From b1f9415bf355e9fbd6fc3ce8fa1af59083ca2943 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 26 Jan 2012 13:59:24 +0000
Subject: [PATCH] sna: Allow gen4+ to use larger GPU bo

As the blitter on gen4+ does not require fence registers, it is not
restricted to operating on large objects within the mappable aperture.
As we do not need to operate on such large GPU bo in place, we can relax
the restriction on the maximum bo size for gen4+ to allocate for use
with the GPU.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 src/sna/kgem.c | 21 +++++++++++++++------
 src/sna/kgem.h |  6 ++++++
 2 files changed, 21 insertions(+), 6 deletions(-)

diff --git a/src/sna/kgem.c b/src/sna/kgem.c
index 6cd86e6f..4df29d2f 100644
--- a/src/sna/kgem.c
+++ b/src/sna/kgem.c
@@ -658,15 +658,22 @@ void kgem_init(struct kgem *kgem, int fd, struct pci_device *dev, int gen)
 		 * disable dual-stream mode */
 		kgem->min_alignment = 64;
 
-	kgem->max_gpu_size = kgem->aperture_mappable / 2;
-	if (kgem->max_gpu_size > kgem->aperture_low)
-		kgem->max_gpu_size = kgem->aperture_low;
-	if (kgem->max_gpu_size > MAX_OBJECT_SIZE)
-		kgem->max_gpu_size = MAX_OBJECT_SIZE;
-
 	kgem->max_cpu_size = kgem->aperture_total / 2;
 	if (kgem->max_cpu_size > MAX_OBJECT_SIZE)
 		kgem->max_cpu_size = MAX_OBJECT_SIZE;
+
+	kgem->max_gpu_size = -1;
+	if (gen < 40) {
+		/* If we have to use fences for blitting, we have to make
+		 * sure we can fit them into the aperture.
+		 */
+		kgem->max_gpu_size = kgem->aperture_mappable / 2;
+		if (kgem->max_gpu_size > kgem->aperture_low)
+			kgem->max_gpu_size = kgem->aperture_low;
+	}
+	if (kgem->max_gpu_size > kgem->max_cpu_size)
+		kgem->max_gpu_size = kgem->max_cpu_size;
+
 	DBG(("%s: max object size (tiled=%d, linear=%d)\n",
 	     __FUNCTION__, kgem->max_gpu_size, kgem->max_cpu_size));
 
@@ -2729,6 +2736,8 @@ void *kgem_bo_map(struct kgem *kgem, struct kgem_bo *bo)
 
 	ptr = bo->map;
 	if (ptr == NULL) {
+		assert(bo->size <= kgem->aperture_mappable / 4);
+
 		kgem_trim_vma_cache(kgem, MAP_GTT, bo->bucket);
 
 		ptr = gem_mmap(kgem->fd, bo->handle, bo->size,
diff --git a/src/sna/kgem.h b/src/sna/kgem.h
index 0cc4fd3b..0dc67dac 100644
--- a/src/sna/kgem.h
+++ b/src/sna/kgem.h
@@ -363,10 +363,16 @@ static inline bool kgem_bo_is_mappable(struct kgem *kgem,
 	if (bo->domain == DOMAIN_GTT)
 		return true;
 
+	if (IS_GTT_MAP(bo->map))
+		return true;
+
 	if (kgem->gen < 40 && bo->tiling &&
 	    bo->presumed_offset & (kgem_bo_fenced_size(kgem, bo) - 1))
 		return false;
 
+	if (!bo->presumed_offset)
+		return bo->size <= kgem->aperture_mappable / 4;
+
 	return bo->presumed_offset + bo->size <= kgem->aperture_mappable;
 }