These patches add new edac driver for Cadence ddr memory controller.
Cadence controller detects single(CE) and double(UE) bit errors during
memory operations(RMW). DDR controller raised the interrupt on detection
of the ecc error event and fill the data into registers. Driver handle
the interrupt event and notify edac subsystem about ecc errors.
Changes since v4:
=================
- Add Makefile change
- Coreected YAML file fixes
Changes since v3:
=================
- Corrected YAML file location
Changes since v2:
=================
- Added minor fixes to YAML file
- Split ISR into two differnt functions
- Removed unused paramters
- Fixed indentation issues
- Improved code readabilty
- Checked return value for edac_get_dimm
- Modified quirks as a ip_features
Changes since v1:
=================
- Made predefined arrays as static
Fixes: 201447a5db9b ("EDAC/Cadence:Add EDAC driver for cadence memory controller")
- Replace macro 'EDAC_DIMM_PTR' with newly introduce function
- Removed unused variable root*** SUBJECT HERE ***
Dhananjay Kangude (2):
dt-bindings: edac: Add cadence ddr mc support
EDAC/Cadence:Add EDAC driver for cadence memory controller
.../devicetree/bindings/edac/cdns,ddr-edac.yaml | 45 ++
drivers/edac/Kconfig | 8 +
drivers/edac/Makefile | 1 +
drivers/edac/cadence_edac.c | 641 ++++++++++++++++++++
4 files changed, 695 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
create mode 100644 drivers/edac/cadence_edac.c
Add documentation for cadence ddr memory controller EDAC DTS bindings
Signed-off-by: Dhananjay Kangude <[email protected]>
---
.../devicetree/bindings/edac/cdns,ddr-edac.yaml | 45 ++++++++++++++++++++
1 files changed, 45 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
diff --git a/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml b/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
new file mode 100644
index 0000000..198e60d
--- /dev/null
+++ b/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
@@ -0,0 +1,45 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/edac/cdns,ddr-edac.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cadence DDR IP with ECC support (EDAC)
+
+description:
+ This binding describes the Cadence DDR/LPDDR IP with ECC feature enabled
+ to detect and correct CE/UE errors.
+
+maintainers:
+ - Dhananjay Kangdue <[email protected]>
+
+properties:
+ compatible:
+ items:
+ - cdns,ddr4-mc-edac
+
+ reg:
+ items:
+ - description:
+ Register block of DDR/LPDDR apb registers up to mapped area.
+ Mapped area contains the register set for memory controller,
+ phy and PI module register set doesn't part of this mapping.
+
+ interrupts:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+additionalProperties: false
+
+examples:
+ - |
+ edac: edac@fd100000 {
+ compatible = "cdns,ddr4-mc-edac";
+ reg = <0xfd100000 0x4000>;
+ interrupts = <0x00 0x01 0x04>;
+ };
+...
--
1.7.1
Added edac platform driver for Cadence DDR controller which
notify the ecc events based on the single or double bit errors
during memory operations.
Signed-off-by: Dhananjay Kangude <[email protected]>
---
drivers/edac/Kconfig | 8 +
drivers/edac/Makefile | 1 +
drivers/edac/cadence_edac.c | 641 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 650 insertions(+), 0 deletions(-)
create mode 100644 drivers/edac/cadence_edac.c
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index fe2eb89..d5bb399 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -530,4 +530,12 @@ config EDAC_DMC520
Support for error detection and correction on the
SoCs with ARM DMC-520 DRAM controller.
+config EDAC_CADENCE
+ tristate "Candence DDR Memory Controller ECC"
+ depends on ARM
+ help
+ Support for error detection and correction on the Cadence DDR
+ memory controller. The driver reports correctable and uncorrectable
+ memory errors.
+
endif # EDAC
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 269e151..afe043a 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -88,3 +88,4 @@ obj-$(CONFIG_EDAC_QCOM) += qcom_edac.o
obj-$(CONFIG_EDAC_ASPEED) += aspeed_edac.o
obj-$(CONFIG_EDAC_BLUEFIELD) += bluefield_edac.o
obj-$(CONFIG_EDAC_DMC520) += dmc520_edac.o
+obj-$(CONFIG_EDAC_CADENCE) += cadence_edac.o
diff --git a/drivers/edac/cadence_edac.c b/drivers/edac/cadence_edac.c
new file mode 100644
index 0000000..3aecc9a
--- /dev/null
+++ b/drivers/edac/cadence_edac.c
@@ -0,0 +1,641 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cadence DDR4-ECC EDAC Driver.
+ *
+ * Copyright (C) 2019-2020 Cadence Design Systems.
+ *
+ * Authors: Dhananjay Kangude <[email protected]>,
+ */
+
+#include <linux/init.h>
+#include <linux/edac.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include "edac_module.h"
+
+#define CDNS_EDAC_MOD_NAME "cadence-edac"
+#define FORCED_ECC_ERR_EVENT_SUPPORT BIT(1)
+
+/* Granularity of reported error in bytes */
+#define CDNS_EDAC_ERR_GRAIN 1
+
+#define MEM_TYPE_DDR4 0xA
+/* CDNS DDR4 Controller Registers */
+#define DDR_CTL_MEM_TYPE_REG 0x000
+#define DDR_CTL_MEM_WIDTH_REG 0x00c
+#define DDR_CTL_CONTROLLER_BUSY 0x2f0
+
+/* ECC Controller Registers */
+#define ECC_CTL_CONTROL_0_REG 0x254
+#define ECC_CTL_CONTROL_1_REG 0x258
+
+#define ECC_CTL_SCRUB_CONTROL_0 0x280
+#define ECC_CTL_SCRUB_CONTROL_1 0x284
