From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755226AbcCNIjb (ORCPT ); Mon, 14 Mar 2016 04:39:31 -0400 Received: from down.free-electrons.com ([37.187.137.238]:47336 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751342AbcCNIjM (ORCPT ); Mon, 14 Mar 2016 04:39:12 -0400 From: Gregory CLEMENT To: "David S. Miller" , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, Thomas Petazzoni , Florian Fainelli Cc: Jason Cooper , Andrew Lunn , Sebastian Hesselbarth , Gregory CLEMENT , linux-arm-kernel@lists.infradead.org, Lior Amsalem , Nadav Haklai , Marcin Wojtas , Simon Guinot , Russell King - ARM Linux , Willy Tarreau , Timor Kardashov , Dmitri Epshtein , Sebastian Careba Subject: [PATCH v6 net-next 01/10] misc: sram: add optional ioremap without write combining Date: Mon, 14 Mar 2016 09:38:56 +0100 Message-Id: <1457944745-7634-2-git-send-email-gregory.clement@free-electrons.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1457944745-7634-1-git-send-email-gregory.clement@free-electrons.com> References: <1457944745-7634-1-git-send-email-gregory.clement@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marcin Wojtas Some SRAM users may require non-bufferable access to the memory, which is impossible, because devm_ioremap_wc() is used for setting sram->virt_base. This commit adds optional flag 'no-memory-wc', which allow to choose remap method, using DT property. Documentation is updated accordingly. Signed-off-by: Marcin Wojtas --- Documentation/devicetree/bindings/sram/sram.txt | 5 +++++ drivers/misc/sram.c | 5 ++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/sram/sram.txt b/Documentation/devicetree/bindings/sram/sram.txt index 42ee9438b771..227e3a341af1 100644 --- a/Documentation/devicetree/bindings/sram/sram.txt +++ b/Documentation/devicetree/bindings/sram/sram.txt @@ -25,6 +25,11 @@ Required properties in the sram node: - ranges : standard definition, should translate from local addresses within the sram to bus addresses +Optional properties in the sram node: + +- no-memory-wc : the flag indicating, that SRAM memory region has not to + be remapped as write combining. WC is used by default. + Required properties in the area nodes: - reg : iomem address range, relative to the SRAM range diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c index 736dae715dbf..69cdabea9c03 100644 --- a/drivers/misc/sram.c +++ b/drivers/misc/sram.c @@ -360,7 +360,10 @@ static int sram_probe(struct platform_device *pdev) return -EBUSY; } - sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size); + if (of_property_read_bool(pdev->dev.of_node, "no-memory-wc")) + sram->virt_base = devm_ioremap(sram->dev, res->start, size); + else + sram->virt_base = devm_ioremap_wc(sram->dev, res->start, size); if (IS_ERR(sram->virt_base)) return PTR_ERR(sram->virt_base); -- 2.5.0