From 5c054db54c43a5fcb5cc81012361f5e3fac37637 Mon Sep 17 00:00:00 2001
From: Rob Clark <robdclark@chromium.org>
Date: Tue, 16 May 2023 15:20:37 -0700
Subject: [PATCH] drm/msm: Be more shouty if per-process pgtables aren't working
Git-commit: 5c054db54c43a5fcb5cc81012361f5e3fac37637
Patch-mainline: v6.4-rc3
References: git-fixes
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
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/msm/msm_iommu.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -157,7 +157,12 @@ struct msm_mmu *msm_iommu_pagetable_crea
/* 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);
/*