msm: krait-regulator: enable intelligent phase control
Simulation results have shown that the PMIC phase can be optimally
managed based on coefficients calculated when the cpu voltage or
load changes.
These coefficients and their aggregation do not translate to
any physical units, but indicate the power required to run the cpus.
Compare these values with phase count thresholds to decide the
number of phases to turn on. If the number of phases turn out to
be higher than the number of cpus online, restrict the phases to
the number of cpus online.
Also avoid calculating these coefficients and setting phases until
late in the init sequence, that way initializations of cpus brought
up during boot would not lower the phase count and cause a crash.
Change-Id: I37401fe9bf8bbe244e85933c27c4638bbcbaa735
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
diff --git a/arch/arm/mach-msm/krait-regulator.c b/arch/arm/mach-msm/krait-regulator.c
index 953f941d..c714a85 100644
--- a/arch/arm/mach-msm/krait-regulator.c
+++ b/arch/arm/mach-msm/krait-regulator.c
@@ -61,9 +61,7 @@
#define PMIC_VOLTAGE_MAX 1355000
#define LV_RANGE_STEP 5000
-#define LOAD_PER_PHASE 3200000
-
-#define CORE_VOLTAGE_MIN 900000
+#define CORE_VOLTAGE_BOOTUP 900000
#define KRAIT_LDO_VOLTAGE_MIN 465000
#define KRAIT_LDO_VOLTAGE_OFFSET 465000
@@ -146,7 +144,10 @@
* regulator's callback functions to prevent
* simultaneous updates to the pmic's phase
* voltage.
- * @apcs_gcc_base virtual address of the APCS GCC registers
+ * @apcs_gcc_base: virtual address of the APCS GCC registers
+ * @manage_phases: begin phase control
+ * @pfm_threshold: the sum of coefficients below which PFM can be
+ * enabled
*/
struct pmic_gang_vreg {
const char *name;
@@ -159,6 +160,8 @@
bool retention_enabled;
bool use_phase_switching;
void __iomem *apcs_gcc_base;
+ bool manage_phases;
+ int pfm_threshold;
};
static struct pmic_gang_vreg *the_gang;
@@ -175,7 +178,7 @@
const char *name;
struct pmic_gang_vreg *pvreg;
int uV;
- int load_uA;
+ int load;
enum krait_supply_mode mode;
void __iomem *reg_base;
void __iomem *mdd_base;
@@ -185,6 +188,8 @@
int ldo_threshold_uV;
int ldo_delta_uV;
int cpu_num;
+ int coeff1;
+ int coeff2;
bool online;
};
@@ -293,6 +298,211 @@
return 0;
}
+#define COEFF2_UV_THRESHOLD 850000
+static int get_coeff2(int krait_uV)
+{
+ int coeff2 = 0;
+ int krait_mV = krait_uV / 1000;
+
+ if (krait_uV <= COEFF2_UV_THRESHOLD)
+ coeff2 = (612229 * krait_mV) / 1000 - 211258;
+ else
+ coeff2 = (892564 * krait_mV) / 1000 - 449543;
+
+ return coeff2;
+}
+
+static int get_coeff1(int actual_uV, int requested_uV, int load)
+{
+ int ratio = actual_uV * 1000 / requested_uV;
+ int coeff1 = 330 * load + (load * 673 * ratio / 1000);
+
+ return coeff1;
+}
+
+static int get_coeff_total(struct krait_power_vreg *from)
+{
+ int coeff_total = 0;
+ struct krait_power_vreg *kvreg;
+ struct pmic_gang_vreg *pvreg = from->pvreg;
+
+ list_for_each_entry(kvreg, &pvreg->krait_power_vregs, link) {
+ if (!kvreg->online)
+ continue;
+
+ if (kvreg->mode == LDO_MODE) {
+ kvreg->coeff1 =
+ get_coeff1(kvreg->uV - kvreg->ldo_delta_uV,
+ kvreg->uV, kvreg->load);
+ kvreg->coeff2 =
+ get_coeff2(kvreg->uV - kvreg->ldo_delta_uV);
+ } else {
+ kvreg->coeff1 =
+ get_coeff1(pvreg->pmic_vmax_uV,
+ kvreg->uV, kvreg->load);
+ kvreg->coeff2 = get_coeff2(pvreg->pmic_vmax_uV);
+ }
+ coeff_total += kvreg->coeff1 + kvreg->coeff2;
+ }
+
+ return coeff_total;
+}
+
+static int set_pmic_gang_phases(struct pmic_gang_vreg *pvreg, int phase_count)
