6.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthew Brost matthew.brost@intel.com
[ Upstream commit 6d3581edffea0b3a64b0d3094d3f09222e0024f7 ]
Overmapping the identity VRAM mapping is triggering hardware bugs on certain platforms. Use 2M pages for the last unaligned (to 1G) VRAM chunk.
v2: - Always use 2M pages for last chunk (Fei Yang) - break loop when 2M pages are used - Add assert for usable_size being 2M aligned v3: - Fix checkpatch
Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Fei Yang fei.yang@intel.com Signed-off-by: Matthew Brost matthew.brost@intel.com Reviewed-by: Fei Yang fei.yang@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20240603181824.1927675-1-matth... Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/xe/xe_migrate.c | 55 +++++++++++++++++++++++++-------- 1 file changed, 42 insertions(+), 13 deletions(-)
diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c index 198f5c2189cb..208649436fdb 100644 --- a/drivers/gpu/drm/xe/xe_migrate.c +++ b/drivers/gpu/drm/xe/xe_migrate.c @@ -69,7 +69,7 @@ struct xe_migrate {
#define MAX_PREEMPTDISABLE_TRANSFER SZ_8M /* Around 1ms. */ #define MAX_CCS_LIMITED_TRANSFER SZ_4M /* XE_PAGE_SIZE * (FIELD_MAX(XE2_CCS_SIZE_MASK) + 1) */ -#define NUM_KERNEL_PDE 17 +#define NUM_KERNEL_PDE 15 #define NUM_PT_SLOTS 32 #define LEVEL0_PAGE_TABLE_ENCODE_SIZE SZ_2M #define MAX_NUM_PTE 512 @@ -137,10 +137,11 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m, struct xe_device *xe = tile_to_xe(tile); u16 pat_index = xe->pat.idx[XE_CACHE_WB]; u8 id = tile->id; - u32 num_entries = NUM_PT_SLOTS, num_level = vm->pt_root[id]->level; + u32 num_entries = NUM_PT_SLOTS, num_level = vm->pt_root[id]->level, + num_setup = num_level + 1; u32 map_ofs, level, i; struct xe_bo *bo, *batch = tile->mem.kernel_bb_pool->bo; - u64 entry; + u64 entry, pt30_ofs;
/* Can't bump NUM_PT_SLOTS too high */ BUILD_BUG_ON(NUM_PT_SLOTS > SZ_2M/XE_PAGE_SIZE); @@ -160,10 +161,12 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m, if (IS_ERR(bo)) return PTR_ERR(bo);
- entry = vm->pt_ops->pde_encode_bo(bo, bo->size - XE_PAGE_SIZE, pat_index); + /* PT31 reserved for 2M identity map */ + pt30_ofs = bo->size - 2 * XE_PAGE_SIZE; + entry = vm->pt_ops->pde_encode_bo(bo, pt30_ofs, pat_index); xe_pt_write(xe, &vm->pt_root[id]->bo->vmap, 0, entry);
- map_ofs = (num_entries - num_level) * XE_PAGE_SIZE; + map_ofs = (num_entries - num_setup) * XE_PAGE_SIZE;
/* Map the entire BO in our level 0 pt */ for (i = 0, level = 0; i < num_entries; level++) { @@ -234,7 +237,7 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m, }
/* Write PDE's that point to our BO. */ - for (i = 0; i < num_entries - num_level; i++) { + for (i = 0; i < map_ofs / PAGE_SIZE; i++) { entry = vm->pt_ops->pde_encode_bo(bo, (u64)i * XE_PAGE_SIZE, pat_index);
@@ -252,28 +255,54 @@ static int xe_migrate_prepare_vm(struct xe_tile *tile, struct xe_migrate *m, /* Identity map the entire vram at 256GiB offset */ if (IS_DGFX(xe)) { u64 pos, ofs, flags; + /* XXX: Unclear if this should be usable_size? */ + u64 vram_limit = xe->mem.vram.actual_physical_size + + xe->mem.vram.dpa_base;
level = 2; ofs = map_ofs + XE_PAGE_SIZE * level + 256 * 8; flags = vm->pt_ops->pte_encode_addr(xe, 0, pat_index, level, true, 0);
+ xe_assert(xe, IS_ALIGNED(xe->mem.vram.usable_size, SZ_2M)); + /* - * Use 1GB pages, it shouldn't matter the physical amount of - * vram is less, when we don't access it. + * Use 1GB pages when possible, last chunk always use 2M + * pages as mixing reserved memory (stolen, WOCPM) with a single + * mapping is not allowed on certain platforms. */ - for (pos = xe->mem.vram.dpa_base; - pos < xe->mem.vram.actual_physical_size + xe->mem.vram.dpa_base; - pos += SZ_1G, ofs += 8) + for (pos = xe->mem.vram.dpa_base; pos < vram_limit; + pos += SZ_1G, ofs += 8) { + if (pos + SZ_1G >= vram_limit) { + u64 pt31_ofs = bo->size - XE_PAGE_SIZE; + + entry = vm->pt_ops->pde_encode_bo(bo, pt31_ofs, + pat_index); + xe_map_wr(xe, &bo->vmap, ofs, u64, entry); + + flags = vm->pt_ops->pte_encode_addr(xe, 0, + pat_index, + level - 1, + true, 0); + + for (ofs = pt31_ofs; pos < vram_limit; + pos += SZ_2M, ofs += 8) + xe_map_wr(xe, &bo->vmap, ofs, u64, pos | flags); + break; /* Ensure pos == vram_limit assert correct */ + } + xe_map_wr(xe, &bo->vmap, ofs, u64, pos | flags); + } + + xe_assert(xe, pos == vram_limit); }
/* * Example layout created above, with root level = 3: * [PT0...PT7]: kernel PT's for copy/clear; 64 or 4KiB PTE's * [PT8]: Kernel PT for VM_BIND, 4 KiB PTE's - * [PT9...PT28]: Userspace PT's for VM_BIND, 4 KiB PTE's - * [PT29 = PDE 0] [PT30 = PDE 1] [PT31 = PDE 2] + * [PT9...PT27]: Userspace PT's for VM_BIND, 4 KiB PTE's + * [PT28 = PDE 0] [PT29 = PDE 1] [PT30 = PDE 2] [PT31 = 2M vram identity map] * * This makes the lowest part of the VM point to the pagetables. * Hence the lowest 2M in the vm should point to itself, with a few writes