Commit Graph

5 Commits

Author SHA1 Message Date
Jordan Crouse
88b333b0ed drm/msm: Ensure that the hardware write pointer is valid
Currently the value written to CP_RB_WPTR is calculated on the fly as
(rb->next - rb->start). But as the code is designed rb->next is wrapped
before writing the commands so if a series of commands happened to
fit perfectly in the ringbuffer, rb->next would end up being equal to
rb->size / 4 and thus result in an out of bounds address to CP_RB_WPTR.

The easiest way to fix this is to mask WPTR when writing it to the
hardware; it makes the hardware happy and the rest of the ringbuffer
math appears to work and there isn't any point in upsetting anything.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
[squash in is_power_of_2() check]
Signed-off-by: Rob Clark <robdclark@gmail.com>
2016-12-29 15:02:58 -05:00
Rob Clark
18f23049f6 drm/msm: change gem->vmap() to get/put
Before we can add vmap shrinking, we really need to know which vmap'ings
are currently being used.  So switch to get/put interface.  Stubbed put
fxns for now.

Signed-off-by: Rob Clark <robdclark@gmail.com>
2016-07-16 10:09:07 -04:00
Rob Clark
69a834c28f drm/msm: deal with exhausted vmap space better
Some, but not all, callers of obj->vmap() would check if return
IS_ERR().  So let's actually return an error if vmap() fails.  And fixup
the call-sites that were not handling this properly.

Signed-off-by: Rob Clark <robdclark@gmail.com>
2016-06-04 14:45:48 -04:00
Rob Clark
774449ebcb drm/msm: fix locking inconsistencies in gpu->destroy()
In error paths, this was being called without struct_mutex held.
Leading to panics like:

  msm 1a00000.qcom,mdss_mdp: No memory protection without IOMMU
  Kernel panic - not syncing: BUG!
  CPU: 0 PID: 1409 Comm: cat Not tainted 4.0.0-dirty #4
  Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
  Call trace:
  [<ffffffc000089c78>] dump_backtrace+0x0/0x118
  [<ffffffc000089da0>] show_stack+0x10/0x20
  [<ffffffc0006686d4>] dump_stack+0x84/0xc4
  [<ffffffc0006678b4>] panic+0xd0/0x210
  [<ffffffc0003e1ce4>] drm_gem_object_free+0x5c/0x60
  [<ffffffc000402870>] adreno_gpu_cleanup+0x60/0x80
  [<ffffffc0004035a0>] a3xx_destroy+0x20/0x70
  [<ffffffc0004036f4>] a3xx_gpu_init+0x84/0x108
  [<ffffffc0004018b8>] adreno_load_gpu+0x58/0x190
  [<ffffffc000419dac>] msm_open+0x74/0x88
  [<ffffffc0003e0a48>] drm_open+0x168/0x400
  [<ffffffc0003e7210>] drm_stub_open+0xa8/0x118
  [<ffffffc0001a0e84>] chrdev_open+0x94/0x198
  [<ffffffc000199f88>] do_dentry_open+0x208/0x310
  [<ffffffc00019a4c4>] vfs_open+0x44/0x50
  [<ffffffc0001aa26c>] do_last.isra.14+0x2c4/0xc10
  [<ffffffc0001aac38>] path_openat+0x80/0x5e8
  [<ffffffc0001ac354>] do_filp_open+0x2c/0x98
  [<ffffffc00019b60c>] do_sys_open+0x13c/0x228
  [<ffffffc00019b72c>] SyS_openat+0xc/0x18
  CPU1: stopping

But there isn't any particularly good reason to hold struct_mutex for
teardown, so just standardize on calling it without the mutex held and
use the _unlocked() versions for GEM obj unref'ing

Signed-off-by: Rob Clark <robdclark@gmail.com>
2015-05-15 09:28:27 -04:00
Rob Clark
7198e6b031 drm/msm: add a3xx gpu support
Add initial support for a3xx 3d core.

So far, with hardware that I've seen to date, we can have:
 + zero, one, or two z180 2d cores
 + a3xx or a2xx 3d core, which share a common CP (the firmware
   for the CP seems to implement some different PM4 packet types
   but the basics of cmdstream submission are the same)

Which means that the eventual complete "class" hierarchy, once
support for all past and present hw is in place, becomes:
 + msm_gpu
   + adreno_gpu
     + a3xx_gpu
     + a2xx_gpu
   + z180_gpu

This commit splits out the parts that will eventually be common
between a2xx/a3xx into adreno_gpu, and the parts that are even
common to z180 into msm_gpu.

Note that there is no cmdstream validation required.  All memory access
from the GPU is via IOMMU/MMU.  So as long as you don't map silly things
to the GPU, there isn't much damage that the GPU can do.

Signed-off-by: Rob Clark <robdclark@gmail.com>
2013-08-24 14:57:18 -04:00