[Intel-gfx] [PATCH 2/2]drm/i915: Generate precise PLL timing parameters according to specified clock(V3)
Ma Ling
ling.ma at intel.com
Wed Mar 18 13:13:27 CET 2009
based on different platform, construct corresponding function to provide precise pll timing.
Signed-off-by: Ma Ling <ling.ma at intel.com>
---
drivers/gpu/drm/i915/intel_display.c | 103 ++++++++++++++++++++++++++++++----
1 files changed, 91 insertions(+), 12 deletions(-)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b44c0d3..7a26b8f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -56,11 +56,13 @@ typedef struct {
} intel_p2_t;
#define INTEL_P2_NUM 2
-
-typedef struct {
+typedef struct intel_limit intel_limit_t;
+struct intel_limit {
intel_range_t dot, vco, n, m, m1, m2, p, p1;
intel_p2_t p2;
-} intel_limit_t;
+ bool (* find_pll)(const intel_limit_t *, struct drm_crtc *,
+ int, int, intel_clock_t *);
+};
#define I8XX_DOT_MIN 25000
#define I8XX_DOT_MAX 350000
@@ -198,6 +200,12 @@ typedef struct {
#define G4X_P2_DUAL_CHANNEL_LVDS_FAST 7
#define G4X_P2_DUAL_CHANNEL_LVDS_LIMIT 0
+static bool
+intel_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+ int target, int refclk, intel_clock_t *best_clock);
+static bool
+intel_g4x_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+ int target, int refclk, intel_clock_t *best_clock);
static const intel_limit_t intel_limits[] = {
{ /* INTEL_LIMIT_I8XX_DVO_DAC */
@@ -211,6 +219,7 @@ static const intel_limit_t intel_limits[] = {
.p1 = { .min = I8XX_P1_MIN, .max = I8XX_P1_MAX },
.p2 = { .dot_limit = I8XX_P2_SLOW_LIMIT,
.p2_slow = I8XX_P2_SLOW, .p2_fast = I8XX_P2_FAST },
+ .find_pll = intel_find_best_PLL,
},
{ /* INTEL_LIMIT_I8XX_LVDS */
.dot = { .min = I8XX_DOT_MIN, .max = I8XX_DOT_MAX },
@@ -223,6 +232,7 @@ static const intel_limit_t intel_limits[] = {
.p1 = { .min = I8XX_P1_LVDS_MIN, .max = I8XX_P1_LVDS_MAX },
.p2 = { .dot_limit = I8XX_P2_SLOW_LIMIT,
.p2_slow = I8XX_P2_LVDS_SLOW, .p2_fast = I8XX_P2_LVDS_FAST },
+ .find_pll = intel_find_best_PLL,
},
{ /* INTEL_LIMIT_I9XX_SDVO_DAC */
.dot = { .min = I9XX_DOT_MIN, .max = I9XX_DOT_MAX },
@@ -235,6 +245,7 @@ static const intel_limit_t intel_limits[] = {
.p1 = { .min = I9XX_P1_MIN, .max = I9XX_P1_MAX },
.p2 = { .dot_limit = I9XX_P2_SDVO_DAC_SLOW_LIMIT,
.p2_slow = I9XX_P2_SDVO_DAC_SLOW, .p2_fast = I9XX_P2_SDVO_DAC_FAST },
+ .find_pll = intel_find_best_PLL,
},
{ /* INTEL_LIMIT_I9XX_LVDS */
.dot = { .min = I9XX_DOT_MIN, .max = I9XX_DOT_MAX },
@@ -250,6 +261,7 @@ static const intel_limit_t intel_limits[] = {
*/
.p2 = { .dot_limit = I9XX_P2_LVDS_SLOW_LIMIT,
.p2_slow = I9XX_P2_LVDS_SLOW, .p2_fast = I9XX_P2_LVDS_FAST },
+ .find_pll = intel_find_best_PLL,
},
/* below parameter and function is for G4X Chipset Family*/
{ /* INTEL_LIMIT_G4X_SDVO */
@@ -265,6 +277,7 @@ static const intel_limit_t intel_limits[] = {
.p2_slow = G4X_P2_SDVO_SLOW,
.p2_fast = G4X_P2_SDVO_FAST
},
+ .find_pll = intel_g4x_find_best_PLL,
},
{ /* INTEL_LIMIT_G4X_HDMI_DAC */
.dot = { .min = G4X_DOT_HDMI_DAC_MIN, .max = G4X_DOT_HDMI_DAC_MAX },
@@ -279,6 +292,7 @@ static const intel_limit_t intel_limits[] = {
.p2_slow = G4X_P2_HDMI_DAC_SLOW,
.p2_fast = G4X_P2_HDMI_DAC_FAST
},
+ .find_pll = intel_g4x_find_best_PLL,
},
{ /* INTEL_LIMIT_G4X_SINGLE_CHANNEL_LVDS */
.dot = { .min = G4X_DOT_SINGLE_CHANNEL_LVDS_MIN,
@@ -301,6 +315,7 @@ static const intel_limit_t intel_limits[] = {
.p2_slow = G4X_P2_SINGLE_CHANNEL_LVDS_SLOW,
.p2_fast = G4X_P2_SINGLE_CHANNEL_LVDS_FAST
},
+ .find_pll = intel_g4x_find_best_PLL,
},
{ /* INTEL_LIMIT_G4X_DUAL_CHANNEL_LVDS */
.dot = { .min = G4X_DOT_DUAL_CHANNEL_LVDS_MIN,
@@ -323,6 +338,7 @@ static const intel_limit_t intel_limits[] = {
.p2_slow = G4X_P2_DUAL_CHANNEL_LVDS_SLOW,
.p2_fast = G4X_P2_DUAL_CHANNEL_LVDS_FAST
},
+ .find_pll = intel_g4x_find_best_PLL,
},
};
@@ -443,18 +459,14 @@ static bool intel_PLL_is_valid(struct drm_crtc *crtc, intel_clock_t *clock)
return true;
}
-/**
- * Returns a set of divisors for the desired target clock with the given
- * refclk, or FALSE. The returned values represent the clock equation:
- * reflck * (5 * (m1 + 2) + (m2 + 2)) / (n + 2) / p1 / p2.