+{
+ pr_debug("programming phase_count = %d\n", phase_count);
+ if (pvreg->use_phase_switching)
+ /*
+ * note the PMIC sets the phase count to one more than
+ * the value in the register - hence subtract 1 from it
+ */
+ return msm_spm_apcs_set_phase(phase_count - 1);
+ else
+ return 0;
+}
+
+static int num_online(struct pmic_gang_vreg *pvreg)
+{
+ int online_total = 0;
+ struct krait_power_vreg *kvreg;
+
+ list_for_each_entry(kvreg, &pvreg->krait_power_vregs, link) {
+ if (kvreg->online)
+ online_total++;
+ }
+ return online_total;
+}
+
+#define PMIC_FTS_MODE_PFM 0x00
+#define PMIC_FTS_MODE_PWM 0x80
+#define ONE_PHASE_COEFF 1000000
+#define TWO_PHASE_COEFF 2000000
+
+#define PHASE_SETTLING_TIME_US 10
+static unsigned int pmic_gang_set_phases(struct krait_power_vreg *from,
+ int coeff_total)
+{
+ struct pmic_gang_vreg *pvreg = from->pvreg;
+ int phase_count;
+ int rc = 0;
+ int n_online = num_online(pvreg);
+
+ if (pvreg->manage_phases == false)
+ return 0;
+
+ /* First check if the coeff is low for PFM mode */
+ if (coeff_total < pvreg->pfm_threshold && n_online == 1) {
+ if (!pvreg->pfm_mode) {
+ rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PFM);
+ if (rc) {
+ pr_err("%s PFM en failed coeff_t %d rc = %d\n",
+ from->name, coeff_total, rc);
+ return rc;
+ } else {
+ pvreg->pfm_mode = true;
+ }
+ }
+ return rc;
+ }
+
+ /* coeff is high switch to PWM mode before changing phases */
+ if (pvreg->pfm_mode) {
+ rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PWM);
+ if (rc) {
+ pr_err("%s PFM exit failed load %d rc = %d\n",
+ from->name, coeff_total, rc);
+ return rc;
+ } else {
+ pvreg->pfm_mode = false;
+ }
+ }
+
+ /* calculate phases */
+ if (coeff_total < ONE_PHASE_COEFF)
+ phase_count = 1;
+ else if (coeff_total < TWO_PHASE_COEFF)
+ phase_count = 2;
+ else
+ phase_count = 4;
+
+ /* don't increase the phase count higher than number of online cpus */
+ if (phase_count > n_online)
+ phase_count = n_online;
+
+ if (phase_count != pvreg->pmic_phase_count) {
+ rc = set_pmic_gang_phases(pvreg, phase_count);
+ if (rc < 0) {
+ pr_err("%s failed set phase %d rc = %d\n",
+ from->name, phase_count, rc);
+ return rc;
+ }
+
+ /* complete the writes before the delay */
+ mb();
+
+ /*
+ * delay until the phases are settled when
+ * the count is raised
+ */
+ if (phase_count > pvreg->pmic_phase_count)
+ udelay(PHASE_SETTLING_TIME_US);
+
+ pvreg->pmic_phase_count = phase_count;
+ }
+
+ return rc;
+}
+
+static unsigned int _get_optimum_mode(struct regulator_dev *rdev,
+ int input_uV, int output_uV, int load)
+{
+ struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
+ int coeff_total;
+ int rc;
+
+ coeff_total = get_coeff_total(kvreg);
+
+ rc = pmic_gang_set_phases(kvreg, coeff_total);
+ if (rc < 0) {
+ dev_err(&rdev->dev, "%s failed set mode %d rc = %d\n",
+ kvreg->name, coeff_total, rc);
+ }
+
+ return kvreg->mode;
+}
+
+static unsigned int krait_power_get_optimum_mode(struct regulator_dev *rdev,
+ int input_uV, int output_uV, int load_uA)
+{
+ struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
+ struct pmic_gang_vreg *pvreg = kvreg->pvreg;
+ int rc;
+
+ mutex_lock(&pvreg->krait_power_vregs_lock);
+ kvreg->load = load_uA;
+ if (!kvreg->online) {
+ mutex_unlock(&pvreg->krait_power_vregs_lock);
+ return kvreg->mode;
+ }
+
+ rc = _get_optimum_mode(rdev, input_uV, output_uV, load_uA);
+ mutex_unlock(&pvreg->krait_power_vregs_lock);
+
+ return rc;
+}
+
+static int krait_power_set_mode(struct regulator_dev *rdev, unsigned int mode)
