[Intel-gfx] [PATCH 06/13] drm/i915: Remove use of gtt_mappable_entries

[Ben Widawsky]

Mappable_end, ie. size is almost always what you want as opposed to the
number of entries. Since we already have that information, we can scrap
the number of entries and only calculate it when needed.

If gtt_start is !0, this will have slightly different behavior. This
difference can only occur in DRI1, and exists when we try to kick out
the firmware fb. The new code seems like a bugfix to me.

The other case where we've changed the behavior is during init we check
the mappable region against our current known upper and lower limits
(64MB, and 512MB). This now matches the comment, and makes things more
convenient after removing gtt_mappable_entries.

Also worth noting is the setting of mappable_end is taken out of setup
because we do it earlier now in the DRI2 case and therefore need to add
that tiny hunk to support the DRI1 IOCTL.

Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
---
 drivers/gpu/drm/i915/i915_dma.c     |  8 ++++----
 drivers/gpu/drm/i915/i915_gem.c     |  1 +
 drivers/gpu/drm/i915/i915_gem_gtt.c | 15 +++++++--------
 drivers/gpu/drm/i915/intel_fb.c     |  3 +--
 4 files changed, 13 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c
index b8f42e0..03a97d1 100644
--- a/drivers/gpu/drm/i915/i915_dma.c
+++ b/drivers/gpu/drm/i915/i915_dma.c
@@ -1418,8 +1418,8 @@ static void i915_kick_out_firmware_fb(struct drm_i915_private *dev_priv)
 		return;
 
 	ap->ranges[0].base = dev_priv->gtt.mappable_base;
-	ap->ranges[0].size =
-		dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT;
+	ap->ranges[0].size = dev_priv->gtt.mappable_end - dev_priv->gtt.start;
+
 	primary =
 		pdev->resource[PCI_ROM_RESOURCE].flags & IORESOURCE_ROM_SHADOW;
 
@@ -1533,7 +1533,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 		goto put_gmch;
 	}
 
-	aperture_size = dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT;
+	aperture_size = dev_priv->gtt.mappable_end;
 
 	dev_priv->gtt.mappable =
 		io_mapping_create_wc(dev_priv->gtt.mappable_base,
@@ -1690,7 +1690,7 @@ int i915_driver_unload(struct drm_device *dev)
 	if (dev_priv->mm.gtt_mtrr >= 0) {
 		mtrr_del(dev_priv->mm.gtt_mtrr,
 			 dev_priv->gtt.mappable_base,
-			 dev_priv->mm.gtt->gtt_mappable_entries * PAGE_SIZE);
+			 dev_priv->gtt.mappable_end);
 		dev_priv->mm.gtt_mtrr = -1;
 	}
 
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 4ec66a9..e84c9f9 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -166,6 +166,7 @@ i915_gem_init_ioctl(struct drm_device *dev, void *data,
 	mutex_lock(&dev->struct_mutex);
 	i915_gem_setup_global_gtt(dev, args->gtt_start, args->gtt_end,
 				  args->gtt_end);
+	dev_priv->gtt.mappable_end = args->gtt_end;
 	mutex_unlock(&dev->struct_mutex);
 
 	return 0;
diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 4461a49..46e9544 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -557,7 +557,6 @@ void i915_gem_setup_global_gtt(struct drm_device *dev,
 	}
 
 	dev_priv->gtt.start = start;
-	dev_priv->gtt.mappable_end = mappable_end;
 	dev_priv->gtt.total = end - start;
 
 	/* Clear any non-preallocated blocks */
@@ -596,7 +595,7 @@ void i915_gem_init_global_gtt(struct drm_device *dev)
 	int ret;
 
 	gtt_size = dev_priv->mm.gtt->gtt_total_entries << PAGE_SHIFT;
-	mappable_size = dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT;
+	mappable_size = dev_priv->gtt.mappable_end;
 
 	if (intel_enable_ppgtt(dev) && HAS_ALIASING_PPGTT(dev)) {
 		/* PPGTT pdes are stolen from global gtt ptes, so shrink the
@@ -720,6 +719,7 @@ int i915_gem_gtt_init(struct drm_device *dev)
 	/* For GEN6+ the PTEs for the ggtt live at 2MB + BAR0 */
 	gtt_bus_addr = pci_resource_start(dev->pdev, 0) + (2<<20);
 	dev_priv->gtt.mappable_base = pci_resource_start(dev->pdev, 2);
+	dev_priv->gtt.mappable_end = pci_resource_len(dev->pdev, 2);
 
 	/* i9xx_setup */
 	pci_read_config_word(dev->pdev, SNB_GMCH_CTRL, &snb_gmch_ctl);
@@ -730,14 +730,13 @@ int i915_gem_gtt_init(struct drm_device *dev)
 	else
 		dev_priv->mm.gtt->stolen_size = gen7_get_stolen_size(snb_gmch_ctl);
 
-	dev_priv->mm.gtt->gtt_mappable_entries = pci_resource_len(dev->pdev, 2) >> PAGE_SHIFT;
 	/* 64/512MB is the current min/max we actually know of, but this is just a
 	 * coarse sanity check.
 	 */
-	if ((dev_priv->mm.gtt->gtt_mappable_entries >> 8) < 64 ||
-	    dev_priv->mm.gtt->gtt_mappable_entries > dev_priv->mm.gtt->gtt_total_entries) {
-		DRM_ERROR("Unknown GMADR entries (%d)\n",
-			  dev_priv->mm.gtt->gtt_mappable_entries);
+	if ((dev_priv->gtt.mappable_end < (64<<20) ||
+	    (dev_priv->gtt.mappable_end > (512<<20)))) {
+		DRM_ERROR("Unknown GMADR size (%lx)\n",
+			  dev_priv->gtt.mappable_end);
 		ret = -ENXIO;
 		goto err_out;
 	}
@@ -759,7 +758,7 @@ int i915_gem_gtt_init(struct drm_device *dev)
 
 	/* GMADR is the PCI aperture used by SW to access tiled GFX surfaces in a linear fashion. */
 	DRM_INFO("Memory usable by graphics device = %dM\n", dev_priv->mm.gtt->gtt_total_entries >> 8);
-	DRM_DEBUG_DRIVER("GMADR size = %dM\n", dev_priv->mm.gtt->gtt_mappable_entries >> 8);
+	DRM_DEBUG_DRIVER("GMADR size = %ldM\n", dev_priv->gtt.mappable_end >> 20);
 	DRM_DEBUG_DRIVER("GTT stolen size = %dM\n", dev_priv->mm.gtt->stolen_size >> 20);
 
 	return 0;
diff --git a/drivers/gpu/drm/i915/intel_fb.c b/drivers/gpu/drm/i915/intel_fb.c
index ce02af8..ce5f544 100644
--- a/drivers/gpu/drm/i915/intel_fb.c
+++ b/drivers/gpu/drm/i915/intel_fb.c
@@ -135,8 +135,7 @@ static int intelfb_create(struct intel_fbdev *ifbdev,
 		goto out_unpin;
 	}
 	info->apertures->ranges[0].base = dev->mode_config.fb_base;
-	info->apertures->ranges[0].size =
-		dev_priv->mm.gtt->gtt_mappable_entries << PAGE_SHIFT;
+	info->apertures->ranges[0].size = dev_priv->gtt.mappable_end;
 
 	info->fix.smem_start = dev->mode_config.fb_base + obj->gtt_offset;
 	info->fix.smem_len = size;
-- 
1.8.1