[Freedreno] [PATCH v1 2/5] drm/msm/dp: incorporate pm_runtime framework into DP driver
Dmitry Baryshkov
dmitry.baryshkov at linaro.org
Tue Jul 25 22:33:57 UTC 2023
On 26/07/2023 01:25, Kuogee Hsieh wrote:
>
> On 7/10/2023 9:22 AM, Kuogee Hsieh wrote:
>>
>> On 7/8/2023 7:52 PM, Bjorn Andersson wrote:
>>> On Fri, Jul 07, 2023 at 04:52:20PM -0700, Kuogee Hsieh wrote:
>>>> Incorporating pm runtime framework into DP driver so that power
>>>> and clock resource handling can be centralized allowing easier
>>>> control of these resources in preparation of registering aux bus
>>>> uring probe.
>>>>
>>>> Signed-off-by: Kuogee Hsieh <quic_khsieh at quicinc.com>
>>>> ---
>>>> drivers/gpu/drm/msm/dp/dp_aux.c | 3 ++
>>>> drivers/gpu/drm/msm/dp/dp_display.c | 75
>>>> +++++++++++++++++++++++++++++--------
>>>> 2 files changed, 63 insertions(+), 15 deletions(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c
>>>> b/drivers/gpu/drm/msm/dp/dp_aux.c
>>>> index 8e3b677..c592064 100644
>>>> --- a/drivers/gpu/drm/msm/dp/dp_aux.c
>>>> +++ b/drivers/gpu/drm/msm/dp/dp_aux.c
>>>> @@ -291,6 +291,7 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux
>>>> *dp_aux,
>>>> return -EINVAL;
>>>> }
>>>> + pm_runtime_get_sync(dp_aux->dev);
>>>> mutex_lock(&aux->mutex);
>>>> if (!aux->initted) {
>>>> ret = -EIO;
>>>> @@ -364,6 +365,8 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux
>>>> *dp_aux,
>>>> exit:
>>>> mutex_unlock(&aux->mutex);
>>>> + pm_runtime_mark_last_busy(dp_aux->dev);
>>>> + pm_runtime_put_autosuspend(dp_aux->dev);
>>>> return ret;
>>>> }
>>>> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c
>>>> b/drivers/gpu/drm/msm/dp/dp_display.c
>>>> index 76f1395..2c5706a 100644
>>>> --- a/drivers/gpu/drm/msm/dp/dp_display.c
>>>> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
>>>> @@ -309,6 +309,10 @@ static int dp_display_bind(struct device *dev,
>>>> struct device *master,
>>>> goto end;
>>>> }
>>>> + pm_runtime_enable(dev);
>>>> + pm_runtime_set_autosuspend_delay(dev, 1000);
>>>> + pm_runtime_use_autosuspend(dev);
>>>> +
>>>> return 0;
>>>> end:
>>>> return rc;
>>>> @@ -320,9 +324,8 @@ static void dp_display_unbind(struct device
>>>> *dev, struct device *master,
>>>> struct dp_display_private *dp = dev_get_dp_display_private(dev);
>>>> struct msm_drm_private *priv = dev_get_drvdata(master);
>>>> - /* disable all HPD interrupts */
>>>> - if (dp->core_initialized)
>>>> - dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_INT_MASK,
>>>> false);
>>>> + pm_runtime_dont_use_autosuspend(dev);
>>>> + pm_runtime_disable(dev);
>>>> kthread_stop(dp->ev_tsk);
>>>> @@ -466,10 +469,12 @@ static void dp_display_host_init(struct
>>>> dp_display_private *dp)
>>>> dp->dp_display.connector_type, dp->core_initialized,
>>>> dp->phy_initialized);
>>>> - dp_power_init(dp->power);
>>>> - dp_ctrl_reset_irq_ctrl(dp->ctrl, true);
>>>> - dp_aux_init(dp->aux);
>>>> - dp->core_initialized = true;
>>>> + if (!dp->core_initialized) {
>>>> + dp_power_init(dp->power);
>>>> + dp_ctrl_reset_irq_ctrl(dp->ctrl, true);
>>>> + dp_aux_init(dp->aux);
>>>> + dp->core_initialized = true;
>>> There are two cases that queries core_initialized, both of those are
>>> done to avoid accessing the DP block without it first being powered up.
