On 08-06-21, 18:29, Thara Gopinath wrote:
> Add interrupt support to notify the kernel of h/w initiated frequency
> throttling by LMh. Convey this to scheduler via thermal presssure
> interface.
>
> Signed-off-by: Thara Gopinath <thara.gopinath@xxxxxxxxxx>
> ---
> drivers/cpufreq/qcom-cpufreq-hw.c | 100 ++++++++++++++++++++++++++++++
> 1 file changed, 100 insertions(+)
>
> diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
> index f86859bf76f1..95e17330aa9d 100644
> --- a/drivers/cpufreq/qcom-cpufreq-hw.c
> +++ b/drivers/cpufreq/qcom-cpufreq-hw.c
> @@ -13,6 +13,7 @@
> #include <linux/of_platform.h>
> #include <linux/pm_opp.h>
> #include <linux/slab.h>
> +#include <linux/interrupt.h>
>
> #define LUT_MAX_ENTRIES 40U
> #define LUT_SRC GENMASK(31, 30)
> @@ -22,10 +23,13 @@
> #define CLK_HW_DIV 2
> #define LUT_TURBO_IND 1
>
> +#define HZ_PER_KHZ 1000
> +
> struct qcom_cpufreq_soc_data {
> u32 reg_enable;
> u32 reg_freq_lut;
> u32 reg_volt_lut;
> + u32 reg_current_vote;
> u32 reg_perf_state;
> u8 lut_row_size;
> };
> @@ -33,7 +37,11 @@ struct qcom_cpufreq_soc_data {
> struct qcom_cpufreq_data {
> void __iomem *base;
> struct resource *res;
> + struct delayed_work lmh_dcvs_poll_work;
> const struct qcom_cpufreq_soc_data *soc_data;
> + cpumask_var_t cpus;
> + unsigned long throttled_freq;
> + int lmh_dcvs_irq;
> };
>
> static unsigned long cpu_hw_rate, xo_rate;
> @@ -251,10 +259,79 @@ static void qcom_get_related_cpus(int index, struct cpumask *m)
> }
> }
>
> +static inline unsigned long qcom_lmh_vote_to_freq(u32 val)
> +{
> + return (val & 0x3FF) * 19200;
> +}
> +
> +static void qcom_lmh_dcvs_notify(struct qcom_cpufreq_data *data)
> +{
> + struct cpufreq_policy policy;
> + struct dev_pm_opp *opp;
> + struct device *dev;
> + unsigned long max_capacity, capacity, freq_hz;
> + unsigned int val, freq;
> +
> + val = readl_relaxed(data->base + data->soc_data->reg_current_vote);
> + freq = qcom_lmh_vote_to_freq(val);
> + freq_hz = freq * HZ_PER_KHZ;
> +
> + /* Do I need to calculate ceil and floor ? */
You don't know ?
> + dev = get_cpu_device(cpumask_first(data->cpus));
> + opp = dev_pm_opp_find_freq_floor(dev, &freq_hz);
> + if (IS_ERR(opp) && PTR_ERR(opp) == -ERANGE)
> + opp = dev_pm_opp_find_freq_ceil(dev, &freq_hz);
> +
> + data->throttled_freq = freq_hz / HZ_PER_KHZ;
> +
What exactly are we trying to do here ? A comment would be good as
well.
> + cpufreq_get_policy(&policy, cpumask_first(data->cpus));
> +
> + /* Update thermal pressure */
> + max_capacity = arch_scale_cpu_capacity(cpumask_first(data->cpus));
Set capacity of a single CPU from a policy ?
> + capacity = data->throttled_freq * max_capacity;
> + capacity /= policy.cpuinfo.max_freq;
> + /* Don't pass boost capacity to scheduler */
> + if (capacity > max_capacity)
> + capacity = max_capacity;
> + arch_set_thermal_pressure(data->cpus, max_capacity - capacity);
You should really be using policy->cpus instead of allocating
data->cpus..
