linux/drivers/gpu
Imre Deak 5fbc2c2bfa drm/i915/gem: Add a helper to read data from a GEM object page
Add a simple helper to read data with the CPU from the page of a GEM
object. Do the read either via a kmap if the object has struct pages
or an iomap otherwise. This is needed by the next patch, reading a u64
value from the object (w/o requiring the obj to be mapped to the GPU).

Suggested by Chris.

v2 (Chris):
- Sanitize the type and order of func params.
- Avoid consts requiring too many casts.
- Use BUG_ON instead of WARN_ON, simplify the conditions.
- Fix __iomem sparse errors.
- Leave locking/syncing/pinning up to the caller, require only that the
  caller has pinned the object pages.
- Check for iomem backing store before reading via an iomap.
v3:
- Fix offset passed to io_mapping_map_wc() missing a mem.region.start
  delta. (Chris, Matthew)

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20210120213834.1435710-1-imre.deak@intel.com
2021-01-22 15:59:35 +02:00
..
drm drm/i915/gem: Add a helper to read data from a GEM object page 2021-01-22 15:59:35 +02:00
host1x gpu/host1x: bus: Add missing description for 'driver' 2020-11-05 22:12:55 +01:00
ipu-v3 gpu/ipu-v3/ipu-di: Strip out 2 unused 'di_sync_config' entries 2021-01-04 12:54:18 +01:00
trace
vga pci-v5.11-changes 2020-12-15 16:49:59 -08:00
Makefile