+#define ECC_CTL_SCRUB_CONTROL_2 0x288
+#define ECC_CTL_SCRUB_START_ADDR_L 0x28c
+#define ECC_CTL_SCRUB_START_ADDR_H 0x290
+#define ECC_CTL_SCRUB_END_ADDR_L 0x294
+#define ECC_CTL_SCRUB_END_ADDR_H 0x298
+
+#define ECC_SIG_ECC_C_ADDR_L 0x26c
+#define ECC_SIG_ECC_C_ADDR_H 0x270
+#define ECC_SIG_ECC_C_DATA_L 0x274
+#define ECC_SIG_ECC_C_DATA_H 0x278
+#define ECC_SIG_ECC_C_ID 0x27c
+#define ECC_SIG_ECC_C_SYND 0x270
+#define ECC_SIG_ECC_U_ADDR_L 0x25c
+#define ECC_SIG_ECC_U_ADDR_H 0x25c
+#define ECC_SIG_ECC_U_DATA_L 0x264
+#define ECC_SIG_ECC_U_DATA_H 0x268
+#define ECC_SIG_ECC_U_ID 0x27c
+#define ECC_SIG_ECC_U_SYND 0x260
+
+#define ECC_CTL_INT_STATUS 0x310
+#define ECC_CTL_INT_ACK 0x330
+#define ECC_CTL_INT_MASK 0x350
+
+/* ECC Scrub Macros */
+#define ECC_SCRUB_IN_PROGRESS BIT(8)
+#define ECC_SCRUB_MODE BIT(0)
+#define ECC_SCRUB_START BIT(0)
+#define ECC_SCRUB_LEN_SHIFT (16)
+#define ECC_SCRUB_IDLE_CNT GENMASK(15, 0)
+#define ECC_SCRUB_LEN GENMASK(27, 16)
+#define ECC_CTL_SCRUB_ADDR_L_MASK GENMASK(31, 0)
+#define ECC_CTL_SCRUB_ADDR_H_MASK GENMASK(1, 0)
+
+/* Control register width definitions */
+#define WDTH_16 (2)
+#define WDTH_32 (1)
+#define WDTH_64 (0)
+#define CTL_REG_WIDTH_SHIFT (32)
+#define USER_WORD_SPLIT_WIDTH (8)
+#define CTL_CONTROLLER_BUSY_FLAG BIT(16)
+#define CTL_MEM_MAX_WIDTH_MASK GENMASK(4, 0)
+
+/* ECC Control Macros */
+#define ECC_CTL_FORCE_WC BIT(16)
+#define ECC_CTL_AUTO_CURRUPT_DISABLE BIT(16)
+#define ECC_CTL_AUTO_WRITEBACK_EN BIT(24)
+#define ECC_CTL_ECC_ENABLE GENMASK(9, 8)
+#define ECC_CTL_MTYPE_MASK GENMASK(11, 8)
+#define ECC_CTL_XOR_BITS_MASK GENMASK(15, 0)
+
+/* ECC Status Macros */
+
+/* ECC IRQ Macros */
+#define ECC_INT_CE_EVENT BIT(0)
+#define ECC_INT_SECOND_CE_EVENT BIT(1)
+#define ECC_INT_UE_EVENT BIT(2)
+#define ECC_INT_SECOND_UE_EVENT BIT(3)
+#define ECC_INT_WRITEBACK_UNHANDLED BIT(6)
+#define ECC_INT_SCRUB_DONE BIT(7)
+#define ECC_INT_SCRUB_CE_EVENT BIT(8)
+#define ECC_INT_MASK_ALL_H BIT(8)
+#define ECC_INT_CE_UE_MASK GENMASK(3, 0)
+#define ECC_CE_INTR_MASK GENMASK(1, 0)
+#define ECC_UE_INTR_MASK GENMASK(3, 2)
+#define ECC_CTL_INT_ENABLE_MASK GENMASK(15, 0)
+/* ECC Signature Macros */
+#define ECC_SIG_ECC_C_ID_SHIFT 8
+#define ECC_SIG_ECC_C_SYND_SHIFT 8
+#define ECC_SIG_ECC_C_ADDR_H_MASK GENMASK(1, 0)
+#define ECC_SIG_ECC_C_ID_MASK GENMASK(31, 16)
+#define ECC_SIG_ECC_C_SYND_MASK GENMASK(15, 8)
+
+#define ECC_SIG_ECC_U_ID_SHIFT 0
+#define ECC_SIG_ECC_U_SYND_SHIFT 8
+#define ECC_SIG_ECC_U_ADDR_H_MASK GENMASK(1, 0)
+#define ECC_SIG_ECC_U_ID_MASK GENMASK(15, 0)
+#define ECC_SIG_ECC_U_SYND_MASK GENMASK(15, 8)
+
+/* Syndrome values */
+#define ECC_DOUBLE_MULTI_ERR_SYND 0x03
+
+static char data_synd[] = {
+ 0xf4, 0xf1, 0xec, 0xea, 0xe9, 0xe6, 0xe5, 0xe3,
+ 0xdc, 0xda, 0xd9, 0xd6, 0xd5, 0xd3, 0xce, 0xcb,
+ 0xb5, 0xb0, 0xad, 0xab, 0xa8, 0xa7, 0xa4, 0xa2,
+ 0x9d, 0x9b, 0x98, 0x97, 0x94, 0x92, 0x8f, 0x8a,
+ 0x75, 0x70, 0x6d, 0x6b, 0x68, 0x67, 0x64, 0x62,
+ 0x5e, 0x5b, 0x58, 0x57, 0x54, 0x52, 0x4f, 0x4a,
+ 0x34, 0x31, 0x2c, 0x2a, 0x29, 0x26, 0x25, 0x23,
+ 0x1c, 0x1a, 0x19, 0x16, 0x15, 0x13, 0x0e, 0x0b
+ };
+
+static char check_synd[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};
+
+/**
+ * struct cdns_platform_data - cadence platform data structure.
+ * @ip_features: To differentiate IP features.
+ */
+struct cdns_platform_data {
+ int ip_features;
+};
+
+/**
+ * struct priv_data - edac device private instance data.
+ * @reg: Base address of the DDR controller.
+ * @ce_cnt: Correctable Error count.
+ * @ue_cnt: Uncorrectable Error count.
+ */
+struct priv_data {
+ void __iomem *reg;
+ u32 ce_cnt;
+ u32 ue_cnt;
+#ifdef CONFIG_EDAC_DEBUG
+ struct cdns_platform_data *p;
+#endif
+};
+
+/**
+ * init_mem_layout - Set address Map as per the mc design.
+ * @mci: memory controller information.
+ *
+ * Set Address Map as per mc instance .
+ *
+ * Return: none.
+ */
+static void init_mem_layout(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv = mci->pvt_info;
+ struct csrow_info *csi;
+ struct dimm_info *dimm;
+ struct sysinfo inf;
+ enum mem_type mtype;
+ u32 val, width;
+ u32 size, row;
+ u8 j;
+
+ dimm = edac_get_dimm(mci, 0, 0, 0);
+ if (!dimm) {
+ si_meminfo(&inf);
+ for (row = 0; row < mci->nr_csrows; row++) {
+ csi = mci->csrows[row];
+ size = inf.totalram * inf.mem_unit;
+
+ for (j = 0; j < csi->nr_channels; j++) {
+ dimm = csi->channels[j]->dimm;
+ dimm->edac_mode = EDAC_FLAG_SECDED;
+ /* Get memory type by reading hw registers*/
+ val = readl(priv->reg + DDR_CTL_MEM_TYPE_REG);
+ mtype = val & ECC_CTL_MTYPE_MASK;
+
+ if (mtype == MEM_TYPE_DDR4)
+ dimm->mtype = MEM_DDR4;
+ else
+ dimm->mtype = MEM_EMPTY;
+
+ /*Get EDAC devtype width for the current mc*/
+ width = readl(priv->reg + DDR_CTL_MEM_WIDTH_REG)
+ & CTL_MEM_MAX_WIDTH_MASK;
+ switch (width) {
+ case WDTH_16:
+ dimm->dtype = DEV_X2;
+ break;
+ case WDTH_32:
+ dimm->dtype = DEV_X4;
+ break;
+ case WDTH_64:
+ dimm->dtype = DEV_X8;
+ break;
+ default:
+ dimm->dtype = DEV_UNKNOWN;
+ }
+
+ dimm->nr_pages = (size >> PAGE_SHIFT) /
+ csi->nr_channels;
+ dimm->grain = CDNS_EDAC_ERR_GRAIN;
+ }
+ }
+ }
+}
+
+/**
+ * handle_ce - Handle corrected errors and notify to
+ * edac layer by reading appropriate hw registers
+ * @mci: memory controller information.
