Re: [PATCH v3 05/17] drm/msm/dpu: Use OPP API to set clk/perf state

Rajendra Nayak
2020-04-29T14:16:56Z

On 4/29/2020 5:44 AM, Matthias Kaehlcke wrote:
> On Tue, Apr 28, 2020 at 07:02:53PM +0530, Rajendra Nayak wrote:
>> On some qualcomm platforms DPU needs to express a perforamnce state
>> requirement on a power domain depennding on the clock rates.
>> Use OPP table from DT to register with OPP framework and use
>> dev_pm_opp_set_rate() to set the clk/perf state.
>>
>> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
>> Cc: Rob Clark <robdclark@gmail.com>
>> Cc: Sean Paul <sean@poorly.run>
>> Cc: dri-devel@lists.freedesktop.org
>> ---
>> drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c | 3 ++-
>> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 25 ++++++++++++++++++++++++-
>> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h | 4 ++++
>> 3 files changed, 30 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
>> index 11f2beb..fe5717df 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
>> @@ -7,6 +7,7 @@
>> #include <linux/debugfs.h>
>> #include <linux/errno.h>
>> #include <linux/mutex.h>
>> +#include <linux/pm_opp.h>
>> #include <linux/sort.h>
>> #include <linux/clk.h>
>> #include <linux/bitmap.h>
>> @@ -239,7 +240,7 @@ static int _dpu_core_perf_set_core_clk_rate(struct dpu_kms *kms, u64 rate)
>> rate = core_clk->max_rate;
>>
>> core_clk->rate = rate;
>> - return msm_dss_clk_set_rate(core_clk, 1);
>> + return dev_pm_opp_set_rate(&kms->pdev->dev, core_clk->rate);
>> }
>>
>> static u64 _dpu_core_perf_get_core_clk_rate(struct dpu_kms *kms)
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> index ce19f1d..2f53bbf 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
>> @@ -10,6 +10,7 @@
>> #include <linux/debugfs.h>
>> #include <linux/dma-buf.h>
>> #include <linux/of_irq.h>
>> +#include <linux/pm_opp.h>
>>
>> #include <drm/drm_crtc.h>
>> #include <drm/drm_file.h>
>> @@ -1033,11 +1034,23 @@ static int dpu_bind(struct device *dev, struct device *master, void *data)
>> if (!dpu_kms)
>> return -ENOMEM;
>>
>> + dpu_kms->opp_table = dev_pm_opp_set_clkname(dev, "core");
>> + if (IS_ERR(dpu_kms->opp_table))
>> + return PTR_ERR(dpu_kms->opp_table);
>> + /* OPP table is optional */
>> + ret = dev_pm_opp_of_add_table(dev);
>> + if (!ret) {
>> + dpu_kms->has_opp_table = true;
>> + } else if (ret != -ENODEV) {
>> + dev_err(dev, "Invalid OPP table in Device tree\n");
>
> nit: s/Device/device/ ?
>
> uber-nit: s/Invalid/invalid/
>
> most log messages in this file start with a lower case letter, except
> for acronyms/register names
>
> please also change it in the other drivers unless you disagree.

Sure, will do. Thanks.

>
>> + return ret;
>> + }
>> +
>> mp = &dpu_kms->mp;
>> ret = msm_dss_parse_clock(pdev, mp);
>> if (ret) {
>> DPU_ERROR("failed to parse clocks, ret=%d\n", ret);
>> - return ret;
>> + goto err;
>> }
>>
>> platform_set_drvdata(pdev, dpu_kms);
>> @@ -1051,6 +1064,11 @@ static int dpu_bind(struct device *dev, struct device *master, void *data)
>>
>> priv->kms = &dpu_kms->base;
>> return ret;
>> +err:
>> + if (dpu_kms->has_opp_table)
>> + dev_pm_opp_of_remove_table(dev);
>> + dev_pm_opp_put_clkname(dpu_kms->opp_table);
>> + return ret;
>> }
>>
>> static void dpu_unbind(struct device *dev, struct device *master, void *data)
>> @@ -1059,6 +1077,9 @@ static void dpu_unbind(struct device *dev, struct device *master, void *data)
>> struct dpu_kms *dpu_kms = platform_get_drvdata(pdev);
>> struct dss_module_power *mp = &dpu_kms->mp;
>>
>> + if (dpu_kms->has_opp_table)
>> + dev_pm_opp_of_remove_table(dev);
>> + dev_pm_opp_put_clkname(dpu_kms->opp_table);
>> msm_dss_put_clk(mp->clk_config, mp->num_clk);
>> devm_kfree(&pdev->dev, mp->clk_config);
>> mp->num_clk = 0;
>> @@ -1090,6 +1111,8 @@ static int __maybe_unused dpu_runtime_suspend(struct device *dev)
>> struct dpu_kms *dpu_kms = platform_get_drvdata(pdev);
>> struct dss_module_power *mp = &dpu_kms->mp;
>>
>> + /* Drop the performance state vote */
>> + dev_pm_opp_set_rate(dev, 0);
>> rc = msm_dss_enable_clk(mp->clk_config, mp->num_clk, false);
>> if (rc)
>> DPU_ERROR("clock disable failed rc:%d\n", rc);
>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
>> index 211f5de9..2a52e4e 100644
>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.h
>> @@ -128,6 +128,10 @@ struct dpu_kms {
>>
>> struct platform_device *pdev;
>> bool rpm_enabled;
>> +
>> + struct opp_table *opp_table;
>> + bool has_opp_table;
>> +
>> struct dss_module_power mp;
>>
>> /* reference count bandwidth requests, so we know when we can
>
> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>