Re: [PATCH 1/2] PM / devfreq: exynos-ppmu: Add the support of PPMUv2 for Exynos5433

Krzysztof Kozlowski
2015-07-23T07:28:56Z

On 23.07.2015 10:57, Chanwoo Choi wrote:
> This patch adds the support for PPMU (Platform Performance Monitoring Unit)
> version 2.0 for Exynos5433 SoC. Exynos5433 SoC must need PPMUv2 which is
> quite different from PPMUv1.1. The exynos-ppmu.c driver supports both PPMUv1.1
> and PPMUv2.
>
> Cc: MyungJoo Ham <myungjoo.ham@samsung.com>
> Cc: Kyungmin Park <kyungmin.park@samsung.com>
> Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

Hi,

Few comments at the end.

> ---
> drivers/devfreq/event/exynos-ppmu.c | 168 ++++++++++++++++++++++++++++++++++--
> drivers/devfreq/event/exynos-ppmu.h | 70 +++++++++++++++
> 2 files changed, 231 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
> index 7d99d13bacd8..6066dc18fc73 100644
> --- a/drivers/devfreq/event/exynos-ppmu.c
> +++ b/drivers/devfreq/event/exynos-ppmu.c
> @@ -1,7 +1,7 @@
> /*
> * exynos_ppmu.c - EXYNOS PPMU (Platform Performance Monitoring Unit) support
> *
> - * Copyright (c) 2014 Samsung Electronics Co., Ltd.
> + * Copyright (c) 2014-2015 Samsung Electronics Co., Ltd.
> * Author : Chanwoo Choi <cw00.choi@samsung.com>
> *
> * This program is free software; you can redistribute it and/or modify
> @@ -82,6 +82,15 @@ struct __exynos_ppmu_events {
> PPMU_EVENT(mscl),
> PPMU_EVENT(fimd0x),
> PPMU_EVENT(fimd1x),
> +
> + /* Only for Exynos5433 SoCs */
> + PPMU_EVENT(d0-cpu),
> + PPMU_EVENT(d0-general),
> + PPMU_EVENT(d0-rt),
> + PPMU_EVENT(d1-cpu),
> + PPMU_EVENT(d1-general),
> + PPMU_EVENT(d1-rt),
> +
> { /* sentinel */ },
> };
>
> @@ -96,6 +105,9 @@ static int exynos_ppmu_find_ppmu_id(struct devfreq_event_dev *edev)
> return -EINVAL;
> }
>
> +/*
> + * The devfreq-event ops structure for PPMU v1.1
> + */
> static int exynos_ppmu_disable(struct devfreq_event_dev *edev)
> {
> struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
> @@ -200,6 +212,153 @@ static const struct devfreq_event_ops exynos_ppmu_ops = {
> .get_event = exynos_ppmu_get_event,
> };
>
> +/*
> + * The devfreq-event ops structure for PPMU v2.0
> + */
> +static int exynos_ppmu_v2_disable(struct devfreq_event_dev *edev)
> +{
> + struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
> + u32 pmnc, clear;
> +
> + /* Disable all counters */
> + clear = (PPMU_CCNT_MASK | PPMU_PMCNT0_MASK | PPMU_PMCNT1_MASK
> + | PPMU_PMCNT2_MASK | PPMU_PMCNT3_MASK);
> +
> + __raw_writel(clear, info->ppmu.base + PPMUv2_FLAG);
> + __raw_writel(clear, info->ppmu.base + PPMUv2_INTENC);
> + __raw_writel(clear, info->ppmu.base + PPMUv2_CNTENC);
> + __raw_writel(clear, info->ppmu.base + PPMUv2_CNT_RESET);
> +
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CIG_CFG0);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CIG_CFG1);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CIG_CFG2);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CIG_RESULT);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CNT_AUTO);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CH_EV0_TYPE);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CH_EV1_TYPE);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CH_EV2_TYPE);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_CH_EV3_TYPE);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_SM_ID_V);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_SM_ID_A);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_SM_OTHERS_V);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_SM_OTHERS_A);