+ * Return: void.
+ */
+static void handle_ce(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv;
+ u64 err_c_addr = 0x0;
+ u64 err_c_data = 0x0;
+ u32 err_c_synd, err_c_id;
+ u32 sig_val_l, sig_val_h;
+
+ priv = mci->pvt_info;
+
+ sig_val_l = readl(priv->reg + ECC_SIG_ECC_C_ADDR_L);
+ sig_val_h = (readl(priv->reg + ECC_SIG_ECC_C_ADDR_H) &
+ ECC_SIG_ECC_C_ADDR_H_MASK);
+ err_c_addr = (((err_c_addr | sig_val_h) <<
+ CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ sig_val_l = readl(priv->reg + ECC_SIG_ECC_C_DATA_L);
+ sig_val_h = readl(priv->reg + ECC_SIG_ECC_C_DATA_H);
+ err_c_data = (((err_c_data | sig_val_h) <<
+ CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ err_c_id = ((readl(priv->reg + ECC_SIG_ECC_C_ID) &
+ ECC_SIG_ECC_C_ID_MASK) >>
+ ECC_SIG_ECC_C_ID_SHIFT);
+
+ err_c_synd = ((readl(priv->reg + ECC_SIG_ECC_C_SYND) &
+ ECC_SIG_ECC_C_SYND_MASK) >>
+ ECC_SIG_ECC_C_SYND_SHIFT);
+
+ priv->ce_cnt = priv->ce_cnt + 1;
+
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
+ 1,
+ err_c_addr >> PAGE_SHIFT,
+ err_c_addr & ~PAGE_MASK,
+ err_c_synd, 0, 0, -1,
+ mci->ctl_name, "");
+}
+
+/**
+ * handle_ue - Handle uncorrected errors and notify to
+ * edac layer by reading appropriate hw registers
+ * @mci: memory controller information.
+ * Return: void.
+ */
+static void handle_ue(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv;
+ u64 err_u_addr = 0x0;
+ u64 err_u_data = 0x0;
+ u32 err_u_synd, err_u_id;
+ u32 sig_val_l, sig_val_h;
+
+ priv = mci->pvt_info;
+ sig_val_l = readl(priv->reg + ECC_SIG_ECC_U_ADDR_L);
+ sig_val_h = (readl(priv->reg + ECC_SIG_ECC_U_ADDR_H) &
+ ECC_SIG_ECC_U_ADDR_H_MASK);
+ err_u_addr = (((err_u_addr | sig_val_h) <<
+ CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ sig_val_l = readl(priv->reg + ECC_SIG_ECC_U_DATA_L);
+ sig_val_h = readl(priv->reg + ECC_SIG_ECC_U_DATA_H);
+ err_u_data = (((err_u_data | sig_val_h) <<
+ CTL_REG_WIDTH_SHIFT) | sig_val_l);
+
+ err_u_id = ((readl(priv->reg + ECC_SIG_ECC_U_ID) &
+ ECC_SIG_ECC_U_ID_MASK) >>
+ ECC_SIG_ECC_U_ID_SHIFT);
+
+ err_u_synd = ((readl(priv->reg + ECC_SIG_ECC_U_SYND) &
+ ECC_SIG_ECC_U_SYND_MASK) >>
+ ECC_SIG_ECC_U_SYND_SHIFT);
+ priv->ue_cnt = priv->ue_cnt + 1;
+
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
+ 1,
+ err_u_addr >> PAGE_SHIFT,
+ err_u_addr & ~PAGE_MASK,
+ err_u_synd, 0, 0, -1,
+ mci->ctl_name, "");
+}
+
+/**
+ * edac_ecc_isr - Interrupt Handler for ECC interrupts.
+ * @irq: IRQ number.
+ * @dev_id: Device ID.
+ *
+ * Return: IRQ_NONE, if interrupt not set or IRQ_HANDLED otherwise.
+ */
+static irqreturn_t edac_ecc_isr(int irq, void *dev_id)
+{
+ struct mem_ctl_info *mci = dev_id;
+ struct priv_data *priv;
+ u32 intr_status;
+ u32 val;
+
+ priv = mci->pvt_info;
+
+ /* Check the intr status and confirm ECC error intr */
+ intr_status = readl(priv->reg + ECC_CTL_INT_STATUS);
+
+ edac_dbg(3, "InterruptStatus : 0x%x\n", intr_status);
+ val = intr_status & (ECC_INT_CE_UE_MASK);
+ if (!((val & ECC_CE_INTR_MASK) || (val & ECC_UE_INTR_MASK)))
+ return IRQ_NONE;
+
+ if (val & ECC_CE_INTR_MASK) {
+ handle_ce(mci);
+
+ /* Clear the interrupt source */
+ if (val & ECC_INT_CE_EVENT)
+ writel(ECC_INT_CE_EVENT, priv->reg + ECC_CTL_INT_ACK);
+ else if (val & ECC_INT_SECOND_CE_EVENT)
+ writel(ECC_INT_SECOND_CE_EVENT,
+ priv->reg + ECC_CTL_INT_ACK);
+ else
+ edac_printk(KERN_ERR, EDAC_MC, "Failed to clear IRQ\n");
+ }
+
+ if (val & ECC_UE_INTR_MASK) {
+ handle_ue(mci);
+
+ /* Clear the interrupt source */
+ if (val & ECC_INT_UE_EVENT)
+ writel(ECC_INT_UE_EVENT, priv->reg + ECC_CTL_INT_ACK);
+ else if (val & ECC_INT_SECOND_UE_EVENT)
+ writel(ECC_INT_SECOND_UE_EVENT,
+ priv->reg + ECC_CTL_INT_ACK);
+ else
+ edac_printk(KERN_ERR, EDAC_MC, "Failed to clear IRQ\n");
+ }
+
+ edac_dbg(3, "Total error count CE %d UE %d\n",
+ priv->ce_cnt, priv->ue_cnt);
+
+ return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_EDAC_DEBUG
+/**
+ * forced_ecc_error_show/store - Sysfs atrribute functions.
