From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paulo Zanoni Subject: [PATCH 4/8] drm/i915: avoid waking up from PC8 on DP AUX operations Date: Mon, 29 Jul 2013 17:48:23 -0300 Message-ID: <1375130907-4054-5-git-send-email-przanoni@gmail.com> References: <1375130907-4054-1-git-send-email-przanoni@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-gg0-f170.google.com (mail-gg0-f170.google.com [209.85.161.170]) by gabe.freedesktop.org (Postfix) with ESMTP id 63422E60F9 for ; Mon, 29 Jul 2013 13:48:57 -0700 (PDT) Received: by mail-gg0-f170.google.com with SMTP id f4so256404ggn.29 for ; Mon, 29 Jul 2013 13:48:56 -0700 (PDT) In-Reply-To: <1375130907-4054-1-git-send-email-przanoni@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: intel-gfx@lists.freedesktop.org Cc: Paulo Zanoni List-Id: intel-gfx@lists.freedesktop.org From: Paulo Zanoni If we're already allowing PC8, just don't use the IRQs, so we won't need to wake from PC8. Waking up from PC8 is a slow thing, so avoid it when we can. Signed-off-by: Paulo Zanoni --- drivers/gpu/drm/i915/intel_dp.c | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index a531912..88ccbd5 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -315,6 +315,24 @@ static uint32_t get_aux_clock_divider(struct intel_dp *intel_dp, } } +static bool intel_dp_use_aux_irq(struct drm_device *dev) +{ + struct drm_i915_private *dev_priv = dev->dev_private; + bool ret; + + if (INTEL_INFO(dev)->gen <= 4 || IS_VALLEYVIEW(dev)) + return false; + + /* In case we're already allowing PC8, just don't use IRQs, so we won't + * need to call intel_aux_display_runtime_get and then we won't wake up + * from PC8. */ + mutex_lock(&dev_priv->pc8.lock); + ret = (dev_priv->pc8.forbid_refcnt != 0); + mutex_unlock(&dev_priv->pc8.lock); + + return ret; +} + static int intel_dp_aux_ch(struct intel_dp *intel_dp, uint8_t *send, int send_bytes, @@ -329,7 +347,7 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, int i, ret, recv_bytes; uint32_t status; int try, precharge, clock = 0; - bool has_aux_irq = INTEL_INFO(dev)->gen >= 5 && !IS_VALLEYVIEW(dev); + bool has_aux_irq = intel_dp_use_aux_irq(dev); /* dp aux is extremely sensitive to irq latency, hence request the * lowest possible wakeup latency and so prevent the cpu from going into @@ -344,7 +362,8 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, else precharge = 5; - intel_aux_display_runtime_get(dev_priv); + if (has_aux_irq) + intel_aux_display_runtime_get(dev_priv); /* Try to wait for any previous AUX channel activity */ for (try = 0; try < 3; try++) { @@ -436,7 +455,8 @@ intel_dp_aux_ch(struct intel_dp *intel_dp, ret = recv_bytes; out: pm_qos_update_request(&dev_priv->pm_qos, PM_QOS_DEFAULT_VALUE); - intel_aux_display_runtime_put(dev_priv); + if (has_aux_irq) + intel_aux_display_runtime_put(dev_priv); return ret; } -- 1.8.1.2