[PATCH 5/7] drm/amdgpu: Fix consecutive DPC recoveries failure.

Alex Deucher alexdeucher at gmail.com
Fri Aug 28 14:32:02 UTC 2020


On Fri, Aug 28, 2020 at 10:21 AM Andrey Grodzovsky
<Andrey.Grodzovsky at amd.com> wrote:
>
>
> On 8/28/20 10:13 AM, Alex Deucher wrote:
> > On Thu, Aug 27, 2020 at 10:54 AM Andrey Grodzovsky
> > <Andrey.Grodzovsky at amd.com> wrote:
> >>
> >> On 8/26/20 11:20 AM, Alex Deucher wrote:
> >>> On Wed, Aug 26, 2020 at 10:46 AM Andrey Grodzovsky
> >>> <andrey.grodzovsky at amd.com> wrote:
> >>>> DPC recovery after prev. DPC recovery or after prev. MODE1 reset fails
> >>>> unles you save the cashe the saved PCI confspace to load it after
> >>>> each new reset.
> >>>> Also use same cached state for other use case of restoring PCI confspace
> >>>> such as GPU mode1 or VGA switheroo.
> >>>>
> >>> We don't want to keep the saved state around in the pci core
> >>> otherwise, the pci core will assume we are managing the saved state
> >>> for suspend and resume.  I think we want logic like this:
> >>>
> >>> At driver load time:
> >>> pci_save_state(pdev);
> >>> adev->pci_state = pci_store_saved_state(pdev);
> >>> pci_restore_state(adev->pdev);
> >>>
> >>> then in the case of dpc, do:
> >>> pci_load_saved_state(pdev, adev->pci_state);
> >>>
> >>> For all the other cases, just leave the code as is.
> >>
> >> Actually, as we already discussed - caching the PCI confspace only once on boot
> >> and not doing it again after each subsequent
> >> controlled or spontaneous reset runs the risk of loading back outdated confspace
> >> settings. I am not sure if and when but, is it indeed
> >> possible we make changes to PCI confspace registers during runtime and so the
> >> cached state from boot might be outdated
> >> to load back ?
> > As Christain noted we may change config space at load time if we
> > resize the BAR.  So we should probably save config space at the end of
> > the driver load init sequence.  This saved state is just a backup in
> > case something kills pci config space without saving it.  I think it's
> > fine to update the cached copy whenever we call pci_save_state(), but
> > what we don't want to do is call pci_save_state() at init time without
> > calling pci_restore_state().  pci_save_state() caches a copy of the
> > save state in the pdev structure.  The pci core uses the presence of
> > this cached state to make decisions about whether the driver or the
> > core should handle a bunch of stuff at suspend/resume.  If the cached
> > state is present, it assumes the driver will be handling all of the
> > pci related state management for power management.  I'd rather keep
> > that in the core.  I think the patch is good, but this part needs to
> > be reworked:
>
>
> In this case I believe the patch should stay as is with the only change at
> adding pci_restore_state(pdev) in amdgpu_device_cache_pci_state after the call
> to pci_store_saved_state - right ?

Correct.

Alex


>
> Andrey
>
>
> >
> > @@ -3401,8 +3401,9 @@ int amdgpu_device_init(struct amdgpu_device *adev,
> >          if (r)
> >                  dev_err(adev->dev, "amdgpu_pmu_init failed\n");
> >
> > -       if (pci_save_state(pdev))
> > -               DRM_ERROR("Failed to save PCI state!!\n");
> > +       /* Have stored pci confspace at hand for restore in sudden PCI error */
> > +       if (!amdgpu_device_cache_pci_state(adev->pdev))
> > +               DRM_WARN("Failed to cache PCI state!");
> >
> > Something like this:
> >
> > @@ -3401,8 +3401,9 @@ int amdgpu_device_init(struct amdgpu_device *adev,
> >          if (r)
> >                  dev_err(adev->dev, "amdgpu_pmu_init failed\n");
> >
> > -       if (pci_save_state(pdev))
> > -               DRM_ERROR("Failed to save PCI state!!\n");
> > +       /* Have stored pci confspace at hand for restore in sudden PCI error */
> > +       if (!amdgpu_device_cache_pci_state(adev->pdev))
> > +               DRM_WARN("Failed to cache PCI state!");
> > +       if (!amdgpu_device_load_pci_state(adev->pdev))
> > +               DRM_WARN("Failed to restore PCI state!");
> >
> > This way we have a cached copy in the driver but not in the pci core.