> +}
> +
> +static void qcom_lmh_dcvs_poll(struct work_struct *work)
> +{
> + struct qcom_cpufreq_data *data;
> +
> + data = container_of(work, struct qcom_cpufreq_data, lmh_dcvs_poll_work.work);
> +
> + qcom_lmh_dcvs_notify(data);
You should really move the below stuff the disable_irq_nosync(), it
will make your life easier.
> + /**
> + * If h/w throttled frequency is higher than what cpufreq has requested for, stop
> + * polling and switch back to interrupt mechanism
> + */
> + if (data->throttled_freq >= qcom_cpufreq_hw_get(cpumask_first(data->cpus)))
> + /* Clear the existing interrupts and enable it back */
> + enable_irq(data->lmh_dcvs_irq);
> + else
> + mod_delayed_work(system_highpri_wq, &data->lmh_dcvs_poll_work,
> + msecs_to_jiffies(10));
> +}
> +
> +static irqreturn_t qcom_lmh_dcvs_handle_irq(int irq, void *data)
> +{
> + struct qcom_cpufreq_data *c_data = data;
> +
> + /* Disable interrupt and enable polling */
> + disable_irq_nosync(c_data->lmh_dcvs_irq);
> + qcom_lmh_dcvs_notify(c_data);
> + mod_delayed_work(system_highpri_wq, &c_data->lmh_dcvs_poll_work, msecs_to_jiffies(10));
> +
> + return 0;
> +}
> +
> static const struct qcom_cpufreq_soc_data qcom_soc_data = {
> .reg_enable = 0x0,
> .reg_freq_lut = 0x110,
> .reg_volt_lut = 0x114,
> + .reg_current_vote = 0x704,
Should this be a different patch ?
> .reg_perf_state = 0x920,
> .lut_row_size = 32,
> };
> @@ -285,6 +362,7 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
> void __iomem *base;
> struct qcom_cpufreq_data *data;
> int ret, index;
> + bool lmh_mitigation_enabled = false;
You just overwrite it below, no need to initialize it.
>
> cpu_dev = get_cpu_device(policy->cpu);
> if (!cpu_dev) {
> @@ -305,6 +383,8 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
>
> index = args.args[0];
>
> + lmh_mitigation_enabled = of_property_read_bool(pdev->dev.of_node, "qcom,support-lmh");
> +
> res = platform_get_resource(pdev, IORESOURCE_MEM, index);
> if (!res) {
> dev_err(dev, "failed to get mem resource %d\n", index);
> @@ -329,6 +409,11 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
> goto unmap_base;
> }
>
> + if (!alloc_cpumask_var(&data->cpus, GFP_KERNEL)) {
> + ret = -ENOMEM;
> + goto unmap_base;
> + }
> +
> data->soc_data = of_device_get_match_data(&pdev->dev);
> data->base = base;
> data->res = res;
> @@ -347,6 +432,7 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
> goto error;
> }
>
> + cpumask_copy(data->cpus, policy->cpus);
> policy->driver_data = data;
>
> ret = qcom_cpufreq_hw_read_lut(cpu_dev, policy);
> @@ -370,6 +456,20 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
> dev_warn(cpu_dev, "failed to enable boost: %d\n", ret);
> }
>
> + if (lmh_mitigation_enabled) {
Shouldn't you move the allocation and setting of data->cpus here ? I
suggest creating a separate routine for all initialization around this
stuff.
> + data->lmh_dcvs_irq = platform_get_irq(pdev, index);
> + if (data->lmh_dcvs_irq < 0) {
> + ret = data->lmh_dcvs_irq;
> + goto error;
> + }
> + ret = devm_request_irq(dev, data->lmh_dcvs_irq, qcom_lmh_dcvs_handle_irq,
> + 0, "dcvsh-irq", data);
I would rather pass policy as data here.
> + if (ret) {
> + dev_err(dev, "Error %d registering irq %x\n", ret, data->lmh_dcvs_irq);
> + goto error;
> + }
> + INIT_DEFERRABLE_WORK(&data->lmh_dcvs_poll_work, qcom_lmh_dcvs_poll);
> + }
> return 0;
> error:
> kfree(data);
--
viresh
