As the previous punit i/o may have failed, the contents of the PDATA are undefined. Always clear it to 0 prior to sending the command.
Signed-off-by: Chris Wilson <[email protected]> Cc: Mika Kuoppala <[email protected]> --- drivers/gpu/drm/i915/intel_sideband.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_sideband.c b/drivers/gpu/drm/i915/intel_sideband.c index d3d49a09c919..9f782b5eb6e6 100644 --- a/drivers/gpu/drm/i915/intel_sideband.c +++ b/drivers/gpu/drm/i915/intel_sideband.c @@ -60,8 +60,7 @@ static int vlv_sideband_rw(struct drm_i915_private *dev_priv, u32 devfn, } I915_WRITE(VLV_IOSF_ADDR, addr); - if (!is_read) - I915_WRITE(VLV_IOSF_DATA, *val); + I915_WRITE(VLV_IOSF_DATA, is_read ? 0 : *val); I915_WRITE(VLV_IOSF_DOORBELL_REQ, cmd); if (intel_wait_for_register(dev_priv, @@ -74,7 +73,6 @@ static int vlv_sideband_rw(struct drm_i915_private *dev_priv, u32 devfn, if (is_read) *val = I915_READ(VLV_IOSF_DATA); - I915_WRITE(VLV_IOSF_DATA, 0); return 0; } -- 2.11.0 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
