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[2/5] drm: EDID: Fix bit masking of {X,Y}{OFFSET,PULSE}

Message ID 20181113171204.ye4pjspiaygunwwo@xylophone.i.decadent.org.uk (mailing list archive)
State New, archived
Headers show
Series Fixes and additions to EDID generation | expand

Commit Message

Ben Hutchings Nov. 13, 2018, 5:12 p.m. UTC 
Currently we fail to encode any of these fields correctly if they
are large enough to require the top 2 bits.  Thankfully none of
the EDID sources here are affected.

The masking and shifting of the top 2 bits (out of 10 for X, 6 for Y)
is only needed in one place so remove the msbs4() macro.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
---
 Documentation/EDID/edid.S | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/Documentation/EDID/edid.S b/Documentation/EDID/edid.S
index ce4b8b4a20b2..8abbf6c24d88 100644
--- a/Documentation/EDID/edid.S
+++ b/Documentation/EDID/edid.S
@@ -48,8 +48,6 @@ 
 	((((v1-'@')&0x1f)<<10)+(((v2-'@')&0x1f)<<5)+((v3-'@')&0x1f))
 #define swap16(v1) ((v1>>8)+((v1&0xff)<<8))
 #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))
 #define pixdpi2mm(pix,dpi) ((pix*25)/dpi)
 #define xsize pixdpi2mm(XPIX,DPI)
 #define ysize pixdpi2mm(YPIX,DPI)
@@ -202,12 +200,12 @@  x_snc_off_lsb:	.byte	XOFFSET&0xff
 x_snc_pls_lsb:	.byte	XPULSE&0xff
 /* 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	(YOFFSET<<4)+YPULSE
+y_snc_lsb:	.byte	((YOFFSET&0x0f)<<4)+(YPULSE&0x0f)
 /* 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
    Bits 1-0 	Vertical sync pulse width lines 2 msbits */
-xy_snc_msbs:	.byte	msbs4(XOFFSET,XPULSE,YOFFSET,YPULSE)
+xy_snc_msbs:	.byte	(((XOFFSET>>8)&3)<<6)+(((XPULSE>>8)&3)<<4)+(((YOFFSET>>4)&3)<<2)+((YPULSE>>4)&3)
 
 /* Horizontal display size, mm, 8 lsbits (0-4095 mm, 161 in) */
 x_dsp_size:	.byte	xsize&0xff