linux-arm.git - Russell King's ARM Linux kernel tree

Age	Commit message (Collapse)	Author
2022-02-25	drm/i915/gt: Add helper for shmem copy to iosys_map	Lucas De Marchi
	Add a variant of shmem_read() that takes a iosys_map pointer rather than a plain pointer as argument. It's mostly a copy __shmem_rw() but adapting the api and removing the write support since there's currently only need to use iosys_map as destination. Reworking __shmem_rw() to share the implementation was tempting, but finding a good balance between reuse and clarity pushed towards a little code duplication. Since the function is small, just add the similar function with a copy/paste/adapt approach. v2: Add an offset as argument and instead of using a map iterator, use the offset to keep track of where we are writing data to. Cc: Matt Roper <matthew.d.roper@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220216174147.3073235-4-lucas.demarchi@intel.com
2020-04-29	drm/i915/gt: Keep a no-frills swappable copy of the default context state	Chris Wilson
	We need to keep the default context state around to instantiate new contexts (aka golden rendercontext), and we also keep it pinned while the engine is active so that we can quickly reset a hanging context. However, the default contexts are large enough to merit keeping in swappable memory as opposed to kernel memory, so we store them inside shmemfs. Currently, we use the normal GEM objects to create the default context image, but we can throw away all but the shmemfs file. This greatly simplifies the tricky power management code which wants to run underneath the normal GT locking, and we definitely do not want to use any high level objects that may appear to recurse back into the GT. Though perhaps the primary advantage of the complex GEM object is that we aggressively cache the mapping, but here we are recreating the vm_area everytime time we unpark. At the worst, we add a lightweight cache, but first find a microbenchmark that is impacted. Having started to create some utility functions to make working with shmemfs objects easier, we can start putting them to wider use, where GEM objects are overkill, such as storing persistent error state. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Matthew Auld <matthew.auld@intel.com> Cc: Ramalingam C <ramalingam.c@intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Reviewed-by: Matthew Auld <matthew.auld@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200429172429.6054-1-chris@chris-wilson.co.uk