> + __raw_writel(0x0, info->ppmu.base + PPMUv2_INTERRUPT_RESET);
> +
> + /* Disable PPMU */
> + pmnc = __raw_readl(info->ppmu.base + PPMUv2_PMNC);
> + pmnc &= ~PPMU_PMNC_ENABLE_MASK;
> + __raw_writel(pmnc, info->ppmu.base + PPMUv2_PMNC);
> +
> + return 0;
> +}
> +
> +static int exynos_ppmu_v2_set_event(struct devfreq_event_dev *edev)
> +{
> + struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
> + int id = exynos_ppmu_find_ppmu_id(edev);
> + u32 pmnc, cntens;
> +
> + /* Enable all counters */
> + cntens = __raw_readl(info->ppmu.base + PPMUv2_CNTENS);
> + cntens |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
> + __raw_writel(cntens, info->ppmu.base + PPMUv2_CNTENS);
> +
> + /* Set the event of Read/Write data count */
> + switch (id) {
> + case PPMU_PMNCNT0:
> + case PPMU_PMNCNT1:
> + case PPMU_PMNCNT2:
> + __raw_writel(PPMUv2_RO_DATA_CNT | PPMUv2_WO_DATA_CNT,
> + info->ppmu.base + PPMUv2_CH_EVx_TYPE(id));
> + break;
> + case PPMU_PMNCNT3:
> + __raw_writel(PPMUv2_EVT3_RW_DATA_CNT,
> + info->ppmu.base + PPMUv2_CH_EVx_TYPE(id));
> + break;
> + }
> +
> + /* Reset cycle counter/performance counter and enable PPMU */
> + pmnc = __raw_readl(info->ppmu.base + PPMUv2_PMNC);
> + pmnc &= ~(PPMU_PMNC_ENABLE_MASK
> + | PPMU_PMNC_COUNTER_RESET_MASK
> + | PPMU_PMNC_CC_RESET_MASK
> + | PPMU_PMNC_CC_DIVIDER_MASK
> + | PPMUv2_PMNC_START_MODE_MASK);
> + pmnc |= (PPMU_ENABLE << PPMU_PMNC_ENABLE_SHIFT);
> + pmnc |= (PPMU_ENABLE << PPMU_PMNC_COUNTER_RESET_SHIFT);
> + pmnc |= (PPMU_ENABLE << PPMU_PMNC_CC_RESET_SHIFT);
> + pmnc |= (PPMUv2_MODE_MANUAL << PPMUv2_PMNC_START_MODE_SHIFT);
> + __raw_writel(pmnc, info->ppmu.base + PPMUv2_PMNC);
> +
> + return 0;
> +}
> +
> +static int exynos_ppmu_v2_get_event(struct devfreq_event_dev *edev,
> + struct devfreq_event_data *edata)
> +{
> + struct exynos_ppmu *info = devfreq_event_get_drvdata(edev);
> + int id = exynos_ppmu_find_ppmu_id(edev);
> + u32 pmnc, cntenc;
> + u32 pmcnt_high, pmcnt_low;
> + u64 load_count = 0;
> +
> + /* Disable PPMU */
> + pmnc = __raw_readl(info->ppmu.base + PPMUv2_PMNC);
> + pmnc &= ~PPMU_PMNC_ENABLE_MASK;
> + __raw_writel(pmnc, info->ppmu.base + PPMUv2_PMNC);
> +
> + /* Read cycle count and performance count */
> + edata->total_count = __raw_readl(info->ppmu.base + PPMUv2_CCNT);
> +
> + switch (id) {
> + case PPMU_PMNCNT0:
> + case PPMU_PMNCNT1:
> + case PPMU_PMNCNT2:
> + load_count = __raw_readl(info->ppmu.base + PPMUv2_PMNCT(id));
> + break;
> + case PPMU_PMNCNT3:
> + pmcnt_high = __raw_readl(info->ppmu.base + PPMUv2_PMCNT3_HIGH);
> + pmcnt_low = __raw_readl(info->ppmu.base + PPMUv2_PMCNT3_LOW);
> + load_count = (u64)((pmcnt_high & 0xff) << 32) + (u64)pmcnt_low;
> + break;
> + }
> + edata->load_count = load_count;
> +
> + /* Disable all counters */
> + cntenc = __raw_readl(info->ppmu.base + PPMUv2_CNTENC);
> + cntenc |= (PPMU_CCNT_MASK | (PPMU_ENABLE << id));
> + __raw_writel(cntenc, info->ppmu.base + PPMUv2_CNTENC);
> +
> + dev_dbg(&edev->dev, "%25s (load: %ld / %ld)\n", edev->desc->name,
> + edata->load_count, edata->total_count);
> + return 0;
> +}
> +
> +static struct devfreq_event_ops exynos_ppmu_v2_ops = {

