On 3/30/2021 7:04 AM, John Stultz wrote:
Commit 7bf168c8fe8c ("drm/msm: Fix speed-bin support not to access outside valid memory"), reworked the nvmem reading of "speed_bin", but in doing so dropped handling of the -ENOENT case which was previously documented as "fine".That change resulted in the db845c board display to fail to start, with the following error: adreno 5000000.gpu: [drm:a6xx_gpu_init] *ERROR* failed to read speed-bin (-2). Some OPPs may not be supported by hardware Thus, this patch simply re-adds the ENOENT handling so the lack of the speed_bin entry isn't fatal for display, and gets things working on db845c. Cc: Rob Clark <robdcl...@gmail.com> Cc: Sean Paul <s...@poorly.run> Cc: Jordan Crouse <jcro...@codeaurora.org> Cc: Eric Anholt <e...@anholt.net> Cc: Douglas Anderson <diand...@chromium.org> Cc: linux-arm-...@vger.kernel.org Cc: freedr...@lists.freedesktop.org Cc: Bjorn Andersson <bjorn.anders...@linaro.org> Cc: YongQin Liu <yongqin....@linaro.org> Reported-by: YongQin Liu <yongqin....@linaro.org> Fixes: 7bf168c8fe8c ("drm/msm: Fix speed-bin support not to access outside valid memory") Signed-off-by: John Stultz <john.stu...@linaro.org> --- drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c index 690409ca8a186..cb2df8736ca85 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c @@ -1406,7 +1406,13 @@ static int a6xx_set_supported_hw(struct device *dev, struct a6xx_gpu *a6xx_gpu, int ret;ret = nvmem_cell_read_u16(dev, "speed_bin", &speedbin);- if (ret) { + /* + * -ENOENT means that the platform doesn't support speedbin which is + * fine + */ + if (ret == -ENOENT) { + return 0; + } else if (ret) { DRM_DEV_ERROR(dev, "failed to read speed-bin (%d). Some OPPs may not be supported by hardware", ret);
Reviewed-by: Akhil P Oommen <akhi...@codeaurora.org> This looks "fine" to me. ;) -Akhil.