- */
-static bool intel_find_best_PLL(struct drm_crtc *crtc, int target,
- int refclk, intel_clock_t *best_clock)
+static bool
+intel_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+ int target, int refclk, intel_clock_t *best_clock)
+
{
struct drm_device *dev = crtc->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
intel_clock_t clock;
- const intel_limit_t *limit = intel_limit(crtc);
int err = target;
if (IS_I9XX(dev) && intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS) &&
@@ -506,6 +518,66 @@ static bool intel_find_best_PLL(struct drm_crtc *crtc, int target,
return (err != target);
}
+static bool
+intel_g4x_find_best_PLL(const intel_limit_t *limit, struct drm_crtc *crtc,
+ int target, int refclk, intel_clock_t *best_clock)
+{
+ struct drm_device *dev = crtc->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ intel_clock_t clock;
+ int max_n;
+ bool found;
+
+ /* approximately equals target * 0.00488 */
+ int err_most = (target >> 8) + (target >> 10);
+ /* return value defult false */
+ found = false;
+
+ if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS)) {
+ if ((I915_READ(LVDS) & LVDS_CLKB_POWER_MASK) ==
+ LVDS_CLKB_POWER_UP)
+ clock.p2 = limit->p2.p2_fast;
+ else
+ clock.p2 = limit->p2.p2_slow;
+ } else {
+ if (target < limit->p2.dot_limit)
+ clock.p2 = limit->p2.p2_slow;
+ else
+ clock.p2 = limit->p2.p2_fast;
+ }
+
+ memset(best_clock, 0, sizeof(*best_clock));
+ max_n = limit->n.max;
+ /* based on hardware requriment prefer smaller n to precision */
+ for (clock.n = limit->n.min; clock.n <= max_n; clock.n++) {
+ /* based on hardware requirment prefere larger m1,m2, p1 */
+ for (clock.m1 = limit->m1.max;
+ clock.m1 >= limit->m1.min; clock.m1--) {
+ for (clock.m2 = limit->m2.max;
+ clock.m2 >= limit->m2.min; clock.m2--) {
+ for (clock.p1 = limit->p1.max;
+ clock.p1 >= limit->p1.min; clock.p1--) {
+ int this_err;
+
+ intel_clock(refclk, &clock);
+ if (!intel_PLL_is_valid(crtc, &clock))
+ continue;
+ this_err = abs(clock.dot - target) ;
+ if (this_err < err_most) {
+ *best_clock = clock;
+ err_most = this_err;
+ /* prefer smaller n to precision */
+ max_n = clock.n;
+ found = true;
+ }
+ }
+ }
+ }
+ }
+
+ return found;
+}
+
void
intel_wait_for_vblank(struct drm_device *dev)
{
@@ -924,6 +996,7 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
bool is_crt = false, is_lvds = false, is_tv = false;
struct drm_mode_config *mode_config = &dev->mode_config;
struct drm_connector *connector;
+ const intel_limit_t *limit;
int ret;
drm_vblank_pre_modeset(dev, pipe);
@@ -967,7 +1040,13 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
refclk = 48000;
}
- ok = intel_find_best_PLL(crtc, adjusted_mode->clock, refclk, &clock);
+ /*
+ * Returns a set of divisors for the desired target clock with the given
+ * refclk, or FALSE. The returned values represent the clock equation:
+ * reflck * (5 * (m1 + 2) + (m2 + 2)) / (n + 2) / p1 / p2.
+ */
+ limit = intel_limit(crtc);
+ ok = limit->find_pll(limit, crtc, adjusted_mode->clock, refclk, &clock);
if (!ok) {
DRM_ERROR("Couldn't find PLL settings for mode!\n");
return -EINVAL;
--
1.5.4.4
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