+{
+ return 0;
+}
+
+static unsigned int krait_power_get_mode(struct regulator_dev *rdev)
+{
+ struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
+
+ return kvreg->mode;
+}
+
static int switch_to_using_hs(struct krait_power_vreg *kvreg)
{
if (kvreg->mode == HS_MODE)
@@ -368,19 +578,6 @@
return 0;
}
-static int set_pmic_gang_phases(struct pmic_gang_vreg *pvreg, int phase_count)
-{
- pr_debug("programming phase_count = %d\n", phase_count);
- if (pvreg->use_phase_switching)
- /*
- * note the PMIC sets the phase count to one more than
- * the value in the register - hence subtract 1 from it
- */
- return msm_spm_apcs_set_phase(phase_count - 1);
- else
- return 0;
-}
-
static int set_pmic_gang_voltage(struct pmic_gang_vreg *pvreg, int uV)
{
int setpoint;
@@ -524,46 +721,6 @@
return rc;
}
-#define PHASE_SETTLING_TIME_US 10
-static unsigned int pmic_gang_set_phases(struct krait_power_vreg *from,
- int load_uA)
-{
- struct pmic_gang_vreg *pvreg = from->pvreg;
- int phase_count = DIV_ROUND_UP(load_uA, LOAD_PER_PHASE);
- int rc = 0;
-
- if (phase_count <= 0)
- phase_count = 1;
-
- /* Increase phases if it is less than the number of cpus online */
- if (phase_count < num_online_cpus()) {
- phase_count = num_online_cpus();
- }
-
- if (phase_count != pvreg->pmic_phase_count) {
- rc = set_pmic_gang_phases(pvreg, phase_count);
- if (rc < 0) {
- dev_err(&from->rdev->dev,
- "%s failed set phase %d rc = %d\n",
- pvreg->name, phase_count, rc);
- return rc;
- }
-
- /* complete the writes before the delay */
- mb();
-
- /*
- * delay until the phases are settled when
- * the count is raised
- */
- if (phase_count > pvreg->pmic_phase_count)
- udelay(PHASE_SETTLING_TIME_US);
-
- pvreg->pmic_phase_count = phase_count;
- }
- return rc;
-}
-
static int krait_power_get_voltage(struct regulator_dev *rdev)
{
struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
@@ -590,21 +747,6 @@
return vmax;
}
-static int get_total_load(struct krait_power_vreg *from)
-{
- int load_total = 0;
- struct krait_power_vreg *kvreg;
- struct pmic_gang_vreg *pvreg = from->pvreg;
-
- list_for_each_entry(kvreg, &pvreg->krait_power_vregs, link) {
- if (!kvreg->online)
- continue;
- load_total += kvreg->load_uA;
- }
-
- return load_total;
-}
-
#define ROUND_UP_VOLTAGE(v, res) (DIV_ROUND_UP(v, res) * res)
static int _set_voltage(struct regulator_dev *rdev,
int orig_krait_uV, int requested_uV)
@@ -613,6 +755,7 @@
struct pmic_gang_vreg *pvreg = kvreg->pvreg;
int rc;
int vmax;
+ int coeff_total;
pr_debug("%s: %d to %d\n", kvreg->name, orig_krait_uV, requested_uV);
/*
@@ -636,6 +779,10 @@
kvreg->name, requested_uV, orig_krait_uV, rc);
}
+ coeff_total = get_coeff_total(kvreg);
+ /* adjust the phases since coeff2 would have changed */
+ rc = pmic_gang_set_phases(kvreg, coeff_total);
+
return rc;
}
@@ -670,89 +817,6 @@
return rc;
}
-#define PMIC_FTS_MODE_PFM 0x00
-#define PMIC_FTS_MODE_PWM 0x80
-#define PFM_LOAD_UA 500000
-static unsigned int _get_optimum_mode(struct regulator_dev *rdev,
- int input_uV, int output_uV, int load_uA)
-{
- struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
- struct pmic_gang_vreg *pvreg = kvreg->pvreg;
- int rc;
- int load_total_uA;
-
- load_total_uA = get_total_load(kvreg);
-
- if (load_total_uA < PFM_LOAD_UA) {
- if (!pvreg->pfm_mode) {
- rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PFM);
- if (rc) {
- dev_err(&rdev->dev,
- "%s enter PFM failed load %d rc = %d\n",
- kvreg->name, load_total_uA, rc);
