From 12c7ea43b930976f35ce75d11fd3f55438868e13 Mon Sep 17 00:00:00 2001 From: Phil Elwell Date: Fri, 4 Aug 2023 11:26:10 +0100 Subject: [PATCH] drm/v3d: Improve MMU support for larger pages The built-in MMU driver went most of the way towards supporting larger kernel pages, but dropped the ball when it comes to calculating indexes into the page table. Fix it. Signed-off-by: Phil Elwell --- drivers/gpu/drm/v3d/v3d_mmu.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) --- a/drivers/gpu/drm/v3d/v3d_mmu.c +++ b/drivers/gpu/drm/v3d/v3d_mmu.c @@ -22,6 +22,7 @@ #include "v3d_regs.h" #define V3D_MMU_PAGE_SHIFT 12 +#define V3D_PAGE_FACTOR (PAGE_SIZE >> V3D_MMU_PAGE_SHIFT) /* Note: All PTEs for the 1MB superpage must be filled with the * superpage bit set. @@ -88,7 +89,7 @@ void v3d_mmu_insert_ptes(struct v3d_bo * { struct drm_gem_shmem_object *shmem_obj = &bo->base; struct v3d_dev *v3d = to_v3d_dev(shmem_obj->base.dev); - u32 page = bo->node.start; + u32 page = bo->node.start * V3D_PAGE_FACTOR; u32 page_prot = V3D_PTE_WRITEABLE | V3D_PTE_VALID; struct sg_dma_page_iter dma_iter; @@ -98,13 +99,13 @@ void v3d_mmu_insert_ptes(struct v3d_bo * u32 pte = page_prot | page_address; u32 i; - BUG_ON(page_address + (PAGE_SIZE >> V3D_MMU_PAGE_SHIFT) >= + BUG_ON(page_address + V3D_PAGE_FACTOR >= BIT(24)); - for (i = 0; i < PAGE_SIZE >> V3D_MMU_PAGE_SHIFT; i++) + for (i = 0; i < V3D_PAGE_FACTOR; i++) v3d->pt[page++] = pte + i; } - WARN_ON_ONCE(page - bo->node.start != + WARN_ON_ONCE(page - (bo->node.start * V3D_PAGE_FACTOR) != shmem_obj->base.size >> V3D_MMU_PAGE_SHIFT); if (v3d_mmu_flush_all(v3d)) @@ -115,10 +116,10 @@ void v3d_mmu_remove_ptes(struct v3d_bo * { struct v3d_dev *v3d = to_v3d_dev(bo->base.base.dev); u32 npages = bo->base.base.size >> V3D_MMU_PAGE_SHIFT; - u32 page; + u32 page = bo->node.start * V3D_PAGE_FACTOR; - for (page = bo->node.start; page < bo->node.start + npages; page++) - v3d->pt[page] = 0; + while (npages--) + v3d->pt[page++] = 0; if (v3d_mmu_flush_all(v3d)) dev_err(v3d->drm.dev, "MMU flush timeout\n");