1 files changed, 344 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle-qcom-spm.c b/drivers/cpuidle/cpuidle-qcom-spm.c
new file mode 100644
index 000000000000..adf91a6e4d7d
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-qcom-spm.c
@@ -0,0 +1,344 @@
+// 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,
+};
+
+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,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);