[PATCH 1/2] EDAC: Add Aspeed AST2500 EDAC driver

From: Stefan Schaeckeler
Date: Mon Dec 17 2018 - 01:04:10 EST

From: Stefan M Schaeckeler <sschaeck@xxxxxxxxx>

Add support for the Aspeed AST2500 SoC EDAC driver.

Signed-off-by: Stefan M Schaeckeler <sschaeck@xxxxxxxxx>
---
MAINTAINERS | 6 +
arch/arm/boot/dts/aspeed-g5.dtsi | 7 +
drivers/edac/Kconfig | 7 +
drivers/edac/Makefile | 1 +
drivers/edac/aspeed_edac.c | 457 +++++++++++++++++++++++++++++++
5 files changed, 478 insertions(+)
create mode 100644 drivers/edac/aspeed_edac.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 3318f30903b2..1feb92b14029 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5315,6 +5315,12 @@ L: linux-edac@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/edac/amd64_edac*

+EDAC-AST2500
+M: Stefan Schaeckeler <sschaeck@xxxxxxxxx>
+S: Supported
+F: drivers/edac/aspeed_edac.c
+F: Documentation/devicetree/bindings/edac/aspeed-sdram-edac.txt
+
EDAC-CALXEDA
M: Robert Richter <rric@xxxxxxxxxx>
L: linux-edac@xxxxxxxxxxxxxxx
diff --git a/arch/arm/boot/dts/aspeed-g5.dtsi b/arch/arm/boot/dts/aspeed-g5.dtsi
index d107459fc0f8..b4e479ab5a2d 100644
--- a/arch/arm/boot/dts/aspeed-g5.dtsi
+++ b/arch/arm/boot/dts/aspeed-g5.dtsi
@@ -47,6 +47,13 @@
reg = <0x80000000 0>;
};

+ edac: sdram@1e6e0000 {
+ compatible = "aspeed,ast2500-sdram-edac";
+ reg = <0x1e6e0000 0x174>;
+ interrupts = <0>;
+ status = "disabled";
+ };
+
ahb {
compatible = "simple-bus";
#address-cells = <1>;
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 41c9ccdd20d6..67834430b0a1 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -475,4 +475,11 @@ config EDAC_QCOM
For debugging issues having to do with stability and overall system
health, you should probably say 'Y' here.

