drm/nv50/pm: avoid touching dom6/vdec clocks if perflvl doesn't define it

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

diff --git a/drivers/gpu/drm/nouveau/nv50_pm.c b/drivers/gpu/drm/nouveau/nv50_pm.c
index 9d61bd4..0b82c60 100644 (file)
--- a/drivers/gpu/drm/nouveau/nv50_pm.c
+++ b/drivers/gpu/drm/nouveau/nv50_pm.c
@@ -485,7 +485,8 @@ nv50_pm_clocks_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl)
         * clock domains work, i suspect at least some of them can also be
         * tied to xpll...
         */
-       info->amast = info->pdivs = 0;
+       info->amast = nv_rd32(dev, 0x00c040);
+       info->pdivs = read_div(dev);
        if (perflvl->vdec) {
                /* see how close we can get using nvclk as a source */
                clk = calc_div(perflvl->core, perflvl->vdec, &P1);
@@ -498,12 +499,12 @@ nv50_pm_clocks_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl)
                out = calc_div(out, perflvl->vdec, &P2);
 
                /* select whichever gets us closest */
+               info->amast &= ~0x00000c00;
+               info->pdivs &= ~0x00000700;
                if (abs((int)perflvl->vdec - clk) <=
                    abs((int)perflvl->vdec - out)) {
                        if (dev_priv->chipset != 0x98)
                                info->amast |= 0x00000c00;
-                       else
-                               info->amast |= 0x00000000;
                        info->pdivs |= P1 << 8;
                } else {
                        info->amast |= 0x00000800;
@@ -514,23 +515,22 @@ nv50_pm_clocks_pre(struct drm_device *dev, struct nouveau_pm_level *perflvl)
        /* dom6: nfi what this is, but we're limited to various combinations
         * of the host clock frequency
         */
-       if (clk_same(perflvl->dom6, read_clk(dev, clk_src_href))) {
-               info->amast |= 0x00000000;
-               info->pdivs |= read_div(dev) & 0x00000007;
-       } else
-       if (clk_same(perflvl->dom6, read_clk(dev, clk_src_hclk))) {
-               info->amast |= 0x08000000;
-               info->pdivs |= read_div(dev) & 0x00000007;
-       } else
        if (perflvl->dom6) {
-               clk = read_clk(dev, clk_src_hclk) * 3;
-               clk = calc_div(clk, perflvl->dom6, &P1);
+               info->amast &= ~0x0c000000;
+               if (clk_same(perflvl->dom6, read_clk(dev, clk_src_href))) {
+                       info->amast |= 0x00000000;
+               } else
+               if (clk_same(perflvl->dom6, read_clk(dev, clk_src_hclk))) {
+                       info->amast |= 0x08000000;
+               } else {
+                       clk = read_clk(dev, clk_src_hclk) * 3;
+                       clk = calc_div(clk, perflvl->dom6, &P1);
 
-               info->amast |= 0x0c000000;
-               info->pdivs |= P1;
+                       info->amast |= 0x0c000000;
+                       info->pdivs  = (info->pdivs & ~0x00000007) | P1;
+               }
        }
 
-
        return info;
 error:
        kfree(info);