drm/nvc0/pm: minor clock readback fixes

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nvc0_pm.c b/drivers/gpu/drm/nouveau/nvc0_pm.c
index 6dc1a97..929aded 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvc0_pm.c
+++ b/drivers/gpu/drm/nouveau/nvc0_pm.c
@@ -42,12 +42,16 @@ read_vco(struct drm_device *dev, u32 dsrc)
 static u32
 read_pll(struct drm_device *dev, u32 pll)
 {
+       u32 ctrl = nv_rd32(dev, pll + 0);
        u32 coef = nv_rd32(dev, pll + 4);
        u32 P = (coef & 0x003f0000) >> 16;
        u32 N = (coef & 0x0000ff00) >> 8;
        u32 M = (coef & 0x000000ff) >> 0;
        u32 sclk, doff;
 
+       if (!(ctrl & 0x00000001))
+               return 0;
+
        switch (pll & 0xfff000) {
        case 0x00e000:
                sclk = 27000;
@@ -91,12 +95,12 @@ read_div(struct drm_device *dev, int doff, u32 dsrc, u32 dctl)
                return 100000;
        case 3:
                if (sctl & 0x80000000) {
-                       u32 sclk = read_vco(dev, dsrc);
+                       u32 sclk = read_vco(dev, dsrc + (doff * 4));
                        u32 sdiv = (sctl & 0x0000003f) + 2;
                        return (sclk * 2) / sdiv;
                }
 
-               return read_vco(dev, dsrc);
+               return read_vco(dev, dsrc + (doff * 4));
        default:
                return 0;
        }