From: Chris Wilson Date: Wed, 19 Jan 2011 15:04:42 +0000 (+0000) Subject: drm/i915: Include TLB miss latency in g4x watermark computations X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=417ae1476de3ae9689a374d70565f41b3474641e;p=deliverable%2Flinux.git drm/i915: Include TLB miss latency in g4x watermark computations Reports of FIFO underruns are still persisting on gm45. References: https://bugs.freedesktop.org/show_bug.cgi?id=27589 Signed-off-by: Chris Wilson --- diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 2f58d97972db..2c2ecab6627f 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3604,89 +3604,177 @@ static void pineview_update_wm(struct drm_device *dev, int planea_clock, } } -static void g4x_update_wm(struct drm_device *dev, int planea_clock, - int planeb_clock, int sr_hdisplay, int sr_htotal, - int pixel_size) +static bool g4x_compute_wm0(struct drm_device *dev, + int plane, + const struct intel_watermark_params *display, + int display_latency_ns, + const struct intel_watermark_params *cursor, + int cursor_latency_ns, + int *plane_wm, + int *cursor_wm) { - struct drm_i915_private *dev_priv = dev->dev_private; - int total_size, cacheline_size; - int planea_wm, planeb_wm, cursora_wm, cursorb_wm, cursor_sr; - struct intel_watermark_params planea_params, planeb_params; - unsigned long line_time_us; - int sr_clock, sr_entries = 0, entries_required; + struct drm_crtc *crtc; + int htotal, hdisplay, clock, pixel_size; + int line_time_us, line_count; + int entries, tlb_miss; - /* Create copies of the base settings for each pipe */ - planea_params = planeb_params = g4x_wm_info; + crtc = intel_get_crtc_for_plane(dev, plane); + if (crtc->fb == NULL || !crtc->enabled) + return false; - /* Grab a couple of global values before we overwrite them */ - total_size = planea_params.fifo_size; - cacheline_size = planea_params.cacheline_size; + htotal = crtc->mode.htotal; + hdisplay = crtc->mode.hdisplay; + clock = crtc->mode.clock; + pixel_size = crtc->fb->bits_per_pixel / 8; - /* - * Note: we need to make sure we don't overflow for various clock & - * latency values. - * clocks go from a few thousand to several hundred thousand. - * latency is usually a few thousand - */ - entries_required = ((planea_clock / 1000) * pixel_size * latency_ns) / - 1000; - entries_required = DIV_ROUND_UP(entries_required, G4X_FIFO_LINE_SIZE); - planea_wm = entries_required + planea_params.guard_size; + /* Use the small buffer method to calculate plane watermark */ + entries = ((clock * pixel_size / 1000) * display_latency_ns) / 1000; + tlb_miss = display->fifo_size*display->cacheline_size - hdisplay * 8; + if (tlb_miss > 0) + entries += tlb_miss; + entries = DIV_ROUND_UP(entries, display->cacheline_size); + *plane_wm = entries + display->guard_size; + if (*plane_wm > (int)display->max_wm) + *plane_wm = display->max_wm; - entries_required = ((planeb_clock / 1000) * pixel_size * latency_ns) / - 1000; - entries_required = DIV_ROUND_UP(entries_required, G4X_FIFO_LINE_SIZE); - planeb_wm = entries_required + planeb_params.guard_size; + /* Use the large buffer method to calculate cursor watermark */ + line_time_us = ((htotal * 1000) / clock); + line_count = (cursor_latency_ns / line_time_us + 1000) / 1000; + entries = line_count * 64 * pixel_size; + tlb_miss = cursor->fifo_size*cursor->cacheline_size - hdisplay * 8; + if (tlb_miss > 0) + entries += tlb_miss; + entries = DIV_ROUND_UP(entries, cursor->cacheline_size); + *cursor_wm = entries + cursor->guard_size; + if (*cursor_wm > (int)cursor->max_wm) + *cursor_wm = (int)cursor->max_wm; - cursora_wm = cursorb_wm = 16; - cursor_sr = 32; + return true; +} - DRM_DEBUG("FIFO watermarks - A: %d, B: %d\n", planea_wm, planeb_wm); +/* + * Check the wm result. + * + * If any calculated watermark values is larger than the maximum value that + * can be programmed into the associated watermark register, that watermark + * must be disabled. + */ +static bool g4x_check_srwm(struct drm_device *dev, + int display_wm, int cursor_wm, + const struct intel_watermark_params *display, + const struct intel_watermark_params *cursor) +{ + DRM_DEBUG_KMS("SR watermark: display plane %d, cursor %d\n", + display_wm, cursor_wm); - /* Calc sr entries for one plane configs */ - if (sr_hdisplay && (!planea_clock || !planeb_clock)) { - /* self-refresh has much higher latency */ - static const int sr_latency_ns = 12000; + if (display_wm > display->max_wm) { + DRM_DEBUG_KMS("display watermark is too large(%d), disabling\n", + display_wm, display->max_wm); + return false; + } - sr_clock = planea_clock ? planea_clock : planeb_clock; - line_time_us = ((sr_htotal * 1000) / sr_clock); + if (cursor_wm > cursor->max_wm) { + DRM_DEBUG_KMS("cursor watermark is too large(%d), disabling\n", + cursor_wm, cursor->max_wm); + return false; + } - /* Use ns/us then divide to preserve precision */ - sr_entries = (((sr_latency_ns / line_time_us) + 1000) / 1000) * - pixel_size * sr_hdisplay; - sr_entries = DIV_ROUND_UP(sr_entries, cacheline_size); + if (!(display_wm || cursor_wm)) { + DRM_DEBUG_KMS("SR latency is 0, disabling\n"); + return false; + } - entries_required = (((sr_latency_ns / line_time_us) + - 1000) / 1000) * pixel_size * 64; - entries_required = DIV_ROUND_UP(entries_required, - g4x_cursor_wm_info.cacheline_size); - cursor_sr = entries_required + g4x_cursor_wm_info.guard_size; + return true; +} - if (cursor_sr > g4x_cursor_wm_info.max_wm) - cursor_sr = g4x_cursor_wm_info.max_wm; - DRM_DEBUG_KMS("self-refresh watermark: display plane %d " - "cursor %d\n", sr_entries, cursor_sr); +static bool g4x_compute_srwm(struct drm_device *dev, + int hdisplay, int htotal, + int pixel_size, int clock, int latency_ns, + const struct intel_watermark_params *display, + const struct intel_watermark_params *cursor, + int *display_wm, int *cursor_wm) +{ + unsigned long line_time_us; + int line_count, line_size; + int small, large; + int entries; - I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN); - } else { - /* Turn off self refresh if both pipes are enabled */ - I915_WRITE(FW_BLC_SELF, I915_READ(FW_BLC_SELF) - & ~FW_BLC_SELF_EN); + if (!latency_ns) { + *display_wm = *cursor_wm = 0; + return false; } - DRM_DEBUG("Setting FIFO watermarks - A: %d, B: %d, SR %d\n", - planea_wm, planeb_wm, sr_entries); + line_time_us = (htotal * 1000) / clock; + line_count = (latency_ns / line_time_us + 1000) / 1000; + line_size = hdisplay * pixel_size; + + /* Use the minimum of the small and large buffer method for primary */ + small = ((clock * pixel_size / 1000) * latency_ns) / 