soc: qcom: spm: add support for voltage regulator
[linux-2.6-microblaze.git] / drivers / soc / qcom / spm.c
index b15435f..5eefaec 100644 (file)
@@ -6,20 +6,40 @@
  * SAW power controller driver
  */
 
-#include <linux/kernel.h>
+#include <linux/bitfield.h>
+#include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/linear_range.h>
 #include <linux/module.h>
-#include <linux/slab.h>
 #include <linux/of.h>
-#include <linux/err.h>
 #include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/smp.h>
+
+#include <linux/regulator/driver.h>
+
 #include <soc/qcom/spm.h>
 
+#define FIELD_SET(current, mask, val)  \
+       (((current) & ~(mask)) | FIELD_PREP((mask), (val)))
+
 #define SPM_CTL_INDEX          0x7f
 #define SPM_CTL_INDEX_SHIFT    4
 #define SPM_CTL_EN             BIT(0)
 
+/* These registers might be specific to SPM 1.1 */
+#define SPM_VCTL_VLVL                  GENMASK(7, 0)
+#define SPM_PMIC_DATA_0_VLVL           GENMASK(7, 0)
+#define SPM_PMIC_DATA_1_MIN_VSEL       GENMASK(5, 0)
+#define SPM_PMIC_DATA_1_MAX_VSEL       GENMASK(21, 16)
+
+#define SPM_1_1_AVS_CTL_AVS_ENABLED    BIT(27)
+#define SPM_AVS_CTL_MAX_VLVL           GENMASK(22, 17)
+#define SPM_AVS_CTL_MIN_VLVL           GENMASK(15, 10)
+
 enum spm_reg {
        SPM_REG_CFG,
        SPM_REG_SPM_CTL,
@@ -29,10 +49,12 @@ enum spm_reg {
        SPM_REG_PMIC_DATA_1,
        SPM_REG_VCTL,
        SPM_REG_SEQ_ENTRY,
-       SPM_REG_SPM_STS,
+       SPM_REG_STS0,
+       SPM_REG_STS1,
        SPM_REG_PMIC_STS,
        SPM_REG_AVS_CTL,
        SPM_REG_AVS_LIMIT,
+       SPM_REG_RST,
        SPM_REG_NR,
 };
 
@@ -49,11 +71,20 @@ struct spm_reg_data {
        u32 avs_limit;
        u8 seq[MAX_SEQ_DATA];
        u8 start_index[PM_SLEEP_MODE_NR];
+
+       smp_call_func_t set_vdd;
+       /* for now we support only a single range */
+       struct linear_range *range;
+       unsigned int ramp_delay;
+       unsigned int init_uV;
 };
 
 struct spm_driver_data {
        void __iomem *reg_base;
        const struct spm_reg_data *reg_data;
+       struct device *dev;
+       unsigned int volt_sel;
+       int reg_cpu;
 };
 
 static const u16 spm_reg_offset_v4_1[SPM_REG_NR] = {
@@ -189,6 +220,10 @@ static const struct spm_reg_data spm_reg_8226_cpu  = {
 
 static const u16 spm_reg_offset_v1_1[SPM_REG_NR] = {
        [SPM_REG_CFG]           = 0x08,
+       [SPM_REG_STS0]          = 0x0c,
+       [SPM_REG_STS1]          = 0x10,
+       [SPM_REG_VCTL]          = 0x14,
+       [SPM_REG_AVS_CTL]       = 0x18,
        [SPM_REG_SPM_CTL]       = 0x20,
        [SPM_REG_PMIC_DLY]      = 0x24,
        [SPM_REG_PMIC_DATA_0]   = 0x28,
@@ -196,7 +231,12 @@ static const u16 spm_reg_offset_v1_1[SPM_REG_NR] = {
        [SPM_REG_SEQ_ENTRY]     = 0x80,
 };
 
