diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-07-09 14:44:26 +0200 |
---|---|---|
committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2013-07-09 16:52:19 +0200 |
commit | 36c0cc616e518bfc2b685bed7fb3243d1242eca4 (patch) | |
tree | 60e7d5b077dc74d9316089a5cb84b20df8d26a58 /drivers/gpu/drm/i915/i915_drv.c | |
parent | eaba1b8f3379b5d100bd146b9a41d28348bdfd09 (diff) |
drm/i915: clean up media reset on gm45
Originally I've thought that this fixes up the reset issues on my
gm45, but that was just a red herring due to b0rked testing.
Still I much prefer writing the right values (all other fields are
reserved) instead of potentially dragging gunk around. Hence also
clear the register to 0 after a reset.
Note that Cspec is a bit confused and doesn't explicitly say that all
the other bits in this register are "reserved, mbz" like usually.
Instead they're marked as "r/o, default value = 0" which semantically
amounts to the same thing.
v2: Stop claiming this fixes anything and return 0 if successful
instead of stack garbage.
v3: Pimp the commit message to explain exactly why I think the docs
allow us to ditch the rmw cycle, spurred by a discussion with Chris.
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_drv.c')
-rw-r--r-- | drivers/gpu/drm/i915/i915_drv.c | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 33cb97388fc9..ed9262c42b7b 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -798,28 +798,29 @@ static int i965_reset_complete(struct drm_device *dev) static int i965_do_reset(struct drm_device *dev) { int ret; - u8 gdrst; /* * Set the domains we want to reset (GRDOM/bits 2 and 3) as * well as the reset bit (GR/bit 0). Setting the GR bit * triggers the reset; when done, the hardware will clear it. */ - pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst); pci_write_config_byte(dev->pdev, I965_GDRST, - gdrst | GRDOM_RENDER | - GRDOM_RESET_ENABLE); + GRDOM_RENDER | GRDOM_RESET_ENABLE); ret = wait_for(i965_reset_complete(dev), 500); if (ret) return ret; /* We can't reset render&media without also resetting display ... */ - pci_read_config_byte(dev->pdev, I965_GDRST, &gdrst); pci_write_config_byte(dev->pdev, I965_GDRST, - gdrst | GRDOM_MEDIA | - GRDOM_RESET_ENABLE); + GRDOM_MEDIA | GRDOM_RESET_ENABLE); - return wait_for(i965_reset_complete(dev), 500); + ret = wait_for(i965_reset_complete(dev), 500); + if (ret) + return ret; + + pci_write_config_byte(dev->pdev, I965_GDRST, 0); + + return 0; } static int ironlake_do_reset(struct drm_device *dev) |