Created attachment 118791 [details]
vbios as extracted by envytools

Latest nouveau (after 4.2) started to refuse to change clocks on my nv43 board. Investigation showed it was simply failing to find voltage table, while such table was recognized by nvbios tool from envytools.

So, I've added patch along those lines:



    diff --git a/drm/nouveau/nvkm/subdev/bios/volt.c b/drm/nouveau/nvkm/subdev/bios/volt.c
    index 6e0a336..3e9dafa 100644
    --- a/drm/nouveau/nvkm/subdev/bios/volt.c
    +++ b/drm/nouveau/nvkm/subdev/bios/volt.c
    @@ -40,8 +40,10 @@ nvbios_volt_table(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len)
     
                    if (volt) {
                            *ver = nvbios_rd08(bios, volt + 0);
    +                       printk ("nvbios_volt_table_Ver, %d\n", *ver);
                            switch (*ver) {
                            case 0x12:
    +                       case 0x10:
                                    *hdr = 5;
                                    *cnt = nvbios_rd08(bios, volt + 2);
                                    *len = nvbios_rd08(bios, volt + 1);
    @@ -71,8 +73,11 @@ nvbios_volt_parse(struct nvkm_bios *bios, u8 *ver, u8 *hdr, u8 *cnt, u8 *len,
     {
            u16 volt = nvbios_volt_table(bios, ver, hdr, cnt, len);
            memset(info, 0x00, sizeof(*info));
    +       printk("nvbios_volt_parse called!\n");
    +       printk("volt_table_Version: %d\n", !!volt * *ver);
            switch (!!volt * *ver) {
            case 0x12:
    +       case 0x10:
                    info->type    = NVBIOS_VOLT_GPIO;
                    info->vidmask = nvbios_rd08(bios, volt + 0x04);
                    break;
    @@ -131,8 +136,10 @@ nvbios_volt_entry_parse(struct nvkm_bios *bios, int idx, u8 *ver, u8 *len,
     {
            u16 volt = nvbios_volt_entry(bios, idx, ver, len);
            memset(info, 0x00, sizeof(*info));
    +       printk("nvbios_volt_entry_parse called!\n");
            switch (!!volt * *ver) {
            case 0x12:
    +       case 0x10:
            case 0x20:
                    info->voltage = nvbios_rd08(bios, volt + 0x00) * 10000;
                    info->vid     = nvbios_rd08(bios, volt + 0x01);
     

and it seems to work.