[PATCH v2] cpufreq: qcom: Read voltage LUT and populate OPP

From: Taniya Das
Date: Wed Jan 09 2019 - 03:07:52 EST


Add support to read the voltage look up table and populate OPP for all
corresponding CPUS for consumers like the energy model could use the
frequency and voltage from the OPP tables.

Tested-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Signed-off-by: Taniya Das <tdas@xxxxxxxxxxxxxx>
---
drivers/cpufreq/qcom-cpufreq-hw.c | 33 +++++++++++++++++++++++++++++++--
1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
index d83939a..18f90bb 100644
--- a/drivers/cpufreq/qcom-cpufreq-hw.c
+++ b/drivers/cpufreq/qcom-cpufreq-hw.c
@@ -10,18 +10,21 @@
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
+#include <linux/pm_opp.h>
#include <linux/slab.h>

#define LUT_MAX_ENTRIES 40U
#define LUT_SRC GENMASK(31, 30)
#define LUT_L_VAL GENMASK(7, 0)
#define LUT_CORE_COUNT GENMASK(18, 16)
+#define LUT_VOLT GENMASK(11, 0)
#define LUT_ROW_SIZE 32
#define CLK_HW_DIV 2

/* Register offsets */
#define REG_ENABLE 0x0
-#define REG_LUT_TABLE 0x110
+#define REG_FREQ_LUT 0x110
+#define REG_VOLT_LUT 0x114
#define REG_PERF_STATE 0x920

static unsigned long cpu_hw_rate, xo_rate;
@@ -75,6 +78,7 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,
void __iomem *base)
{
u32 data, src, lval, i, core_count, prev_cc = 0, prev_freq = 0, freq;
+ u32 volt;
unsigned int max_cores = cpumask_weight(policy->cpus);
struct cpufreq_frequency_table *table;

@@ -83,11 +87,16 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,
return -ENOMEM;

for (i = 0; i < LUT_MAX_ENTRIES; i++) {
- data = readl_relaxed(base + REG_LUT_TABLE + i * LUT_ROW_SIZE);
+ data = readl_relaxed(base + REG_FREQ_LUT +
+ i * LUT_ROW_SIZE);
src = FIELD_GET(LUT_SRC, data);
lval = FIELD_GET(LUT_L_VAL, data);
core_count = FIELD_GET(LUT_CORE_COUNT, data);

+ data = readl_relaxed(base + REG_VOLT_LUT +
+ i * LUT_ROW_SIZE);
+ volt = FIELD_GET(LUT_VOLT, data) * 1000;
+
if (src)
freq = xo_rate * lval / 1000;
else
@@ -98,6 +107,8 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,
table[i].frequency = CPUFREQ_ENTRY_INVALID;
} else {
table[i].frequency = freq;
+ dev_pm_opp_add(get_cpu_device(policy->cpu),
+ freq * 1000, volt);
dev_dbg(dev, "index=%d freq=%d, core_count %d\n", i,
freq, core_count);
}
@@ -116,6 +127,8 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,
if (prev_cc != max_cores) {
prev->frequency = prev_freq;
prev->flags = CPUFREQ_BOOST_FREQ;
+ dev_pm_opp_add(get_cpu_device(policy->cpu),
+ prev_freq * 1000, volt);
}

break;
@@ -127,6 +140,7 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,

table[i].frequency = CPUFREQ_TABLE_END;
policy->freq_table = table;
+ dev_pm_opp_set_sharing_cpus(get_cpu_device(policy->cpu), policy->cpus);

return 0;
}
@@ -159,10 +173,18 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
struct device *dev = &global_pdev->dev;
struct of_phandle_args args;
struct device_node *cpu_np;
+ struct device *cpu_dev;
struct resource *res;
void __iomem *base;
int ret, index;

+ cpu_dev = get_cpu_device(policy->cpu);
+ if (!cpu_dev) {
+ pr_err("%s: failed to get cpu%d device\n", __func__,
+ policy->cpu);
+ return -ENODEV;
+ }
+
cpu_np = of_cpu_device_node_get(policy->cpu);
if (!cpu_np)
return -EINVAL;
@@ -205,6 +227,12 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
goto error;
}

+ ret = dev_pm_opp_get_opp_count(cpu_dev);
+ if (ret <= 0) {
+ dev_err(cpu_dev, "OPP table is not ready\n");
+ goto error;
+ }
+
policy->fast_switch_possible = true;

return 0;
@@ -217,6 +245,7 @@ static int qcom_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy)
{
void __iomem *base = policy->driver_data - REG_PERF_STATE;

+ dev_pm_opp_remove_all_dynamic(&global_pdev->dev);
kfree(policy->freq_table);
devm_iounmap(&global_pdev->dev, base);

--
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