From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753413Ab3JVOBY (ORCPT ); Tue, 22 Oct 2013 10:01:24 -0400 Received: from gloria.sntech.de ([95.129.55.99]:36091 "EHLO gloria.sntech.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753220Ab3JVOBW (ORCPT ); Tue, 22 Oct 2013 10:01:22 -0400 From: Heiko =?utf-8?q?St=C3=BCbner?= To: Arnd Bergmann Subject: [PATCH v5 1/5] misc: sram: add ability to limit used sram areas Date: Tue, 22 Oct 2013 16:01:02 +0200 User-Agent: KMail/1.13.7 (Linux/3.2.0-2-amd64; KDE/4.8.4; x86_64; ; ) Cc: Olof Johansson , "linux-arm-kernel@lists.infradead.org" , Grant Likely , Rob Herring , devicetree-discuss@lists.ozlabs.org, Russell King , Philipp Zabel , linux-kernel@vger.kernel.org, "Greg Kroah-Hartman" , Ulrich Prinz , Matt Sealey , Fabio Estevam References: <201310221600.13562.heiko@sntech.de> In-Reply-To: <201310221600.13562.heiko@sntech.de> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201310221601.02661.heiko@sntech.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Some SoCs need parts of their sram for special purposes. So while being part of the peripheral, it should not be part of the genpool controlling the sram. Therefore add an option available to keep arbitrary portions of the sram from being part of the pool. If available is not present, all sram is used. Suggested-by: Rob Herring move from marking reserved space to available space Suggested-by: Matt Sealey Signed-off-by: Heiko Stuebner Tested-by: Ulrich Prinz --- Documentation/devicetree/bindings/misc/sram.txt | 8 ++++ drivers/misc/sram.c | 51 ++++++++++++++++++++--- 2 files changed, 53 insertions(+), 6 deletions(-) diff --git a/Documentation/devicetree/bindings/misc/sram.txt b/Documentation/devicetree/bindings/misc/sram.txt index 4d0a00e..8be552f 100644 --- a/Documentation/devicetree/bindings/misc/sram.txt +++ b/Documentation/devicetree/bindings/misc/sram.txt @@ -8,9 +8,17 @@ Required properties: - reg : SRAM iomem address range +Optional properties: + +- available: optional list of available chunks inside the sram that the + OS can use. Without available, the whole range is usable for the OS. + Format is , , ...; with base being relative to the + reg property base. + Example: sram: sram@5c000000 { compatible = "mmio-sram"; reg = <0x5c000000 0x40000>; /* 256 KiB SRAM at address 0x5c000000 */ + available = <0x100 0x3ff00>; }; diff --git a/drivers/misc/sram.c b/drivers/misc/sram.c index afe66571..755e640 100644 --- a/drivers/misc/sram.c +++ b/drivers/misc/sram.c @@ -42,6 +42,8 @@ static int sram_probe(struct platform_device *pdev) struct sram_dev *sram; struct resource *res; unsigned long size; + const __be32 *avail_list = NULL; + int avail_size = 0; int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -65,12 +67,49 @@ static int sram_probe(struct platform_device *pdev) if (!sram->pool) return -ENOMEM; - ret = gen_pool_add_virt(sram->pool, (unsigned long)virt_base, - res->start, size, -1); - if (ret < 0) { - if (sram->clk) - clk_disable_unprepare(sram->clk); - return ret; + if (pdev->dev.of_node) { + avail_list = of_get_property(pdev->dev.of_node, + "available", + &avail_size); + if (avail_list) { + avail_size /= sizeof(*avail_list); + if (!avail_size || avail_size % 2) { + dev_warn(&pdev->dev, "wrong number of arguments in available property\n"); + avail_list = NULL; + } + } + } + + if (!avail_list) { + ret = gen_pool_add_virt(sram->pool, (unsigned long)virt_base, + res->start, size, -1); + if (ret < 0) { + if (sram->clk) + clk_disable_unprepare(sram->clk); + return ret; + } + } else { + unsigned int astart; + unsigned int asize; + int i; + + for (i = 0; i < avail_size; i += 2) { + /* get the next available block */ + astart = be32_to_cpu(*avail_list++); + asize = be32_to_cpu(*avail_list++); + + dev_dbg(&pdev->dev, "found available block 0x%x-0x%x\n", + astart, astart + asize); + + ret = gen_pool_add_virt(sram->pool, + (unsigned long)virt_base + astart, + res->start + astart, asize, -1); + if (ret < 0) { + if (sram->clk) + clk_disable_unprepare(sram->clk); + return ret; + } + } } platform_set_drvdata(pdev, sram); -- 1.7.10.4