+ * @dev: Pointer to device structure.
+ * @mattr: Pointer to device attributes.
+ * @data : Data send by User space and stored in file.
+ * Return: as SUCCESS,Total number of characters written otherwise
+ * negative value.
+ */
+static ssize_t forced_ecc_error_show(struct device *dev,
+ struct device_attribute *mattr,
+ char *data)
+{
+ return sprintf(data, "CDNS-DDR4 Force Injection Help:\n"
+ "CE/UE: Corrected/Uncorrected\n"
+ "checkcode/data:source\n"
+ "user_word [0-1]:subpart of data\n"
+ "bit [0-31]:bit number\n");
+}
+
+static ssize_t forced_ecc_error_store(struct device *dev,
+ struct device_attribute *mattr,
+ const char *data, size_t count)
+{
+ struct mem_ctl_info *mci = to_mci(dev);
+ struct priv_data *priv = mci->pvt_info;
+ int args_cnt;
+ int ret;
+ char **args;
+ u32 regval;
+ u8 user_word;
+ u8 bit_no;
+
+ /* Split string buffer into separate parameters */
+ args = argv_split(GFP_KERNEL, data, &args_cnt);
+
+ ret = kstrtou8(args[2], 0, &user_word);
+ if (ret)
+ return ret;
+
+ ret = kstrtou8(args[3], 0, &bit_no);
+ if (ret)
+ return ret;
+
+ /* Check ecc enabled */
+ if (!readl(priv->reg + ECC_CTL_CONTROL_0_REG) & ECC_CTL_ECC_ENABLE)
+ return count;
+
+ /* Check no write operation pending to controller*/
+ while (readl(priv->reg + DDR_CTL_CONTROLLER_BUSY) &
+ CTL_CONTROLLER_BUSY_FLAG) {
+ usleep_range(1000, 10000);
+ }
+
+ /* Write appropriate syndrome to xor_check_bit*/
+ if (!strcmp(args[0], "CE")) {
+ if (!strcmp(args[1], "checkcode")) {
+ regval = readl(priv->reg + ECC_CTL_CONTROL_1_REG);
+ regval = (regval & ~(ECC_CTL_XOR_BITS_MASK)) |
+ (check_synd[bit_no] <<
+ (USER_WORD_SPLIT_WIDTH * user_word));
+ writel(regval, priv->reg + ECC_CTL_CONTROL_1_REG);
+ } else if (!strcmp(args[1], "data")) {
+ regval = readl(priv->reg + ECC_CTL_CONTROL_1_REG);
+ regval = (regval & ~(ECC_CTL_XOR_BITS_MASK)) |
+ (data_synd[bit_no] <<
+ (USER_WORD_SPLIT_WIDTH * user_word));
+ writel(regval, priv->reg + ECC_CTL_CONTROL_1_REG);
+ }
+ /* Enable the ECC writeback_en for corrected error */
+ regval = readl(priv->reg + ECC_CTL_CONTROL_1_REG);
+ writel((regval | ECC_CTL_AUTO_WRITEBACK_EN),
+ priv->reg + ECC_CTL_CONTROL_1_REG);
+ } else if (!strcmp(args[0], "UE")) {
+ writel(ECC_DOUBLE_MULTI_ERR_SYND,
+ priv->reg + ECC_CTL_CONTROL_1_REG);
+ }
+
+ /* Assert fwc */
+ writel((ECC_CTL_FORCE_WC | readl(priv->reg + ECC_CTL_CONTROL_0_REG)),
+ priv->reg + ECC_CTL_CONTROL_0_REG);
+ return count;
+}
+
+static DEVICE_ATTR_RW(forced_ecc_error);
+static int create_sysfs_attributes(struct mem_ctl_info *mci)
+{
+ int rc;
+
+ rc = device_create_file(&mci->dev, &dev_attr_forced_ecc_error);
+ if (rc < 0)
+ return rc;
+ return 0;
+}
+
+static void remove_sysfs_attributes(struct mem_ctl_info *mci)
+{
+ device_remove_file(&mci->dev, &dev_attr_forced_ecc_error);
+}
+
+#endif
+
+static const struct cdns_platform_data cdns_edac = {
+#ifdef CONFIG_EDAC_DEBUG
+ .ip_features = FORCED_ECC_ERR_EVENT_SUPPORT,
+#endif
+};
+
+static const struct of_device_id cdns_edac_of_match[] = {
+ { .compatible = "cdns,ddr4-mc-edac", .data = &cdns_edac },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, cdns_edac_of_match);
+
+/**
+ * cdns_edac_mc_probe - bind cdns mc controller driver to framework.
+ * @pdev: platform device.
+ *
+ * Probe a memory controller for binding with the driver.
+ *
+ * Return: 0 if binding of the controller instance is successful;
+ * otherwise, < 0 on error.