> >
> >
> > Alex
> >
> >
> >> Andrey
> >>
> >>
> >>> Alex
> >>>
> >>>
> >>>> Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com>
> >>>> ---
> >>>>    drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  6 +++
> >>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 60 +++++++++++++++++++++++++++---
> >>>>    drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c    |  4 +-
> >>>>    drivers/gpu/drm/amd/amdgpu/nv.c            |  4 +-
> >>>>    drivers/gpu/drm/amd/amdgpu/soc15.c         |  4 +-
> >>>>    5 files changed, 66 insertions(+), 12 deletions(-)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> index 3489622..42ee208 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> >>>> @@ -992,7 +992,9 @@ struct amdgpu_device {
> >>>>           atomic_t                        throttling_logging_enabled;
> >>>>           struct ratelimit_state          throttling_logging_rs;
> >>>>           uint32_t                        ras_features;
> >>>> +
> >>> Unrelated whitespace changes.
> >>>
> >>>>           bool                            in_dpc;
> >>>> +       struct pci_saved_state          *pci_state;
> >>>>    };
> >>>>
> >>>>    static inline struct amdgpu_device *drm_to_adev(struct drm_device *ddev)
> >>>> @@ -1272,6 +1274,10 @@ pci_ers_result_t amdgpu_pci_mmio_enabled(struct pci_dev *pdev);
> >>>>    pci_ers_result_t amdgpu_pci_slot_reset(struct pci_dev *pdev);
> >>>>    void amdgpu_pci_resume(struct pci_dev *pdev);
> >>>>
> >>>> +bool amdgpu_device_cache_pci_state(struct pci_dev *pdev);
> >>>> +bool amdgpu_device_load_pci_state(struct pci_dev *pdev);
> >>>> +
> >>>> +
> >>>>
> >>>>    #include "amdgpu_object.h"
> >>>>
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> >>>> index d9e3994..2c088df 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> >>>> @@ -1283,7 +1283,7 @@ static void amdgpu_switcheroo_set_state(struct pci_dev *pdev,
> >>>>                   dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
> >>>>
> >>>>                   pci_set_power_state(dev->pdev, PCI_D0);
> >>>> -               pci_restore_state(dev->pdev);
> >>>> +               amdgpu_device_load_pci_state(dev->pdev);
> >>>>                   r = pci_enable_device(dev->pdev);
> >>>>                   if (r)
> >>>>                           DRM_WARN("pci_enable_device failed (%d)\n", r);
> >>>> @@ -1296,7 +1296,7 @@ static void amdgpu_switcheroo_set_state(struct pci_dev *pdev,
> >>>>                   drm_kms_helper_poll_disable(dev);
> >>>>                   dev->switch_power_state = DRM_SWITCH_POWER_CHANGING;
> >>>>                   amdgpu_device_suspend(dev, true);
> >>>> -               pci_save_state(dev->pdev);
> >>>> +               amdgpu_device_cache_pci_state(dev->pdev);
> >>>>                   /* Shut down the device */
> >>>>                   pci_disable_device(dev->pdev);
> >>>>                   pci_set_power_state(dev->pdev, PCI_D3cold);
> >>>> @@ -3401,8 +3401,9 @@ int amdgpu_device_init(struct amdgpu_device *adev,
> >>>>           if (r)
> >>>>                   dev_err(adev->dev, "amdgpu_pmu_init failed\n");
> >>>>
> >>>> -       if (pci_save_state(pdev))
> >>>> -               DRM_ERROR("Failed to save PCI state!!\n");
> >>>> +       /* Have stored pci confspace at hand for restore in sudden PCI error */
> >>>> +       if (!amdgpu_device_cache_pci_state(adev->pdev))
