drm/nva3/pm: introduce more paranoia

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

diff --git a/drivers/gpu/drm/nouveau/nva3_pm.c b/drivers/gpu/drm/nouveau/nva3_pm.c
index 9e636e6ef6d753c52be9f79de0260f23c4f343d1..0f93c54de80c1abb193ffe0279d41895dd3bc77c 100644 (file)
--- a/drivers/gpu/drm/nouveau/nva3_pm.c
+++ b/drivers/gpu/drm/nouveau/nva3_pm.c
@@ -98,7 +98,9 @@ read_pll(struct drm_device *dev, int clk, u32 pll)
                sclk = read_clk(dev, 0x10 + clk, false);
        }
 
-       return sclk * N / (M * P);
+       if (M * P)
+               return sclk * N / (M * P);
+       return 0;
 }
 
 struct creg {
@@ -182,23 +184,26 @@ prog_pll(struct drm_device *dev, int clk, u32 pll, struct creg *reg)
        const u32 src1 = 0x004160 + (clk * 4);
        const u32 ctrl = pll + 0;
        const u32 coef = pll + 4;
-       u32 cntl;
 
        if (!reg->clk && !reg->pll) {
                NV_DEBUG(dev, "no clock for %02x\n", clk);
                return;
        }
 
-       cntl = nv_rd32(dev, ctrl) & 0xfffffff2;
        if (reg->pll) {
                nv_mask(dev, src0, 0x00000101, 0x00000101);
                nv_wr32(dev, coef, reg->pll);
-               nv_wr32(dev, ctrl, cntl | 0x00000015);
+               nv_mask(dev, ctrl, 0x00000015, 0x00000015);
+               nv_mask(dev, ctrl, 0x00000010, 0x00000000);
+               nv_wait(dev, ctrl, 0x00020000, 0x00020000);
+               nv_mask(dev, ctrl, 0x00000010, 0x00000010);
+               nv_mask(dev, ctrl, 0x00000008, 0x00000000);
                nv_mask(dev, src1, 0x00000100, 0x00000000);
                nv_mask(dev, src1, 0x00000001, 0x00000000);
        } else {
                nv_mask(dev, src1, 0x003f3141, 0x00000101 | reg->clk);
-               nv_wr32(dev, ctrl, cntl | 0x0000001d);
+               nv_mask(dev, ctrl, 0x00000018, 0x00000018);
+               udelay(20);
                nv_mask(dev, ctrl, 0x00000001, 0x00000000);
                nv_mask(dev, src0, 0x00000100, 0x00000000);
                nv_mask(dev, src0, 0x00000001, 0x00000000);