drm/i915: Introduce new macros for i915 PTE

Certain functions within i915 uses macros that are defined for
specific architectures by the mmu, such as _PAGE_RW and _PAGE_PRESENT
(Some architectures don't even have these macros defined, like ARM64).

Instead of re-using bits defined for the CPU, we should use bits
defined for i915. This patch introduces two new 64 bit macros,
GEN8_PAGE_PRESENT and GEN8_PAGE_RW, to check for bits 0 and 1 and, to
replace all occurrences of _PAGE_RW and _PAGE_PRESENT within i915.

v2(Michael Cheng): Use GEN8_ instead of I915_
Signed-off-by: Michael Cheng <michael.cheng@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
[ Move defines together with other GEN8 defines ]
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211206215245.513677-2-michael.cheng@intel.com

drivers/gpu/drm/i915/gt/gen8_ppgtt.c

@@ -18,7 +18,7 @@
 static u64 gen8_pde_encode(const dma_addr_t addr,
 			   const enum i915_cache_level level)
 {
-	u64 pde = addr | _PAGE_PRESENT | _PAGE_RW;
+	u64 pde = addr | GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
 
 	if (level != I915_CACHE_NONE)
 		pde |= PPAT_CACHED_PDE;
@@ -32,10 +32,10 @@ static u64 gen8_pte_encode(dma_addr_t addr,
 			   enum i915_cache_level level,
 			   u32 flags)
 {
-	gen8_pte_t pte = addr | _PAGE_PRESENT | _PAGE_RW;
+	gen8_pte_t pte = addr | GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
 
 	if (unlikely(flags & PTE_READ_ONLY))
-		pte &= ~_PAGE_RW;
+		pte &= ~GEN8_PAGE_RW;
 
 	if (flags & PTE_LM)
 		pte |= GEN12_PPGTT_PTE_LM;

drivers/gpu/drm/i915/gt/intel_ggtt.c

@@ -192,7 +192,7 @@ u64 gen8_ggtt_pte_encode(dma_addr_t addr,
 			 enum i915_cache_level level,
 			 u32 flags)
 {
-	gen8_pte_t pte = addr | _PAGE_PRESENT;
+	gen8_pte_t pte = addr | GEN8_PAGE_PRESENT;
 
 	if (flags & PTE_LM)
 		pte |= GEN12_GGTT_PTE_LM;

drivers/gpu/drm/i915/gt/intel_gtt.h

@@ -135,6 +135,9 @@ typedef u64 gen8_pte_t;
 #define GEN8_PPAT_ELLC_OVERRIDE		(0<<2)
 #define GEN8_PPAT(i, x)			((u64)(x) << ((i) * 8))
 
+#define GEN8_PAGE_PRESENT		BIT_ULL(0)
+#define GEN8_PAGE_RW			BIT_ULL(1)
+
 #define GEN8_PDE_IPS_64K BIT(11)
 #define GEN8_PDE_PS_2M   BIT(7)
 

drivers/gpu/drm/i915/gvt/gtt.c

@@ -446,17 +446,17 @@ static bool gen8_gtt_test_present(struct intel_gvt_gtt_entry *e)
 			|| e->type == GTT_TYPE_PPGTT_ROOT_L4_ENTRY)
 		return (e->val64 != 0);
 	else
-		return (e->val64 & _PAGE_PRESENT);
+		return (e->val64 & GEN8_PAGE_PRESENT);
 }
 
 static void gtt_entry_clear_present(struct intel_gvt_gtt_entry *e)
 {
-	e->val64 &= ~_PAGE_PRESENT;
+	e->val64 &= ~GEN8_PAGE_PRESENT;
 }
 
 static void gtt_entry_set_present(struct intel_gvt_gtt_entry *e)
 {
-	e->val64 |= _PAGE_PRESENT;
+	e->val64 |= GEN8_PAGE_PRESENT;
 }
 
 static bool gen8_gtt_test_64k_splited(struct intel_gvt_gtt_entry *e)
@@ -2439,7 +2439,7 @@ static int alloc_scratch_pages(struct intel_vgpu *vgpu,
 		/* The entry parameters like present/writeable/cache type
 		 * set to the same as i915's scratch page tree.
 		 */
-		se.val64 |= _PAGE_PRESENT | _PAGE_RW;
+		se.val64 |= GEN8_PAGE_PRESENT | GEN8_PAGE_RW;
 		if (type == GTT_TYPE_PPGTT_PDE_PT)
 			se.val64 |= PPAT_CACHED;
 
@@ -2896,7 +2896,7 @@ void intel_gvt_restore_ggtt(struct intel_gvt *gvt)
 		offset = vgpu_aperture_gmadr_base(vgpu) >> PAGE_SHIFT;
 		for (idx = 0; idx < num_low; idx++) {
 			pte = mm->ggtt_mm.host_ggtt_aperture[idx];
-			if (pte & _PAGE_PRESENT)
+			if (pte & GEN8_PAGE_PRESENT)
 				write_pte64(vgpu->gvt->gt->ggtt, offset + idx, pte);
 		}
 
@@ -2904,7 +2904,7 @@ void intel_gvt_restore_ggtt(struct intel_gvt *gvt)
 		offset = vgpu_hidden_gmadr_base(vgpu) >> PAGE_SHIFT;
 		for (idx = 0; idx < num_hi; idx++) {
 			pte = mm->ggtt_mm.host_ggtt_hidden[idx];
-			if (pte & _PAGE_PRESENT)
+			if (pte & GEN8_PAGE_PRESENT)
 				write_pte64(vgpu->gvt->gt->ggtt, offset + idx, pte);
 		}
 	}