[Nouveau] [PATCH 1/2] drm/nouveau/bios/therm: handle vbioses with duplicate entries (mostly nva5)

[Martin Peres]

From: Martin Peres <martin.peres at labri.fr>

Some vbioses have extra useless entries after "the end" of the table. This is
problematic since all of the vbios I found with this issue redefine the
pwm freq divider to insane levels (52750 Hz instead of 2500), thus breaking
fan management.

The first solution to solve this mess would be to change the length of the
table. The solution I choose was simply to avoid setting the pwm freq twice
as the other redefinitions are harmless with our current parser.

Signed-off-by: Martin Peres <martin.peres at labbri.fr>
Reported-by: Mariusz Bialonczyk <manio at skyboo.net>
Tested-by: Mariusz Bialonczyk <manio at skyboo.net>
---
 drivers/gpu/drm/nouveau/core/subdev/bios/therm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/nouveau/core/subdev/bios/therm.c b/drivers/gpu/drm/nouveau/core/subdev/bios/therm.c
index 22a2057..22ac6db 100644
--- a/drivers/gpu/drm/nouveau/core/subdev/bios/therm.c
+++ b/drivers/gpu/drm/nouveau/core/subdev/bios/therm.c
@@ -184,7 +184,8 @@ nvbios_therm_fan_parse(struct nouveau_bios *bios,
 			cur_trip->fan_duty = value;
 			break;
 		case 0x26:
-			fan->pwm_freq = value;
+			if (!fan->pwm_freq)
+				fan->pwm_freq = value;
 			break;
 		case 0x3b:
 			fan->bump_period = value;
-- 
1.8.4