Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932465AbaLBPMF (ORCPT ); Tue, 2 Dec 2014 10:12:05 -0500 Received: from cam-admin0.cambridge.arm.com ([217.140.96.50]:41864 "EHLO cam-admin0.cambridge.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932413AbaLBPMB (ORCPT ); Tue, 2 Dec 2014 10:12:01 -0500 Date: Tue, 2 Dec 2014 15:11:45 +0000 From: Mark Rutland To: "tthayer@opensource.altera.com" Cc: "bp@alien8.de" , "dougthompson@xmission.com" , "m.chehab@samsung.com" , "robh+dt@kernel.org" , Pawel Moll , "ijc+devicetree@hellion.org.uk" , "galak@codeaurora.org" , "linux@arm.linux.org.uk" , "dinguyen@opensource.altera.com" , "grant.likely@linaro.org" , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" , "linux-edac@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "tthayer.linux@gmail.com" Subject: Re: [PATCHv5 2/5] arm: socfpga: Enable OCRAM ECC on startup. Message-ID: <20141202151145.GN23671@leverpostej> References: <1415751263-1830-1-git-send-email-tthayer@opensource.altera.com> <1415751263-1830-3-git-send-email-tthayer@opensource.altera.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1415751263-1830-3-git-send-email-tthayer@opensource.altera.com> Thread-Topic: [PATCHv5 2/5] arm: socfpga: Enable OCRAM ECC on startup. Accept-Language: en-GB, en-US Content-Language: en-US User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 12, 2014 at 12:14:20AM +0000, tthayer@opensource.altera.com wrote: > From: Thor Thayer > > This patch enables the ECC for On-Chip RAM on machine > startup. The ECC has to be enabled before data is > is stored in memory otherwise the ECC will fail on > reads. > > Signed-off-by: Thor Thayer > --- > v2: Split OCRAM ECC portion separately. Addition of iounmap() > and reorganization of gen_pool_free. Remove defconfig from patch. > > v3/4: No change > > v5: Remove ocram.h, use io.h instead of clk-provider.h > Check prop in correct place. Add ECC EN defines. > --- > arch/arm/mach-socfpga/Makefile | 1 + > arch/arm/mach-socfpga/core.h | 1 + > arch/arm/mach-socfpga/ocram.c | 90 +++++++++++++++++++++++++++++++++++++++ > arch/arm/mach-socfpga/socfpga.c | 9 ++++ > 4 files changed, 101 insertions(+) > create mode 100644 arch/arm/mach-socfpga/ocram.c > > diff --git a/arch/arm/mach-socfpga/Makefile b/arch/arm/mach-socfpga/Makefile > index 142609e..1552ca5 100644 > --- a/arch/arm/mach-socfpga/Makefile > +++ b/arch/arm/mach-socfpga/Makefile > @@ -5,3 +5,4 @@ > obj-y := socfpga.o > obj-$(CONFIG_SMP) += headsmp.o platsmp.o > obj-$(CONFIG_EDAC_ALTERA_L2C) += l2_cache.o > +obj-$(CONFIG_EDAC_ALTERA_OCRAM) += ocram.o > diff --git a/arch/arm/mach-socfpga/core.h b/arch/arm/mach-socfpga/core.h > index 385baba..f3eee32 100644 > --- a/arch/arm/mach-socfpga/core.h > +++ b/arch/arm/mach-socfpga/core.h > @@ -45,5 +45,6 @@ extern unsigned long cpu1start_addr; > #define SOCFPGA_SCU_VIRT_BASE 0xfffec000 > > void socfpga_init_l2_ecc(void); > +void socfpga_init_ocram_ecc(void); > > #endif > diff --git a/arch/arm/mach-socfpga/ocram.c b/arch/arm/mach-socfpga/ocram.c > new file mode 100644 > index 0000000..a83b34f > --- /dev/null > +++ b/arch/arm/mach-socfpga/ocram.c > @@ -0,0 +1,90 @@ > +/* > + * Copyright Altera Corporation (C) 2014. All rights reserved. > + * > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + * > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + * > + * You should have received a copy of the GNU General Public License along with > + * this program. If not, see . > + */ > +#include > +#include > +#include > + > +#define ALTR_OCRAM_CLEAR_ECC 0x00000018 > +#define ALTR_OCRAM_ECC_EN 0x00000019 > + > +void socfpga_init_ocram_ecc(void) > +{ > + struct device_node *np; > + const __be32 *prop; Please don't use accessors which return raw __be32s in drivers, typically it's the wrong thing to do and leaves horrible bugs and/or quirks that are painful to fix up. > + u32 ocr_edac_addr, iram_addr, len; > + void __iomem *mapped_ocr_edac_addr; > + size_t size; > + struct gen_pool *gp; > + > + np = of_find_compatible_node(NULL, NULL, "altr,ocram-edac"); > + if (!np) { > + pr_err("SOCFPGA: Unable to find altr,ocram-edac in dtb\n"); > + return; > + } > + > + prop = of_get_property(np, "reg", &size); > + if (!prop || size < sizeof(*prop)) { > + pr_err("SOCFPGA: Unable to find OCRAM ECC mapping in dtb\n"); > + return; > + } > + ocr_edac_addr = be32_to_cpup(prop++); > + len = be32_to_cpup(prop); Use of_iomap(np, 0). You don't seem to pass the address around, so that should be sufficient. > + > + gp = of_get_named_gen_pool(np, "iram", 0); > + if (!gp) { > + pr_err("SOCFPGA: OCRAM cannot find gen pool\n"); > + return; > + } > + > + np = of_find_compatible_node(NULL, NULL, "mmio-sram"); > + if (!np) { > + pr_err("SOCFPGA: Unable to find mmio-sram in dtb\n"); > + return; > + } > + > + /* Determine the OCRAM address and size */ > + prop = of_get_property(np, "reg", &size); > + if (!prop || size < sizeof(*prop)) { > + pr_err("SOCFPGA: Unable to find OCRAM mapping in dtb\n"); > + return; > + } > + iram_addr = be32_to_cpup(prop++); > + len = be32_to_cpup(prop); This address is overwritten below. What's going on? > + > + iram_addr = gen_pool_alloc(gp, len); > + if (iram_addr == 0) { > + pr_err("SOCFPGA: cannot alloc from gen pool\n"); > + return; > + } > + > + memset((void *)iram_addr, 0, len); How is the iram mapped? Is memset to it safe (e.g. it unaligned accesses are made)? > + > + gen_pool_free(gp, iram_addr, len); > + > + mapped_ocr_edac_addr = ioremap(ocr_edac_addr, 4); > + if (!mapped_ocr_edac_addr) { > + pr_err("SOCFPGA: Unable to map OCRAM ecc regs.\n"); > + return; > + } > + > + /* Clear any pending OCRAM ECC interrupts, then enable ECC */ > + writel(ALTR_OCRAM_CLEAR_ECC, mapped_ocr_edac_addr); > + writel(ALTR_OCRAM_ECC_EN, mapped_ocr_edac_addr); > + > + iounmap(mapped_ocr_edac_addr); > + > + pr_debug("SOCFPGA: Success Initializing OCRAM\n"); > +} > diff --git a/arch/arm/mach-socfpga/socfpga.c b/arch/arm/mach-socfpga/socfpga.c > index 0954011..065d80d 100644 > --- a/arch/arm/mach-socfpga/socfpga.c > +++ b/arch/arm/mach-socfpga/socfpga.c > @@ -100,6 +100,14 @@ static void socfpga_cyclone5_restart(enum reboot_mode mode, const char *cmd) > writel(temp, rst_manager_base_addr + SOCFPGA_RSTMGR_CTRL); > } > > +static void __init socfpga_cyclone5_init(void) > +{ > + of_platform_populate(NULL, of_default_bus_match_table, > + NULL, NULL); > + if (IS_ENABLED(CONFIG_EDAC_ALTERA_OCRAM)) > + socfpga_init_ocram_ecc(); If it's safe to do this after probing everything else, why can't this be a normal device probe? Thanks, Mark. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/