> >>>> +               DRM_WARN("Failed to cache PCI state!");
> >>>>
> >>>>           return 0;
> >>>>
> >>>> @@ -3430,6 +3431,8 @@ void amdgpu_device_fini(struct amdgpu_device *adev)
> >>>>           flush_delayed_work(&adev->delayed_init_work);
> >>>>           adev->shutdown = true;
> >>>>
> >>>> +       kfree(adev->pci_state);
> >>>> +
> >>>>           /* make sure IB test finished before entering exclusive mode
> >>>>            * to avoid preemption on IB test
> >>>>            * */
> >>>> @@ -4855,7 +4858,7 @@ pci_ers_result_t amdgpu_pci_slot_reset(struct pci_dev *pdev)
> >>>>           /* wait for asic to come out of reset */
> >>>>           msleep(500);
> >>>>
> >>>> -       pci_restore_state(pdev);
> >>>> +       amdgpu_device_load_pci_state(pdev);
> >>>>
> >>>>           /* confirm  ASIC came out of reset */
> >>>>           for (i = 0; i < adev->usec_timeout; i++) {
> >>>> @@ -4934,8 +4937,10 @@ pci_ers_result_t amdgpu_pci_slot_reset(struct pci_dev *pdev)
> >>>>
> >>>>    out:
> >>>>
> >>>> -       if (!r)
> >>>> +       if (!r) {
> >>>> +               amdgpu_device_cache_pci_state(adev->pdev);
> >>>>                   DRM_INFO("PCIe error recovery succeeded\n");
> >>>> +       }
> >>>>           else {
> >>>>                   DRM_ERROR("PCIe error recovery failed, err:%d", r);
> >>>>                   amdgpu_device_unlock_adev(adev);
> >>>> @@ -4974,3 +4979,46 @@ void amdgpu_pci_resume(struct pci_dev *pdev)
> >>>>
> >>>>           amdgpu_device_unlock_adev(adev);
> >>>>    }
> >>>> +
> >>>> +bool amdgpu_device_cache_pci_state(struct pci_dev *pdev)
> >>>> +{
> >>>> +       struct drm_device *dev = pci_get_drvdata(pdev);
> >>>> +       struct amdgpu_device *adev = drm_to_adev(dev);
> >>>> +       int r;
> >>>> +
> >>>> +       r = pci_save_state(pdev);
> >>>> +       if (!r) {
> >>>> +               kfree(adev->pci_state);
> >>>> +
> >>>> +               adev->pci_state = pci_store_saved_state(pdev);
> >>>> +
> >>>> +               if (!adev->pci_state) {
> >>>> +                       DRM_ERROR("Failed to store PCI saved state");
> >>>> +                       return false;
> >>>> +               }
> >>>> +       } else {
> >>>> +               DRM_WARN("Failed to save PCI state, err:%d\n", r);
> >>>> +               return false;
> >>>> +       }
> >>>> +
> >>>> +       return true;
> >>>> +}
> >>>> +
> >>>> +bool amdgpu_device_load_pci_state(struct pci_dev *pdev)
> >>>> +{
> >>>> +       struct drm_device *dev = pci_get_drvdata(pdev);
> >>>> +       struct amdgpu_device *adev = drm_to_adev(dev);
> >>>> +       int r;
> >>>> +
> >>>> +       if (!adev->pci_state)
> >>>> +               return false;
> >>>> +
> >>>> +       r = pci_load_saved_state(pdev, adev->pci_state);
> >>>> +
> >>>> +       if (!r) {
> >>>> +               pci_restore_state(pdev);
> >>>> +       } else {
> >>>> +               DRM_WARN("Failed to load PCI state, err:%d\n", r);
> >>>> +               return false;
> >>>> +       }
> >>>> +}
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> >>>> index 4bbcc70..7a6482a 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> >>>> @@ -1320,7 +1320,7 @@ static int amdgpu_pmops_runtime_suspend(struct device *dev)
> >>>>                   if (amdgpu_is_atpx_hybrid()) {
> >>>>                           pci_ignore_hotplug(pdev);