>>> With the introduction of runtime PM, it seems reasonable to just power
>>> up the block in those two code paths (and remove the variable).
>>>
>>>> + }
>>>> }
>>>> static void dp_display_host_deinit(struct dp_display_private *dp)
>>>> @@ -478,10 +483,12 @@ static void dp_display_host_deinit(struct
>>>> dp_display_private *dp)
>>>> dp->dp_display.connector_type, dp->core_initialized,
>>>> dp->phy_initialized);
>>>> - dp_ctrl_reset_irq_ctrl(dp->ctrl, false);
>>>> - dp_aux_deinit(dp->aux);
>>>> - dp_power_deinit(dp->power);
>>>> - dp->core_initialized = false;
>>>> + if (dp->core_initialized) {
>>>> + dp_ctrl_reset_irq_ctrl(dp->ctrl, false);
>>>> + dp_aux_deinit(dp->aux);
>>>> + dp_power_deinit(dp->power);
>>>> + dp->core_initialized = false;
>>>> + }
>>>> }
>>>> static int dp_display_usbpd_configure_cb(struct device *dev)
>>>> @@ -1304,6 +1311,39 @@ static int dp_display_remove(struct
>>>> platform_device *pdev)
>>>> dp_display_deinit_sub_modules(dp);
>>>> platform_set_drvdata(pdev, NULL);
>>>> + pm_runtime_put_sync_suspend(&pdev->dev);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int dp_pm_runtime_suspend(struct device *dev)
>>>> +{
>>>> + struct platform_device *pdev = to_platform_device(dev);
>>>> + struct msm_dp *dp_display = platform_get_drvdata(pdev);
>>> platform_get_drvdata() is a wrapper for dev_get_drvdata(&pdev->dev), so
>>> there's no need to resolve the platform_device first...
>>>
>>>> + struct dp_display_private *dp;
>>>> +
>>>> + dp = container_of(dp_display, struct dp_display_private,
>>>> dp_display);
>>>> +
>>>> + dp_display_host_phy_exit(dp);
>>>> + dp_catalog_ctrl_hpd_enable(dp->catalog);
>>>> + dp_display_host_deinit(dp);
>>>> +
>>>> + return 0;
>>>> +}
>>>> +
>>>> +static int dp_pm_runtime_resume(struct device *dev)
>>>> +{
>>>> + struct platform_device *pdev = to_platform_device(dev);
>>>> + struct msm_dp *dp_display = platform_get_drvdata(pdev);
>>>> + struct dp_display_private *dp;
>>>> +
>>>> + dp = container_of(dp_display, struct dp_display_private,
>>>> dp_display);
>>>> +
>>>> + dp_display_host_init(dp);
>>>> + if (dp_display->is_edp) {
>>>> + dp_catalog_ctrl_hpd_enable(dp->catalog);
>>>> + dp_display_host_phy_init(dp);
>>>> + }
>>>> return 0;
>>>> }
>>>> @@ -1409,6 +1449,7 @@ static int dp_pm_suspend(struct device *dev)
>>>> }
>>>> static const struct dev_pm_ops dp_pm_ops = {
>>>> + SET_RUNTIME_PM_OPS(dp_pm_runtime_suspend, dp_pm_runtime_resume,
>>>> NULL)
>>>> .suspend = dp_pm_suspend,
>>>> .resume = dp_pm_resume,
>>>> };
>>>> @@ -1493,10 +1534,6 @@ static int dp_display_get_next_bridge(struct
>>>> msm_dp *dp)
>>>> aux_bus = of_get_child_by_name(dev->of_node, "aux-bus");
>>>> if (aux_bus && dp->is_edp) {
>>>> - dp_display_host_init(dp_priv);
>>>> - dp_catalog_ctrl_hpd_enable(dp_priv->catalog);
>>>> - dp_display_host_phy_init(dp_priv);
>>> I'm probably just missing it, but how do we get here with the host
>>> powered up and the phy initialized?
