From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3670813CD62; Sun, 24 Mar 2024 22:41:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711320096; cv=none; b=HuC6n91nmgqOk/U4wgyd9zOqMAOkNU5P6z21BYyLApdayM64UMYHx7bmem4K4qKTIqiaAXLhVvqiI5ViWz26y0TXdLjNyXrwB+crJBkzNaxOsbDiiYokSJBUNQyezz1zmegJuzp1IX0Klw4JnfjVXdjTto/G0BnQfksDg4K2j3c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711320096; c=relaxed/simple; bh=pCc5yRqiW7zrM8WJbTTAP0OTtZg+beqdp63g2hcZTaQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=mLypyTdQxO9fUoeqegz230WeqbxYqDfDMGhQCB2+VF+SiFId9HsnN8CeJDOmBVcgl9EmWxiJxnRQTCpBFC2bqKomphG8UzF1SUb+sq5Bvuhj0l+HRluZXBEImu5bi+PozMLb4AMUbSJ6lZuO+uRmy9rZBTO4xb/ydVzWRSio1qM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fFpr9L4z; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fFpr9L4z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0A651C433A6; Sun, 24 Mar 2024 22:41:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711320095; bh=pCc5yRqiW7zrM8WJbTTAP0OTtZg+beqdp63g2hcZTaQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fFpr9L4zdcGREvzwDtMfzHUrpnDhIbFWq31PrdKeJApzNp1A4WpZcnHi0oHPPwPzh QCFnq4tGdKLUtGztkp5ikNz/cehOhDFOZbLaaSvIUPyn/uybX2CVJaw7yMUc6A/m+a FYWUTo/zXZqClNlUQBVz94+EzEM0bAnJAvPW30gZubBRmg++G8JEb2dBQV+Joo4wv/ Re3zovD7tyN0YTYxAcDKTK+BF9QohX622Z02nxrnonGv0VL11iJreFWg9CFMNVE0iv WX/M8EMj2hBf+oGASoaVA59zY3eRSy59y82nnmBufDR6QkuDfVQQTZ0CxdFTbO1/Rn Vd66j6E/LTkxw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Konrad Dybcio , Bjorn Andersson , Sasha Levin Subject: [PATCH 6.8 404/715] clk: qcom: reset: Ensure write completion on reset de/assertion Date: Sun, 24 Mar 2024 18:29:43 -0400 Message-ID: <20240324223455.1342824-405-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324223455.1342824-1-sashal@kernel.org> References: <20240324223455.1342824-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Konrad Dybcio [ Upstream commit 2f8cf2c3f3e3f7ef61bd19abb4b0bb797ad50aaf ] Trying to toggle the resets in a rapid fashion can lead to the changes not actually arriving at the clock controller block when we expect them to. This was observed at least on SM8250. Read back the value after regmap_update_bits to ensure write completion. Fixes: b36ba30c8ac6 ("clk: qcom: Add reset controller support") Signed-off-by: Konrad Dybcio Link: https://lore.kernel.org/r/20240105-topic-venus_reset-v2-3-c37eba13b5ce@linaro.org Signed-off-by: Bjorn Andersson Signed-off-by: Sasha Levin --- drivers/clk/qcom/reset.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/clk/qcom/reset.c b/drivers/clk/qcom/reset.c index 20d1d35aaf229..d96c96a9089f4 100644 --- a/drivers/clk/qcom/reset.c +++ b/drivers/clk/qcom/reset.c @@ -33,7 +33,12 @@ static int qcom_reset_set_assert(struct reset_controller_dev *rcdev, map = &rst->reset_map[id]; mask = map->bitmask ? map->bitmask : BIT(map->bit); - return regmap_update_bits(rst->regmap, map->reg, mask, assert ? mask : 0); + regmap_update_bits(rst->regmap, map->reg, mask, assert ? mask : 0); + + /* Read back the register to ensure write completion, ignore the value */ + regmap_read(rst->regmap, map->reg, &mask); + + return 0; } static int qcom_reset_assert(struct reset_controller_dev *rcdev, unsigned long id) -- 2.43.0