Merge tag 'drm-msm-fixes-2025-08-26' of https://gitlab.freedesktop.org/drm/msm into drm-fixes

Fixes for v6.17-rc4

Core/GPU:
- fix comment doc warning in gpuvm
- fix build with KMS disabled
- fix pgtable setup/teardown race
- global fault counter fix
- various error path fixes
- GPU devcoredump snapshot fixes
- handle in-place VM_BIND remaps to solve turnip vm update race
- skip re-emitting IBs for unusable VMs
- Don't use %pK through printk
- moved display snapshot init earlier, fixing a crash

DPU:
- Fixed crash in virtual plane checking code
- Fixed mode comparison in virtual plane checking code

DSI:
- Adjusted width of resulution-related registers
- Fixed locking issue on 14nm PLLs

UBWC (per Bjorn's ack)
- Added UBWC configuration for several missing platforms (fixing
  regression)

Signed-off-by: Dave Airlie <[email protected]>
From: Rob Clark <[email protected]>
Link: https://lore.kernel.org/r/CACSVV02+u1VW1dzuz6JWwVEfpgTj6Y-JXMH+vX43KsKTVsW+Yg@mail.gmail.com

1 files changed, 12 insertions, 4 deletions

diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
index 55c29f49b788..76cdd5ea06a0 100644
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -14,7 +14,9 @@
 struct msm_iommu {
 	struct msm_mmu base;
 	struct iommu_domain *domain;
-	atomic_t pagetables;
+
+	struct mutex init_lock;  /* protects pagetables counter and prr_page */
+	int pagetables;
 	struct page *prr_page;
 
 	struct kmem_cache *pt_cache;
@@ -227,7 +229,8 @@ static void msm_iommu_pagetable_destroy(struct msm_mmu *mmu)
 	 * If this is the last attached pagetable for the parent,
 	 * disable TTBR0 in the arm-smmu driver
 	 */
-	if (atomic_dec_return(&iommu->pagetables) == 0) {
+	mutex_lock(&iommu->init_lock);
+	if (--iommu->pagetables == 0) {
 		adreno_smmu->set_ttbr0_cfg(adreno_smmu->cookie, NULL);
 
 		if (adreno_smmu->set_prr_bit) {
@@ -236,6 +239,7 @@ static void msm_iommu_pagetable_destroy(struct msm_mmu *mmu)
 			iommu->prr_page = NULL;
 		}
 	}
+	mutex_unlock(&iommu->init_lock);
 
 	free_io_pgtable_ops(pagetable->pgtbl_ops);
 	kfree(pagetable);
@@ -568,9 +572,12 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent, bool kernel_m
 	 * If this is the first pagetable that we've allocated, send it back to
 	 * the arm-smmu driver as a trigger to set up TTBR0
 	 */
-	if (atomic_inc_return(&iommu->pagetables) == 1) {
+	mutex_lock(&iommu->init_lock);
+	if (iommu->pagetables++ == 0) {
 		ret = adreno_smmu->set_ttbr0_cfg(adreno_smmu->cookie, &ttbr0_cfg);
 		if (ret) {
+			iommu->pagetables--;
+			mutex_unlock(&iommu->init_lock);
 			free_io_pgtable_ops(pagetable->pgtbl_ops);
 			kfree(pagetable);
 			return ERR_PTR(ret);
@@ -595,6 +602,7 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent, bool kernel_m
 			adreno_smmu->set_prr_bit(adreno_smmu->cookie, true);
 		}
 	}
+	mutex_unlock(&iommu->init_lock);
 
 	/* Needed later for TLB flush */
 	pagetable->parent = parent;
@@ -730,7 +738,7 @@ struct msm_mmu *msm_iommu_new(struct device *dev, unsigned long quirks)
 	iommu->domain = domain;
 	msm_mmu_init(&iommu->base, dev, &funcs, MSM_MMU_IOMMU);
 
-	atomic_set(&iommu->pagetables, 0);
+	mutex_init(&iommu->init_lock);
 
 	ret = iommu_attach_device(iommu->domain, dev);
 	if (ret) {