Add driver for memory controller present on Nuvoton NPCM SoCs. The
memory controller supports single bit error correction and double bit
error detection.
Signed-off-by: Marvin Lin <[email protected]>
---
MAINTAINERS | 8 +
drivers/edac/Kconfig | 11 +
drivers/edac/Makefile | 1 +
drivers/edac/npcm_edac.c | 520 +++++++++++++++++++++++++++++++++++++++
4 files changed, 540 insertions(+)
create mode 100644 drivers/edac/npcm_edac.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 5a4526a171d6..0ac91ceaa829 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7524,6 +7524,14 @@ L: [email protected]
S: Maintained
F: drivers/edac/mpc85xx_edac.[ch]
+EDAC-NPCM
+M: Marvin Lin <[email protected]>
+M: Stanley Chu <[email protected]>
+L: [email protected]
+S: Maintained
+F: Documentation/devicetree/bindings/memory-controllers/nuvoton,npcm-memory-controller.yaml
+F: drivers/edac/npcm_edac.c
+
EDAC-PASEMI
M: Egor Martovetsky <[email protected]>
L: [email protected]
diff --git a/drivers/edac/Kconfig b/drivers/edac/Kconfig
index 4cfdefbd744d..aa575f5b3125 100644
--- a/drivers/edac/Kconfig
+++ b/drivers/edac/Kconfig
@@ -542,4 +542,15 @@ config EDAC_DMC520
Support for error detection and correction on the
SoCs with ARM DMC-520 DRAM controller.
+config EDAC_NPCM
+ tristate "Nuvoton NPCM DDR Memory Controller"
+ depends on (ARCH_NPCM || COMPILE_TEST)
+ help
+ Support for error detection and correction on the Nuvoton NPCM DDR
+ memory controller.
+
+ The memory controller supports single bit error correction, double bit
+ error detection (in-line ECC in which a section 1/8th of the memory
+ device used to store data is used for ECC storage).
+
endif # EDAC
diff --git a/drivers/edac/Makefile b/drivers/edac/Makefile
index 2d1641a27a28..db3c59d3ad84 100644
--- a/drivers/edac/Makefile
+++ b/drivers/edac/Makefile
@@ -84,3 +84,4 @@ 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_NPCM) += npcm_edac.o
diff --git a/drivers/edac/npcm_edac.c b/drivers/edac/npcm_edac.c
new file mode 100644
index 000000000000..875abff7a048
--- /dev/null
+++ b/drivers/edac/npcm_edac.c
@@ -0,0 +1,520 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2022 Nuvoton Technology Corporation
+
+#include <linux/debugfs.h>
+#include <linux/iopoll.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include "edac_module.h"
+
+#define EDAC_MOD_NAME "npcm-edac"
+#define EDAC_MSG_SIZE 256
+
+/* chip serials */
+#define NPCM7XX_CHIP BIT(0)
+#define NPCM8XX_CHIP BIT(1)
+
+/* syndrome values */
+#define UE_SYNDROME 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 struct regmap *npcm_regmap;
+
+struct npcm_platform_data {
+ /* chip serials */
+ int chip;
+
+ /* memory controller registers */
+ u32 ctl_ecc_en;
+ u32 ctl_int_status;
+ u32 ctl_int_ack;
+ u32 ctl_int_mask_master;
+ u32 ctl_int_mask_ecc;
+ u32 ctl_ce_addr_l;
+ u32 ctl_ce_addr_h;
+ u32 ctl_ce_data_l;
+ u32 ctl_ce_data_h;
+ u32 ctl_ce_synd;
+ u32 ctl_ue_addr_l;
+ u32 ctl_ue_addr_h;
+ u32 ctl_ue_data_l;
+ u32 ctl_ue_data_h;
+ u32 ctl_ue_synd;
+ u32 ctl_source_id;
+ u32 ctl_controller_busy;
+ u32 ctl_xor_check_bits;
+
+ /* masks and shifts */
+ u32 ecc_en_mask;
