From: Thor Thayer <tthayer@xxxxxxxxxxxxxxxxxxxxx> 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 <tthayer@xxxxxxxxxxxxxxxxxxxxx> --- 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. v6: Implement OCRAM discovery changes from community. Add of_node_put(). Remove be32_to_cpup(). Use __init() which allows removal of .init_machine(). Update year in header. --- arch/arm/mach-socfpga/Makefile | 1 + arch/arm/mach-socfpga/ocram.c | 97 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 98 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/ocram.c b/arch/arm/mach-socfpga/ocram.c new file mode 100644 index 0000000..1f12a38 --- /dev/null +++ b/arch/arm/mach-socfpga/ocram.c @@ -0,0 +1,97 @@ +/* + * Copyright Altera Corporation (C) 2015. 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 <http://www.gnu.org/licenses/>. + */ +#include <linux/io.h> +#include <linux/genalloc.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_platform.h> + +#define ALTR_OCRAM_CLEAR_ECC 0x00000018 +#define ALTR_OCRAM_ECC_EN 0x00000019 + +static int __init socfpga_init_ocram_ecc(void) +{ + struct device_node *np; + struct resource res; + u32 iram_addr; + void __iomem *mapped_ocr_edac_addr; + resource_size_t size; + struct gen_pool *gp; + int ret; + + /* Get the size of the on-chip RAM */ + np = of_find_compatible_node(NULL, NULL, "mmio-sram"); + if (!np) { + pr_err("%s: Unable to find mmio-sram in dtb\n", __func__); + return -ENODEV; + } + + ret = of_address_to_resource(np, 0, &res); + if (ret) { + of_node_put(np); + pr_err("%s: Problem getting SRAM address in dtb\n", __func__); + return -ENODEV; + } + size = resource_size(&res); + of_node_put(np); + + /* Find the OCRAM EDAC device tree node */ + np = of_find_compatible_node(NULL, NULL, "altr,ocram-edac"); + if (!np) { + pr_err("%s: Unable to find altr,ocram-edac\n", __func__); + return -ENODEV; + } + + mapped_ocr_edac_addr = of_iomap(np, 0); + if (!mapped_ocr_edac_addr) { + of_node_put(np); + pr_err("%s: Unable to map OCRAM ecc regs.\n", __func__); + return -ENODEV; + } + + gp = of_get_named_gen_pool(np, "iram", 0); + if (!gp) { + of_node_put(np); + pr_err("%s: OCRAM cannot find gen pool\n", __func__); + return -ENODEV; + } + of_node_put(np); + + iram_addr = gen_pool_alloc(gp, size / sizeof(size_t)); + if (iram_addr == 0) { + pr_err("%s: cannot alloc from gen pool\n", __func__); + return -ENODEV; + } + + /* 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); + + memset((void *)iram_addr, 0, size); + + gen_pool_free(gp, iram_addr, size / sizeof(size_t)); + + iounmap(mapped_ocr_edac_addr); + + return 0; +} + +static void __exit socfpga_exit_ocram_ecc(void) +{ +} + +module_init(socfpga_init_ocram_ecc); +module_exit(socfpga_exit_ocram_ecc); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html