On Fri, Feb 28, 2020 at 10:43:21AM +0100, 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. > > Signed-off-by: Dhananjay Kangude <dkangude@xxxxxxxxxxx> > --- > drivers/edac/Kconfig | 7 + > drivers/edac/Makefile | 1 + > drivers/edac/cadence_edac.c | 615 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 623 insertions(+) > create mode 100644 drivers/edac/cadence_edac.c > > diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig > index fe2eb892a1bd..4bea37900e5d 100644 > --- a/drivers/edac/Kconfig > +++ b/drivers/edac/Kconfig > @@ -530,4 +530,11 @@ 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" I'm guessing this is ARM hardware? If so, it needs to have the proper ARCH dependency - see this file - drivers/edac/Kconfig - for examples. > + help > + Support for error detection and correction on the Cadence DDR > + memory controller. The driver provide the statistics for single bit(CE) I think you wanna say something like: "The driver reports correctable and uncorrectable memory errors." > + and double bit(UE) error correction. > + > endif # EDAC > diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile > index 269e15118cea..a56cf2ec6043 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 000000000000..0a96de7708b0 > --- /dev/null > +++ b/drivers/edac/cadence_edac.c > @@ -0,0 +1,615 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Cadence DDR4-ECC EDAC Driver. > + * > + * * Copyright (C) 2018-2019 Cadence Design Systems. > + * > + * * Authors: Dhananjay Kangude <dkangude@xxxxxxxxxxx>, > + */ > +#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" Align that one vertically too. > +#define FORCED_ECC_ERR_EVENT_SUPPORT 1 What's that for? > +/* Number of cs_rows needed per memory controller */ > +#define CDNS_EDAC_NR_CSROWS 2 Unused. Remove pls. Audit your whole driver for unused defines like that and drop them. > + > +/* Number of channels per memory controller */ > +#define CDNS_EDAC_NR_CHANS 1 That one too. > + > +/* 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 */ Add a space between the '*' and the first letter. Check all comments. > +#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. > + * @quirks: To differentiate IP features. This reads strange: you have a struct member called "quirks" which is used to differentiate features? Why not call it u64 ip_features; and turn it into a proper bitfield with proper member names which would make the code a lot more readable: if (p->forced_ecc_event_support) ... Or if (p->ip_features & FEAT_FORCED_ECC_ERR_EVENT) ? p->quirks testing for features looks strange. > + */ > +struct cdns_platform_data { > + int quirks; > +}; > + > +/** > + * struct cdns_edac_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 cdns_edac_priv_data { This is only used in this driver so you can just as well call it simply "priv_data" - no need for prefixes and the like. > + 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 cdns_edac_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); Check return value. > + > + 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; Carve the loop body out into a separate function called something like __init_dimm() or so for improved readability. > + } > + } > +} > + > +/** > + * 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 cdns_edac_priv_data *priv; > + u32 intr_status; > + u32 val; > + u32 sig_val_l, sig_val_h; > + u32 err_c_id, err_u_id; > + u32 err_c_synd, err_u_synd; > + u64 err_c_addr = 0x0, err_u_addr = 0x0; > + u64 err_c_data = 0x0, err_u_data = 0x0; Please sort function local variables declaration in a reverse christmas tree order: <type A> longest_variable_name; <type B> shorter_var_name; <type C> even_shorter; <type D> i; > + > + 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) { > + 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, ""); > + > + /* 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"); That could be a separate function: handle_ec() > + } > + > + if (val & ECC_UE_INTR_MASK) { > + 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, ""); > + > + /* 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"); That could be a separate function: handle_ue() > + } > + > + 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 cdns_edac_priv_data *priv = mci->pvt_info; > + int args_cnt; > + int ret; > + char **args; > + char buf[1000]; Srsly? 1kB on the stack? > + u32 regval; > + u8 user_word; > + u8 bit_no; > + > + /* Read sysfs params into buffer*/ > + snprintf(buf, min_t(size_t, sizeof(buf) - 1, count), "%s\n", data); > + /*Split string buffer into separate parameters*/ > + args = argv_split(GFP_KERNEL, buf, &args_cnt); Why can't you split data directly? > + > + 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) { Save an indentation level: if (!readl(priv->reg + ECC_CTL_CONTROL_0_REG) & ECC_CTL_ECC_ENABLE) return count; /* Check ... */ > + /* 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); > + } This whole thing needs a serious massaging because it is highly unreadable. Let those long lines stick out, think about using helper functions, etc. > + return count; > +} > + > +static DEVICE_ATTR_RW(forced_ecc_error); > +static int edac_create_sysfs_attributes(struct mem_ctl_info *mci) Drop the "edac_" prefix from driver-local functions. Audit the whole driver pls. > +{ > + int rc; > + > + rc = device_create_file(&mci->dev, &dev_attr_forced_ecc_error); > + if (rc < 0) > + return rc; > + return 0; > +} > + > +static void edac_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 > + .quirks = FORCED_ECC_ERR_EVENT_SUPPORT, > +#endif > +}; > + > +static const struct of_device_id cdns_edac_of_match[] = { > + { .compatible = "cdns,cadence-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. > + */ > + <---- newline here. > +static int cdns_edac_mc_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct resource *res; > + void __iomem *reg; > + struct mem_ctl_info *mci; > + struct edac_mc_layer layers[1]; > + const struct of_device_id *id; > + struct cdns_edac_priv_data *priv_data; > + int irq, ret = -ENODEV; > +#ifdef CONFIG_EDAC_DEBUG > + const struct cdns_platform_data *p; > +#endif Please sort function local variables declaration in a reverse christmas tree order: <type A> longest_variable_name; <type B> shorter_var_name; <type C> even_shorter; <type D> i; > + 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); Unchecked retval. > + 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 cdns_edac_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"); s/ecc/ECC/g For the whole driver. > + 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->quirks && FORCED_ECC_ERR_EVENT_SUPPORT) { > + if (edac_create_sysfs_attributes(mci)) { > + edac_printk(KERN_ERR, CDNS_EDAC_MOD_NAME, > + "Failed to create sysfs entries\n"); > + goto err; After you've done edac_mc_add_mc(), you need to do edac_mc_del_mc(). Look at how the other drivers do it and test your driver with CONFIG_KASAN and CONFIG_DEBUG_TEST_DRIVER_REMOVE. Thx. -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette