From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751862AbeETNtr (ORCPT ); Sun, 20 May 2018 09:49:47 -0400 Received: from mail-wr0-f196.google.com ([209.85.128.196]:45589 "EHLO mail-wr0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751162AbeETNtP (ORCPT ); Sun, 20 May 2018 09:49:15 -0400 X-Google-Smtp-Source: AB8JxZqhyvieD2B6tvIXfvTvaN36iNLlcY8ZoC9ewaFFlc8V6h5/exGh5he5Z207N+0YCYoPG2b07Q== From: Dmitry Osipenko To: Hans Verkuil , Mauro Carvalho Chehab , Thierry Reding , Jonathan Hunter Cc: linux-tegra@vger.kernel.org, linux-media@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: [PATCH v1] media: staging: tegra-vde: Reset memory client Date: Sun, 20 May 2018 16:48:45 +0300 Message-Id: <20180520134846.31046-2-digetx@gmail.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180520134846.31046-1-digetx@gmail.com> References: <20180520134846.31046-1-digetx@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org DMA requests must be blocked before resetting VDE HW, otherwise it is possible to get a memory corruption or a machine hang. Use the reset control provided by the Memory Controller to block DMA before resetting the VDE HW. Signed-off-by: Dmitry Osipenko --- drivers/staging/media/tegra-vde/tegra-vde.c | 42 +++++++++++++++++++-- 1 file changed, 38 insertions(+), 4 deletions(-) diff --git a/drivers/staging/media/tegra-vde/tegra-vde.c b/drivers/staging/media/tegra-vde/tegra-vde.c index 90177a59b97c..6dd3bf4481be 100644 --- a/drivers/staging/media/tegra-vde/tegra-vde.c +++ b/drivers/staging/media/tegra-vde/tegra-vde.c @@ -73,6 +73,7 @@ struct tegra_vde { struct mutex lock; struct miscdevice miscdev; struct reset_control *rst; + struct reset_control *rst_mc; struct gen_pool *iram_pool; struct completion decode_completion; struct clk *clk; @@ -850,9 +851,23 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde, * We rely on the VDE registers reset value, otherwise VDE * causes bus lockup. */ + ret = reset_control_assert(vde->rst_mc); + if (ret) { + dev_err(dev, "DEC start: Failed to assert MC reset: %d\n", + ret); + goto put_runtime_pm; + } + ret = reset_control_reset(vde->rst); if (ret) { - dev_err(dev, "Failed to reset HW: %d\n", ret); + dev_err(dev, "DEC start: Failed to reset HW: %d\n", ret); + goto put_runtime_pm; + } + + ret = reset_control_deassert(vde->rst_mc); + if (ret) { + dev_err(dev, "DEC start: Failed to deassert MC reset: %d\n", + ret); goto put_runtime_pm; } @@ -880,9 +895,21 @@ static int tegra_vde_ioctl_decode_h264(struct tegra_vde *vde, ret = timeout; } - err = reset_control_assert(vde->rst); - if (err) - dev_err(dev, "Failed to assert HW reset: %d\n", err); + /* + * At first reset memory client to avoid resetting VDE HW in the + * middle of DMA which could result into memory corruption or hang + * the whole system. + */ + err = reset_control_assert(vde->rst_mc); + if (!err) { + err = reset_control_assert(vde->rst); + if (err) + dev_err(dev, + "DEC end: Failed to assert HW reset: %d\n", + err); + } else { + dev_err(dev, "DEC end: Failed to assert MC reset: %d\n", err); + } put_runtime_pm: pm_runtime_mark_last_busy(dev); @@ -1074,6 +1101,13 @@ static int tegra_vde_probe(struct platform_device *pdev) return err; } + vde->rst_mc = devm_reset_control_get_optional(dev, "mc"); + if (IS_ERR(vde->rst_mc)) { + err = PTR_ERR(vde->rst_mc); + dev_err(dev, "Could not get MC reset %d\n", err); + return err; + } + irq = platform_get_irq_byname(pdev, "sync-token"); if (irq < 0) return irq; -- 2.17.0