diff options
Diffstat (limited to 'drivers/soc/qcom/spm.c')
| -rw-r--r-- | drivers/soc/qcom/spm.c | 385 |
1 files changed, 385 insertions, 0 deletions
diff --git a/drivers/soc/qcom/spm.c b/drivers/soc/qcom/spm.c new file mode 100644 index 000000000..b04b05a09 --- /dev/null +++ b/drivers/soc/qcom/spm.c @@ -0,0 +1,385 @@ +/* + * Copyright (c) 2011-2014, The Linux Foundation. All rights reserved. + * Copyright (c) 2014,2015, Linaro Ltd. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/module.h> +#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/cpuidle.h> +#include <asm/proc-fns.h> +#include <asm/suspend.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 { + 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 DEFINE_PER_CPU(struct spm_driver_data *, cpu_spm_drv); + +typedef int (*idle_fn)(int); +static DEFINE_PER_CPU(idle_fn*, qcom_idle_ops); + +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(int cpu) +{ + int ret; + struct spm_driver_data *drv = per_cpu(cpu_spm_drv, cpu); + + 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 qcom_idle_enter(int cpu, unsigned long index) +{ + return per_cpu(qcom_idle_ops, cpu)[index](cpu); +} + +static const struct of_device_id qcom_idle_state_match[] __initconst = { + { .compatible = "qcom,idle-state-spc", .data = qcom_cpu_spc }, + { }, +}; + +static int __init qcom_cpuidle_init(struct device_node *cpu_node, int cpu) +{ + const struct of_device_id *match_id; + struct device_node *state_node; + int i; + int state_count = 1; + idle_fn idle_fns[CPUIDLE_STATE_MAX]; + idle_fn *fns; + cpumask_t mask; + bool use_scm_power_down = false; + + for (i = 0; ; i++) { + state_node = of_parse_phandle(cpu_node, "cpu-idle-states", i); + if (!state_node) + break; + + if (!of_device_is_available(state_node)) + continue; + + if (i == CPUIDLE_STATE_MAX) { + pr_warn("%s: cpuidle states reached max possible\n", + __func__); + break; + } + + match_id = of_match_node(qcom_idle_state_match, state_node); + if (!match_id) + return -ENODEV; + + idle_fns[state_count] = match_id->data; + + /* Check if any of the states allow power down */ + if (match_id->data == qcom_cpu_spc) + use_scm_power_down = true; + + state_count++; + } + + if (state_count == 1) + goto check_spm; + + fns = devm_kcalloc(get_cpu_device(cpu), state_count, sizeof(*fns), + GFP_KERNEL); + if (!fns) + return -ENOMEM; + + for (i = 1; i < state_count; i++) + fns[i] = idle_fns[i]; + + if (use_scm_power_down) { + /* We have atleast one power down mode */ + cpumask_clear(&mask); + cpumask_set_cpu(cpu, &mask); + qcom_scm_set_warm_boot_addr(cpu_resume_arm, &mask); + } + + per_cpu(qcom_idle_ops, cpu) = fns; + + /* + * SPM probe for the cpu should have happened by now, if the + * SPM device does not exist, return -ENXIO to indicate that the + * cpu does not support idle states. + */ +check_spm: + return per_cpu(cpu_spm_drv, cpu) ? 0 : -ENXIO; +} + +static struct cpuidle_ops qcom_cpuidle_ops __initdata = { + .suspend = qcom_idle_enter, + .init = qcom_cpuidle_init, +}; + +CPUIDLE_METHOD_OF_DECLARE(qcom_idle_v1, "qcom,kpss-acc-v1", &qcom_cpuidle_ops); +CPUIDLE_METHOD_OF_DECLARE(qcom_idle_v2, "qcom,kpss-acc-v2", &qcom_cpuidle_ops); + +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; + + 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; + + drv = spm_get_drv(pdev, &cpu); + if (!drv) + return -EINVAL; + + 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; + + /* 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); + + per_cpu(cpu_spm_drv, cpu) = drv; + + return 0; +} + +static struct platform_driver spm_driver = { + .probe = spm_dev_probe, + .driver = { + .name = "saw", + .of_match_table = spm_match_table, + }, +}; +module_platform_driver(spm_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("SAW power controller driver"); +MODULE_ALIAS("platform:saw"); |