[PATCH 1/2] Docs/EDID: Fixed erroneous bits of XOFFSET, XPULSE, YOFFSET and YPULSE
From: Christoph Niedermaier
Date: Mon Nov 05 2018 - 03:48:41 EST
The problem was found when EDID data sets for displays other
than the provided samples were generated. The patch has
no effect on the provided samples that still match the data
used in drivers/gpu/drm/drm_edid_load.c.
The provided samples use small values for XOFFSET, XPULSE,
YOFFSET and YPULSE, where the error doesn't occur. This fix
corrects the use of that values in case of high values, because
the most significant bits were treated incorrectly.
So in edid.S msbs4 should use bit 8 and 9 of XOFFSET and XPULS.
For YOFFSET and YPULSE msbs4 should use bit 4 and 5.
lsbs2 was introduced for a better overview, without
functional change.
Removing also the useless value 63 of all files, because
it is added in the *.S description files and then it is
subtracted in edid.S.
Signed-off-by: Christoph Niedermaier <cniedermaier@xxxxxxxxxxxxxxxxx>
Reviewed-by: Carsten Emde <C.Emde@xxxxxxxxx>
---
Documentation/EDID/1024x768.S | 4 ++--
Documentation/EDID/1280x1024.S | 4 ++--
Documentation/EDID/1600x1200.S | 4 ++--
Documentation/EDID/1680x1050.S | 4 ++--
Documentation/EDID/1920x1080.S | 4 ++--
Documentation/EDID/800x600.S | 4 ++--
Documentation/EDID/HOWTO.txt | 4 ++--
Documentation/EDID/edid.S | 10 ++++++----
8 files changed, 20 insertions(+), 18 deletions(-)
diff --git a/Documentation/EDID/1024x768.S b/Documentation/EDID/1024x768.S
index 6f3e4b7..ff4013e 100644
--- a/Documentation/EDID/1024x768.S
+++ b/Documentation/EDID/1024x768.S
@@ -31,8 +31,8 @@
#define YBLANK 38
#define XOFFSET 8
#define XPULSE 144
-#define YOFFSET (63+3)
-#define YPULSE (63+6)
+#define YOFFSET 3
+#define YPULSE 6
#define DPI 72
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux XGA"
diff --git a/Documentation/EDID/1280x1024.S b/Documentation/EDID/1280x1024.S
index bd9bef2a..ce0e85b 100644
--- a/Documentation/EDID/1280x1024.S
+++ b/Documentation/EDID/1280x1024.S
@@ -31,8 +31,8 @@
#define YBLANK 42
#define XOFFSET 48
#define XPULSE 112
-#define YOFFSET (63+1)
-#define YPULSE (63+3)
+#define YOFFSET 1
+#define YPULSE 3
#define DPI 72
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux SXGA"
diff --git a/Documentation/EDID/1600x1200.S b/Documentation/EDID/1600x1200.S
index a45101c..5eeb751 100644
--- a/Documentation/EDID/1600x1200.S
+++ b/Documentation/EDID/1600x1200.S
@@ -31,8 +31,8 @@
#define YBLANK 50
#define XOFFSET 64
#define XPULSE 192
-#define YOFFSET (63+1)
-#define YPULSE (63+3)
+#define YOFFSET 1
+#define YPULSE 3
#define DPI 72
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux UXGA"
diff --git a/Documentation/EDID/1680x1050.S b/Documentation/EDID/1680x1050.S
index b0d7c69..ec67950 100644
--- a/Documentation/EDID/1680x1050.S
+++ b/Documentation/EDID/1680x1050.S
@@ -31,8 +31,8 @@
