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[94.29.35.107]) by smtp.gmail.com with ESMTPSA id l26sm281030pfb.20.2019.04.17.15.34.10 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 17 Apr 2019 15:34:16 -0700 (PDT) From: Dmitry Osipenko To: Thierry Reding , Jonathan Hunter , MyungJoo Ham , Kyungmin Park , Chanwoo Choi , Tomeu Vizoso Cc: linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: [PATCH v3 03/16] PM / devfreq: tegra: Replace write memory barrier with the read barrier Date: Thu, 18 Apr 2019 01:29:12 +0300 Message-Id: <20190417222925.5815-4-digetx@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190417222925.5815-1-digetx@gmail.com> References: <20190417222925.5815-1-digetx@gmail.com> MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The write memory barrier isn't needed because the BUS buffer is flushed by read after write that happens after the removed wmb(), we will also use readl() instead of the relaxed version to ensure that read is indeed completed. Reviewed-by: Chanwoo Choi Signed-off-by: Dmitry Osipenko --- drivers/devfreq/tegra-devfreq.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c index f7378a42d184..7d7b9a5895b2 100644 --- a/drivers/devfreq/tegra-devfreq.c +++ b/drivers/devfreq/tegra-devfreq.c @@ -243,8 +243,7 @@ static void tegra_devfreq_update_wmark(struct tegra_devfreq *tegra, static void actmon_write_barrier(struct tegra_devfreq *tegra) { /* ensure the update has reached the ACTMON */ - wmb(); - actmon_readl(tegra, ACTMON_GLB_STATUS); + readl(tegra->regs + ACTMON_GLB_STATUS); } static void actmon_isr_device(struct tegra_devfreq *tegra,