+config EDAC_ASPEED
+ tristate "Aspeed AST 2500 SoC"
+ depends on MACH_ASPEED_G5
+ help
+ Support for error detection and correction on the
+ Aspeed AST 2500 SoC.
+
endif # EDAC
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 716096d08ea0..e1f23d4ff860 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -78,3 +78,4 @@ obj-$(CONFIG_EDAC_SYNOPSYS) += synopsys_edac.o
obj-$(CONFIG_EDAC_XGENE) += xgene_edac.o
obj-$(CONFIG_EDAC_TI) += ti_edac.o
obj-$(CONFIG_EDAC_QCOM) += qcom_edac.o
+obj-$(CONFIG_EDAC_ASPEED) += aspeed_edac.o
diff --git a/drivers/edac/aspeed_edac.c b/drivers/edac/aspeed_edac.c
new file mode 100644
index 000000000000..d6ed119909eb
--- /dev/null
+++ b/drivers/edac/aspeed_edac.c
@@ -0,0 +1,457 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018 Cisco Systems
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/edac.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/stop_machine.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/regmap.h>
+#include <asm/page.h>
+#include "edac_module.h"
+
+
+#define DRV_NAME "aspeed-edac"
+
+
+/* registers */
+#define ASPEED_MCR_PROT 0x00 /* protection key register */
+#define ASPEED_MCR_CONF 0x04 /* configuration register */
+#define ASPEED_MCR_INTR_CTRL 0x50 /* interrupt control/status register */
+#define ASPEED_MCR_ADDR_UNREC 0x58 /* address of first un-recoverable error */
+#define ASPEED_MCR_ADDR_REC 0x5c /* address of last recoverable error */
+#define ASPEED_MCR_LAST ASPEED_MCR_ADDR_REC
+
+
+/* bits and masks */
+#define ASPEED_MCR_PROT_PASSWD 0xfc600309
+#define ASPEED_MCR_CONF_DRAM_TYPE BIT(4)
+#define ASPEED_MCR_CONF_ECC BIT(7)
+#define ASPEED_MCR_INTR_CTRL_CLEAR BIT(31)
+#define ASPEED_MCR_INTR_CTRL_CNT_REC GENMASK(23, 16)
+#define ASPEED_MCR_INTR_CTRL_CNT_UNREC GENMASK(15, 12)
+#define ASPEED_MCR_INTR_CTRL_ENABLE (BIT(0) | BIT(1))
+
+
+
+static int aspeed_edac_regmap_reg_write(void *context, unsigned int reg,
+ unsigned int val)
+{
+ void __iomem *regs = (void __iomem *)context;
+
+ /* enable write to MCR register set */
+ writel(ASPEED_MCR_PROT_PASSWD, regs + ASPEED_MCR_PROT);
+
+ writel(val, regs + reg);
+
+ /* disable write to MCR register set */
+ writel(~ASPEED_MCR_PROT_PASSWD, regs + ASPEED_MCR_PROT);
+
+ return 0;
+}
+
+
+static int aspeed_edac_regmap_reg_read(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ void __iomem *regs = (void __iomem *)context;
+
+ *val = readl(regs + reg);
+
+ return 0;
+}
+
+static bool aspeed_edac_regmap_is_volatile(struct device *dev,
+ unsigned int reg)
+{
+ switch (reg) {
+ case ASPEED_MCR_PROT:
+ case ASPEED_MCR_INTR_CTRL:
+ case ASPEED_MCR_ADDR_UNREC:
+ case ASPEED_MCR_ADDR_REC:
+ return true;
+ default:
+ return false;
+ }
+}
+
+
+static const struct regmap_config aspeed_edac_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .max_register = ASPEED_MCR_LAST,
+ .reg_write = aspeed_edac_regmap_reg_write,
+ .reg_read = aspeed_edac_regmap_reg_read,
+ .volatile_reg = aspeed_edac_regmap_is_volatile,
+ .fast_io = true,
+};
+
+
+static struct regmap *aspeed_edac_regmap;
+
+
+static void aspeed_edac_count_rec(struct mem_ctl_info *mci,
+ u8 rec_cnt,
+ u32 rec_addr)
+{
+ struct csrow_info *csrow = mci->csrows[0];
+ u32 page, offset, syndrome;
+
+ if (rec_cnt > 0) {
+ /* report first few errors (if there are) */
+ /* note: no addresses are recorded */
+ if (rec_cnt > 1) {
+ page = 0; /* not available */
+ offset = 0; /* not available */
+ syndrome = 0; /* not available */
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
+ rec_cnt-1, page, offset,
+ syndrome, 0, 0, -1,
+ "address(es) not available", "");
+ }
+
+ /* report last error */
+ /* note: rec_addr is the last recoverable error addr */
+ page = rec_addr >> PAGE_SHIFT;
+ offset = rec_addr & ~PAGE_MASK;
+ syndrome = 0; /* not available */
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1,
+ csrow->first_page + page, offset, syndrome,
+ 0, 0, -1, "", "");
+ }
+}
+
+
+static void aspeed_edac_count_un_rec(struct mem_ctl_info *mci,
+ u8 un_rec_cnt,
+ u32 un_rec_addr)
