From patchwork Tue Jan 28 23:36:11 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Peter De Schrijver X-Patchwork-Id: 3548701 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 591CC9F381 for ; Tue, 28 Jan 2014 23:37:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6719220172 for ; Tue, 28 Jan 2014 23:37:58 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 69B0B20109 for ; Tue, 28 Jan 2014 23:37:57 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W8IDf-0006e0-8k; Tue, 28 Jan 2014 23:37:27 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1W8IDV-0002dm-19; Tue, 28 Jan 2014 23:37:17 +0000 Received: from hqemgate16.nvidia.com ([216.228.121.65]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W8IDG-0002bd-CD for linux-arm-kernel@lists.infradead.org; Tue, 28 Jan 2014 23:37:04 +0000 Received: from hqnvupgp07.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com id ; Tue, 28 Jan 2014 15:37:20 -0800 Received: from hqemhub02.nvidia.com ([172.20.12.94]) by hqnvupgp07.nvidia.com (PGP Universal service); Tue, 28 Jan 2014 15:35:25 -0800 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Tue, 28 Jan 2014 15:35:25 -0800 Received: from hqnvemgw02.nvidia.com (172.16.227.111) by hqemhub02.nvidia.com (172.20.150.31) with Microsoft SMTP Server id 8.3.327.1; Tue, 28 Jan 2014 15:36:43 -0800 Received: from thelma.nvidia.com (Not Verified[172.16.212.77]) by hqnvemgw02.nvidia.com with MailMarshal (v7,1,2,5326) id ; Tue, 28 Jan 2014 15:36:44 -0800 Received: from tbergstrom-lnx.nvidia.com (tbergstrom-lnx.nvidia.com [10.21.24.170]) by thelma.nvidia.com (8.13.8+Sun/8.8.8) with ESMTP id s0SNaV0u003792; Tue, 28 Jan 2014 15:36:40 -0800 (PST) From: Peter De Schrijver To: Peter De Schrijver Subject: [PATCH v3 1/6] ARM: tegra: export apb dma readl/writel Date: Wed, 29 Jan 2014 01:36:11 +0200 Message-ID: <1390952176-30402-2-git-send-email-pdeschrijver@nvidia.com> X-Mailer: git-send-email 1.7.7.rc0.72.g4b5ea.dirty In-Reply-To: <1390952176-30402-1-git-send-email-pdeschrijver@nvidia.com> References: <1390952176-30402-1-git-send-email-pdeschrijver@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140128_183702_656133_059A59EF X-CRM114-Status: GOOD ( 15.08 ) X-Spam-Score: -2.4 (--) Cc: Russell King , Stephen Warren , Linus Walleij , Wolfram Sang , linux-kernel@vger.kernel.org, Thierry Reding , linux-tegra@vger.kernel.org, Andrew Morton , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.7 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Export APB DMA readl and writel. These are needed because we can't access the fuses directly on Tegra20 without potentially causing a system hang. Also have the APB DMA readl and writel return an error in case of a read failure instead of just returning zero or ignore write failures. Signed-off-by: Peter De Schrijver --- arch/arm/mach-tegra/apbio.c | 51 ++++++++++++++++++++++++++---------------- include/linux/tegra-soc.h | 14 +++++++++++ 2 files changed, 45 insertions(+), 20 deletions(-) diff --git a/arch/arm/mach-tegra/apbio.c b/arch/arm/mach-tegra/apbio.c index bc47197..e0bf49d 100644 --- a/arch/arm/mach-tegra/apbio.c +++ b/arch/arm/mach-tegra/apbio.c @@ -32,8 +32,8 @@ static u32 *tegra_apb_bb; static dma_addr_t tegra_apb_bb_phys; static DECLARE_COMPLETION(tegra_apb_wait); -static u32 tegra_apb_readl_direct(unsigned long offset); -static void tegra_apb_writel_direct(u32 value, unsigned