From bcc24fb42585dc9f490cf7789a917358414bdab5 Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Mon, 31 Aug 2009 10:24:31 -0700 Subject: drm/i915: increase default latency constant (v2 w/comment) Some i915/i945 platforms have a fairly high memory latency in certain situations, so increase our constant a bit to avoid FIFO underruns. The effect should be positive on other platforms as well; we'll have a bit more insurance against a busy memory subsystem due to the extra FIFO entries. Fixes fdo bug #23368. Needed for 2.6.31. Tested-by: Sven Arvidsson Tested-by: Chris Wilson Signed-off-by: Jesse Barnes Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_display.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) (limited to 'drivers/gpu/drm/i915') diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 3fadb535885..748ed50c55c 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2005,7 +2005,21 @@ static void igd_enable_cxsr(struct drm_device *dev, unsigned long clock, return; } -const static int latency_ns = 3000; /* default for non-igd platforms */ +/* + * Latency for FIFO fetches is dependent on several factors: + * - memory configuration (speed, channels) + * - chipset + * - current MCH state + * It can be fairly high in some situations, so here we assume a fairly + * pessimal value. It's a tradeoff between extra memory fetches (if we + * set this value too high, the FIFO will fetch frequently to stay full) + * and power consumption (set it too low to save power and we might see + * FIFO underruns and display "flicker"). + * + * A value of 5us seems to be a good balance; safe for very low end + * platforms but not overly aggressive on lower latency configs. + */ +const static int latency_ns = 5000; static int intel_get_fifo_size(struct drm_device *dev, int plane) { -- cgit v1.2.3 From 58c2fb647a3cf70a90d7b33a3f2a8396a20a0bc4 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 1 Sep 2009 12:02:39 +0100 Subject: drm/i915: Unref old_obj on get_fence_reg() error path Remember to release the local reference if we fail to wait on the rendering. (Also whilst in the vicinity add some whitespace so that the phasing of the operations is clearer.) Signed-off-by: Chris Wilson Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/i915_gem.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'drivers/gpu/drm/i915') diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 0c07a755b3a..7edb5b9d579 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2267,8 +2267,6 @@ i915_gem_object_get_fence_reg(struct drm_gem_object *obj) fence_list) { old_obj = old_obj_priv->obj; - reg = &dev_priv->fence_regs[old_obj_priv->fence_reg]; - if (old_obj_priv->pin_count) continue; @@ -2290,8 +2288,11 @@ i915_gem_object_get_fence_reg(struct drm_gem_object *obj) */ i915_gem_object_flush_gpu_write_domain(old_obj); ret = i915_gem_object_wait_rendering(old_obj); - if (ret != 0) + if (ret != 0) { + drm_gem_object_unreference(old_obj); return ret; + } + break; } @@ -2299,10 +2300,14 @@ i915_gem_object_get_fence_reg(struct drm_gem_object *obj) * Zap this virtual mapping so we can set up a fence again * for this object next time we need it. */ - i915_gem_release_mmap(reg->obj); + i915_gem_release_mmap(old_obj); + i = old_obj_priv->fence_reg; + reg = &dev_priv->fence_regs[i]; + old_obj_priv->fence_reg = I915_FENCE_REG_NONE; list_del_init(&old_obj_priv->fence_list); + drm_gem_object_unreference(old_obj); } -- cgit v1.2.3