From: Rob Clark robdclark@chromium.org
[ Upstream commit 5c054db54c43a5fcb5cc81012361f5e3fac37637 ]
Otherwise it is not always obvious if a dt or iommu change is causing us to fall back to global pgtable.
Signed-off-by: Rob Clark robdclark@chromium.org Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@linaro.org Patchwork: https://patchwork.freedesktop.org/patch/537359/ Link: https://lore.kernel.org/r/20230516222039.907690-2-robdclark@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/msm_iommu.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c index ecab6287c1c39..b81390d6ebd38 100644 --- a/drivers/gpu/drm/msm/msm_iommu.c +++ b/drivers/gpu/drm/msm/msm_iommu.c @@ -155,7 +155,12 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent) /* Get the pagetable configuration from the domain */ if (adreno_smmu->cookie) ttbr1_cfg = adreno_smmu->get_ttbr1_cfg(adreno_smmu->cookie); - if (!ttbr1_cfg) + + /* + * If you hit this WARN_ONCE() you are probably missing an entry in + * qcom_smmu_impl_of_match[] in arm-smmu-qcom.c + */ + if (WARN_ONCE(!ttbr1_cfg, "No per-process page tables")) return ERR_PTR(-ENODEV);
pagetable = kzalloc(sizeof(*pagetable), GFP_KERNEL);