From: Alex Hung <alex.hung@amd.com>
To: <igt-dev@lists.freedesktop.org>
Cc: brian.starkey@arm.com, maxime@cerno.tech
Subject: [igt-dev] [PATCH 1/3] lib/igt_fb: use the entire 32 bit for fnv1a_crc
Date: Wed, 16 Aug 2023 14:53:14 -0600 [thread overview]
Message-ID: <20230816205316.867195-1-alex.hung@amd.com> (raw)
The function was implemented as a 32-bit hashing function. Commit
85f4c1005150 ("lib/igt_fb: Ignore the X component when computing CRC")
broke this behavior by hashing 8-bit portions. Restore the 32-bit hasing
behavior while still ignoring the X compoment.
Signed-off-by: Alex Hung <alex.hung@amd.com>
---
lib/igt_fb.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)
diff --git a/lib/igt_fb.c b/lib/igt_fb.c
index 60b0e2669..9beb07049 100644
--- a/lib/igt_fb.c
+++ b/lib/igt_fb.c
@@ -4780,16 +4780,11 @@ int igt_fb_get_fnv1a_crc(struct igt_fb *fb, igt_crc_t *crc)
igt_memcpy_from_wc(line, ptr, fb->width * cpp);
for (x = 0; x < fb->width; x++) {
- unsigned int i;
uint32_t pixel = le32_to_cpu(line[x]);
pixel &= 0x00ffffff;
- for (i = 0; i < sizeof(pixel); i++) {
- uint8_t component = (pixel >> (i * 8)) & 0xff;
-
- hash ^= component;
- hash *= FNV1a_PRIME;
- }
+ hash ^= pixel;
+ hash *= FNV1a_PRIME;
}
}
--
2.34.1
next reply other threads:[~2023-08-16 20:53 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-16 20:53 Alex Hung [this message]
2023-08-16 20:53 ` [igt-dev] [PATCH 2/3] lib/igt_fb: add 10 bits (XRGB2101010) supports in fnv1a_crc Alex Hung
2023-08-16 20:53 ` [igt-dev] [PATCH 3/3] tests/kms_writeback: support DRM_FORMAT_XRGB2101010 for writeback Alex Hung
2023-08-17 6:32 ` Maxime Ripard
2023-08-17 7:09 ` Alex Hung
2023-08-17 7:50 ` Maxime Ripard
2023-08-17 14:15 ` Harry Wentland
2023-08-17 16:22 ` Alex Hung
2023-08-22 14:14 ` Maxime Ripard
2023-08-22 14:34 ` Harry Wentland
2023-08-22 13:26 ` Maxime Ripard
2023-08-22 14:51 ` Harry Wentland
2023-08-16 23:41 ` [igt-dev] ○ CI.xeBAT: info for series starting with [1/3] lib/igt_fb: use the entire 32 bit for fnv1a_crc Patchwork
2023-08-16 23:47 ` [igt-dev] ✓ Fi.CI.BAT: success " Patchwork
2023-08-17 11:13 ` [igt-dev] ✓ Fi.CI.IGT: " Patchwork
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