+static void smp_set_vdd_v1_1(void *data);
+
 /* SPM register data for 8064 */
+static struct linear_range spm_v1_1_regulator_range =
+       REGULATOR_LINEAR_RANGE(700000, 0, 56, 12500);
+
 static const struct spm_reg_data spm_reg_8064_cpu = {
        .reg_offset = spm_reg_offset_v1_1,
        .spm_cfg = 0x1F,
@@ -207,6 +247,10 @@ static const struct spm_reg_data spm_reg_8064_cpu = {
                0x10, 0x54, 0x30, 0x0C, 0x24, 0x30, 0x0F },
        .start_index[PM_SLEEP_MODE_STBY] = 0,
        .start_index[PM_SLEEP_MODE_SPC] = 2,
+       .set_vdd = smp_set_vdd_v1_1,
+       .range = &spm_v1_1_regulator_range,
+       .init_uV = 1300000,
+       .ramp_delay = 1250,
 };
 
 static inline void spm_register_write(struct spm_driver_data *drv,
@@ -258,6 +302,185 @@ void spm_set_low_power_mode(struct spm_driver_data *drv,
        spm_register_write_sync(drv, SPM_REG_SPM_CTL, ctl_val);
 }
 
+static int spm_set_voltage_sel(struct regulator_dev *rdev, unsigned int selector)
+{
+       struct spm_driver_data *drv = rdev_get_drvdata(rdev);
+
+       drv->volt_sel = selector;
+
+       /* Always do the SAW register writes on the corresponding CPU */
+       return smp_call_function_single(drv->reg_cpu, drv->reg_data->set_vdd, drv, true);
+}
+
+static int spm_get_voltage_sel(struct regulator_dev *rdev)
+{
+       struct spm_driver_data *drv = rdev_get_drvdata(rdev);
+
+       return drv->volt_sel;
+}
+
+static const struct regulator_ops spm_reg_ops = {
+       .set_voltage_sel        = spm_set_voltage_sel,
+       .get_voltage_sel        = spm_get_voltage_sel,
+       .list_voltage           = regulator_list_voltage_linear_range,
+       .set_voltage_time_sel   = regulator_set_voltage_time_sel,
+};
+
+static void smp_set_vdd_v1_1(void *data)
+{
+       struct spm_driver_data *drv = data;
+       unsigned int vctl, data0, data1, avs_ctl, sts;
+       unsigned int vlevel, volt_sel;
+       bool avs_enabled;
+
+       volt_sel = drv->volt_sel;
+       vlevel = volt_sel | 0x80; /* band */
+
+       avs_ctl = spm_register_read(drv, SPM_REG_AVS_CTL);
+       vctl = spm_register_read(drv, SPM_REG_VCTL);
+       data0 = spm_register_read(drv, SPM_REG_PMIC_DATA_0);
+       data1 = spm_register_read(drv, SPM_REG_PMIC_DATA_1);
+
+       avs_enabled = avs_ctl & SPM_1_1_AVS_CTL_AVS_ENABLED;
+
+       /* If AVS is enabled, switch it off during the voltage change */
+       if (avs_enabled) {
+               avs_ctl &= ~SPM_1_1_AVS_CTL_AVS_ENABLED;
+               spm_register_write(drv, SPM_REG_AVS_CTL, avs_ctl);
+       }
+
+       /* Kick the state machine back to idle */
+       spm_register_write(drv, SPM_REG_RST, 1);
+
+       vctl = FIELD_SET(vctl, SPM_VCTL_VLVL, vlevel);
+       data0 = FIELD_SET(data0, SPM_PMIC_DATA_0_VLVL, vlevel);
+       data1 = FIELD_SET(data1, SPM_PMIC_DATA_1_MIN_VSEL, volt_sel);
+       data1 = FIELD_SET(data1, SPM_PMIC_DATA_1_MAX_VSEL, volt_sel);
+
+       spm_register_write(drv, SPM_REG_VCTL, vctl);
+       spm_register_write(drv, SPM_REG_PMIC_DATA_0, data0);
+       spm_register_write(drv, SPM_REG_PMIC_DATA_1, data1);
+
+       if (read_poll_timeout_atomic(spm_register_read,
+                                    sts, sts == vlevel,
+                                    1, 200, false,
+                                    drv, SPM_REG_STS1)) {
+               dev_err_ratelimited(drv->dev, "timeout setting the voltage (%x %x)!\n", sts, vlevel);
+               goto enable_avs;
+       }
+
+       if (avs_enabled) {
+               unsigned int max_avs = volt_sel;
+               unsigned int min_avs = max(max_avs, 4U) - 4;
+
+               avs_ctl = FIELD_SET(avs_ctl, SPM_AVS_CTL_MIN_VLVL, min_avs);
+               avs_ctl = FIELD_SET(avs_ctl, SPM_AVS_CTL_MAX_VLVL, max_avs);
+               spm_register_write(drv, SPM_REG_AVS_CTL, avs_ctl);
