From 862372bc8fefb7bdc243dd120448b970244c8185 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Wed, 12 Oct 2016 14:44:47 +0300 Subject: [PATCH] drm/i915: GMBUS don't need no forcewake MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit GMBUS is part of the display engine, and thus has no need for forcewake. Let's not bother trying to grab it then. I don't recall if the display engine suffers from system hangs due to multiple accesses to the same "cacheline" in mmio space. I hope not since we're no longer protected by the uncore lock since commit 4e6c2d58ba86 ("drm/i915: Take forcewake once for the entire GMBUS transaction") Cc: Chris Wilson Cc: David Weinehall Signed-off-by: Ville Syrjälä Link: http://patchwork.freedesktop.org/patch/msgid/1476272687-15070-1-git-send-email-ville.syrjala@linux.intel.com Reviewed-by: Chris Wilson --- drivers/gpu/drm/i915/intel_i2c.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c index d04185e1edd6..83f260bb4eef 100644 --- a/drivers/gpu/drm/i915/intel_i2c.c +++ b/drivers/gpu/drm/i915/intel_i2c.c @@ -467,13 +467,9 @@ do_gmbus_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) struct intel_gmbus, adapter); struct drm_i915_private *dev_priv = bus->dev_priv; - const unsigned int fw = - intel_uncore_forcewake_for_reg(dev_priv, GMBUS0, - FW_REG_READ | FW_REG_WRITE); int i = 0, inc, try = 0; int ret = 0; - intel_uncore_forcewake_get(dev_priv, fw); retry: I915_WRITE_FW(GMBUS0, bus->reg0); @@ -575,7 +571,6 @@ timeout: ret = -EAGAIN; out: - intel_uncore_forcewake_put(dev_priv, fw); return ret; } -- 2.20.1