This can be const.

> + .disable = exynos_ppmu_v2_disable,
> + .set_event = exynos_ppmu_v2_set_event,
> + .get_event = exynos_ppmu_v2_get_event,
> +};
> +
> +static struct of_device_id exynos_ppmu_id_match[] = {

In the previous patch this was not present but now it can be made 'const'.

> + {
> + .compatible = "samsung,exynos-ppmu",
> + .data = (void *)&exynos_ppmu_ops,
> + }, {
> + .compatible = "samsung,exynos-ppmu-v2",
> + .data = (void *)&exynos_ppmu_v2_ops,
> + },
> + { /* sentinel */ },
> +};
> +
> +static struct devfreq_event_ops *exynos_bus_get_ops(struct device_node *np)
> +{
> + const struct of_device_id *match;
> +
> + match = of_match_node(exynos_ppmu_id_match, np);
> + return (struct devfreq_event_ops *)match->data;
> +}
> +
> static int of_get_devfreq_events(struct device_node *np,
> struct exynos_ppmu *info)
> {
> @@ -238,7 +397,7 @@ static int of_get_devfreq_events(struct device_node *np,
> continue;
> }
>
> - desc[j].ops = &exynos_ppmu_ops;
> + desc[j].ops = exynos_bus_get_ops(np);

So for each ops callback (get/set/disable) you will have another layer
of indirection where you will be matching the device each time?

That seems like a waste of CPU time. Just match it once here and use
either old ops or new ops_v2.

> desc[j].driver_data = info;
>
> of_property_read_string(node, "event-name", &desc[j].name);
> @@ -354,11 +513,6 @@ static int exynos_ppmu_remove(struct platform_device *pdev)
> return 0;
> }
>
> -static struct of_device_id exynos_ppmu_id_match[] = {
> - { .compatible = "samsung,exynos-ppmu", },
> - { /* sentinel */ },
> -};
> -
> static struct platform_driver exynos_ppmu_driver = {
> .probe = exynos_ppmu_probe,
> .remove = exynos_ppmu_remove,
> diff --git a/drivers/devfreq/event/exynos-ppmu.h b/drivers/devfreq/event/exynos-ppmu.h
> index 4e831d48c138..9a7cf6394f37 100644
> --- a/drivers/devfreq/event/exynos-ppmu.h
> +++ b/drivers/devfreq/event/exynos-ppmu.h
> @@ -26,6 +26,9 @@ enum ppmu_counter {
> PPMU_PMNCNT_MAX,
> };
>
> +/***
> + * PPMUv1.1 Definitions
> + */
> enum ppmu_event_type {
> PPMU_RO_BUSY_CYCLE_CNT = 0x0,
> PPMU_WO_BUSY_CYCLE_CNT = 0x1,
> @@ -90,4 +93,71 @@ enum ppmu_reg {
> #define PPMU_PMNCT(x) (PPMU_PMCNT0 + (0x10 * x))
> #define PPMU_BEVTxSEL(x) (PPMU_BEVT0SEL + (0x100 * x))
>
> +/***
> + * PPMUv2.0 definitions
> + */
> +enum ppmuv2_mode {
> + PPMUv2_MODE_MANUAL = 0,
> + PPMUv2_MODE_AUTO = 1,
> + PPMUv2_MODE_CIG = 2, /* CIG (Conditional Interrupt Generation) */

Mixing lower-upper case looks odd to me. How about:
PPMU2_MODE_MANUAL = 0,
or
PPMU_V2_MODE_MANUAL = 0,
?

(here and everywhere below)

Best regards,
Krzysztof

> +};
> +
> +enum ppmuv2_event_type {
> + PPMUv2_RO_DATA_CNT = 0x4,
> + PPMUv2_WO_DATA_CNT = 0x5,
> +
> + PPMUv2_EVT3_RW_DATA_CNT = 0x22, /* Only for Event3 */
> +};
> +
> +enum ppmuv2_reg {
> + /* PPC control register */
> + PPMUv2_PMNC = 0x04,
> + PPMUv2_CNTENS = 0x08,
> + PPMUv2_CNTENC = 0x0c,
> + PPMUv2_INTENS = 0x10,
> + PPMUv2_INTENC = 0x14,
> + PPMUv2_FLAG = 0x18,
> +
> + /* Cycle Counter and Performance Event Counter Register */
> + PPMUv2_CCNT = 0x48,
> + PPMUv2_PMCNT0 = 0x34,
> + PPMUv2_PMCNT1 = 0x38,
> + PPMUv2_PMCNT2 = 0x3c,
> + PPMUv2_PMCNT3_LOW = 0x40,
> + PPMUv2_PMCNT3_HIGH = 0x44,
> +
> + /* Bus Event Generator */
> + PPMUv2_CIG_CFG0 = 0x1c,
> + PPMUv2_CIG_CFG1 = 0x20,
> + PPMUv2_CIG_CFG2 = 0x24,
> + PPMUv2_CIG_RESULT = 0x28,
> + PPMUv2_CNT_RESET = 0x2c,
> + PPMUv2_CNT_AUTO = 0x30,
> + PPMUv2_CH_EV0_TYPE = 0x200,
> + PPMUv2_CH_EV1_TYPE = 0x204,
> + PPMUv2_CH_EV2_TYPE = 0x208,
> + PPMUv2_CH_EV3_TYPE = 0x20c,
> + PPMUv2_SM_ID_V = 0x220,
> + PPMUv2_SM_ID_A = 0x224,
> + PPMUv2_SM_OTHERS_V = 0x228,
> + PPMUv2_SM_OTHERS_A = 0x22c,
> + PPMUv2_INTERRUPT_RESET = 0x260,
> +};
> +
> +/* PMNC register */
> +#define PPMUv2_PMNC_START_MODE_SHIFT 20
> +#define PPMUv2_PMNC_START_MODE_MASK (0x3 << PPMUv2_PMNC_START_MODE_SHIFT)
> +
> +#define PPMU_PMNC_CC_RESET_SHIFT 2
> +#define PPMU_PMNC_COUNTER_RESET_SHIFT 1
> +#define PPMU_PMNC_ENABLE_SHIFT 0
> +#define PPMU_PMNC_START_MODE_MASK BIT(16)
> +#define PPMU_PMNC_CC_DIVIDER_MASK BIT(3)
> +#define PPMU_PMNC_CC_RESET_MASK BIT(2)
> +#define PPMU_PMNC_COUNTER_RESET_MASK BIT(1)
> +#define PPMU_PMNC_ENABLE_MASK BIT(0)
> +
> +#define PPMUv2_PMNCT(x) (PPMUv2_PMCNT0 + (0x4 * x))
> +#define PPMUv2_CH_EVx_TYPE(x) (PPMUv2_CH_EV0_TYPE + (0x4 * x))
> +
> #endif /* __EXYNOS_PPMU_H__ */
>