+ u32 int_status_ce_mask;
+ u32 int_status_ue_mask;
+ u32 int_ack_ce_mask;
+ u32 int_ack_ue_mask;
+ u32 int_mask_master_non_ecc_mask;
+ u32 int_mask_master_global_mask;
+ u32 int_mask_ecc_non_event_mask;
+ u32 ce_addr_h_mask;
+ u32 ce_synd_mask;
+ u32 ce_synd_shift;
+ u32 ue_addr_h_mask;
+ u32 ue_synd_mask;
+ u32 ue_synd_shift;
+ u32 source_id_ce_mask;
+ u32 source_id_ce_shift;
+ u32 source_id_ue_mask;
+ u32 source_id_ue_shift;
+ u32 controller_busy_mask;
+ u32 xor_check_bits_mask;
+ u32 xor_check_bits_shift;
+ u32 writeback_en_mask;
+ u32 fwc_mask;
+};
+
+struct priv_data {
+ void __iomem *reg;
+ char message[EDAC_MSG_SIZE];
+ const struct npcm_platform_data *pdata;
+
+ /* error injection */
+ struct dentry *debugfs;
+ u8 error_type;
+ u8 location;
+ u8 bit;
+};
+
+static void handle_ce(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+ u64 addr = 0;
+ u64 data = 0;
+ u32 val_h = 0;
+ u32 val_l, id, synd;
+
+ regmap_read(npcm_regmap, pdata->ctl_ce_addr_l, &val_l);
+ if (pdata->chip == NPCM8XX_CHIP) {
+ regmap_read(npcm_regmap, pdata->ctl_ce_addr_h, &val_h);
+ val_h &= pdata->ce_addr_h_mask;
+ }
+ addr = ((addr | val_h) << 32) | val_l;
+
+ regmap_read(npcm_regmap, pdata->ctl_ce_data_l, &val_l);
+ if (pdata->chip == NPCM8XX_CHIP)
+ regmap_read(npcm_regmap, pdata->ctl_ce_data_h, &val_h);
+ data = ((data | val_h) << 32) | val_l;
+
+ regmap_read(npcm_regmap, pdata->ctl_source_id, &id);
+ id = (id & pdata->source_id_ce_mask) >> pdata->source_id_ce_shift;
+
+ regmap_read(npcm_regmap, pdata->ctl_ce_synd, &synd);
+ synd = (synd & pdata->ce_synd_mask) >> pdata->ce_synd_shift;
+
+ snprintf(priv->message, EDAC_MSG_SIZE,
+ "addr = 0x%llx, data = 0x%llx, id = 0x%x", addr, data, id);
+
+ edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1, addr >> PAGE_SHIFT,
+ addr & ~PAGE_MASK, synd, 0, 0, -1, priv->message,
+ "");
+}
+
+static void handle_ue(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+ u64 addr = 0;
+ u64 data = 0;
+ u32 val_h = 0;
+ u32 val_l, id, synd;
+
+ regmap_read(npcm_regmap, pdata->ctl_ue_addr_l, &val_l);
+ if (pdata->chip == NPCM8XX_CHIP) {
+ regmap_read(npcm_regmap, pdata->ctl_ue_addr_h, &val_h);
+ val_h &= pdata->ue_addr_h_mask;
+ }
+ addr = ((addr | val_h) << 32) | val_l;
+
+ regmap_read(npcm_regmap, pdata->ctl_ue_data_l, &val_l);
+ if (pdata->chip == NPCM8XX_CHIP)
+ regmap_read(npcm_regmap, pdata->ctl_ue_data_h, &val_h);
+ data = ((data | val_h) << 32) | val_l;
+
+ regmap_read(npcm_regmap, pdata->ctl_source_id, &id);
+ id = (id & pdata->source_id_ue_mask) >> pdata->source_id_ue_shift;
+
+ regmap_read(npcm_regmap, pdata->ctl_ue_synd, &synd);
+ synd = (synd & pdata->ue_synd_mask) >> pdata->ue_synd_shift;
+
+ snprintf(priv->message, EDAC_MSG_SIZE,
+ "addr = 0x%llx, data = 0x%llx, id = 0x%x", addr, data, id);
+
+ edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
+ addr >> PAGE_SHIFT, addr & ~PAGE_MASK, synd, 0, 0,
+ -1, priv->message, "");
+}
+
+static irqreturn_t edac_ecc_isr(int irq, void *dev_id)
+{
+ struct mem_ctl_info *mci = dev_id;
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+ u32 status;
+
