From 2776326457562f971b7b38f4683e298e55252ccc Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Fri, 12 Jul 2019 10:43:25 +0100 Subject: [PATCH] drm/i915/gtt: Compute the radix for gen8 page table levels The radix levels of each page directory are easily determined so replace the numerous hardcoded constants with precomputed derived constants. Signed-off-by: Chris Wilson Reviewed-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20190712094327.24437-4-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_gem_gtt.c | 42 +++++++++++++++++++++++++++++++++++++ drivers/gpu/drm/i915/i915_gem_gtt.h | 1 - 2 files changed, 42 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c index 4544af1..1a60403 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.c +++ b/drivers/gpu/drm/i915/i915_gem_gtt.c @@ -867,6 +867,48 @@ static int gen8_ppgtt_notify_vgt(struct i915_ppgtt *ppgtt, bool create) return 0; } +/* Index shifts into the pagetable are offset by GEN8_PTE_SHIFT [12] */ +#define GEN8_PAGE_SIZE (SZ_4K) /* page and page-directory sizes are the same */ +#define GEN8_PTE_SHIFT (ilog2(GEN8_PAGE_SIZE)) +#define GEN8_PDES (GEN8_PAGE_SIZE / sizeof(u64)) +#define gen8_pd_shift(lvl) ((lvl) * ilog2(GEN8_PDES)) +#define gen8_pd_index(i, lvl) i915_pde_index((i), gen8_pd_shift(lvl)) +#define __gen8_pte_shift(lvl) (GEN8_PTE_SHIFT + gen8_pd_shift(lvl)) +#define __gen8_pte_index(a, lvl) i915_pde_index((a), __gen8_pte_shift(lvl)) + +static inline unsigned int +gen8_pd_range(u64 start, u64 end, int lvl, unsigned int *idx) +{ + const int shift = gen8_pd_shift(lvl); + const u64 mask = ~0ull << gen8_pd_shift(lvl + 1); + + GEM_BUG_ON(start >= end); + end += ~mask >> gen8_pd_shift(1); + + *idx = i915_pde_index(start, shift); + if ((start ^ end) & mask) + return GEN8_PDES - *idx; + else + return i915_pde_index(end, shift) - *idx; +} + +static inline bool gen8_pd_contains(u64 start, u64 end, int lvl) +{ + const u64 mask = ~0ull << gen8_pd_shift(lvl + 1); + + GEM_BUG_ON(start >= end); + return (start ^ end) & mask && (start & ~mask) == 0; +} + +static inline unsigned int gen8_pt_count(u64 start, u64 end) +{ + GEM_BUG_ON(start >= end); + if ((start ^ end) >> gen8_pd_shift(1)) + return GEN8_PDES - (start & (GEN8_PDES - 1)); + else + return end - start; +} + static void gen8_free_page_tables(struct i915_address_space *vm, struct i915_page_directory *pd) { diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h b/drivers/gpu/drm/i915/i915_gem_gtt.h index 36162bb..fb33f25 100644 --- a/drivers/gpu/drm/i915/i915_gem_gtt.h +++ b/drivers/gpu/drm/i915/i915_gem_gtt.h @@ -124,7 +124,6 @@ typedef u64 gen8_pte_t; #define GEN8_3LVL_PDPES 4 #define GEN8_PDE_SHIFT 21 #define GEN8_PDE_MASK 0x1ff -#define GEN8_PTE_SHIFT 12 #define GEN8_PTE_MASK 0x1ff #define GEN8_PTES I915_PTES(sizeof(gen8_pte_t)) -- 2.7.4