drm/msm: add support for "stolen" mem
Add support to use the VRAM carveout (if specified in dtb) for fbdev
scanout buffer. This allows drm/msm to take over a bootloader splash-
screen, and avoids corruption on screen that results if the kernel uses
memory that is still being scanned out for itself.
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
index 49dea4f..479d8af 100644
--- a/drivers/gpu/drm/msm/msm_gem.c
+++ b/drivers/gpu/drm/msm/msm_gem.c
@@ -32,6 +32,12 @@
priv->vram.paddr;
}
+static bool use_pages(struct drm_gem_object *obj)
+{
+ struct msm_gem_object *msm_obj = to_msm_bo(obj);
+ return !msm_obj->vram_node;
+}
+
/* allocate pages from VRAM carveout, used when no IOMMU: */
static struct page **get_pages_vram(struct drm_gem_object *obj,
int npages)
@@ -72,7 +78,7 @@
struct page **p;
int npages = obj->size >> PAGE_SHIFT;
- if (iommu_present(&platform_bus_type))
+ if (use_pages(obj))
p = drm_gem_get_pages(obj);
else
p = get_pages_vram(obj, npages);
@@ -116,7 +122,7 @@
sg_free_table(msm_obj->sgt);
kfree(msm_obj->sgt);
- if (iommu_present(&platform_bus_type))
+ if (use_pages(obj))
drm_gem_put_pages(obj, msm_obj->pages, true, false);
else {
drm_mm_remove_node(msm_obj->vram_node);
@@ -580,6 +586,7 @@
struct msm_drm_private *priv = dev->dev_private;
struct msm_gem_object *msm_obj;
unsigned sz;
+ bool use_vram = false;
switch (flags & MSM_BO_CACHE_MASK) {
case MSM_BO_UNCACHED:
@@ -592,15 +599,23 @@
return -EINVAL;
}
- sz = sizeof(*msm_obj);
if (!iommu_present(&platform_bus_type))
+ use_vram = true;
+ else if ((flags & MSM_BO_STOLEN) && priv->vram.size)
+ use_vram = true;
+
+ if (WARN_ON(use_vram && !priv->vram.size))
+ return -EINVAL;
+
+ sz = sizeof(*msm_obj);
+ if (use_vram)
sz += sizeof(struct drm_mm_node);
msm_obj = kzalloc(sz, GFP_KERNEL);
if (!msm_obj)
return -ENOMEM;
- if (!iommu_present(&platform_bus_type))
+ if (use_vram)
msm_obj->vram_node = (void *)&msm_obj[1];
msm_obj->flags = flags;
@@ -630,7 +645,7 @@
if (ret)
goto fail;
- if (iommu_present(&platform_bus_type)) {
+ if (use_pages(obj)) {
ret = drm_gem_object_init(dev, obj, size);
if (ret)
goto fail;