1000; + large = line_count * line_size; + + entries = DIV_ROUND_UP(min(small, large), display->cacheline_size); + *display_wm = entries + display->guard_size; + + /* calculate the self-refresh watermark for display cursor */ + entries = line_count * pixel_size * 64; + entries = DIV_ROUND_UP(entries, cursor->cacheline_size); + *cursor_wm = entries + cursor->guard_size; + + return g4x_check_srwm(dev, + *display_wm, *cursor_wm, + display, cursor); +} + +static void g4x_update_wm(struct drm_device *dev, + int planea_clock, int planeb_clock, + int hdisplay, int htotal, int pixel_size) +{ + static const int sr_latency_ns = 12000; + struct drm_i915_private *dev_priv = dev->dev_private; + int planea_wm, planeb_wm, cursora_wm, cursorb_wm; + int enabled = 0, plane_sr, cursor_sr, clock; + + if (g4x_compute_wm0(dev, 0, + &g4x_wm_info, latency_ns, + &g4x_cursor_wm_info, latency_ns, + &planea_wm, &cursora_wm)) + enabled++; + + if (g4x_compute_wm0(dev, 1, + &g4x_wm_info, latency_ns, + &g4x_cursor_wm_info, latency_ns, + &planeb_wm, &cursorb_wm)) + enabled++; + + plane_sr = cursor_sr = 0; + clock = planea_clock ? planea_clock : planeb_clock; + if (enabled == 1 && + g4x_compute_srwm(dev, hdisplay, htotal, pixel_size, + clock, sr_latency_ns, + &g4x_wm_info, + &g4x_cursor_wm_info, + &plane_sr, &cursor_sr)) + I915_WRITE(FW_BLC_SELF, FW_BLC_SELF_EN); + else + I915_WRITE(FW_BLC_SELF, + I915_READ(FW_BLC_SELF) & ~FW_BLC_SELF_EN); - planea_wm &= 0x3f; - planeb_wm &= 0x3f; + DRM_DEBUG("Setting FIFO watermarks - A: plane=%d, cursor=%d, B: plane=%d, cursor=%d, SR: plane=%d, cursor=%d\n", + planea_wm, cursora_wm, + planeb_wm, cursorb_wm, + plane_sr, cursor_sr); - I915_WRITE(DSPFW1, (sr_entries << DSPFW_SR_SHIFT) | + I915_WRITE(DSPFW1, + (plane_sr << DSPFW_SR_SHIFT) | (cursorb_wm << DSPFW_CURSORB_SHIFT) | - (planeb_wm << DSPFW_PLANEB_SHIFT) | planea_wm); - I915_WRITE(DSPFW2, (I915_READ(DSPFW2) & DSPFW_CURSORA_MASK) | + (planeb_wm << DSPFW_PLANEB_SHIFT) | + planea_wm); + I915_WRITE(DSPFW2, + (I915_READ(DSPFW2) & DSPFW_CURSORA_MASK) | (cursora_wm << DSPFW_CURSORA_SHIFT)); /* HPLL off in SR has some issues on G4x... disable it */ - I915_WRITE(DSPFW3, (I915_READ(DSPFW3) & ~DSPFW_HPLL_SR_EN) | + I915_WRITE(DSPFW3, + (I915_READ(DSPFW3) & ~DSPFW_HPLL_SR_EN) | (cursor_sr << DSPFW_CURSOR_SR_SHIFT)); } @@ -3743,8 +3831,8 @@ static void i965_update_wm(struct drm_device *dev, int planea_clock, srwm); /* 965 has limitations... */ - I915_WRITE(DSPFW1, (srwm << DSPFW_SR_SHIFT) | (8 << 16) | (8 << 8) | - (8 << 0)); + I915_WRITE(DSPFW1, (srwm << DSPFW_SR_SHIFT) | + (8 << 16) | (8 << 8) | (8 << 0)); I915_WRITE(DSPFW2, (8 << 8) | (8 << 0)); /* update cursor SR watermark */ I915_WRITE(DSPFW3, (cursor_sr << DSPFW_CURSOR_SR_SHIFT)); diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index 74db2557d644..5ce4a5f13de1 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -217,6 +217,13 @@ intel_get_crtc_for_pipe(struct drm_device *dev, int pipe) return dev_priv->pipe_to_crtc_mapping[pipe]; } +static inline struct drm_crtc * +intel_get_crtc_for_plane(struct drm_device *dev, int plane) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + return dev_priv->plane_to_crtc_mapping[plane]; +} + struct intel_unpin_work { struct work_struct work; struct drm_device *dev;