = "ARM WFI",
	}
	};

	static const struct of_device_id qcom_idle_state_match[] = {
	{ .compatible = "qcom,idle-state-spc", .data = spm_enter_idle_state },
	{ },
	};

	static int spm_cpuidle_init(struct cpuidle_driver *drv, int cpu)
	{
	int ret;

	memcpy(drv, &qcom_spm_idle_driver, sizeof(*drv));
	drv->cpumask = (struct cpumask *)cpumask_of(cpu);

	/* Parse idle states from device tree */
	ret = dt_init_idle_driver(drv, qcom_idle_state_match, 1);
	if (ret <= 0)
	return ret ? : -ENODEV;

	/* We have atleast one power down mode */
	return qcom_scm_set_warm_boot_addr(cpu_resume_arm, drv->cpumask);
	}

	static struct spm_driver_data spm_get_drv(struct platform_device pdev,
	int *spm_cpu)
	{
	struct spm_driver_data *drv = NULL;
	struct device_node cpu_node, saw_node;
	int cpu;
	bool found = 0;

	for_each_possible_cpu(cpu) {
	cpu_node = of_cpu_device_node_get(cpu);
	if (!cpu_node)
	continue;
	saw_node = of_parse_phandle(cpu_node, "qcom,saw", 0);
	found = (saw_node == pdev->dev.of_node);
	of_node_put(saw_node);
	of_node_put(cpu_node);
	if (found)
	break;
	}

	if (found) {
	drv = devm_kzalloc(&pdev->dev, sizeof(*drv), GFP_KERNEL);
	if (drv)
	*spm_cpu = cpu;
	}

	return drv;
	}

	static const struct of_device_id spm_match_table[] = {
	{ .compatible = "qcom,msm8226-saw2-v2.1-cpu",
	.data = &spm_reg_8226_cpu },
	{ .compatible = "qcom,msm8974-saw2-v2.1-cpu",
	.data = &spm_reg_8974_8084_cpu },
	{ .compatible = "qcom,apq8084-saw2-v2.1-cpu",
	.data = &spm_reg_8974_8084_cpu },
	{ .compatible = "qcom,apq8064-saw2-v1.1-cpu",
	.data = &spm_reg_8064_cpu },
	{ },
	};

	static int spm_dev_probe(struct platform_device *pdev)
	{
	struct spm_driver_data *drv;
	struct resource *res;
	const struct of_device_id *match_id;
	void __iomem *addr;
	int cpu, ret;

	if (!qcom_scm_is_available())
	return -EPROBE_DEFER;

	drv = spm_get_drv(pdev, &cpu);
	if (!drv)
	return -EINVAL;
	platform_set_drvdata(pdev, drv);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	drv->reg_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(drv->reg_base))
	return PTR_ERR(drv->reg_base);

	match_id = of_match_node(spm_match_table, pdev->dev.of_node);
	if (!match_id)
	return -ENODEV;

	drv->reg_data = match_id->data;

	ret = spm_cpuidle_init(&drv->cpuidle_driver, cpu);
	if (ret)
	return ret;

	/* Write the SPM sequences first.. */
	addr = drv->reg_base + drv->reg_data->reg_offset[SPM_REG_SEQ_ENTRY];
	__iowrite32_copy(addr, drv->reg_data->seq,
	ARRAY_SIZE(drv->reg_data->seq) / 4);

	/*
	* ..and then the control registers.
	* On some SoC if the control registers are written first and if the
	* CPU was held in reset, the reset signal could trigger the SPM state
	* machine, before the sequences are completely written.
	*/
	spm_register_write(drv, SPM_REG_CFG, drv->reg_data->spm_cfg);
	spm_register_write(drv, SPM_REG_DLY, drv->reg_data->spm_dly);
	spm_register_write(drv, SPM_REG_PMIC_DLY, drv->reg_data->pmic_dly);
	spm_register_write(drv, SPM_REG_PMIC_DATA_0,
	drv->reg_data->pmic_data[0]);
	spm_register_write(drv, SPM_REG_PMIC_DATA_1,
	drv->reg_data->pmic_data[1]);

	/* Set up Standby as the default low power mode */
	spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);

	return cpuidle_register(&drv->cpuidle_driver, NULL);
	}

	static int spm_dev_remove(struct platform_device *pdev)
	{
	struct spm_driver_data *drv = platform_get_drvdata(pdev);

	cpuidle_unregister(&drv->cpuidle_driver);
	return 0;
	}

	static struct platform_driver spm_driver = {
	.probe = spm_dev_probe,
	.remove = spm_dev_remove,
	.driver = {
	.name = "saw",
	.of_match_table = spm_match_table,
	},
	};

	builtin_platform_driver(spm_driver);