| Message ID | 1420772036-3112-3-git-send-email-tthayer@opensource.altera.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Jan 09, 2015 at 02:53:53AM +0000, tthayer@opensource.altera.com wrote: > From: Thor Thayer <tthayer@opensource.altera.com> > > 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. Where else is this OCRAM used? If we need the ECC to be enabled before use, a module_init call that seems to be unrelated to any other usage doesn't seem right to me. Hopefully I've just misunderstood something here. > > Signed-off-by: Thor Thayer <tthayer@opensource.altera.com> > --- > 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)); Why divide by sizeof(size_t) here? As far as I am aware, resource_size gives you a size in bytes... > + 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); ...and here we write size bytes, not (size / sizeof(size_t)) bytes, so we're poking memory we weren't allocated. How is this memory mapped exactly? Is memset safe? Thanks, Mark. > + > + 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 > >
Hi Mark, On 02/06/2015 12:45 PM, Mark Rutland wrote: > On Fri, Jan 09, 2015 at 02:53:53AM +0000, tthayer@opensource.altera.com wrote: >> From: Thor Thayer <tthayer@opensource.altera.com> >> >> 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. > > Where else is this OCRAM used? > > If we need the ECC to be enabled before use, a module_init call that > seems to be unrelated to any other usage doesn't seem right to me. > Hopefully I've just misunderstood something here. > Thank you for reviewing this. The OCRAM will be used to store data and functions for putting and removing the SoC from sleep. However, in this scenario, we won't have the ECC enabled. To initialize ECC, the OCRAM needs to enable ECC then clear the entire memory to zero before using it. Doing this early in the startup sequence seemed appropriate. Maybe I'm misunderstanding your concern. < snip> >> +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)); > > Why divide by sizeof(size_t) here? As far as I am aware, resource_size > gives you a size in bytes... > Yes, you are right. I shouldn't have changed this - for some reason when I re-read the function prototype, I thought this function was allocating integers. Thank you. >> + 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); > > ...and here we write size bytes, not (size / sizeof(size_t)) bytes, so > we're poking memory we weren't allocated. > > How is this memory mapped exactly? Is memset safe? > > Thanks, > Mark. > Yes, thank you for catching that. OK. I think I understand your point now. I need to enable the OCRAM ECC before the gen_pool_create() which is called by the "ocram:sram@ffff0000" node. In that case, I should move this OCRAM ECC enable into the same place as L2 ecc is enabled. Thor >> + >> + 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 >> >>
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);