From patchwork Fri May 1 18:25:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jordan Crouse X-Patchwork-Id: 11523137 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D3FB992C for ; Fri, 1 May 2020 18:26:12 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B23ED24961 for ; Fri, 1 May 2020 18:26:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="doYEpmF7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B23ED24961 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 8448B6ED32; Fri, 1 May 2020 18:26:08 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from mail27.static.mailgun.info (mail27.static.mailgun.info [104.130.122.27]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8A2856ED32 for ; Fri, 1 May 2020 18:26:01 +0000 (UTC) DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1588357566; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=oAbv7Whc5wnDq0DJoREo5UCU2XgDlITRPhApd/IgUDo=; b=doYEpmF7x2b/qo2iOrdCM3WEhtC+4HkIXmR9Tqt4Gfu/jdMtlyhJ+Xgd0QGoKXiJAI7XtY/w TLnxGcZm8Q/8pvF17PSnNNip8edF+ahqnxDJfHvErtzQr+nXHAyMXUErZZs+1jXu8NKiNIh4 OXxKTwaWlF8A0TPZFxCo76psxs8= X-Mailgun-Sending-Ip: 104.130.122.27 X-Mailgun-Sid: WyJkOTU5ZSIsICJkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by mxa.mailgun.org with ESMTP id 5eac69b1.7f7d8f25dc70-smtp-out-n02; Fri, 01 May 2020 18:25:53 -0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 1001) id F4115C43636; Fri, 1 May 2020 18:25:50 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=2.0 tests=ALL_TRUSTED,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.0 Received: from jordan-laptop.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: jcrouse) by smtp.codeaurora.org (Postfix) with ESMTPSA id 28E29C433D2; Fri, 1 May 2020 18:25:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 28E29C433D2 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=jcrouse@codeaurora.org From: Jordan Crouse To: linux-arm-msm@vger.kernel.org Subject: [PATCH] drm/msm: Check for powered down HW in the devfreq callbacks Date: Fri, 1 May 2020 12:25:33 -0600 Message-Id: <20200501182533.19753-1-jcrouse@codeaurora.org> X-Mailer: git-send-email 2.17.1 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jeffrey Hugo , David Airlie , freedreno@lists.freedesktop.org, Sharat Masetty , Akhil P Oommen , stable@vger.kernel.org, Stephen Boyd , Ben Dooks , dri-devel@lists.freedesktop.org, Thomas Gleixner , AngeloGioacchino Del Regno , Sean Paul , linux-kernel@vger.kernel.org MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Writing to the devfreq sysfs nodes while the GPU is powered down can result in a system crash (on a5xx) or a nasty GMU error (on a6xx): $ /sys/class/devfreq/5000000.gpu# echo 500000000 > min_freq [ 104.841625] platform 506a000.gmu: [drm:a6xx_gmu_set_oob] *ERROR* Timeout waiting for GMU OOB set GPU_DCVS: 0x0 Despite the fact that we carefully try to suspend the devfreq device when the hardware is powered down there are lots of holes in the governors that don't check for the suspend state and blindly call into the devfreq callbacks that end up triggering hardware reads in the GPU driver. Check the power state in the gpu_busy() and gpu_set_freq() callbacks for a5xx and a6xx to make sure that the hardware is active before trying to access it. Cc: stable@vger.kernel.org Signed-off-by: Jordan Crouse --- drivers/gpu/drm/msm/adreno/a5xx_gpu.c | 4 ++++ drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 4 ++++ drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 4 ++++ 3 files changed, 12 insertions(+) diff --git a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c index 724024a2243a..9d8c7fe6377e 100644 --- a/drivers/gpu/drm/msm/adreno/a5xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a5xx_gpu.c @@ -1404,6 +1404,10 @@ static unsigned long a5xx_gpu_busy(struct msm_gpu *gpu) { u64 busy_cycles, busy_time; + /* devfreq can get here while we are idle so do a quick check first */ + if (!pm_runtime_active(&gpu->pdev->dev)) + return ~0LU; + busy_cycles = gpu_read64(gpu, REG_A5XX_RBBM_PERFCTR_RBBM_0_LO, REG_A5XX_RBBM_PERFCTR_RBBM_0_HI); diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c index c4e71abbdd53..84618f2ff073 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c @@ -108,6 +108,10 @@ static void __a6xx_gmu_set_freq(struct a6xx_gmu *gmu, int index) struct msm_gpu *gpu = &adreno_gpu->base; int ret; + /* This can be called via devfreq even when the power is off */ + if (!pm_runtime_active(gmu->dev)) + return; + gmu_write(gmu, REG_A6XX_GMU_DCVS_ACK_OPTION, 0); gmu_write(gmu, REG_A6XX_GMU_DCVS_PERF_SETTING, diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c index 68af24150de5..443efc952f13 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c @@ -810,6 +810,10 @@ static unsigned long a6xx_gpu_busy(struct msm_gpu *gpu) struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu); u64 busy_cycles, busy_time; + /* devfreq can get here while we are idle so do a quick check first */ + if (!pm_runtime_active(a6xx_gpu->gmu.dev)) + return ~0LU; + busy_cycles = gmu_read64(&a6xx_gpu->gmu, REG_A6XX_GMU_CX_GMU_POWER_COUNTER_XOCLK_0_L, REG_A6XX_GMU_CX_GMU_POWER_COUNTER_XOCLK_0_H);