17.12.2020 21:21, Mikko Perttunen пишет:
> On 12/17/20 8:06 PM, Dmitry Osipenko wrote:
>> Add suspend/resume and generic power domain support to the Host1x driver.
>> This is required for enabling system-wide DVFS and supporting dynamic
>> power management using a generic power domain.
>>
>> Tested-by: Peter Geis <pgwipeout@xxxxxxxxx>
>> Tested-by: Nicolas Chauvet <kwizart@xxxxxxxxx>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>> drivers/gpu/host1x/dev.c | 102 ++++++++++++++++++++++++++++++++++-----
>> 1 file changed, 91 insertions(+), 11 deletions(-)
>>
>> diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
>> index d0ebb70e2fdd..c1525cffe7b1 100644
>> --- a/drivers/gpu/host1x/dev.c
>> +++ b/drivers/gpu/host1x/dev.c
>> @@ -12,6 +12,7 @@
>> #include <linux/module.h>
>> #include <linux/of_device.h>
>> #include <linux/of.h>
>> +#include <linux/pm_runtime.h>
>> #include <linux/slab.h>
>> #define CREATE_TRACE_POINTS
>> @@ -417,7 +418,7 @@ static int host1x_probe(struct platform_device *pdev)
>> return err;
>> }
>> - host->rst = devm_reset_control_get(&pdev->dev, "host1x");
>> + host->rst = devm_reset_control_get_exclusive_released(&pdev->dev,
>> "host1x");
>> if (IS_ERR(host->rst)) {
>> err = PTR_ERR(host->rst);
>> dev_err(&pdev->dev, "failed to get reset: %d\n", err);
>> @@ -437,16 +438,15 @@ static int host1x_probe(struct platform_device
>> *pdev)
>> goto iommu_exit;
>> }
>> - err = clk_prepare_enable(host->clk);
>> - if (err < 0) {
>> - dev_err(&pdev->dev, "failed to enable clock\n");
>> - goto free_channels;
>> - }
>> + pm_runtime_enable(&pdev->dev);
>> + err = pm_runtime_get_sync(&pdev->dev);
>> + if (err < 0)
>> + goto rpm_disable;
>> err = reset_control_deassert(host->rst);
>> if (err < 0) {
>> dev_err(&pdev->dev, "failed to deassert reset: %d\n", err);
>> - goto unprepare_disable;
>> + goto rpm_disable;
>> }
>> err = host1x_syncpt_init(host);
>> @@ -485,9 +485,10 @@ static int host1x_probe(struct platform_device
>> *pdev)
>> host1x_syncpt_deinit(host);
>> reset_assert:
>> reset_control_assert(host->rst);
>> -unprepare_disable:
>> - clk_disable_unprepare(host->clk);
>> -free_channels:
>> +rpm_disable:
>> + pm_runtime_put(&pdev->dev);
>> + pm_runtime_disable(&pdev->dev);
>> +
>> host1x_channel_list_free(&host->channel_list);
>> iommu_exit:
>> host1x_iommu_exit(host);
>> @@ -504,16 +505,95 @@ static int host1x_remove(struct platform_device
>> *pdev)
>> host1x_intr_deinit(host);
>> host1x_syncpt_deinit(host);
>> reset_control_assert(host->rst);
>> - clk_disable_unprepare(host->clk);
>> + pm_runtime_put(&pdev->dev);
>> + pm_runtime_disable(&pdev->dev);
>> host1x_iommu_exit(host);
>> return 0;
>> }
>> +static int __maybe_unused host1x_runtime_suspend(struct device *dev)
>> +{
>> + struct host1x *host = dev_get_drvdata(dev);
>> +
>> + clk_disable_unprepare(host->clk);
>> + reset_control_release(host->rst);
>> +
>> + return 0;
>> +}
>> +
>> +static int __maybe_unused host1x_runtime_resume(struct device *dev)
>> +{
>> + struct host1x *host = dev_get_drvdata(dev);
>> + int err;
>> +
>> + err = reset_control_acquire(host->rst);
>> + if (err) {
>> + dev_err(dev, "failed to acquire reset: %d\n", err);
>> + return err;
>> + }
>> +
>> + err = clk_prepare_enable(host->clk);
>> + if (err) {
>> + dev_err(dev, "failed to enable clock: %d\n", err);
>> + goto release_reset;
>> + }
>> +
>> + return 0;
>> +
>> +release_reset:
>> + reset_control_release(host->rst);
>> +
>> + return err;
>> +}
>> +
>> +static __maybe_unused int host1x_suspend(struct device *dev)
>> +{
>> + struct host1x *host = dev_get_drvdata(dev);
>> + int err;
>> +
>> + host1x_syncpt_save(host);
>> +
>> + err = pm_runtime_force_suspend(dev);
>> + if (err < 0)
>> + return err;
>> +
>> + return 0;
>> +}
>> +
>> +static __maybe_unused int host1x_resume(struct device *dev)
>> +{
>> + struct host1x *host = dev_get_drvdata(dev);
>> + struct host1x_channel *channel;
>> + unsigned int index;
>> + int err;
>> +
>> + err = pm_runtime_force_resume(dev);
>> + if (err < 0)
>> + return err;
>> +
>> + host1x_syncpt_restore(host);
>
> We also need to execute 'host1x_setup_sid_table' upon resume.
Indeed, thanks. I'll correct it in the next revision.
Perhaps the actual save/restore needs to be moved to the runtime
callbacks. At least I can't remember right now why this wasn't done in
the first place.
