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-rw-r--r--drivers/gpu/drm/i915/i915_reg.h2
-rw-r--r--drivers/gpu/drm/i915/intel_display.c186
2 files changed, 113 insertions, 75 deletions
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 6c085848409..897a116cad1 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1618,7 +1618,7 @@
#define I830_FIFO_LINE_SIZE 32
#define I945_FIFO_SIZE 127 /* 945 & 965 */
#define I915_FIFO_SIZE 95
-#define I855GM_FIFO_SIZE 255
+#define I855GM_FIFO_SIZE 127 /* In cachelines */
#define I830_FIFO_SIZE 95
#define I915_MAX_WM 0x3f
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 984645e26a2..3fa0d63c83b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1623,44 +1623,67 @@ static struct intel_watermark_params igd_cursor_hplloff_wm = {
IGD_FIFO_LINE_SIZE
};
static struct intel_watermark_params i945_wm_info = {
- I915_FIFO_LINE_SIZE,
+ I945_FIFO_SIZE,
I915_MAX_WM,
1,
- 0,
- IGD_FIFO_LINE_SIZE
+ 2,
+ I915_FIFO_LINE_SIZE
};
static struct intel_watermark_params i915_wm_info = {
- I945_FIFO_SIZE,
+ I915_FIFO_SIZE,
I915_MAX_WM,
1,
- 0,
+ 2,
I915_FIFO_LINE_SIZE
};
static struct intel_watermark_params i855_wm_info = {
I855GM_FIFO_SIZE,
I915_MAX_WM,
1,
- 0,
+ 2,
I830_FIFO_LINE_SIZE
};
static struct intel_watermark_params i830_wm_info = {
I830_FIFO_SIZE,
I915_MAX_WM,
1,
- 0,
+ 2,
I830_FIFO_LINE_SIZE
};
+/**
+ * intel_calculate_wm - calculate watermark level
+ * @clock_in_khz: pixel clock
+ * @wm: chip FIFO params
+ * @pixel_size: display pixel size
+ * @latency_ns: memory latency for the platform
+ *
+ * Calculate the watermark level (the level at which the display plane will
+ * start fetching from memory again). Each chip has a different display
+ * FIFO size and allocation, so the caller needs to figure that out and pass
+ * in the correct intel_watermark_params structure.
+ *
+ * As the pixel clock runs, the FIFO will be drained at a rate that depends
+ * on the pixel size. When it reaches the watermark level, it'll start
+ * fetching FIFO line sized based chunks from memory until the FIFO fills
+ * past the watermark point. If the FIFO drains completely, a FIFO underrun
+ * will occur, and a display engine hang could result.
+ */
static unsigned long intel_calculate_wm(unsigned long clock_in_khz,
struct intel_watermark_params *wm,
int pixel_size,
unsigned long latency_ns)
{
- unsigned long bytes_required, wm_size;
+ unsigned long entries_required, wm_size;
+
+ entries_required = (clock_in_khz * pixel_size * latency_ns) / 1000000;
+ entries_required /= wm->cacheline_size;
+
+ DRM_DEBUG("FIFO entries required for mode: %d\n", entries_required);
- bytes_required = (clock_in_khz * pixel_size * latency_ns) / 1000000;
- bytes_required /= wm->cacheline_size;
- wm_size = wm->fifo_size - bytes_required - wm->guard_size;
+ wm_size = wm->fifo_size - (entries_required + wm->guard_size);
+
+ DRM_DEBUG("FIFO watermark level: %d\n", wm_size);
if (wm_size > wm->max_wm)
wm_size = wm->max_wm;
@@ -1799,8 +1822,37 @@ static void igd_enable_cxsr(struct drm_device *dev, unsigned long clock,
return;
}
-const static int latency_ns = 5000; /* default for non-igd platforms */
+const static int latency_ns = 3000; /* default for non-igd platforms */
+
+static int intel_get_fifo_size(struct drm_device *dev, int plane)
+{