+ regmap_read(npcm_regmap, pdata->ctl_int_status, &status);
+ if (status & pdata->int_status_ce_mask) {
+ handle_ce(mci);
+
+ /* acknowledge the CE interrupt */
+ regmap_write(npcm_regmap, pdata->ctl_int_ack,
+ pdata->int_ack_ce_mask);
+ return IRQ_HANDLED;
+ } else if (status & pdata->int_status_ue_mask) {
+ handle_ue(mci);
+
+ /* acknowledge the UE interrupt */
+ regmap_write(npcm_regmap, pdata->ctl_int_ack,
+ pdata->int_ack_ue_mask);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static ssize_t force_ecc_error(struct file *file, const char __user *data,
+ size_t count, loff_t *ppos)
+{
+ struct device *dev = file->private_data;
+ struct mem_ctl_info *mci = to_mci(dev);
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+ int ret;
+ u32 val, syndrome;
+
+ /*
+ * error_type - 0: CE, 1: UE
+ * location - 0: data, 1: checkcode
+ * bit - 0 ~ 63 for data and 0 ~ 7 for checkcode
+ */
+ edac_printk(KERN_INFO, EDAC_MOD_NAME,
+ "force an ECC error, type = %d, location = %d, bit = %d\n",
+ priv->error_type, priv->location, priv->bit);
+
+ /* ensure no pending writes */
+ ret = regmap_read_poll_timeout(npcm_regmap, pdata->ctl_controller_busy,
+ val, !(val & pdata->controller_busy_mask),
+ 1000, 10000);
+ if (ret) {
+ edac_printk(KERN_INFO, EDAC_MOD_NAME,
+ "wait pending writes timeout\n");
+ return count;
+ }
+
+ regmap_read(npcm_regmap, pdata->ctl_xor_check_bits, &val);
+ val &= ~pdata->xor_check_bits_mask;
+
+ /* write syndrome to XOR_CHECK_BITS */
+ if (priv->error_type == 0) {
+ if (priv->location == 0 && priv->bit > 63) {
+ edac_printk(KERN_INFO, EDAC_MOD_NAME,
+ "data bit should not exceed 63\n");
+ return count;
+ }
+
+ if (priv->location == 1 && priv->bit > 7) {
+ edac_printk(KERN_INFO, EDAC_MOD_NAME,
+ "checkcode bit should not exceed 7\n");
+ return count;
+ }
+
+ syndrome = priv->location ? 1 << priv->bit :
+ data_synd[priv->bit];
+
+ regmap_write(npcm_regmap, pdata->ctl_xor_check_bits,
+ val | (syndrome << pdata->xor_check_bits_shift) |
+ pdata->writeback_en_mask);
+ } else if (priv->error_type == 1) {
+ regmap_write(npcm_regmap, pdata->ctl_xor_check_bits,
+ val | (UE_SYNDROME << pdata->xor_check_bits_shift));
+ }
+
+ /* force write check */
+ regmap_update_bits(npcm_regmap, pdata->ctl_xor_check_bits,
+ pdata->fwc_mask, pdata->fwc_mask);
+
+ return count;
+}
+
+static const struct file_operations force_ecc_error_fops = {
+ .open = simple_open,
+ .write = force_ecc_error,
+ .llseek = generic_file_llseek,
+};
+
+static void setup_debugfs(struct mem_ctl_info *mci)
+{
+ struct priv_data *priv = mci->pvt_info;
+
+ priv->debugfs = edac_debugfs_create_dir(mci->mod_name);
+ if (!priv->debugfs)
+ return;
+
+ edac_debugfs_create_x8("error_type", 0644, priv->debugfs,
+ &priv->error_type);
+ edac_debugfs_create_x8("location", 0644, priv->debugfs,
+ &priv->location);
+ edac_debugfs_create_x8("bit", 0644, priv->debugfs, &priv->bit);
+ edac_debugfs_create_file("force_ecc_error", 0200, priv->debugfs,
+ &mci->dev, &force_ecc_error_fops);
+}
+
+static int setup_irq(struct mem_ctl_info *mci, struct platform_device *pdev)
+{