+ */
+static int cdns_edac_mc_probe(struct platform_device *pdev)
+{
+#ifdef CONFIG_EDAC_DEBUG
+ const struct cdns_platform_data *p;
+#endif
+ struct device *dev = &pdev->dev;
+ struct edac_mc_layer layers[1];
+ const struct of_device_id *id;
+ struct priv_data *priv_data;
+ struct mem_ctl_info *mci;
+ struct resource *res;
+ void __iomem *reg;
+ int ret = -ENODEV;
+ int irq;
+
+ id = of_match_device(cdns_edac_of_match, &pdev->dev);
+ if (!id)
+ return -ENODEV;
+
+#ifdef CONFIG_EDAC_DEBUG
+ p = of_device_get_match_data(&pdev->dev);
+ if (!p)
+ return -ENODEV;
+#endif
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ reg = devm_ioremap_resource(dev, res);
+ if (IS_ERR(reg)) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "cdns DDR4 mc regs are not defined\n");
+ return PTR_ERR(reg);
+ }
+
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "IO mapped reg addr: %p\n", reg);
+ layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
+ layers[0].size = 1;
+ layers[0].is_virt_csrow = true;
+
+ mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
+ sizeof(struct priv_data));
+ if (!mci) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "Failed memory allocation for mc instance\n");
+ return -ENOMEM;
+ }
+ mci->pdev = &pdev->dev;
+ priv_data = mci->pvt_info;
+ priv_data->reg = reg;
+ priv_data->ce_cnt = 0;
+ priv_data->ue_cnt = 0;
+ platform_set_drvdata(pdev, mci);
+ /* Initialize controller capabilities */
+ mci->mtype_cap = MEM_FLAG_DDR4;
+ mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
+ mci->scrub_cap = SCRUB_UNKNOWN;
+ mci->scrub_mode = SCRUB_HW_PROG;
+ mci->edac_cap = EDAC_FLAG_SECDED;
+ mci->ctl_name = id->compatible;
+ mci->dev_name = dev_name(&pdev->dev);
+ mci->mod_name = CDNS_EDAC_MOD_NAME;
+ mci->ctl_page_to_phys = NULL;
+
+ /* Interrupt feature is supported by cadence mc */
+ edac_op_state = EDAC_OPSTATE_INT;
+ init_mem_layout(mci);
+
+ /* Setup Interrupt handler for ECC */
+ irq = platform_get_irq(pdev, 0);
+ if (!irq) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "irq number not defined for ECC.\n");
+ goto err;
+ }
+ ret = devm_request_irq(dev, irq, edac_ecc_isr, 0,
+ "cdns-edac-mc-ecc-irq", mci);
+ if (ret) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "request_irq fail for CDNS_EDAC irq\n");
+ goto err;
+ }
+ ret = edac_mc_add_mc(mci);
+ if (ret) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "Failed to register with EDAC core\n");
+ goto err;
+ }
+
+#ifdef CONFIG_EDAC_DEBUG
+ if (p->ip_features & FORCED_ECC_ERR_EVENT_SUPPORT) {
+ if (create_sysfs_attributes(mci)) {
+ edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME,
+ "Failed to create sysfs entries\n");
+ goto err1;
+ }
+ }
+#endif
+ /* Enable & set CE/UE Interrupts for DDR4 Controller */
+ writel((unsigned int)(~(ECC_CTL_INT_ENABLE_MASK)),
+ priv_data->reg + ECC_CTL_INT_MASK);
+
+ /* Start capturing the correctable and uncorrectable errors.
+ * Write 1 to enable.
+ */
+ writel(ECC_CTL_ECC_ENABLE, priv_data->reg + ECC_CTL_CONTROL_0_REG);
+ return 0;
+
+err1:
+ edac_mc_del_mc(&pdev->dev);
+
+err:
+ edac_mc_free(mci);
+ return ret;
+}
+
+/**
+ * cdns_edac_mc_remove - Unbind driver from controller.
+ * @pdev: Platform device.
+ *
+ * Return: 0
+ */
+static int cdns_edac_mc_remove(struct platform_device *pdev)
+{
+ struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+ struct priv_data *priv = mci->pvt_info;
+
+ /* Disable All ECC Interrupts for DDR4 Controller */
+ writel(ECC_CTL_INT_ENABLE_MASK, priv->reg + ECC_CTL_INT_MASK);
+
+ /* Disable ecc feature before removing driver by writing 0 */
+ writel((unsigned int)(~(ECC_CTL_ECC_ENABLE)),
+ priv->reg + ECC_CTL_CONTROL_0_REG);
+
+#ifdef CONFIG_EDAC_DEBUG
+ remove_sysfs_attributes(mci);
+#endif
+ edac_mc_del_mc(&pdev->dev);
+ edac_mc_free(mci);
+
+ return 0;
+}
+
+static struct platform_driver cdns_edac_mc_driver = {
+ .driver = {
+ .name = "cadence-edac",
+ .of_match_table = cdns_edac_of_match,
+ },
+ .probe = cdns_edac_mc_probe,
+ .remove = cdns_edac_mc_remove,
+};
+
+module_platform_driver(cdns_edac_mc_driver);
+
+MODULE_AUTHOR("Cadence");
+MODULE_DESCRIPTION("Cadence DDR4 Controller ECC driver");
+MODULE_LICENSE("GPL v2");
--
1.7.1
On Fri, 24 Apr 2020 10:31:54 +0200, Dhananjay Kangude wrote:
> Add documentation for cadence ddr memory controller EDAC DTS bindings
>
> Signed-off-by: Dhananjay Kangude <[email protected]>
> ---
> .../devicetree/bindings/edac/cdns,ddr-edac.yaml | 45 ++++++++++++++++++++
> 1 files changed, 45 insertions(+), 0 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
>
My bot found errors running 'make dt_binding_check' on your patch:
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml: properties:compatible:items: ['cdns,ddr4-mc-edac'] is not valid under any of the given schemas (Possible causes of the failure):
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml: properties:compatible:items: ['cdns,ddr4-mc-edac'] is not of type 'object', 'boolean'
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml: properties:compatible:items:0: 'cdns,ddr4-mc-edac' is not of type 'object', 'boolean'
Documentation/devicetree/bindings/Makefile:11: recipe for target 'Documentation/devicetree/bindings/edac/cdns,ddr-edac.example.dts' failed
make[1]: *** [Documentation/devicetree/bindings/edac/cdns,ddr-edac.example.dts] Error 1
make[1]: *** Waiting for unfinished jobs....
warning: no schema found in file: Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml: ignoring, error in schema: properties: compatible: items
warning: no schema found in file: Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml
/builds/robherring/linux-dt-review/Documentation/devicetree/bindings/edac/cdns,ddr-edac.yaml: ignoring, error in schema: properties: compatible: items
Makefile:1300: recipe for target 'dt_binding_check' failed
make: *** [dt_binding_check] Error 2
See https://patchwork.ozlabs.org/patch/1276250
If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure dt-schema is up to date:
pip3 install git+https://github.com/devicetree-org/dt-schema.git@master --upgrade
Please check and re-submit.
Hi Dhananjay,
On 24/04/2020 09:31, Dhananjay Kangude wrote:
> Added edac platform driver for Cadence DDR controller which
> notify the ecc events based on the single or double bit errors
> during memory operations.
Is there any public documentation for this device?
The way you're using syfs here is a problem. Surely this compile time debug option for
error injection is only going to get used by Soc integrators?, not by people with
platforms that have this device...
Its going to be much simpler to remove it.
> diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
> index fe2eb89..d5bb399 100644
> --- a/drivers/edac/Kconfig
> +++ b/drivers/edac/Kconfig
> @@ -530,4 +530,12 @@ config EDAC_DMC520
> Support for error detection and correction on the
> SoCs with ARM DMC-520 DRAM controller.
>
> +config EDAC_CADENCE
> + tristate "Candence DDR Memory Controller ECC"
Typo: ^^
> + depends on ARM
> + help
> + Support for error detection and correction on the Cadence DDR
> + memory controller. The driver reports correctable and uncorrectable
> + memory errors.