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ uint32_t dsparb = I915_READ(DSPARB);
+ int size;
+
+ if (IS_I9XX(dev)) {
+ if (plane == 0)
+ size = dsparb & 0x7f;
+ else
+ size = ((dsparb >> DSPARB_CSTART_SHIFT) & 0x7f) -
+ (dsparb & 0x7f);
+ } else if (IS_I85X(dev)) {
+ if (plane == 0)
+ size = dsparb & 0x1ff;
+ else
+ size = ((dsparb >> DSPARB_BEND_SHIFT) & 0x1ff) -
+ (dsparb & 0x1ff);
+ size >>= 1; /* Convert to cachelines */
+ } else {
+ size = dsparb & 0x7f;
+ size >>= 1; /* Convert to cachelines */
+ }
+
+ DRM_DEBUG("FIFO size - (0x%08x) %s: %d\n", dsparb, plane ? "B" : "A",
+ size);
+ return size;
+}
static void i965_update_wm(struct drm_device *dev)
{
@@ -1817,101 +1869,87 @@ static void i9xx_update_wm(struct drm_device *dev, int planea_clock,
int planeb_clock, int sr_hdisplay, int pixel_size)
{
struct drm_i915_private *dev_priv = dev->dev_private;
- uint32_t fwater_lo = I915_READ(FW_BLC) & MM_FIFO_WATERMARK;
- uint32_t fwater_hi = I915_READ(FW_BLC2) & LM_FIFO_WATERMARK;
- int bsize, asize, cwm, bwm = 1, awm = 1, srwm = 1;
- uint32_t dsparb = I915_READ(DSPARB);
- int planea_entries, planeb_entries;
- struct intel_watermark_params *wm_params;
+ uint32_t fwater_lo;
+ uint32_t fwater_hi;
+ int total_size, cacheline_size, cwm, srwm = 1;
+ int planea_wm, planeb_wm;
+ struct intel_watermark_params planea_params, planeb_params;
unsigned long line_time_us;
int sr_clock, sr_entries = 0;
+ /* Create copies of the base settings for each pipe */
if (IS_I965GM(dev) || IS_I945GM(dev))
- wm_params = &i945_wm_info;
+ planea_params = planeb_params = i945_wm_info;
else if (IS_I9XX(dev))
- wm_params = &i915_wm_info;
+ planea_params = planeb_params = i915_wm_info;
else
- wm_params = &i855_wm_info;
-
- planea_entries = intel_calculate_wm(planea_clock, wm_params,
- pixel_size, latency_ns);
- planeb_entries = intel_calculate_wm(planeb_clock, wm_params,
- pixel_size, latency_ns);
+ planea_params = planeb_params = i855_wm_info;
- DRM_DEBUG("FIFO entries - A: %d, B: %d\n", planea_entries,
- planeb_entries);
+ /* Grab a couple of global values before we overwrite them */
+ total_size = planea_params.fifo_size;
+ cacheline_size = planea_params.cacheline_size;
- if (IS_I9XX(dev)) {
- asize = dsparb & 0x7f;
- bsize = (dsparb >> DSPARB_CSTART_SHIFT) & 0x7f;
- } else {
- asize = dsparb & 0x1ff;
- bsize = (dsparb >> DSPARB_BEND_SHIFT) & 0x1ff;
- }
- DRM_DEBUG("FIFO size - A: %d, B: %d\n", asize, bsize);
+ /* Update per-plane FIFO sizes */
+ planea_params.fifo_size = intel_get_fifo_size(dev, 0);
+ planeb_params.fifo_size = intel_get_fifo_size(dev, 1);
- /* Two extra entries for padding */
- awm = asize - (planea_entries + 2);
- bwm = bsize - (planeb_entries + 2);
-
- /* Sanity check against potentially bad FIFO allocations */
- if (awm <= 0) {
- /* pipe is on but has too few FIFO entries */
- if (planea_entries != 0)
- DRM_DEBUG("plane A needs more FIFO entries\n");
- awm = 1;
- }
- if (bwm <= 0) {
- if (planeb_entries != 0)
- DRM_DEBUG("plane B needs more FIFO entries\n");
- bwm = 1;
- }
+ planea_wm = intel_calculate_wm(planea_clock, &planea_params,
+ pixel_size, latency_ns);
+ planeb_wm = intel_calculate_wm(planeb_clock, &planeb_params,
+ pixel_size, latency_ns);
+ DRM_DEBUG("FIFO watermarks - A: %d, B: %d\n", planea_wm, planeb_wm);
/*
* Overlay gets an aggressive default since video jitter is bad.