- goto out;
- } else {
- pvreg->pfm_mode = true;
- }
- }
- return kvreg->mode;
- }
-
- if (pvreg->pfm_mode) {
- rc = msm_spm_enable_fts_lpm(PMIC_FTS_MODE_PWM);
- if (rc) {
- dev_err(&rdev->dev,
- "%s exit PFM failed load %d rc = %d\n",
- kvreg->name, load_total_uA, rc);
- goto out;
- } else {
- pvreg->pfm_mode = false;
- }
- }
-
- rc = pmic_gang_set_phases(kvreg, load_total_uA);
- if (rc < 0) {
- dev_err(&rdev->dev, "%s failed set mode %d rc = %d\n",
- kvreg->name, load_total_uA, rc);
- goto out;
- }
-
-out:
- return kvreg->mode;
-}
-
-static unsigned int krait_power_get_optimum_mode(struct regulator_dev *rdev,
- int input_uV, int output_uV, int load_uA)
-{
- struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
- struct pmic_gang_vreg *pvreg = kvreg->pvreg;
- int rc;
-
- mutex_lock(&pvreg->krait_power_vregs_lock);
- kvreg->load_uA = load_uA;
- if (!kvreg->online) {
- mutex_unlock(&pvreg->krait_power_vregs_lock);
- return kvreg->mode;
- }
-
- rc = _get_optimum_mode(rdev, input_uV, output_uV, load_uA);
- mutex_unlock(&pvreg->krait_power_vregs_lock);
-
- return rc;
-}
-
-static int krait_power_set_mode(struct regulator_dev *rdev, unsigned int mode)
-{
- return 0;
-}
-
-static unsigned int krait_power_get_mode(struct regulator_dev *rdev)
-{
- struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
-
- return kvreg->mode;
-}
-
static int krait_power_is_enabled(struct regulator_dev *rdev)
{
struct krait_power_vreg *kvreg = rdev_get_drvdata(rdev);
@@ -769,7 +833,7 @@
mutex_lock(&pvreg->krait_power_vregs_lock);
__krait_power_mdd_enable(kvreg, true);
kvreg->online = true;
- rc = _get_optimum_mode(rdev, kvreg->uV, kvreg->uV, kvreg->load_uA);
+ rc = _get_optimum_mode(rdev, kvreg->uV, kvreg->uV, kvreg->load);
if (rc < 0)
goto en_err;
/*
@@ -791,8 +855,7 @@
mutex_lock(&pvreg->krait_power_vregs_lock);
kvreg->online = false;
- rc = _get_optimum_mode(rdev, kvreg->uV, kvreg->uV,
- kvreg->load_uA);
+ rc = _get_optimum_mode(rdev, kvreg->uV, kvreg->uV, kvreg->load);
if (rc < 0)
goto dis_err;
@@ -1012,7 +1075,7 @@
kvreg->desc.ops = &krait_power_ops;
kvreg->desc.type = REGULATOR_VOLTAGE;
kvreg->desc.owner = THIS_MODULE;
- kvreg->uV = CORE_VOLTAGE_MIN;
+ kvreg->uV = CORE_VOLTAGE_BOOTUP;
kvreg->mode = HS_MODE;
kvreg->desc.ops = &krait_power_ops;
kvreg->headroom_uV = headroom_uV;
@@ -1111,6 +1174,7 @@
{
int rc;
bool use_phase_switching = false;
+ int pfm_threshold;
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct pmic_gang_vreg *pvreg;
@@ -1123,6 +1187,13 @@
use_phase_switching = of_property_read_bool(node,
"qcom,use-phase-switching");
+
+ rc = of_property_read_u32(node, "qcom,pfm-threshold", &pfm_threshold);
+ if (rc < 0) {
+ dev_err(dev, "pfm-threshold missing rc=%d, pfm disabled\n", rc);
+ return -EINVAL;
+ }
+
pvreg = devm_kzalloc(&pdev->dev,
sizeof(struct pmic_gang_vreg), GFP_KERNEL);
if (!pvreg) {
@@ -1148,6 +1219,7 @@
pvreg->retention_enabled = true;
pvreg->pmic_min_uV_for_retention = INT_MAX;
pvreg->use_phase_switching = use_phase_switching;
+ pvreg->pfm_threshold = pfm_threshold;
mutex_init(&pvreg->krait_power_vregs_lock);
INIT_LIST_HEAD(&pvreg->krait_power_vregs);
@@ -1236,6 +1308,14 @@
base_ptr + APC_PWR_GATE_CTL);
}
+static int __devinit begin_pmic_phase_management(void)
+{
+ if (the_gang != NULL)
+ the_gang->manage_phases = true;
+ return 0;
+}
+late_initcall(begin_pmic_phase_management);
+
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("KRAIT POWER regulator driver");
MODULE_VERSION("1.0");