> +
> endif # EDAC
> diff --git a/drivers/edac/cadence_edac.c b/drivers/edac/cadence_edac.c
> new file mode 100644
> index 0000000..3aecc9a
> --- /dev/null
> +++ b/drivers/edac/cadence_edac.c
> @@ -0,0 +1,641 @@
> +#include <linux/init.h>
> +#include <linux/edac.h>
> +#include <linux/io.h>
> +#include <linux/interrupt.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/module.h>
> +#include <linux/uaccess.h>
> +#include <linux/delay.h>
> +#include "edac_module.h"
> +
> +#define CDNS_EDAC_MOD_NAME "cadence-edac"
> +#define FORCED_ECC_ERR_EVENT_SUPPORT BIT(1)
> +
> +/* Granularity of reported error in bytes */
> +#define CDNS_EDAC_ERR_GRAIN 1
> +
> +#define MEM_TYPE_DDR4 0xA
> +/* CDNS DDR4 Controller Registers */
> +#define DDR_CTL_MEM_TYPE_REG 0x000
> +#define DDR_CTL_MEM_WIDTH_REG 0x00c
> +#define DDR_CTL_CONTROLLER_BUSY 0x2f0
> +
> +/* ECC Controller Registers */
> +#define ECC_CTL_CONTROL_0_REG 0x254
> +#define ECC_CTL_CONTROL_1_REG 0x258
> +
> +#define ECC_CTL_SCRUB_CONTROL_0 0x280
> +#define ECC_CTL_SCRUB_CONTROL_1 0x284
> +#define ECC_CTL_SCRUB_CONTROL_2 0x288
> +#define ECC_CTL_SCRUB_START_ADDR_L 0x28c
> +#define ECC_CTL_SCRUB_START_ADDR_H 0x290
> +#define ECC_CTL_SCRUB_END_ADDR_L 0x294
> +#define ECC_CTL_SCRUB_END_ADDR_H 0x298
> +
> +#define ECC_SIG_ECC_C_ADDR_L 0x26c
> +#define ECC_SIG_ECC_C_ADDR_H 0x270
> +#define ECC_SIG_ECC_C_DATA_L 0x274
> +#define ECC_SIG_ECC_C_DATA_H 0x278
> +#define ECC_SIG_ECC_C_ID 0x27c
> +#define ECC_SIG_ECC_C_SYND 0x270
> +#define ECC_SIG_ECC_U_ADDR_L 0x25c
> +#define ECC_SIG_ECC_U_ADDR_H 0x25c
> +#define ECC_SIG_ECC_U_DATA_L 0x264
> +#define ECC_SIG_ECC_U_DATA_H 0x268
> +#define ECC_SIG_ECC_U_ID 0x27c
> +#define ECC_SIG_ECC_U_SYND 0x260
> +
> +#define ECC_CTL_INT_STATUS 0x310
> +#define ECC_CTL_INT_ACK 0x330
> +#define ECC_CTL_INT_MASK 0x350
> +
> +/* ECC Scrub Macros */
> +#define ECC_SCRUB_IN_PROGRESS BIT(8)
> +#define ECC_SCRUB_MODE BIT(0)
> +#define ECC_SCRUB_START BIT(0)
> +#define ECC_SCRUB_LEN_SHIFT (16)
> +#define ECC_SCRUB_IDLE_CNT GENMASK(15, 0)
> +#define ECC_SCRUB_LEN GENMASK(27, 16)
> +#define ECC_CTL_SCRUB_ADDR_L_MASK GENMASK(31, 0)
> +#define ECC_CTL_SCRUB_ADDR_H_MASK GENMASK(1, 0)
> +
> +/* Control register width definitions */
> +#define WDTH_16 (2)
> +#define WDTH_32 (1)
> +#define WDTH_64 (0)
> +#define CTL_REG_WIDTH_SHIFT (32)
> +#define USER_WORD_SPLIT_WIDTH (8)
> +#define CTL_CONTROLLER_BUSY_FLAG BIT(16)
> +#define CTL_MEM_MAX_WIDTH_MASK GENMASK(4, 0)
> +
> +/* ECC Control Macros */
> +#define ECC_CTL_FORCE_WC BIT(16)
> +#define ECC_CTL_AUTO_CURRUPT_DISABLE BIT(16)
> +#define ECC_CTL_AUTO_WRITEBACK_EN BIT(24)
> +#define ECC_CTL_ECC_ENABLE GENMASK(9, 8)
> +#define ECC_CTL_MTYPE_MASK GENMASK(11, 8)
> +#define ECC_CTL_XOR_BITS_MASK GENMASK(15, 0)
> +
> +/* ECC Status Macros */
> +
> +/* ECC IRQ Macros */
> +#define ECC_INT_CE_EVENT BIT(0)
> +#define ECC_INT_SECOND_CE_EVENT BIT(1)
> +#define ECC_INT_UE_EVENT BIT(2)
> +#define ECC_INT_SECOND_UE_EVENT BIT(3)
> +#define ECC_INT_WRITEBACK_UNHANDLED BIT(6)
> +#define ECC_INT_SCRUB_DONE BIT(7)
> +#define ECC_INT_SCRUB_CE_EVENT BIT(8)
> +#define ECC_INT_MASK_ALL_H BIT(8)
> +#define ECC_INT_CE_UE_MASK GENMASK(3, 0)
> +#define ECC_CE_INTR_MASK GENMASK(1, 0)
> +#define ECC_UE_INTR_MASK GENMASK(3, 2)
> +#define ECC_CTL_INT_ENABLE_MASK GENMASK(15, 0)
> +/* ECC Signature Macros */
> +#define ECC_SIG_ECC_C_ID_SHIFT 8
Sure?
> +#define ECC_SIG_ECC_C_SYND_SHIFT 8
> +#define ECC_SIG_ECC_C_ADDR_H_MASK GENMASK(1, 0)
> +#define ECC_SIG_ECC_C_ID_MASK GENMASK(31, 16)
> +#define ECC_SIG_ECC_C_SYND_MASK GENMASK(15, 8)
> +
> +#define ECC_SIG_ECC_U_ID_SHIFT 0
> +#define ECC_SIG_ECC_U_SYND_SHIFT 8
> +#define ECC_SIG_ECC_U_ADDR_H_MASK GENMASK(1, 0)
> +#define ECC_SIG_ECC_U_ID_MASK GENMASK(15, 0)
> +#define ECC_SIG_ECC_U_SYND_MASK GENMASK(15, 8)
> +
> +/* Syndrome values */
> +#define ECC_DOUBLE_MULTI_ERR_SYND 0x03
> +
> +static char data_synd[] = {
> + 0xf4, 0xf1, 0xec, 0xea, 0xe9, 0xe6, 0xe5, 0xe3,
> + 0xdc, 0xda, 0xd9, 0xd6, 0xd5, 0xd3, 0xce, 0xcb,
> + 0xb5, 0xb0, 0xad, 0xab, 0xa8, 0xa7, 0xa4, 0xa2,
> + 0x9d, 0x9b, 0x98, 0x97, 0x94, 0x92, 0x8f, 0x8a,
> + 0x75, 0x70, 0x6d, 0x6b, 0x68, 0x67, 0x64, 0x62,
> + 0x5e, 0x5b, 0x58, 0x57, 0x54, 0x52, 0x4f, 0x4a,
> + 0x34, 0x31, 0x2c, 0x2a, 0x29, 0x26, 0x25, 0x23,
> + 0x1c, 0x1a, 0x19, 0x16, 0x15, 0x13, 0x0e, 0x0b
> + };
> +
> +static char check_synd[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};
(you use these with a user controlled value and no bounds checking.
