diff options
| author | Alex Deucher <alexdeucher@gmail.com> | 2009-07-13 11:08:18 -0400 |
|---|---|---|
| committer | Dave Airlie <airlied@redhat.com> | 2009-07-15 17:13:22 +1000 |
| commit | d0e275a90a81b37409a0cfbca77581e3d235f5cf (patch) | |
| tree | 79a93ce519e39d1326bb23f38fa4549fc0950834 /drivers | |
| parent | b995e4330de0d8b1b8b9e49ce10cc6dc78e2cbba (diff) | |
drm/radeon/kms: add PLL flag to prefer frequencies <= the target freq
This is needed when using fractional feedback dividers on some IGP
chips.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_display.c | 6 | ||||
| -rw-r--r-- | drivers/gpu/drm/radeon/radeon_mode.h | 1 |
2 files changed, 6 insertions, 1 deletions
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index 3efcf1a526b..bc312f3d9a0 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -491,7 +491,11 @@ void radeon_compute_pll(struct radeon_pll *pll, tmp += (uint64_t)pll->reference_freq * 1000 * frac_feedback_div; current_freq = radeon_div(tmp, ref_div * post_div); - error = abs(current_freq - freq); + if (flags & RADEON_PLL_PREFER_CLOSEST_LOWER) { + error = freq - current_freq; + error = error < 0 ? 0xffffffff : error; + } else + error = abs(current_freq - freq); vco_diff = abs(vco - best_vco); if ((best_vco == 0 && error < best_error) || diff --git a/drivers/gpu/drm/radeon/radeon_mode.h b/drivers/gpu/drm/radeon/radeon_mode.h index 86f766e868e..38c1dd08244 100644 --- a/drivers/gpu/drm/radeon/radeon_mode.h +++ b/drivers/gpu/drm/radeon/radeon_mode.h @@ -124,6 +124,7 @@ struct radeon_tmds_pll { #define RADEON_PLL_PREFER_LOW_POST_DIV (1 << 8) #define RADEON_PLL_PREFER_HIGH_POST_DIV (1 << 9) #define RADEON_PLL_USE_FRAC_FB_DIV (1 << 10) +#define RADEON_PLL_PREFER_CLOSEST_LOWER (1 << 11) struct radeon_pll { uint16_t reference_freq; |