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+ int ret, irq;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ edac_printk(KERN_ERR, EDAC_MOD_NAME, "IRQ not defined in DTS\n");
+ return irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, irq, edac_ecc_isr, 0,
+ dev_name(&pdev->dev), mci);
+ if (ret < 0) {
+ edac_printk(KERN_ERR, EDAC_MOD_NAME, "failed to request IRQ\n");
+ return ret;
+ }
+
+ /* enable the functional group of ECC and mask the others */
+ regmap_write(npcm_regmap, pdata->ctl_int_mask_master,
+ pdata->int_mask_master_non_ecc_mask);
+
+ if (pdata->chip == NPCM8XX_CHIP)
+ regmap_write(npcm_regmap, pdata->ctl_int_mask_ecc,
+ pdata->int_mask_ecc_non_event_mask);
+
+ return 0;
+}
+
+static const struct regmap_config npcm_regmap_cfg = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+};
+
+static int edac_probe(struct platform_device *pdev)
+{
+ const struct npcm_platform_data *pdata;
+ struct device *dev = &pdev->dev;
+ struct edac_mc_layer layers[1];
+ struct mem_ctl_info *mci;
+ struct priv_data *priv;
+ void __iomem *reg;
+ int rc;
+ u32 val;
+
+ reg = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(reg))
+ return PTR_ERR(reg);
+
+ npcm_regmap = devm_regmap_init_mmio(dev, reg, &npcm_regmap_cfg);
+ if (IS_ERR(npcm_regmap))
+ return PTR_ERR(npcm_regmap);
+
+ pdata = of_device_get_match_data(dev);
+ if (!pdata)
+ return -EINVAL;
+
+ /* bail out if ECC is not enabled */
+ regmap_read(npcm_regmap, pdata->ctl_ecc_en, &val);
+ if (!(val & pdata->ecc_en_mask)) {
+ edac_printk(KERN_ERR, EDAC_MOD_NAME, "ECC is not enabled\n");
+ return -EPERM;
+ }
+
+ edac_op_state = EDAC_OPSTATE_INT;
+
+ layers[0].type = EDAC_MC_LAYER_ALL_MEM;
+ layers[0].size = 1;
+
+ mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
+ sizeof(struct priv_data));
+ if (!mci)
+ return -ENOMEM;
+
+ mci->pdev = &pdev->dev;
+ priv = mci->pvt_info;
+ priv->reg = reg;
+ priv->pdata = pdata;
+ platform_set_drvdata(pdev, mci);
+
+ mci->mtype_cap = MEM_FLAG_DDR4;
+ mci->edac_ctl_cap = EDAC_FLAG_SECDED;
+ mci->scrub_cap = SCRUB_FLAG_HW_SRC;
+ mci->scrub_mode = SCRUB_HW_SRC;
+ mci->edac_cap = EDAC_FLAG_SECDED;
+ mci->ctl_name = "npcm_ddr_controller";
+ mci->dev_name = dev_name(&pdev->dev);
+ mci->mod_name = EDAC_MOD_NAME;
+ mci->ctl_page_to_phys = NULL;
+
+ rc = setup_irq(mci, pdev);
+ if (rc)
+ goto free_edac_mc;
+
+ rc = edac_mc_add_mc(mci);
+ if (rc)
+ goto free_edac_mc;
+
+ if (IS_ENABLED(CONFIG_EDAC_DEBUG) && pdata->chip == NPCM8XX_CHIP)
+ setup_debugfs(mci);
+
+ return rc;
+
+free_edac_mc:
+ edac_mc_free(mci);
+ return rc;
+}
+
+static int edac_remove(struct platform_device *pdev)
+{
+ struct mem_ctl_info *mci = platform_get_drvdata(pdev);
+ struct priv_data *priv = mci->pvt_info;
+ const struct npcm_platform_data *pdata = priv->pdata;
+
+ regmap_write(npcm_regmap, pdata->ctl_int_mask_master,
+ pdata->int_mask_master_global_mask);
+ regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask,
+ 0);
+
+ edac_mc_del_mc(&pdev->dev);
+ edac_mc_free(mci);
+
+ if (IS_ENABLED(CONFIG_EDAC_DEBUG) && pdata->chip == NPCM8XX_CHIP)
+ edac_debugfs_remove_recursive(priv->debugfs);
+
+ return 0;
+}
+
+static const struct npcm_platform_data npcm750_edac = {