*/
cwm = 2;
- /* Calc sr entries for one pipe configs */
+ /* Calc sr entries for one plane configs */
if (!planea_clock || !planeb_clock) {
+ /* self-refresh has much higher latency */
+ const static int sr_latency_ns = 6000;
+
sr_clock = planea_clock ? planea_clock : planeb_clock;
- line_time_us = (sr_hdisplay * 1000) / sr_clock;
- sr_entries = (((latency_ns / line_time_us) + 1) * pixel_size *
- sr_hdisplay) / 1000;
- sr_entries = roundup(sr_entries / wm_params->cacheline_size, 1);
- if (sr_entries < wm_params->fifo_size)
- srwm = wm_params->fifo_size - sr_entries;
+ line_time_us = ((sr_hdisplay * 1000) / sr_clock);
+
+ /* Use ns/us then divide to preserve precision */
+ sr_entries = (((sr_latency_ns / line_time_us) + 1) *
+ pixel_size * sr_hdisplay) / 1000;
+ sr_entries = roundup(sr_entries / cacheline_size, 1);
+ DRM_DEBUG("self-refresh entries: %d\n", sr_entries);
+ srwm = total_size - sr_entries;
+ if (srwm < 0)
+ srwm = 1;
}
DRM_DEBUG("Setting FIFO watermarks - A: %d, B: %d, C: %d, SR %d\n",
- awm, bwm, cwm, srwm);
+ planea_wm, planeb_wm, cwm, srwm);
- fwater_lo = fwater_lo | ((bwm & 0x3f) << 16) | (awm & 0x3f);
- fwater_hi = fwater_hi | (cwm & 0x1f);
+ fwater_lo = ((planeb_wm & 0x3f) << 16) | (planea_wm & 0x3f);
+ fwater_hi = (cwm & 0x1f);
+
+ /* Set request length to 8 cachelines per fetch */
+ fwater_lo = fwater_lo | (1 << 24) | (1 << 8);
+ fwater_hi = fwater_hi | (1 << 8);
I915_WRITE(FW_BLC, fwater_lo);
I915_WRITE(FW_BLC2, fwater_hi);
if (IS_I9XX(dev))
- I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN | (srwm & 0x3f));
+ I915_WRITE(FW_BLC_SELF, (srwm & 0x3f));
}
static void i830_update_wm(struct drm_device *dev, int planea_clock,
int pixel_size)
{
struct drm_i915_private *dev_priv = dev->dev_private;
- uint32_t dsparb = I915_READ(DSPARB);
uint32_t fwater_lo = I915_READ(FW_BLC) & MM_FIFO_WATERMARK;
- unsigned int asize, awm;
- int planea_entries;
-
- planea_entries = intel_calculate_wm(planea_clock, &i830_wm_info,
- pixel_size, latency_ns);
-
- asize = dsparb & 0x7f;
+ int planea_wm;
- awm = asize - planea_entries;
+ i830_wm_info.fifo_size = intel_get_fifo_size(dev, 0);
- fwater_lo = fwater_lo | awm;
+ planea_wm = intel_calculate_wm(planea_clock, &i830_wm_info,
+ pixel_size, latency_ns);
+ fwater_lo = fwater_lo | planea_wm;
I915_WRITE(FW_BLC, fwater_lo);
}
@@ -1984,7 +2022,7 @@ static void intel_update_watermarks(struct drm_device *dev)
if (enabled <= 0)
return;
- /* Single pipe configs can enable self refresh */
+ /* Single plane configs can enable self refresh */
if (enabled == 1 && IS_IGD(dev))
igd_enable_cxsr(dev, sr_clock, pixel_size);
else if (IS_IGD(dev))
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-18 17:51:16 +0000