+       }
+
+enable_avs:
+       if (avs_enabled) {
+               avs_ctl |= SPM_1_1_AVS_CTL_AVS_ENABLED;
+               spm_register_write(drv, SPM_REG_AVS_CTL, avs_ctl);
+       }
+}
+
+static int spm_get_cpu(struct device *dev)
+{
+       int cpu;
+       bool found;
+
+       for_each_possible_cpu(cpu) {
+               struct device_node *cpu_node, *saw_node;
+
+               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 == dev->of_node);
+               of_node_put(saw_node);
+               of_node_put(cpu_node);
+
+               if (found)
+                       return cpu;
+       }
+
+       /* L2 SPM is not bound to any CPU, voltage setting is not supported */
+
+       return -EOPNOTSUPP;
+}
+
+#ifdef CONFIG_REGULATOR
+static int spm_register_regulator(struct device *dev, struct spm_driver_data *drv)
+{
+       struct regulator_config config = {
+               .dev = dev,
+               .driver_data = drv,
+       };
+       struct regulator_desc *rdesc;
+       struct regulator_dev *rdev;
+       int ret;
+       bool found;
+
+       if (!drv->reg_data->set_vdd)
+               return 0;
+
+       rdesc = devm_kzalloc(dev, sizeof(*rdesc), GFP_KERNEL);
+       if (!rdesc)
+               return -ENOMEM;
+
+       rdesc->name = "spm";
+       rdesc->of_match = of_match_ptr("regulator");
+       rdesc->type = REGULATOR_VOLTAGE;
+       rdesc->owner = THIS_MODULE;
+       rdesc->ops = &spm_reg_ops;
+
+       rdesc->linear_ranges = drv->reg_data->range;
+       rdesc->n_linear_ranges = 1;
+       rdesc->n_voltages = rdesc->linear_ranges[rdesc->n_linear_ranges - 1].max_sel + 1;
+       rdesc->ramp_delay = drv->reg_data->ramp_delay;
+
+       ret = spm_get_cpu(dev);
+       if (ret < 0)
+               return ret;
+
+       drv->reg_cpu = ret;
+       dev_dbg(dev, "SAW2 bound to CPU %d\n", drv->reg_cpu);
+
+       /*
+        * Program initial voltage, otherwise registration will also try
+        * setting the voltage, which might result in undervolting the CPU.
+        */
+       drv->volt_sel = DIV_ROUND_UP(drv->reg_data->init_uV - rdesc->min_uV,
+                                    rdesc->uV_step);
+       ret = linear_range_get_selector_high(drv->reg_data->range,
+                                            drv->reg_data->init_uV,
+                                            &drv->volt_sel,
+                                            &found);
+       if (ret) {
+               dev_err(dev, "Initial uV value out of bounds\n");
+               return ret;
+       }
+
+       /* Always do the SAW register writes on the corresponding CPU */
+       smp_call_function_single(drv->reg_cpu, drv->reg_data->set_vdd, drv, true);
+
+       rdev = devm_regulator_register(dev, rdesc, &config);
+       if (IS_ERR(rdev)) {
+               dev_err(dev, "failed to register regulator\n");
+               return PTR_ERR(rdev);
+       }
+
+       return 0;
+}
+#else
+static int spm_register_regulator(struct device *dev, struct spm_driver_data *drv)
+{
+       return 0;
+}
+#endif
+
 static const struct of_device_id spm_match_table[] = {
        { .compatible = "qcom,sdm660-gold-saw2-v4.1-l2",
          .data = &spm_reg_660_gold_l2 },
@@ -308,6 +531,7 @@ static int spm_dev_probe(struct platform_device *pdev)
                return -ENODEV;
 
        drv->reg_data = match_id->data;
+       drv->dev = &pdev->dev;
        platform_set_drvdata(pdev, drv);
 
        /* Write the SPM sequences first.. */
@@ -335,7 +559,7 @@ static int spm_dev_probe(struct platform_device *pdev)
        if (drv->reg_data->reg_offset[SPM_REG_SPM_CTL])
                spm_set_low_power_mode(drv, PM_SLEEP_MODE_STBY);
 
-       return 0;
+       return spm_register_regulator(&pdev->dev, drv);
 }
 
 static struct platform_driver spm_driver = {