diff options
author | Michael Forney <mforney@mforney.org> | 2022-03-02 10:26:36 +0000 |
---|---|---|
committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2022-03-02 10:26:36 +0000 |
commit | a00957efee9643c3b025b9d20d6ab4fc6536eb89 (patch) | |
tree | e3bc39463924bcef98b5ca694f655f734aa6e9ad /sys/src/cmd/aux/vga | |
parent | 79c7e4514d90b4d8584c7e3be8a05f89b538c7b7 (diff) |
igfx: maintain single/double-channel LVDS mode from BIOS
Diffstat (limited to 'sys/src/cmd/aux/vga')
-rw-r--r-- | sys/src/cmd/aux/vga/igfx.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/sys/src/cmd/aux/vga/igfx.c b/sys/src/cmd/aux/vga/igfx.c index 58919bea4..bacfb493c 100644 --- a/sys/src/cmd/aux/vga/igfx.c +++ b/sys/src/cmd/aux/vga/igfx.c @@ -850,7 +850,12 @@ initdpll(Igfx *igfx, int x, int freq, int port) dpll->ctrl.v &= ~(3<<24); if(port == PortLCD){ p2 = 14; - if(freq > 112*MHz){ + /* + * Use dual-channel LVDS if the display clock is + * outside the range of single-channel, or it was + * preconfigured by the BIOS. + */ + if(freq > 112*MHz || (igfx->lvds.v>>4 & 3) == 3){ p2 >>= 1; dpll->ctrl.v |= (1<<24); } |