drm/nouveau: determine timing crystal freq from straps

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This commit is contained in:
Ben Skeggs 2011-07-21 15:39:06 +10:00
parent 93e692dc5f
commit f2cbe46f14
2 changed files with 19 additions and 1 deletions

View File

@ -680,6 +680,7 @@ struct drm_nouveau_private {
/* exact chipset, derived from NV_PMC_BOOT_0 */
int chipset;
int flags;
u32 crystal;
void __iomem *mmio;

View File

@ -984,7 +984,7 @@ static int nouveau_remove_conflicting_drivers(struct drm_device *dev)
int nouveau_load(struct drm_device *dev, unsigned long flags)
{
struct drm_nouveau_private *dev_priv;
uint32_t reg0;
uint32_t reg0, strap;
resource_size_t mmio_start_offs;
int ret;
@ -1074,6 +1074,23 @@ int nouveau_load(struct drm_device *dev, unsigned long flags)
NV_INFO(dev, "Detected an NV%2x generation card (0x%08x)\n",
dev_priv->card_type, reg0);
/* determine frequency of timing crystal */
strap = nv_rd32(dev, 0x101000);
if ( dev_priv->chipset < 0x17 ||
(dev_priv->chipset >= 0x20 && dev_priv->chipset <= 0x25))
strap &= 0x00000040;
else
strap &= 0x00400040;
switch (strap) {
case 0x00000000: dev_priv->crystal = 13500; break;
case 0x00000040: dev_priv->crystal = 14318; break;
case 0x00400000: dev_priv->crystal = 27000; break;
case 0x00400040: dev_priv->crystal = 25000; break;
}
NV_DEBUG(dev, "crystal freq: %dKHz\n", dev_priv->crystal);
/* Determine whether we'll attempt acceleration or not, some
* cards are disabled by default here due to them being known
* non-functional, or never been tested due to lack of hw.