[Nouveau] [PATCH] volt: Fix for some cards having 0 maximum voltage

[Mark Menzynski]

Some, mostly Fermi, vbioses appear to have zero max voltage. That causes Nouveau to not parse voltage entries, thus users not being able to set higher clocks.

When changing this value Nvidia driver still appeared to ignore it, and I wasn't able to find out why, thus the code is ignoring the value if it is zero.

CC: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
Signed-off-by: Mark Menzynski <mmenzyns at redhat.com>
---
 drm/nouveau/nvkm/subdev/bios/volt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drm/nouveau/nvkm/subdev/bios/volt.c b/drm/nouveau/nvkm/subdev/bios/volt.c
index 7143ea46..33a9fb5a 100644
--- a/drm/nouveau/nvkm/subdev/bios/volt.c
+++ b/drm/nouveau/nvkm/subdev/bios/volt.c
@@ -96,6 +96,8 @@ nvbios_volt_parse(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len,
 		info->min     = min(info->base,
 				    info->base + info->step * info->vidmask);
 		info->max     = nvbios_rd32(bios, volt + 0x0e);
+		if (!info->max)
+			info->max = max(info->base, info->base + info->step * info->vidmask);
 		break;
 	case 0x50:
 		info->min     = nvbios_rd32(bios, volt + 0x0a);
-- 
2.21.0