But I'm not convinced this error injection is going to get used upstream, and I don't
think you can use sysfs to move argv[] around!).
> +/**
> + * struct cdns_platform_data - cadence platform data structure.
> + * @ip_features: To differentiate IP features.
> + */
> +struct cdns_platform_data {
> + int ip_features;
> +};
You only read/write a constant value if CONFIG_EDAC_DEBUG is defined.
Isn't this struct redundant?
> +
> +/**
> + * struct priv_data - edac device private instance data.
> + * @reg: Base address of the DDR controller.
> + * @ce_cnt: Correctable Error count.
> + * @ue_cnt: Uncorrectable Error count.
> + */
> +struct priv_data {
> + void __iomem *reg;
> + u32 ce_cnt;
> + u32 ue_cnt;
edac exists to provide these counters. Please don't duplicate them for a debug message
no-one will ever see.
> +#ifdef CONFIG_EDAC_DEBUG
> + struct cdns_platform_data *p;
> +#endif
Isn't this struct redundant?
> +};
> +
> +/**
> + * init_mem_layout - Set address Map as per the mc design.
> + * @mci: memory controller information.
> + *
> + * Set Address Map as per mc instance .
> + *
> + * Return: none.
> + */
> +static void init_mem_layout(struct mem_ctl_info *mci)
> +{
> + struct priv_data *priv = mci->pvt_info;
> + struct csrow_info *csi;
> + struct dimm_info *dimm;
> + struct sysinfo inf;
> + enum mem_type mtype;
> + u32 val, width;
> + u32 size, row;
> + u8 j;
> +
> + dimm = edac_get_dimm(mci, 0, 0, 0);
> + if (!dimm) {
Returning 'if (dimm)' would avoid some indenting here.
But can this actually happen?
From the one caller we know this will return the dimm allocated by edac_mc_alloc_dimms().
You have one layer, of size 1. My reading of edac_mc_alloc() gives tot_dimms = 1, and
tot_csrows = 1... in what circumstances does this code run?
> + si_meminfo(&inf);
> + for (row = 0; row < mci->nr_csrows; row++) {
> + csi = mci->csrows[row];
> + size = inf.totalram * inf.mem_unit;
> +
> + for (j = 0; j < csi->nr_channels; j++) {
> + dimm = csi->channels[j]->dimm;
> + dimm->edac_mode = EDAC_FLAG_SECDED;
> + /* Get memory type by reading hw registers*/
> + val = readl(priv->reg + DDR_CTL_MEM_TYPE_REG);
> + mtype = val & ECC_CTL_MTYPE_MASK;
> +
> + if (mtype == MEM_TYPE_DDR4)
> + dimm->mtype = MEM_DDR4;
> + else
> + dimm->mtype = MEM_EMPTY;
> +
> + /*Get EDAC devtype width for the current mc*/
> + width = readl(priv->reg + DDR_CTL_MEM_WIDTH_REG)
> + & CTL_MEM_MAX_WIDTH_MASK;
> + switch (width) {
> + case WDTH_16:
> + dimm->dtype = DEV_X2;
> + break;
> + case WDTH_32:
> + dimm->dtype = DEV_X4;
> + break;
> + case WDTH_64:
> + dimm->dtype = DEV_X8;
> + break;
> + default:
> + dimm->dtype = DEV_UNKNOWN;
> + }
> + dimm->nr_pages = (size >> PAGE_SHIFT) /
> + csi->nr_channels;
> + dimm->grain = CDNS_EDAC_ERR_GRAIN;
> + }
> + }
> + }
> +}
> +
> +/**
> + * handle_ce - Handle corrected errors and notify to
> + * edac layer by reading appropriate hw registers
> + * @mci: memory controller information.
> + * Return: void.
> + */
> +static void handle_ce(struct mem_ctl_info *mci)
> +{
> + struct priv_data *priv;
> + u64 err_c_addr = 0x0;
> + u64 err_c_data = 0x0;
> + u32 err_c_synd, err_c_id;
> + u32 sig_val_l, sig_val_h;
> +
> + priv = mci->pvt_info;
> +
> + sig_val_l = readl(priv->reg + ECC_SIG_ECC_C_ADDR_L);
> + sig_val_h = (readl(priv->reg + ECC_SIG_ECC_C_ADDR_H) &
> + ECC_SIG_ECC_C_ADDR_H_MASK);
> + err_c_addr = (((err_c_addr | sig_val_h) <<
> + CTL_REG_WIDTH_SHIFT) | sig_val_l);
err_c_addr was initialised to 0,... isn't this the same as:
| err_c_addr = (sig_val_h << CTL_REG_WIDTH_SHIFT) | sig_val_l;
> + sig_val_l = readl(priv->reg + ECC_SIG_ECC_C_DATA_L);
> + sig_val_h = readl(priv->reg + ECC_SIG_ECC_C_DATA_H);
> + err_c_data = (((err_c_data | sig_val_h) <<
> + CTL_REG_WIDTH_SHIFT) | sig_val_l);
err_c_data was initialised to 0....
> + err_c_id = ((readl(priv->reg + ECC_SIG_ECC_C_ID) &
> + ECC_SIG_ECC_C_ID_MASK) >>
> + ECC_SIG_ECC_C_ID_SHIFT);
Would the FIELD_GET() macros make this clearer?
| FIELD_GET(ECC_SIG_ECC_C_ID_MASK, readl(priv->reg + ECC_SIG_ECC_C_ID));
> + err_c_synd = ((readl(priv->reg + ECC_SIG_ECC_C_SYND) &
> + ECC_SIG_ECC_C_SYND_MASK) >>
> + ECC_SIG_ECC_C_SYND_SHIFT);
FIELD_GET()?
> +
> + priv->ce_cnt = priv->ce_cnt + 1;
Please don't duplicate edac for debug messages.
> + edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
> + 1,
> + err_c_addr >> PAGE_SHIFT,
> + err_c_addr & ~PAGE_MASK,
> + err_c_synd, 0, 0, -1,
> + mci->ctl_name, "");
> +}
> +
> +/**
> + * handle_ue - Handle uncorrected errors and notify to
> + * edac layer by reading appropriate hw registers
> + * @mci: memory controller information.