#define YBLANK 39
#define XOFFSET 104
#define XPULSE 176
-#define YOFFSET (63+3)
-#define YPULSE (63+6)
+#define YOFFSET 3
+#define YPULSE 6
#define DPI 96
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux WSXGA"
diff --git a/Documentation/EDID/1920x1080.S b/Documentation/EDID/1920x1080.S
index 3084355e..e0657af 100644
--- a/Documentation/EDID/1920x1080.S
+++ b/Documentation/EDID/1920x1080.S
@@ -31,8 +31,8 @@
#define YBLANK 45
#define XOFFSET 88
#define XPULSE 44
-#define YOFFSET (63+4)
-#define YPULSE (63+5)
+#define YOFFSET 4
+#define YPULSE 5
#define DPI 96
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux FHD"
diff --git a/Documentation/EDID/800x600.S b/Documentation/EDID/800x600.S
index 6644e26..b6853b2 100644
--- a/Documentation/EDID/800x600.S
+++ b/Documentation/EDID/800x600.S
@@ -28,8 +28,8 @@
#define YBLANK 28
#define XOFFSET 40
#define XPULSE 128
-#define YOFFSET (63+1)
-#define YPULSE (63+4)
+#define YOFFSET 1
+#define YPULSE 4
#define DPI 72
#define VFREQ 60 /* Hz */
#define TIMING_NAME "Linux SVGA"
diff --git a/Documentation/EDID/HOWTO.txt b/Documentation/EDID/HOWTO.txt
index 835db33..7d05a7d 100644
--- a/Documentation/EDID/HOWTO.txt
+++ b/Documentation/EDID/HOWTO.txt
@@ -45,8 +45,8 @@ EDID:
#define YPIX vdisp
#define YBLANK vtotal-vdisp
-#define YOFFSET (63+(vsyncstart-vdisp))
-#define YPULSE (63+(vsyncend-vsyncstart))
+#define YOFFSET vsyncstart-vdisp
+#define YPULSE vsyncend-vsyncstart
The CRC value in the last line
#define CRC 0x55
diff --git a/Documentation/EDID/edid.S b/Documentation/EDID/edid.S
index ef082dc..c3d1381 100644
--- a/Documentation/EDID/edid.S
+++ b/Documentation/EDID/edid.S
@@ -47,9 +47,11 @@
#define mfgname2id(v1,v2,v3) \
((((v1-'@')&0x1f)<<10)+(((v2-'@')&0x1f)<<5)+((v3-'@')&0x1f))
#define swap16(v1) ((v1>>8)+((v1&0xff)<<8))
+#define lsbs2(v1,v2) (((v1&0x0f)<<4)+(v2&0x0f))
#define msbs2(v1,v2) ((((v1>>8)&0x0f)<<4)+((v2>>8)&0x0f))
#define msbs4(v1,v2,v3,v4) \
- (((v1&0x03)>>2)+((v2&0x03)>>4)+((v3&0x03)>>6)+((v4&0x03)>>8))
+ ((((v1>>8)&0x03)<<6)+(((v2>>8)&0x03)<<4)+\
+ (((v3>>4)&0x03)<<2)+((v4>>4)&0x03))
#define pixdpi2mm(pix,dpi) ((pix*25)/dpi)
#define xsize pixdpi2mm(XPIX,DPI)
#define ysize pixdpi2mm(YPIX,DPI)
@@ -200,9 +202,9 @@ y_msbs: .byte msbs2(YPIX,YBLANK)
x_snc_off_lsb: .byte XOFFSET&0xff
/* Horizontal sync pulse width pixels 8 lsbits (0-1023) */
x_snc_pls_lsb: .byte XPULSE&0xff
-/* Bits 7-4 Vertical sync offset lines 4 lsbits -63)
- Bits 3-0 Vertical sync pulse width lines 4 lsbits -63) */
-y_snc_lsb: .byte ((YOFFSET-63)<<4)+(YPULSE-63)
+/* Bits 7-4 Vertical sync offset lines 4 lsbits (0-63)
+ Bits 3-0 Vertical sync pulse width lines 4 lsbits (0-63) */
+y_snc_lsb: .byte lsbs2(YOFFSET, YPULSE)
/* Bits 7-6 Horizontal sync offset pixels 2 msbits
Bits 5-4 Horizontal sync pulse width pixels 2 msbits
Bits 3-2 Vertical sync offset lines 2 msbits
--
2.1.4