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| author |   Michal Wajdeczko <michal.wajdeczko@intel.com> | 2017-04-10 12:17:47 +0000 |
|---|---|---|
| committer |   Chris Wilson <chris@chris-wilson.co.uk> | 2017-04-10 15:24:52 +0100 |
| commit | 6976e74b5fa12430b36c3b0f8afd7e8e695be0ab (patch) | |
| tree | 1946989cff548bbacab98eb1f850da75c33f4085 /drivers/gpu/drm/i915/intel_uncore.c | |
| parent | drm/i915: Drop const qualifiers from params in wait_for_register() (diff) | |
| download | linux-dev-6976e74b5fa12430b36c3b0f8afd7e8e695be0ab.tar.xz linux-dev-6976e74b5fa12430b36c3b0f8afd7e8e695be0ab.zip | |
drm/i915: Don't allow overuse of __intel_wait_for_register_fw()
This function should not be called with long timeouts in atomic context.
Annotate it as might_sleep if timeout is longer than 10us.
v2: fix comment (Michal)
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170410121747.209200-1-michal.wajdeczko@intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Diffstat (limited to 'drivers/gpu/drm/i915/intel_uncore.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_uncore.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c index 1deb1a4342ba..eb38392a2435 100644 --- a/drivers/gpu/drm/i915/intel_uncore.c +++ b/drivers/gpu/drm/i915/intel_uncore.c @@ -1600,6 +1600,8 @@ static int gen6_reset_engines(struct drm_i915_private *dev_priv, * (I915_READ_FW(reg) & mask) == value * * Otherwise, the wait will timeout after @slow_timeout_ms milliseconds. + * For atomic context @slow_timeout_ms must be zero and @fast_timeout_us + * must be not larger than 10 microseconds. * * Note that this routine assumes the caller holds forcewake asserted, it is * not suitable for very long waits. See intel_wait_for_register() if you @@ -1620,6 +1622,9 @@ int __intel_wait_for_register_fw(struct drm_i915_private *dev_priv, #define done (((reg_value = I915_READ_FW(reg)) & mask) == value) int ret; + /* Catch any overuse of this function */ + might_sleep_if(fast_timeout_us > 10 || slow_timeout_ms); + if (fast_timeout_us > 10) ret = _wait_for(done, fast_timeout_us, 10); else |