+{
+ struct csrow_info *csrow = mci->csrows[0];
+ u32 page, offset, syndrome;
+
+ if (un_rec_cnt > 0) {
+ /* report 1. error */
+ /* note: un_rec_addr is the first unrecoverable error addr */
+ page = un_rec_addr >> PAGE_SHIFT;
+ offset = un_rec_addr & ~PAGE_MASK;
+ syndrome = 0; /* not available */
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
+ csrow->first_page + page, offset, syndrome,
+ 0, 0, -1, "", "");
+
+ /* report further errors (if there are) */
+ /* note: no addresses are recorded */
+ if (un_rec_cnt > 1) {
+ page = 0; /* not available */
+ offset = 0; /* not available */
+ syndrome = 0; /* not available */
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
+ un_rec_cnt-1, page, offset,
+ syndrome, 0, 0, -1,
+ "address(es) not available", "");
+ }
+ }
+}
+
+
+static void aspeed_edac_enable_interrupts(void)
+{
+
+ regmap_update_bits(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL,
+ ASPEED_MCR_INTR_CTRL_ENABLE,
+ ASPEED_MCR_INTR_CTRL_ENABLE);
+}
+
+
+static void aspeed_edac_disable_interrupts(void)
+{
+ regmap_update_bits(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL,
+ ASPEED_MCR_INTR_CTRL_ENABLE, 0);
+}
+
+
+static void aspeed_edac_clear_interrupts(void)
+{
+ regmap_update_bits(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL,
+ ASPEED_MCR_INTR_CTRL_CLEAR,
+ ASPEED_MCR_INTR_CTRL_CLEAR);
+
+ regmap_update_bits(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL,
+ ASPEED_MCR_INTR_CTRL_CLEAR, 0);
+}
+
+
+static irqreturn_t aspeed_edac_isr(int irq, void *arg)
+{
+ u8 rec_cnt, un_rec_cnt;
+ u32 rec_addr, un_rec_addr;
+ struct mem_ctl_info *mci = arg;
+ u32 reg50, reg5c, reg58;
+
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL, &reg50);
+ dev_dbg(mci->pdev, "received edac interrupt w/ mmc register 50: 0x%x\n",
+ reg50);
+
+ /* collect data about recoverable and unrecoverable errors */
+ rec_cnt = (reg50 & ASPEED_MCR_INTR_CTRL_CNT_REC) >> 16;
+ un_rec_cnt = (reg50 & ASPEED_MCR_INTR_CTRL_CNT_UNREC) >> 12;
+
+ dev_dbg(mci->pdev, "%d recoverable interrupts and %d unrecoverable interrupts\n",
+ rec_cnt, un_rec_cnt);
+
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_ADDR_UNREC, &reg58);
+ un_rec_addr = reg58 >> 4;
+
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_ADDR_REC, &reg5c);
+ rec_addr = reg5c >> 4;
+
+ /* clear interrupt flags and error counters: */
+ aspeed_edac_clear_interrupts();
+
+ /* process recoverable and unrecoverable errors */
+ if (rec_cnt > 0)
+ aspeed_edac_count_rec(mci, rec_cnt, rec_addr);
+
+ if (un_rec_cnt > 0)
+ aspeed_edac_count_un_rec(mci, un_rec_cnt, un_rec_addr);
+
+ if ((rec_cnt == 0) && (un_rec_cnt == 0))
+ dev_dbg(mci->pdev, "received edac interrupt, but did not find any ecc counters\n");
+
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_INTR_CTRL, &reg50);
+ dev_dbg(mci->pdev, "edac interrupt handled. mmc reg 50 is now: 0x%x\n",
+ reg50);
+
+ return IRQ_HANDLED;
+}
+
+
+static int aspeed_edac_config_irq(void *ctx,
+ struct platform_device *pdev)
+{
+ int irq;
+ int rc;
+
+ /* register interrupt handler */
+
+ irq = platform_get_irq(pdev, 0);
+ dev_dbg(&pdev->dev, "got irq %d\n", irq);
+ if (!irq)
+ return -ENODEV;
+
+ rc = devm_request_irq(&pdev->dev, irq, aspeed_edac_isr,
+ IRQF_TRIGGER_HIGH, DRV_NAME, ctx);
+ if (rc) {
+ dev_err(&pdev->dev, "unable to request irq %d\n", irq);
+ return rc;
+ }
+
+ /* enable interrupts */
+ aspeed_edac_enable_interrupts();
+
+ return 0;
+}
+
+
+static int aspeed_edac_init_csrows(struct mem_ctl_info *mci)
+{
+ struct csrow_info *csrow = mci->csrows[0];
+ struct dimm_info *dimm;
+ struct device_node *np;
+ u32 nr_pages, dram_type;
+ struct resource r;
+ u32 reg04;
+ int rc;
+
+ /* retrieve info about physical memory from device tree */
+ np = of_find_node_by_path("/memory");
+
+ if (!np) {
+ dev_err(mci->pdev, "dt: missing /memory node\n");
+ return -ENODEV;
+ };
+
+ rc = of_address_to_resource(np, 0, &r);
+
+ of_node_put(np);
+
+ if (rc) {
+ dev_err(mci->pdev, "dt: failed requesting resource for /memory node\n");
