Nouveau - Jan 2017 - [PATCH] nv1a,nv1f/disp: fix memory clock rate retrieval

Based on the xf86-video-nv code, NFORCE (NV1A) and NFORCE2 (NV1F) have a
different way of retrieving clocks. See the
nv_hw.c:nForceUpdateArbitrationSettings function in the original code
for how these clocks were accessed.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=54587
Cc: stable at vger.kernel.org
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
---

According to several users this improves the flickering situation
substantially, but does not fix the problems entirely. I'm guessing
there's more, but this is pretty easy to compare with the old logic.

 drm/nouveau/dispnv04/hw.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drm/nouveau/dispnv04/hw.c b/drm/nouveau/dispnv04/hw.c
index 48ad4be..b985990 100644
--- a/drm/nouveau/dispnv04/hw.c
+++ b/drm/nouveau/dispnv04/hw.c
@@ -222,6 +222,7 @@ nouveau_hw_get_clock(struct drm_device *dev, enum
nvbios_pll_type plltype)
 		uint32_t mpllP;
 
 		pci_read_config_dword(pci_get_bus_and_slot(0, 3), 0x6c, &mpllP);
+		mpllP = (mpllP >> 8) & 0xf;
 		if (!mpllP)
 			mpllP = 4;
 
@@ -232,7 +233,7 @@ nouveau_hw_get_clock(struct drm_device *dev, enum
nvbios_pll_type plltype)
 		uint32_t clock;
 
 		pci_read_config_dword(pci_get_bus_and_slot(0, 5), 0x4c, &clock);
-		return clock;
+		return clock / 1000;
 	}
 
 	ret = nouveau_hw_get_pllvals(dev, plltype, &pllvals);
-- 
2.10.2