> >>>>                   } else {
> >>>> -                       pci_save_state(pdev);
> >>>> +                       amdgpu_device_cache_pci_state(pdev);
> >>>>                           pci_disable_device(pdev);
> >>>>                           pci_ignore_hotplug(pdev);
> >>>>                           pci_set_power_state(pdev, PCI_D3cold);
> >>>> @@ -1353,7 +1353,7 @@ static int amdgpu_pmops_runtime_resume(struct device *dev)
> >>>>                           pci_set_master(pdev);
> >>>>                   } else {
> >>>>                           pci_set_power_state(pdev, PCI_D0);
> >>>> -                       pci_restore_state(pdev);
> >>>> +                       amdgpu_device_load_pci_state(pdev);
> >>>>                           ret = pci_enable_device(pdev);
> >>>>                           if (ret)
> >>>>                                   return ret;
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/nv.c b/drivers/gpu/drm/amd/amdgpu/nv.c
> >>>> index 4d14023..0ec6603 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/nv.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/nv.c
> >>>> @@ -311,7 +311,7 @@ static int nv_asic_mode1_reset(struct amdgpu_device *adev)
> >>>>           /* disable BM */
> >>>>           pci_clear_master(adev->pdev);
> >>>>
> >>>> -       pci_save_state(adev->pdev);
> >>>> +       amdgpu_device_cache_pci_state(adev->pdev);
> >>>>
> >>>>           if (amdgpu_dpm_is_mode1_reset_supported(adev)) {
> >>>>                   dev_info(adev->dev, "GPU smu mode1 reset\n");
> >>>> @@ -323,7 +323,7 @@ static int nv_asic_mode1_reset(struct amdgpu_device *adev)
> >>>>
> >>>>           if (ret)
> >>>>                   dev_err(adev->dev, "GPU mode1 reset failed\n");
> >>>> -       pci_restore_state(adev->pdev);
> >>>> +       amdgpu_device_load_pci_state(adev->pdev);
> >>>>
> >>>>           /* wait for asic to come out of reset */
> >>>>           for (i = 0; i < adev->usec_timeout; i++) {
> >>>> diff --git a/drivers/gpu/drm/amd/amdgpu/soc15.c b/drivers/gpu/drm/amd/amdgpu/soc15.c
> >>>> index 2f93c47..ddd55e3 100644
> >>>> --- a/drivers/gpu/drm/amd/amdgpu/soc15.c
> >>>> +++ b/drivers/gpu/drm/amd/amdgpu/soc15.c
> >>>> @@ -484,13 +484,13 @@ static int soc15_asic_mode1_reset(struct amdgpu_device *adev)
> >>>>           /* disable BM */
> >>>>           pci_clear_master(adev->pdev);
> >>>>
> >>>> -       pci_save_state(adev->pdev);
> >>>> +       amdgpu_device_cache_pci_state(adev->pdev);
> >>>>
> >>>>           ret = psp_gpu_reset(adev);
> >>>>           if (ret)
> >>>>                   dev_err(adev->dev, "GPU mode1 reset failed\n");
> >>>>
> >>>> -       pci_restore_state(adev->pdev);
> >>>> +       amdgpu_device_load_pci_state(adev->pdev);
> >>>>
> >>>>           /* wait for asic to come out of reset */
> >>>>           for (i = 0; i < adev->usec_timeout; i++) {
> >>>> --
> >>>> 2.7.4
> >>>>
> >>>> _______________________________________________
> >>>> amd-gfx mailing list
> >>>> amd-gfx at lists.freedesktop.org
> >>>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Famd-gfx&data=02%7C01%7CAndrey.Grodzovsky%40amd.com%7C3d5f35b27c9c4055150908d84b5c81cb%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637342207973407357&sdata=qA1xTpuY1JtOTPf7m1WhpH%2BFqVv8GA5CDMu%2BJa3Ds4o%3D&reserved=0


More information about the amd-gfx mailing list