Code parsing the fields of the NVIDIA block-linear
format modifiers frequently needs to use magic
values defined within the
DRM_FORMAT_MOD_NVIDIA_BLOCK_LINEAR_2D() macro and
document in the comment above it. Such code is
error prone and hard to read. See for example,
nouveau_decode_mod() in the nouveau driver.
This change adds macros defining the mask and
bit shift associated with each parameteric field
in these modifiers.
Signed-off-by: James Jones <jajo...@nvidia.com>
---
include/uapi/drm/drm_fourcc.h | 38 ++++++++++++++++++++++++++---------
1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/include/uapi/drm/drm_fourcc.h b/include/uapi/drm/drm_fourcc.h
index 6483f76a2165..4240a4a146b6 100644
--- a/include/uapi/drm/drm_fourcc.h
+++ b/include/uapi/drm/drm_fourcc.h
@@ -902,6 +902,18 @@ extern "C" {
*/
#define DRM_FORMAT_MOD_NVIDIA_TEGRA_TILED fourcc_mod_code(NVIDIA, 1)
+/* Fields in the parameteric NVIDIA block linear format modifiers */
+#define __fourcc_mod_nvidia_l2gpbh_mask 0xfULL
+#define __fourcc_mod_nvidia_l2gpbh_shift 0
+#define __fourcc_mod_nvidia_pkind_mask 0xffULL
+#define __fourcc_mod_nvidia_pkind_shift 12
+#define __fourcc_mod_nvidia_kgen_mask 0x3ULL
+#define __fourcc_mod_nvidia_kgen_shift 20
+#define __fourcc_mod_nvidia_slayout_mask 0x1ULL
+#define __fourcc_mod_nvidia_slayout_shift 22
+#define __fourcc_mod_nvidia_comp_mask 0x7ULL
+#define __fourcc_mod_nvidia_comp_shift 23
+
/*
* Generalized Block Linear layout, used by desktop GPUs starting with
NV50/G80,
* and Tegra GPUs starting with Tegra K1.
@@ -983,15 +995,21 @@ extern "C" {
* 6 = Reserved for future use
* 7 = Reserved for future use
*
- * 55:25 - Reserved for future use. Must be zero.
+ * 55:26 - Reserved for future use. Must be zero.
*/
#define DRM_FORMAT_MOD_NVIDIA_BLOCK_LINEAR_2D(c, s, g, k, h) \
- fourcc_mod_code(NVIDIA, (0x10 | \
- ((h) & 0xf) | \
- (((k) & 0xff) << 12) | \
- (((g) & 0x3) << 20) | \
- (((s) & 0x1) << 22) | \
- (((c) & 0x7) << 23)))
+ fourcc_mod_code(NVIDIA, \
+ (0x10 | \
+ (((h) & __fourcc_mod_nvidia_l2gpbh_mask) << \
+ __fourcc_mod_nvidia_l2gpbh_shift) | \
+ (((k) & __fourcc_mod_nvidia_pkind_mask) << \
+ __fourcc_mod_nvidia_pkind_shift) | \
+ (((g) & __fourcc_mod_nvidia_kgen_mask) << \
+ __fourcc_mod_nvidia_kgen_shift) | \
+ (((s) & __fourcc_mod_nvidia_slayout_mask) << \
+ __fourcc_mod_nvidia_slayout_shift) | \
+ (((c) & __fourcc_mod_nvidia_comp_mask) << \
+ __fourcc_mod_nvidia_comp_shift)))
/* To grandfather in prior block linear format modifiers to the above layout,
* the page kind "0", which corresponds to "pitch/linear" and hence is unusable
@@ -1002,10 +1020,12 @@ extern "C" {
static inline __u64
drm_fourcc_canonicalize_nvidia_format_mod(__u64 modifier)
{
- if (!(modifier & 0x10) || (modifier & (0xff << 12)))
+ if (!(modifier & 0x10) ||
+ (modifier & (__fourcc_mod_nvidia_pkind_mask <<
+ __fourcc_mod_nvidia_pkind_shift)))
return modifier;
else
- return modifier | (0xfe << 12);
+ return modifier | (0xfeULL << __fourcc_mod_nvidia_pkind_shift);
}
/*
--
2.49.0