>>
>> if (!dp->core_initialized) is at dp_display_host_init()
>>
>>>
>>>> -
>>>> /*
>>>> * The code below assumes that the panel will finish probing
>>>> * by the time devm_of_dp_aux_populate_ep_devices() returns.
>>>> @@ -1604,6 +1641,7 @@ void dp_bridge_atomic_enable(struct drm_bridge
>>>> *drm_bridge,
>>>> dp_hpd_plug_handle(dp_display, 0);
>>>> mutex_lock(&dp_display->event_mutex);
>>>> + pm_runtime_get_sync(&dp_display->pdev->dev);
>>>> state = dp_display->hpd_state;
>>>> if (state != ST_DISPLAY_OFF && state != ST_MAINLINK_READY) {
>>>> @@ -1684,6 +1722,8 @@ void dp_bridge_atomic_post_disable(struct
>>>> drm_bridge *drm_bridge,
>>>> }
>>>> drm_dbg_dp(dp->drm_dev, "type=%d Done\n", dp->connector_type);
>>>> +
>>>> + pm_runtime_put_sync(&dp_display->pdev->dev);
>>>> mutex_unlock(&dp_display->event_mutex);
>>>> }
>>>> @@ -1723,6 +1763,8 @@ void dp_bridge_hpd_enable(struct drm_bridge
>>>> *bridge)
>>>> struct dp_display_private *dp = container_of(dp_display,
>>>> struct dp_display_private, dp_display);
>>>> mutex_lock(&dp->event_mutex);
>>>> + pm_runtime_get_sync(&dp->pdev->dev);
>>>> +
>>>> dp_catalog_ctrl_hpd_enable(dp->catalog);
>>>> /* enable HDP interrupts */
>>>> @@ -1744,6 +1786,9 @@ void dp_bridge_hpd_disable(struct drm_bridge
>>>> *bridge)
>>>> dp_catalog_ctrl_hpd_disable(dp->catalog);
>>>> dp_display->internal_hpd = false;
>>>> +
>>>> + pm_runtime_mark_last_busy(&dp->pdev->dev);
>>>> + pm_runtime_put_autosuspend(&dp->pdev->dev);
>>>> mutex_unlock(&dp->event_mutex);
>>>> }
>>> The runtime_get/put in dp_bridge_hpd_enable() and disable matches my
>>> expectations. But in the case that we have an external HPD source, where
>>> will the power be turned on?
>>>
>>> Note that you can test this on your device by routing the HPD GPIO to a
>>> display-connector instance and wiring this to the DP node. In the same
>>> way it's done here:
>>>
>>> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/sa8295p-adp.dts#n28
>
> at sc7280, gpio-47 has function 2 as dp-hot-plug pin. but it does not
> has function for general purpose pin.
It has a 'gpio' function, so that the pin can be used as a generic GPIO
with a dp-connector device.
>
> Just curious, to work with external HPD source,
>
> 1) which DRM_BRIDGE_OP_xxx should be used for bridge->ops?
There is no difference. The drm_bridge_connector will select the bridges
according to the needs. E.g. the dp-connector can provide
DRM_BRIDGE_OP_DETECT / OP_HPD (if the hpd-gpios property is configured).
If it does, it will be selected for detection/HPD handling. If not, the
main dp bridge will handle these operations.
>
> 2) are both .hpd_enable and .hpd_disable have to be populated?
No, they are both optional.
--
With best wishes
Dmitry
More information about the dri-devel
mailing list