dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

staging: drm/omap: mmap of tiled buffers with stride >4kb 

Deal with the case of buffers with virtual stride larger than one
page in fault_2d().

Signed-off-by: Rob Clark <rob@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rob Clark 2012-03-05 10:48:40 -06:00 committed by Greg Kroah-Hartman
parent 5c13779737
commit e559895ae9
1 changed files with 58 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

84
drivers/staging/omapdrm/omap_gem.c
View File

@ -153,10 +153,23 @@ static void evict_entry(struct drm_gem_object *obj,
enum tiler_fmt fmt, struct usergart_entry *entry)
{
if (obj->dev->dev_mapping) {
size_t size = PAGE_SIZE * usergart[fmt].height;
struct omap_gem_object *omap_obj = to_omap_bo(obj);
int n = usergart[fmt].height;
size_t size = PAGE_SIZE * n;
loff_t off = mmap_offset(obj) +
(entry->obj_pgoff << PAGE_SHIFT);
unmap_mapping_range(obj->dev->dev_mapping, off, size, 1);
const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE);
if (m > 1) {
int i;
/* if stride > than PAGE_SIZE then sparse mapping: */
for (i = n; i > 0; i--) {
unmap_mapping_range(obj->dev->dev_mapping,
off, PAGE_SIZE, 1);
off += PAGE_SIZE * m;
}
} else {
unmap_mapping_range(obj->dev->dev_mapping, off, size, 1);
}
}
entry->obj = NULL;
@ -342,26 +355,39 @@ static int fault_2d(struct drm_gem_object *obj,
void __user *vaddr;
int i, ret, slots;
if (!usergart)
return -EFAULT;
/* TODO: this fxn might need a bit tweaking to deal w/ tiled buffers
* that are wider than 4kb
/*
* Note the height of the slot is also equal to the number of pages
* that need to be mapped in to fill 4kb wide CPU page. If the slot
* height is 64, then 64 pages fill a 4kb wide by 64 row region.
*/
const int n = usergart[fmt].height;
const int n_shift = usergart[fmt].height_shift;
/*
* If buffer width in bytes > PAGE_SIZE then the virtual stride is
* rounded up to next multiple of PAGE_SIZE.. this need to be taken
* into account in some of the math, so figure out virtual stride
* in pages
*/
const int m = 1 + ((omap_obj->width << fmt) / PAGE_SIZE);
/* We don't use vmf->pgoff since that has the fake offset: */
pgoff = ((unsigned long)vmf->virtual_address -
vma->vm_start) >> PAGE_SHIFT;
/* actual address we start mapping at is rounded down to previous slot
/*
* Actual address we start mapping at is rounded down to previous slot
* boundary in the y direction:
*/
base_pgoff = round_down(pgoff, usergart[fmt].height);
vaddr = vmf->virtual_address - ((pgoff - base_pgoff) << PAGE_SHIFT);
entry = &usergart[fmt].entry[usergart[fmt].last];
base_pgoff = round_down(pgoff, m << n_shift);
/* figure out buffer width in slots */
slots = omap_obj->width >> usergart[fmt].slot_shift;
vaddr = vmf->virtual_address - ((pgoff - base_pgoff) << PAGE_SHIFT);
entry = &usergart[fmt].entry[usergart[fmt].last];
/* evict previous buffer using this usergart entry, if any: */
if (entry->obj)
evict_entry(entry->obj, fmt, entry);
@ -369,23 +395,30 @@ static int fault_2d(struct drm_gem_object *obj,
entry->obj = obj;
entry->obj_pgoff = base_pgoff;
/* now convert base_pgoff to phys offset from virt offset:
*/
base_pgoff = (base_pgoff >> usergart[fmt].height_shift) * slots;
/* now convert base_pgoff to phys offset from virt offset: */
base_pgoff = (base_pgoff >> n_shift) * slots;
/* map in pages. Note the height of the slot is also equal to the
* number of pages that need to be mapped in to fill 4kb wide CPU page.
* If the height is 64, then 64 pages fill a 4kb wide by 64 row region.
* Beyond the valid pixel part of the buffer, we set pages[i] to NULL to
* get a dummy page mapped in.. if someone reads/writes it they will get
* random/undefined content, but at least it won't be corrupting
* whatever other random page used to be mapped in, or other undefined
* behavior.
/* for wider-than 4k.. figure out which part of the slot-row we want: */
if (m > 1) {
int off = pgoff % m;
entry->obj_pgoff += off;
base_pgoff /= m;
slots = min(slots - (off << n_shift), n);
base_pgoff += off << n_shift;
vaddr += off << PAGE_SHIFT;
}
/*
* Map in pages. Beyond the valid pixel part of the buffer, we set
* pages[i] to NULL to get a dummy page mapped in.. if someone
* reads/writes it they will get random/undefined content, but at
* least it won't be corrupting whatever other random page used to
* be mapped in, or other undefined behavior.
*/
memcpy(pages, &omap_obj->pages[base_pgoff],
sizeof(struct page *) * slots);
memset(pages + slots, 0,
sizeof(struct page *) * (usergart[fmt].height - slots));
sizeof(struct page *) * (n - slots));
ret = tiler_pin(entry->block, pages, ARRAY_SIZE(pages), 0, true);
if (ret) {
@ -393,16 +426,15 @@ static int fault_2d(struct drm_gem_object *obj,
return ret;
}
i = usergart[fmt].height;
pfn = entry->paddr >> PAGE_SHIFT;
VERB("Inserting %p pfn %lx, pa %lx", vmf->virtual_address,
pfn, pfn << PAGE_SHIFT);
while (i--) {
for (i = n; i > 0; i--) {
vm_insert_mixed(vma, (unsigned long)vaddr, pfn);
pfn += usergart[fmt].stride_pfn;
vaddr += PAGE_SIZE;
vaddr += PAGE_SIZE * m;
}
/* simple round-robin: */