summaryrefslogtreecommitdiffstats
path: root/drivers/gpu
diff options
context:
space:
mode:
authorVille Syrjälä <ville.syrjala@linux.intel.com>2013-04-23 15:03:34 +0300
committerDaniel Vetter <daniel.vetter@ffwll.ch>2013-04-23 22:19:26 +0200
commita65851af59387146a28a928c3e7bb17dabc5db72 (patch)
tree7207836d2c2fdfbe933d790a6dc3186ebd681059 /drivers/gpu
parentae4edb8089df67d25fbd9386012a335a64aca287 (diff)
downloadop-kernel-dev-a65851af59387146a28a928c3e7bb17dabc5db72.zip
op-kernel-dev-a65851af59387146a28a928c3e7bb17dabc5db72.tar.gz
drm/i915: Make data/link N value power of two
The BIOS uses power of two values for the data/link N value. Follow suit to make the Zotac DP to dual-HDMI dongle work. v2: Clean up the magic numbers and defines Change the N clamping to be a bit easier on the eye Rename intel_reduce_ratio to intel_reduce_m_n_ratio Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=49402 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=59810 Tested-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/drm/i915/i915_reg.h12
-rw-r--r--drivers/gpu/drm/i915/intel_display.c26
2 files changed, 22 insertions, 16 deletions
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 31de7e4..83f9c26 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -2652,14 +2652,14 @@
#define _PIPEB_GMCH_DATA_M 0x71050
/* Transfer unit size for display port - 1, default is 0x3f (for TU size 64) */
-#define PIPE_GMCH_DATA_M_TU_SIZE_MASK (0x3f << 25)
-#define PIPE_GMCH_DATA_M_TU_SIZE_SHIFT 25
+#define TU_SIZE(x) (((x)-1) << 25) /* default size 64 */
+#define TU_SIZE_MASK (0x3f << 25)
-#define PIPE_GMCH_DATA_M_MASK (0xffffff)
+#define DATA_LINK_M_N_MASK (0xffffff)
+#define DATA_LINK_N_MAX (0x800000)
#define _PIPEA_GMCH_DATA_N 0x70054
#define _PIPEB_GMCH_DATA_N 0x71054
-#define PIPE_GMCH_DATA_N_MASK (0xffffff)
/*
* Computing Link M and N values for the Display Port link
@@ -2674,11 +2674,9 @@
#define _PIPEA_DP_LINK_M 0x70060
#define _PIPEB_DP_LINK_M 0x71060
-#define PIPEA_DP_LINK_M_MASK (0xffffff)
#define _PIPEA_DP_LINK_N 0x70064
#define _PIPEB_DP_LINK_N 0x71064
-#define PIPEA_DP_LINK_N_MASK (0xffffff)
#define PIPE_GMCH_DATA_M(pipe) _PIPE(pipe, _PIPEA_GMCH_DATA_M, _PIPEB_GMCH_DATA_M)
#define PIPE_GMCH_DATA_N(pipe) _PIPE(pipe, _PIPEA_GMCH_DATA_N, _PIPEB_GMCH_DATA_N)
@@ -3404,8 +3402,6 @@
#define _PIPEA_DATA_M1 (dev_priv->info->display_mmio_offset + 0x60030)
-#define TU_SIZE(x) (((x)-1) << 25) /* default size 64 */
-#define TU_SIZE_MASK 0x7e000000
#define PIPE_DATA_M1_OFFSET 0
#define _PIPEA_DATA_N1 (dev_priv->info->display_mmio_offset + 0x60034)
#define PIPE_DATA_N1_OFFSET 0
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 6e423e0..efe8299 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4084,26 +4084,36 @@ static int i830_get_display_clock_speed(struct drm_device *dev)
}
static void
-intel_reduce_ratio(uint32_t *num, uint32_t *den)
+intel_reduce_m_n_ratio(uint32_t *num, uint32_t *den)
{
- while (*num > 0xffffff || *den > 0xffffff) {
+ while (*num > DATA_LINK_M_N_MASK ||
+ *den > DATA_LINK_M_N_MASK) {
*num >>= 1;
*den >>= 1;
}
}
+static void compute_m_n(unsigned int m, unsigned int n,
+ uint32_t *ret_m, uint32_t *ret_n)
+{
+ *ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX);
+ *ret_m = div_u64((uint64_t) m * *ret_n, n);
+ intel_reduce_m_n_ratio(ret_m, ret_n);
+}
+
void
intel_link_compute_m_n(int bits_per_pixel, int nlanes,
int pixel_clock, int link_clock,
struct intel_link_m_n *m_n)
{
m_n->tu = 64;
- m_n->gmch_m = bits_per_pixel * pixel_clock;
- m_n->gmch_n = link_clock * nlanes * 8;
- intel_reduce_ratio(&m_n->gmch_m, &m_n->gmch_n);
- m_n->link_m = pixel_clock;
- m_n->link_n = link_clock;
- intel_reduce_ratio(&m_n->link_m, &m_n->link_n);
+
+ compute_m_n(bits_per_pixel * pixel_clock,
+ link_clock * nlanes * 8,
+ &m_n->gmch_m, &m_n->gmch_n);
+
+ compute_m_n(pixel_clock, link_clock,
+ &m_n->link_m, &m_n->link_n);
}
static inline bool intel_panel_use_ssc(struct drm_i915_private *dev_priv)
OpenPOWER on IntegriCloud