long offset); +static int tegra_apb_readl_direct(unsigned long offset, u32 *value); +static int tegra_apb_writel_direct(u32 value, unsigned long offset); static struct dma_chan *tegra_apb_dma_chan; static struct dma_slave_config dma_sconfig; @@ -128,58 +128,64 @@ static int do_dma_transfer(unsigned long apb_add, return 0; } -static u32 tegra_apb_readl_using_dma(unsigned long offset) +int tegra_apb_readl_using_dma(unsigned long offset, u32 *value) { int ret; if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) - return tegra_apb_readl_direct(offset); + return tegra_apb_readl_direct(offset, value); mutex_lock(&tegra_apb_dma_lock); ret = do_dma_transfer(offset, DMA_DEV_TO_MEM); - if (ret < 0) { + if (ret < 0) pr_err("error in reading offset 0x%08lx using dma\n", offset); - *(u32 *)tegra_apb_bb = 0; - } + else + *value = *tegra_apb_bb; + mutex_unlock(&tegra_apb_dma_lock); - return *((u32 *)tegra_apb_bb); + + return ret; } -static void tegra_apb_writel_using_dma(u32 value, unsigned long offset) +int tegra_apb_writel_using_dma(u32 value, unsigned long offset) { int ret; - if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) { - tegra_apb_writel_direct(value, offset); - return; - } + if (!tegra_apb_dma_chan && !tegra_apb_dma_init()) + return tegra_apb_writel_direct(value, offset); mutex_lock(&tegra_apb_dma_lock); *((u32 *)tegra_apb_bb) = value; ret = do_dma_transfer(offset, DMA_MEM_TO_DEV); + mutex_unlock(&tegra_apb_dma_lock); if (ret < 0) pr_err("error in writing offset 0x%08lx using dma\n", offset); - mutex_unlock(&tegra_apb_dma_lock); + + return ret; } #else #define tegra_apb_readl_using_dma tegra_apb_readl_direct #define tegra_apb_writel_using_dma tegra_apb_writel_direct #endif -typedef u32 (*apbio_read_fptr)(unsigned long offset); -typedef void (*apbio_write_fptr)(u32 value, unsigned long offset); +typedef int (*apbio_read_fptr)(unsigned long offset, u32 *value); +typedef int (*apbio_write_fptr)(u32 value, unsigned long offset); static apbio_read_fptr apbio_read; static apbio_write_fptr apbio_write; -static u32 tegra_apb_readl_direct(unsigned long offset) +static int tegra_apb_readl_direct(unsigned long offset, u32 *value) { - return readl(IO_ADDRESS(offset)); + *value = readl(IO_ADDRESS(offset)); + + return 0; } -static void tegra_apb_writel_direct(u32 value, unsigned long offset) +static int tegra_apb_writel_direct(u32 value, unsigned long offset) { writel(value, IO_ADDRESS(offset)); + + return 0; } void tegra_apb_io_init(void) @@ -197,7 +203,12 @@ void tegra_apb_io_init(void) u32 tegra_apb_readl(unsigned long offset) { - return apbio_read(offset); + u32 val; + + if (apbio_read(offset, &val) < 0) + return 0; + else + return val; } void tegra_apb_writel(u32 value, unsigned long offset) diff --git a/include/linux/tegra-soc.h b/include/linux/tegra-soc.h index 95f611d..b02d73b 100644 --- a/include/linux/tegra-soc.h +++ b/include/linux/tegra-soc.h @@ -19,4 +19,18 @@ u32 tegra_read_chipid(void); + +#if defined(CONFIG_TEGRA20_APB_DMA) +int tegra_apb_readl_using_dma(unsigned long offset, u32 *value); +int tegra_apb_writel_using_dma(u32 value, unsigned long offset); +#else +static inline int tegra_apb_readl_using_dma(unsigned long offset, u32 *value) +{ + return -EINVAL; +} +static inline int tegra_apb_writel_using_dma(u32 value, unsigned long offset) +{ + return -EINVAL; +} +#endif #endif /* __LINUX_TEGRA_SOC_H_ */