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

Taniya Das
2019-01-17T07:04:34Z

Thanks for the patch, would incorporate in the next patch series.

On 1/15/2019 5:59 AM, Matthias Kaehlcke wrote:
> Hi Taniya,
>
> On Wed, Jan 09, 2019 at 01:37:28PM +0530, Taniya Das wrote:
>> 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@chromium.org>
>> Signed-off-by: Taniya Das <tdas@codeaurora.org>
>> ---
>> 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);
>
> With this patch I get the following message on a SDM845 platform:
>
> [ 0.847515] cpu cpu0: _opp_is_duplicate: duplicate OPPs detected. Existing: freq: 1766400000, volt: 804000, enabled: 1. New: freq: 1766400000, volt: 804000, enabled: 1
>
> A LUT that doesn't end with a boost frequency isn't handled
> properly. The below patch fixes this.
>
> Cheers
>
> Matthias
>
>
> From 481d7d6b190285c95f20e9e1b5ccd5c6b9910a0d Mon Sep 17 00:00:00 2001
> From: Matthias Kaehlcke <mka@chromium.org>
> Date: Mon, 14 Jan 2019 15:54:54 -0800
> Subject: [PATCH] cpufreq: qcom-hw: Don't add duplicate OPPs
>
> Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
> ---
> drivers/cpufreq/qcom-cpufreq-hw.c | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index 41557329777e5a..314c8d29276b5e 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -103,15 +103,14 @@ static int qcom_cpufreq_hw_read_lut(struct device *dev,
> else
> freq = cpu_hw_rate / 1000;
>
> - /* Ignore boosts in the middle of the table */
> - if (core_count != max_cores) {
> - table[i].frequency = CPUFREQ_ENTRY_INVALID;
> - } else {
> + if ((freq != prev_freq) && (core_count == max_cores)) {
> table[i].frequency = freq;
> dev_pm_opp_add(get_cpu_device(policy->cpu),
> - freq * 1000, volt);
> + freq * 1000, volt);
> dev_dbg(dev, "index=%d freq=%d, core_count %d\n", i,
> freq, core_count);
> + } else {
> + table[i].frequency = CPUFREQ_ENTRY_INVALID;
> }
>
> /*
>
>

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