+ return rc;
+ };
+
+ dev_dbg(mci->pdev, "dt: /memory node resources: first page r.start=0x%x, resource_size=0x%x, PAGE_SHIFT macro=0x%x\n",
+ r.start, resource_size(&r), PAGE_SHIFT);
+
+ csrow->first_page = r.start >> PAGE_SHIFT;
+ nr_pages = resource_size(&r) >> PAGE_SHIFT;
+ csrow->last_page = csrow->first_page + nr_pages - 1;
+
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_CONF, &reg04);
+ dram_type = (reg04 & ASPEED_MCR_CONF_DRAM_TYPE) ? MEM_DDR4 : MEM_DDR3;
+
+ dimm = csrow->channels[0]->dimm;
+ dimm->mtype = dram_type;
+ dimm->edac_mode = EDAC_SECDED;
+ dimm->nr_pages = nr_pages / csrow->nr_channels;
+
+ dev_dbg(mci->pdev, "initialized dimm with first_page=0x%lx and nr_pages=0x%x\n",
+ csrow->first_page, nr_pages);
+
+ return 0;
+}
+
+
+static int aspeed_edac_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ void __iomem *regs;
+ struct resource *res;
+ struct mem_ctl_info *mci;
+ struct edac_mc_layer layers[2];
+ struct device_node *np;
+ u32 reg04;
+ int rc;
+
+ /* setup regmap */
+ np = dev->of_node;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENOENT;
+
+ regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(regs))
+ return PTR_ERR(regs);
+
+ aspeed_edac_regmap = devm_regmap_init(dev, NULL, (__force void *)regs,
+ &aspeed_edac_regmap_config);
+ if (IS_ERR(aspeed_edac_regmap))
+ return PTR_ERR(aspeed_edac_regmap);
+
+ /* bail out if ECC mode is not configured */
+ regmap_read(aspeed_edac_regmap, ASPEED_MCR_CONF, &reg04);
+ if (!(reg04 & ASPEED_MCR_CONF_ECC)) {
+ dev_err(&pdev->dev, "ECC mode is not configured in u-boot\n");
+ return -EPERM;
+ }
+
+ edac_op_state = EDAC_OPSTATE_INT;
+
+ /* allocate & init EDAC MC data structure */
+ layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+ layers[0].size = 1;
+ layers[0].is_virt_csrow = true;
+ layers[1].type = EDAC_MC_LAYER_CHANNEL;
+ layers[1].size = 1;
+ layers[1].is_virt_csrow = false;
+
+ mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
+ if (mci == NULL)
+ return -ENOMEM;
+
+ mci->pdev = &pdev->dev;
+ mci->mtype_cap = MEM_FLAG_DDR3 | MEM_FLAG_DDR4;
+ mci->edac_ctl_cap = EDAC_FLAG_SECDED;
+ mci->edac_cap = EDAC_FLAG_SECDED;
+ mci->scrub_cap = SCRUB_FLAG_HW_SRC;
+ mci->scrub_mode = SCRUB_HW_SRC;
+ mci->mod_name = DRV_NAME;
+ mci->ctl_name = "MIC";
+ mci->dev_name = dev_name(&pdev->dev);
+
+ rc = aspeed_edac_init_csrows(mci);
+ if (rc) {
+ dev_err(&pdev->dev, "failed to init csrows\n");
+ goto probe_exit02;
+ }
+
+ platform_set_drvdata(pdev, mci);
+
+ /* register with edac core */
+ rc = edac_mc_add_mc(mci);
+ if (rc) {
+ dev_err(&pdev->dev, "failed to register with EDAC core\n");
+ goto probe_exit02;
+ }
+
+ /* register interrupt handler and enable interrupts */
+ rc = aspeed_edac_config_irq(mci, pdev);
+ if (rc) {
+ dev_err(&pdev->dev, "failed setting up irq\n");
+ goto probe_exit01;
+ }
+
+ return 0;
+
+probe_exit01:
+ edac_mc_del_mc(&pdev->dev);
+probe_exit02:
+ edac_mc_free(mci);
+ return rc;
+}
+
+
+static int aspeed_edac_remove(struct platform_device *pdev)
+{
+ struct mem_ctl_info *mci;
+
+ /* disable interrupts */
+ aspeed_edac_disable_interrupts();
+
+ /* free resources */
+ mci = edac_mc_del_mc(&pdev->dev);
+ if (mci)
+ edac_mc_free(mci);
+
+ return 0;
+}
+
+
+static const struct of_device_id aspeed_edac_of_match[] = {
+ { .compatible = "aspeed,ast2500-sdram-edac" },
+ {},
+};
+
+
+static struct platform_driver aspeed_edac_driver = {
+ .driver = {
+ .name = DRV_NAME,
+ .of_match_table = aspeed_edac_of_match
+ },
+ .probe = aspeed_edac_probe,
+ .remove = aspeed_edac_remove
+};
+
+
+static int __init aspeed_edac_init(void)
+{
+ return platform_driver_register(&aspeed_edac_driver);
+}
+
+
+static void __exit aspeed_edac_exit(void)
+{
+ platform_driver_unregister(&aspeed_edac_driver);
+}
+
+
+module_init(aspeed_edac_init);
+module_exit(aspeed_edac_exit);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Stefan Schaeckeler <sschaeck@xxxxxxxxx>");
+MODULE_DESCRIPTION("Aspeed AST2500 EDAC driver");
+MODULE_VERSION("1.0");
--
2.19.1