[PATCH v2] drm/msm: handle for EPROBE_DEFER for of_icc_get

[Rob Clark]

On Fri, Jul 10, 2020 at 4:11 PM Jonathan Marek <jonathan at marek.ca> wrote:
>
> On 7/9/20 11:15 AM, Rob Clark wrote:
> > On Thu, Jul 9, 2020 at 7:35 AM Jonathan Marek <jonathan at marek.ca> wrote:
> >>
> >> Check for errors instead of silently not using icc if the msm driver
> >> probes before the interconnect driver.
> >>
> >> Allow ENODATA for ocmem path, as it is optional and this error
> >> is returned when "gfx-mem" path is provided but not "ocmem".
> >>
> >> Remove the WARN_ON in msm_gpu_cleanup because INIT_LIST_HEAD won't have
> >> been called on the list yet when going through the defer error path.
> >>
> >> Changes in v2:
> >> * Changed to not only check for EPROBE_DEFER
> >>
> >> Signed-off-by: Jonathan Marek <jonathan at marek.ca>
> >> ---
> >>   drivers/gpu/drm/msm/adreno/adreno_gpu.c | 17 ++++++++++++++---
> >>   drivers/gpu/drm/msm/msm_gpu.c           |  2 --
> >>   2 files changed, 14 insertions(+), 5 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> >> index 89673c7ed473..0f5217202eb5 100644
> >> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> >> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
> >> @@ -940,12 +940,20 @@ static int adreno_get_pwrlevels(struct device *dev,
> >>                   */
> >>                  gpu->icc_path = of_icc_get(dev, NULL);
> >>          }
> >> -       if (IS_ERR(gpu->icc_path))
> >> +       if (IS_ERR(gpu->icc_path)) {
> >> +               ret = PTR_ERR(gpu->icc_path);
> >>                  gpu->icc_path = NULL;
> >> +               return ret;
> >> +       }
> >>
> >>          gpu->ocmem_icc_path = of_icc_get(dev, "ocmem");
> >> -       if (IS_ERR(gpu->ocmem_icc_path))
> >> +       if (IS_ERR(gpu->ocmem_icc_path)) {
> >> +               ret = PTR_ERR(gpu->ocmem_icc_path);
> >>                  gpu->ocmem_icc_path = NULL;
> >> +               /* allow -ENODATA, ocmem icc is optional */
> >> +               if (ret != -ENODATA)
> >> +                       return ret;
> >> +       }
> >>
> >>          return 0;
> >>   }
> >> @@ -996,6 +1004,7 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
> >>          struct adreno_platform_config *config = pdev->dev.platform_data;
> >>          struct msm_gpu_config adreno_gpu_config  = { 0 };
> >>          struct msm_gpu *gpu = &adreno_gpu->base;
> >> +       int ret;
> >>
> >>          adreno_gpu->funcs = funcs;
> >>          adreno_gpu->info = adreno_info(config->rev);
> >> @@ -1007,7 +1016,9 @@ int adreno_gpu_init(struct drm_device *drm, struct platform_device *pdev,
> >>
> >>          adreno_gpu_config.nr_rings = nr_rings;
> >>
> >> -       adreno_get_pwrlevels(&pdev->dev, gpu);
> >> +       ret = adreno_get_pwrlevels(&pdev->dev, gpu);
> >> +       if (ret)
> >> +               return ret;
> >>
> >>          pm_runtime_set_autosuspend_delay(&pdev->dev,
> >>                  adreno_gpu->info->inactive_period);
> >> diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
> >> index a22d30622306..ccf9a0dd9706 100644
> >> --- a/drivers/gpu/drm/msm/msm_gpu.c
> >> +++ b/drivers/gpu/drm/msm/msm_gpu.c
> >> @@ -959,8 +959,6 @@ void msm_gpu_cleanup(struct msm_gpu *gpu)
> >>
> >>          DBG("%s", gpu->name);
> >>
> >> -       WARN_ON(!list_empty(&gpu->active_list));
> >> -
> >
> > hmm, not a huge fan of removing the WARN_ON().. can we just init the
> > list head earlier?
> >
>
> There doesn't seem to be a nice way of doing that. Would it be
> reasonable to instead detect that msm_gpu_init wasn't called (checking
> if gpu->dev is NULL?), and just skip the msm_gpu_cleanup() call in
> adreno_gpu_cleanup() in that case?

Hmm, you can't just call msm_gpu_init() before looking up the icc path
in adreno_gpu_init()?

BR,
-R

>
> > BR,
> > -R
> >
> >>          for (i = 0; i < ARRAY_SIZE(gpu->rb); i++) {
> >>                  msm_ringbuffer_destroy(gpu->rb[i]);
> >>                  gpu->rb[i] = NULL;
> >> --
> >> 2.26.1
> >>