> -----Original Message-----
> From: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Sent: Wednesday, October 18, 2023 3:17 PM
> To: linux-rockchip@xxxxxxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> linux-pm@xxxxxxxxxxxxxxx; Heiko Stuebner <heiko@xxxxxxxxx>; Chanwoo Choi
> <chanwoo@xxxxxxxxxx>; Kyungmin Park <kyungmin.park@xxxxxxxxxxx>; MyungJoo
> Ham <myungjoo.ham@xxxxxxxxxxx>; Will Deacon <will@xxxxxxxxxx>; Mark
> Rutland <mark.rutland@xxxxxxx>; kernel@xxxxxxxxxxxxxx; Michael Riesch
> <michael.riesch@xxxxxxxxxxxxxx>; Robin Murphy <robin.murphy@xxxxxxx>;
> Vincent Legoll <vincent.legoll@xxxxxxxxx>; Rob Herring
> <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx>;
> devicetree@xxxxxxxxxxxxxxx; Sebastian Reichel
> <sebastian.reichel@xxxxxxxxxxxxx>; Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>;
> Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>; Chanwoo Choi
> <cw00.choi@xxxxxxxxxxx>
> Subject: [PATCH v8 14/26] PM / devfreq: rockchip-dfi: Prepare for multiple
> users
>
> When adding perf support later the DFI must be enabled when either of
> devfreq-event or perf is active. Prepare for that by adding a usage
> counter for the DFI. Also move enabling and disabling of the clock away
> from the devfreq-event specific functions to which the perf specific part
> won't have access.
>
> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Reviewed-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
> Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> ---
> drivers/devfreq/event/rockchip-dfi.c | 57 +++++++++++++++++++---------
> 1 file changed, 40 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/devfreq/event/rockchip-dfi.c
> b/drivers/devfreq/event/rockchip-dfi.c
> index d56a33d03db4c..7a4f1901314d4 100644
> --- a/drivers/devfreq/event/rockchip-dfi.c
> +++ b/drivers/devfreq/event/rockchip-dfi.c
> @@ -68,14 +68,29 @@ struct rockchip_dfi {
> void __iomem *regs;
> struct regmap *regmap_pmu;
> struct clk *clk;
> + int usecount;
> + struct mutex mutex;
> u32 ddr_type;
> unsigned int channel_mask;
> unsigned int max_channels;
> };
>
> -static void rockchip_dfi_start_hardware_counter(struct rockchip_dfi *dfi)
> +static int rockchip_dfi_enable(struct rockchip_dfi *dfi)
> {
> void __iomem *dfi_regs = dfi->regs;
> + int ret = 0;
> +
> + mutex_lock(&dfi->mutex);
> +
> + dfi->usecount++;
> + if (dfi->usecount > 1)
> + goto out;
> +
> + ret = clk_prepare_enable(dfi->clk);
> + if (ret) {
> + dev_err(&dfi->edev->dev, "failed to enable dfi clk: %d\n",
> ret);
> + goto out;
> + }
>
> /* clear DDRMON_CTRL setting */
> writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_TIMER_CNT_EN |
> DDRMON_CTRL_SOFTWARE_EN | @@ -100,14 +115,30 @@ static void
> rockchip_dfi_start_hardware_counter(struct rockchip_dfi *dfi)
> /* enable count, use software mode */
> writel_relaxed(HIWORD_UPDATE(DDRMON_CTRL_SOFTWARE_EN,
> DDRMON_CTRL_SOFTWARE_EN),
> dfi_regs + DDRMON_CTRL);
> +out:
> + mutex_unlock(&dfi->mutex);
> +
> + return ret;
> }
>
> -static void rockchip_dfi_stop_hardware_counter(struct rockchip_dfi *dfi)
> +static void rockchip_dfi_disable(struct rockchip_dfi *dfi)
> {
> void __iomem *dfi_regs = dfi->regs;
>
> + mutex_lock(&dfi->mutex);
> +
> + dfi->usecount--;
> +
> + WARN_ON_ONCE(dfi->usecount < 0);
> +
> + if (dfi->usecount > 0)
> + goto out;
> +
> writel_relaxed(HIWORD_UPDATE(0, DDRMON_CTRL_SOFTWARE_EN),
> dfi_regs + DDRMON_CTRL);
> + clk_disable_unprepare(dfi->clk);
> +out:
> + mutex_unlock(&dfi->mutex);
> }
>
> static void rockchip_dfi_read_counters(struct rockchip_dfi *dfi, struct
> dmc_count *count) @@ -125,29 +156,20 @@ static void
> rockchip_dfi_read_counters(struct rockchip_dfi *dfi, struct dmc_coun
> }
> }
>
> -static int rockchip_dfi_disable(struct devfreq_event_dev *edev)
> +static int rockchip_dfi_event_disable(struct devfreq_event_dev *edev)
> {
> struct rockchip_dfi *dfi = devfreq_event_get_drvdata(edev);
>
> - rockchip_dfi_stop_hardware_counter(dfi);
> - clk_disable_unprepare(dfi->clk);
> + rockchip_dfi_disable(dfi);
>
> return 0;
> }
>
> -static int rockchip_dfi_enable(struct devfreq_event_dev *edev)
> +static int rockchip_dfi_event_enable(struct devfreq_event_dev *edev)
> {
> struct rockchip_dfi *dfi = devfreq_event_get_drvdata(edev);
> - int ret;
> -
> - ret = clk_prepare_enable(dfi->clk);
> - if (ret) {
> - dev_err(&edev->dev, "failed to enable dfi clk: %d\n", ret);
> - return ret;
> - }
>
> - rockchip_dfi_start_hardware_counter(dfi);
> - return 0;
> + return rockchip_dfi_enable(dfi);
> }
>
> static int rockchip_dfi_set_event(struct devfreq_event_dev *edev) @@ -
> 191,8 +213,8 @@ static int rockchip_dfi_get_event(struct devfreq_event_dev
> *edev, }
>
> static const struct devfreq_event_ops rockchip_dfi_ops = {
> - .disable = rockchip_dfi_disable,
> - .enable = rockchip_dfi_enable,
> + .disable = rockchip_dfi_event_disable,
> + .enable = rockchip_dfi_event_enable,
> .get_event = rockchip_dfi_get_event,
> .set_event = rockchip_dfi_set_event,
> };
> @@ -280,6 +302,7 @@ static int rockchip_dfi_probe(struct platform_device
> *pdev)
> return PTR_ERR(dfi->regmap_pmu);
>
> dfi->dev = dev;
> + mutex_init(&dfi->mutex);
>
> desc = &dfi->desc;
> desc->ops = &rockchip_dfi_ops;
> --
> 2.39.2
Applied it. Thanks
Best Regards,
Chanwoo Choi