> + * Return: void.
> + */
> +static void handle_ue(struct mem_ctl_info *mci)
> +{
[as above]
> +}
> +
> +/**
> + * edac_ecc_isr - Interrupt Handler for ECC interrupts.
> + * @irq: IRQ number.
> + * @dev_id: Device ID.
> + *
> + * Return: IRQ_NONE, if interrupt not set or IRQ_HANDLED otherwise.
> + */
> +static irqreturn_t edac_ecc_isr(int irq, void *dev_id)
> +{
> + struct mem_ctl_info *mci = dev_id;
> + struct priv_data *priv;
> + u32 intr_status;
> + u32 val;
> +
> + priv = mci->pvt_info;
> +
> + /* Check the intr status and confirm ECC error intr */
> + intr_status = readl(priv->reg + ECC_CTL_INT_STATUS);
> +
> + edac_dbg(3, "InterruptStatus : 0x%x\n", intr_status);
> + val = intr_status & (ECC_INT_CE_UE_MASK);
> + if (!((val & ECC_CE_INTR_MASK) || (val & ECC_UE_INTR_MASK)))
| if (!val)
?
> + return IRQ_NONE;
> + if (val & ECC_CE_INTR_MASK) {
> + handle_ce(mci);
> +
> + /* Clear the interrupt source */
> + if (val & ECC_INT_CE_EVENT)
> + writel(ECC_INT_CE_EVENT, priv->reg + ECC_CTL_INT_ACK);
> + else if (val & ECC_INT_SECOND_CE_EVENT)
> + writel(ECC_INT_SECOND_CE_EVENT,
> + priv->reg + ECC_CTL_INT_ACK);
> + else
> + edac_printk(KERN_ERR, EDAC_MC, "Failed to clear IRQ\n");
Please ensure this is rate limited!
> + }
> +
> + if (val & ECC_UE_INTR_MASK) {
> + handle_ue(mci);
> +
> + /* Clear the interrupt source */
> + if (val & ECC_INT_UE_EVENT)
> + writel(ECC_INT_UE_EVENT, priv->reg + ECC_CTL_INT_ACK);
> + else if (val & ECC_INT_SECOND_UE_EVENT)
> + writel(ECC_INT_SECOND_UE_EVENT,
> + priv->reg + ECC_CTL_INT_ACK);
> + else
> + edac_printk(KERN_ERR, EDAC_MC, "Failed to clear IRQ\n");
Please ensure this is rate limited!
> + }
> +
> + edac_dbg(3, "Total error count CE %d UE %d\n",
> + priv->ce_cnt, priv->ue_cnt);
> +
> + return IRQ_HANDLED;
> +}
> +
> +#ifdef CONFIG_EDAC_DEBUG
> +/**
> + * forced_ecc_error_show/store - Sysfs atrribute functions.
> + * @dev: Pointer to device structure.
> + * @mattr: Pointer to device attributes.
> + * @data : Data send by User space and stored in file.
> + * Return: as SUCCESS,Total number of characters written otherwise
> + * negative value.
> + */
> +static ssize_t forced_ecc_error_show(struct device *dev,
> + struct device_attribute *mattr,
> + char *data)
> +{
> + return sprintf(data, "CDNS-DDR4 Force Injection Help:\n"
> + "CE/UE: Corrected/Uncorrected\n"
> + "checkcode/data:source\n"
> + "user_word [0-1]:subpart of data\n"
> + "bit [0-31]:bit number\n");
Multiple values, and multiple lines in sysfs are, frowned on. There is a
"one value per sysfs file" rule:
https://lore.kernel.org/linux-pci/[email protected]/
(the attributes section in 'Documentation/filesystems/sysfs.rst' also has some stuff on this)
Its not clear to me from this help text what I'd have to write in here to inject an error.
This is for debug? Who is expected to use it? Is it really needed upstream?
Can we remove this #ifdeffery and heavily-frowned-on use of sysfs? You are abusing it to
move an argv[] into the kernel.
> +static const struct of_device_id cdns_edac_of_match[] = {
> + { .compatible = "cdns,ddr4-mc-edac", .data = &cdns_edac },
> + {},
> +};
> +
> +MODULE_DEVICE_TABLE(of, cdns_edac_of_match);
> +/**
> + * cdns_edac_mc_probe - bind cdns mc controller driver to framework.
> + * @pdev: platform device.
> + *
> + * Probe a memory controller for binding with the driver.
> + *
> + * Return: 0 if binding of the controller instance is successful;
> + * otherwise, < 0 on error.
> + */
> +static int cdns_edac_mc_probe(struct platform_device *pdev)
> +{
[...]
> + /* Enable & set CE/UE Interrupts for DDR4 Controller */
> + writel((unsigned int)(~(ECC_CTL_INT_ENABLE_MASK)),
> + priv_data->reg + ECC_CTL_INT_MASK);
> +
> + /* Start capturing the correctable and uncorrectable errors.
> + * Write 1 to enable.
> + */
> + writel(ECC_CTL_ECC_ENABLE, priv_data->reg + ECC_CTL_CONTROL_0_REG);
> + return 0;
> +
> +err1:
(giving these names will make the code more readable)
> + edac_mc_del_mc(&pdev->dev);
> +
> +err:
> + edac_mc_free(mci);
> + return ret;
> +}
> +
> +/**
> + * cdns_edac_mc_remove - Unbind driver from controller.
> + * @pdev: Platform device.
> + *
> + * Return: 0
> + */
> +static int cdns_edac_mc_remove(struct platform_device *pdev)
> +{
> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
> + struct priv_data *priv = mci->pvt_info;
Could another CPU be running in edac_ecc_isr() when this is called....
> + /* Disable All ECC Interrupts for DDR4 Controller */
> + writel(ECC_CTL_INT_ENABLE_MASK, priv->reg + ECC_CTL_INT_MASK);
> +
> + /* Disable ecc feature before removing driver by writing 0 */
> + writel((unsigned int)(~(ECC_CTL_ECC_ENABLE)),
> + priv->reg + ECC_CTL_CONTROL_0_REG);
> +
> +#ifdef CONFIG_EDAC_DEBUG
> + remove_sysfs_attributes(mci);
> +#endif
> + edac_mc_del_mc(&pdev->dev);
> + edac_mc_free(mci);
... and now you've free()d the private data from underneath it.
I think you need an irqsave spinlock and a call to platform_set_drvdata(pdev, NULL).
edac_ecc_isr() would need to take the lock when using the private data, (nd return if its
NULL).
> + return 0;
> +}
Thanks,
James