drm/i915: cleanup the region class/instance encoding

Get rid of the strange REGION_MAP encoding stuff and just use an
explicit class/instance pair for each region. This better matches our
future uAPI where all queryable regions are identified with a u16 class
and u16 instance.

v2: fix whitespace

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210205102026.806699-1-matthew.auld@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Author: matt-auld

drivers/gpu/drm/i915/intel_memory_region.c

@@ -6,14 +6,22 @@
 #include "intel_memory_region.h"
 #include "i915_drv.h"
 
-/* XXX: Hysterical raisins. BIT(inst) needs to just be (inst) at some point. */
-#define REGION_MAP(type, inst) \
-	BIT((type) + INTEL_MEMORY_TYPE_SHIFT) | BIT(inst)
-
-static const u32 intel_region_map[] = {
-	[INTEL_REGION_SMEM] = REGION_MAP(INTEL_MEMORY_SYSTEM, 0),
-	[INTEL_REGION_LMEM] = REGION_MAP(INTEL_MEMORY_LOCAL, 0),
-	[INTEL_REGION_STOLEN] = REGION_MAP(INTEL_MEMORY_STOLEN, 0),
+static const struct {
+	u16 class;
+	u16 instance;
+} intel_region_map[] = {
+	[INTEL_REGION_SMEM] = {
+		.class = INTEL_MEMORY_SYSTEM,
+		.instance = 0,
+	},
+	[INTEL_REGION_LMEM] = {
+		.class = INTEL_MEMORY_LOCAL,
+		.instance = 0,
+	},
+	[INTEL_REGION_STOLEN] = {
+		.class = INTEL_MEMORY_STOLEN,
+		.instance = 0,
+	},
 };
 
 struct intel_memory_region *
@@ -259,12 +267,13 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
 
 	for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) {
 		struct intel_memory_region *mem = ERR_PTR(-ENODEV);
-		u32 type;
+		u16 type, instance;
 
 		if (!HAS_REGION(i915, BIT(i)))
 			continue;
 
-		type = MEMORY_TYPE_FROM_REGION(intel_region_map[i]);
+		type = intel_region_map[i].class;
+		instance = intel_region_map[i].instance;
 		switch (type) {
 		case INTEL_MEMORY_SYSTEM:
 			mem = i915_gem_shmem_setup(i915);
@@ -284,9 +293,9 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915)
 			goto out_cleanup;
 		}
 
-		mem->id = intel_region_map[i];
+		mem->id = i;
 		mem->type = type;
-		mem->instance = MEMORY_INSTANCE_FROM_REGION(intel_region_map[i]);
+		mem->instance = instance;
 
 		i915->mm.regions[i] = mem;
 	}

drivers/gpu/drm/i915/intel_memory_region.h

@@ -39,11 +39,6 @@ enum intel_region_id {
 #define REGION_LMEM     BIT(INTEL_REGION_LMEM)
 #define REGION_STOLEN   BIT(INTEL_REGION_STOLEN)
 
-#define INTEL_MEMORY_TYPE_SHIFT 16
-
-#define MEMORY_TYPE_FROM_REGION(r) (ilog2((r) >> INTEL_MEMORY_TYPE_SHIFT))
-#define MEMORY_INSTANCE_FROM_REGION(r) (ilog2((r) & 0xffff))
-
 #define I915_ALLOC_MIN_PAGE_SIZE  BIT(0)
 #define I915_ALLOC_CONTIGUOUS     BIT(1)
 
@@ -84,9 +79,9 @@ struct intel_memory_region {
 	resource_size_t total;
 	resource_size_t avail;
 
-	unsigned int type;
-	unsigned int instance;
-	unsigned int id;
+	u16 type;
+	u16 instance;
+	enum intel_region_id id;
 	char name[8];
 
 	struct list_head reserved;