[Intel-gfx] [PATCH 17/29] drm/i915: Make the high dword offset more explicit in i915_reg_read_ioctl

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Store the upper dword of the register offset in the whitelist as well.
This would allow it to read register where the two halves aren't sitting
right next to each other, and it'll make it easier to make register
access type safe.

While at it change the register offsets to u32 from u64. Our register
space isn't quite that big, yet :)

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h     |  1 +
 drivers/gpu/drm/i915/intel_uncore.c | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 0510ca1..7cea51d 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1567,6 +1567,7 @@ enum skl_disp_power_wells {
 #define RING_IMR(base)		((base)+0xa8)
 #define RING_HWSTAM(base)	((base)+0x98)
 #define RING_TIMESTAMP(base)	((base)+0x358)
+#define RING_TIMESTAMP_HI(base)	((base)+0x358 + 4)
 #define   TAIL_ADDR		0x001FFFF8
 #define   HEAD_WRAP_COUNT	0xFFE00000
 #define   HEAD_WRAP_ONE		0x00200000
diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
index f0f97b2..ced494a 100644
--- a/drivers/gpu/drm/i915/intel_uncore.c
+++ b/drivers/gpu/drm/i915/intel_uncore.c
@@ -1261,12 +1261,13 @@ void intel_uncore_fini(struct drm_device *dev)
 #define GEN_RANGE(l, h) GENMASK(h, l)
 
 static const struct register_whitelist {
-	uint64_t offset;
+	uint32_t offset, offset_hi;
 	uint32_t size;
 	/* supported gens, 0x10 for 4, 0x30 for 4 and 5, etc. */
 	uint32_t gen_bitmask;
 } whitelist[] = {
-	{ RING_TIMESTAMP(RENDER_RING_BASE), 8, GEN_RANGE(4, 9) },
+	{ .offset = RING_TIMESTAMP(RENDER_RING_BASE), .offset_hi = RING_TIMESTAMP_HI(RENDER_RING_BASE),
+	  .size = 8, .gen_bitmask = GEN_RANGE(4, 9) },
 };
 
 int i915_reg_read_ioctl(struct drm_device *dev,
@@ -1276,7 +1277,7 @@ int i915_reg_read_ioctl(struct drm_device *dev,
 	struct drm_i915_reg_read *reg = data;
 	struct register_whitelist const *entry = whitelist;
 	unsigned size;
-	u64 offset;
+	uint32_t offset, offset_hi;
 	int i, ret = 0;
 
 	for (i = 0; i < ARRAY_SIZE(whitelist); i++, entry++) {
@@ -1293,6 +1294,7 @@ int i915_reg_read_ioctl(struct drm_device *dev,
 	 * limit the available flags for that register).
 	 */
 	offset = entry->offset;
+	offset_hi = entry->offset_hi;
 	size = entry->size;
 	size |= reg->offset ^ offset;
 
@@ -1300,7 +1302,7 @@ int i915_reg_read_ioctl(struct drm_device *dev,
 
 	switch (size) {
 	case 8 | 1:
-		reg->val = I915_READ64_2x32(offset, offset+4);
+		reg->val = I915_READ64_2x32(offset, offset_hi);
 		break;
 	case 8:
 		reg->val = I915_READ64(offset);
-- 
2.4.10