From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Widawsky Subject: [PATCH] drm/i915: Correct sandybrige overclocking Date: Tue, 19 Mar 2013 20:19:56 -0700 Message-ID: <1363749596-1429-1-git-send-email-ben@bwidawsk.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from shiva.localdomain (209-20-75-48.static.cloud-ips.com [209.20.75.48]) by gabe.freedesktop.org (Postfix) with ESMTP id E4EA0E5D14 for ; Tue, 19 Mar 2013 20:18:12 -0700 (PDT) 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: Ben Widawsky List-Id: intel-gfx@lists.freedesktop.org Change the gen6+ max delay if the pcode read was successful (not the inverse). The previous code was all sorts of wrong and has existed since I broke it: commit 42c0526c930523425ff6edc95b7235ce7ab9308d Author: Ben Widawsky Date: Wed Sep 26 10:34:00 2012 -0700 drm/i915: Extract PCU communication I added some parentheses for clarity, and I also corrected the debug message message to use the mask (wrong before I came along) and added a print to show the value we're changing from. Looking over the code, I'm not actually sure what we're trying to do. I introduced the bug simply by extracting the function not implementing anything new. We already set max_delay based on the capabilities register (which is what we use elsewhere to determine min and max). This would potentially increase it, I suppose? Jesse, I can't find the document which explains the definitions of the pcode commands, maybe you have it around. Based on Jesse's response, this could potentially be for -fixes, or stable, or maybe lead to us dropping it entirely. As the current code is is, things won't completely break because of the aforementioned capabilities register, and in my experimentation, enabling this has no effect, it goes from 1100->1100. I found this while reviewing Jesse's VLV patches. Cc: Jesse Barnes Signed-off-by: Ben Widawsky --- drivers/gpu/drm/i915/intel_pm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index c30e89a..86729b1 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2631,9 +2631,11 @@ static void gen6_enable_rps(struct drm_device *dev) if (!ret) { pcu_mbox = 0; ret = sandybridge_pcode_read(dev_priv, GEN6_READ_OC_PARAMS, &pcu_mbox); - if (ret && pcu_mbox & (1<<31)) { /* OC supported */ + if (!ret && (pcu_mbox & (1<<31))) { /* OC supported */ + DRM_DEBUG_DRIVER("overclocking supported, adjusting frequency max from %dMHz to %dMHz\n", + ((dev_priv->rps.max_delay & 0xff) * 50), + ((pcu_mbox & 0xff) * 50)); dev_priv->rps.max_delay = pcu_mbox & 0xff; - DRM_DEBUG_DRIVER("overclocking supported, adjusting frequency max to %dMHz\n", pcu_mbox * 50); } } else { DRM_DEBUG_DRIVER("Failed to set the min frequency\n"); -- 1.8.2