+ .chip = NPCM7XX_CHIP,
+
+ /* memory controller registers */
+ .ctl_ecc_en = 0x174,
+ .ctl_int_status = 0x1d0,
+ .ctl_int_ack = 0x1d4,
+ .ctl_int_mask_master = 0x1d8,
+ .ctl_ce_addr_l = 0x188,
+ .ctl_ce_data_l = 0x190,
+ .ctl_ce_synd = 0x18c,
+ .ctl_ue_addr_l = 0x17c,
+ .ctl_ue_data_l = 0x184,
+ .ctl_ue_synd = 0x180,
+ .ctl_source_id = 0x194,
+
+ /* masks and shifts */
+ .ecc_en_mask = BIT(24),
+ .int_status_ce_mask = GENMASK(4, 3),
+ .int_status_ue_mask = GENMASK(6, 5),
+ .int_ack_ce_mask = GENMASK(4, 3),
+ .int_ack_ue_mask = GENMASK(6, 5),
+ .int_mask_master_non_ecc_mask = GENMASK(30, 7) | GENMASK(2, 0),
+ .int_mask_master_global_mask = BIT(31),
+ .ce_synd_mask = GENMASK(6, 0),
+ .ce_synd_shift = 0,
+ .ue_synd_mask = GENMASK(6, 0),
+ .ue_synd_shift = 0,
+ .source_id_ce_mask = GENMASK(29, 16),
+ .source_id_ce_shift = 16,
+ .source_id_ue_mask = GENMASK(13, 0),
+ .source_id_ue_shift = 0,
+};
+
+static const struct npcm_platform_data npcm845_edac = {
+ .chip = NPCM8XX_CHIP,
+
+ /* memory controller registers */
+ .ctl_ecc_en = 0x16c,
+ .ctl_int_status = 0x228,
+ .ctl_int_ack = 0x244,
+ .ctl_int_mask_master = 0x220,
+ .ctl_int_mask_ecc = 0x260,
+ .ctl_ce_addr_l = 0x18c,
+ .ctl_ce_addr_h = 0x190,
+ .ctl_ce_data_l = 0x194,
+ .ctl_ce_data_h = 0x198,
+ .ctl_ce_synd = 0x190,
+ .ctl_ue_addr_l = 0x17c,
+ .ctl_ue_addr_h = 0x180,
+ .ctl_ue_data_l = 0x184,
+ .ctl_ue_data_h = 0x188,
+ .ctl_ue_synd = 0x180,
+ .ctl_source_id = 0x19c,
+ .ctl_controller_busy = 0x20c,
+ .ctl_xor_check_bits = 0x174,
+
+ /* masks and shifts */
+ .ecc_en_mask = GENMASK(17, 16),
+ .int_status_ce_mask = GENMASK(1, 0),
+ .int_status_ue_mask = GENMASK(3, 2),
+ .int_ack_ce_mask = GENMASK(1, 0),
+ .int_ack_ue_mask = GENMASK(3, 2),
+ .int_mask_master_non_ecc_mask = GENMASK(30, 3) | GENMASK(1, 0),
+ .int_mask_master_global_mask = BIT(31),
+ .int_mask_ecc_non_event_mask = GENMASK(8, 4),
+ .ce_addr_h_mask = GENMASK(1, 0),
+ .ce_synd_mask = GENMASK(15, 8),
+ .ce_synd_shift = 8,
+ .ue_addr_h_mask = GENMASK(1, 0),
+ .ue_synd_mask = GENMASK(15, 8),
+ .ue_synd_shift = 8,
+ .source_id_ce_mask = GENMASK(29, 16),
+ .source_id_ce_shift = 16,
+ .source_id_ue_mask = GENMASK(13, 0),
+ .source_id_ue_shift = 0,
+ .controller_busy_mask = BIT(0),
+ .xor_check_bits_mask = GENMASK(23, 16),
+ .xor_check_bits_shift = 16,
+ .writeback_en_mask = BIT(24),
+ .fwc_mask = BIT(8),
+};
+
+static const struct of_device_id npcm_edac_of_match[] = {
+ {
+ .compatible = "nuvoton,npcm750-memory-controller",
+ .data = &npcm750_edac
+ },
+ {
+ .compatible = "nuvoton,npcm845-memory-controller",
+ .data = &npcm845_edac
+ },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, npcm_edac_of_match);
+
+static struct platform_driver npcm_edac_driver = {
+ .driver = {
+ .name = "npcm-edac",
+ .of_match_table = npcm_edac_of_match,
+ },
+ .probe = edac_probe,
+ .remove = edac_remove,
+};
+
+module_platform_driver(npcm_edac_driver);
+
+MODULE_AUTHOR("Medad CChien <[email protected]>");
+MODULE_AUTHOR("Marvin Lin <[email protected]>");
+MODULE_DESCRIPTION("Nuvoton NPCM EDAC Driver");
+MODULE_LICENSE("GPL");
--
2.34.1
On Fri, Dec 23, 2022 at 11:28:59AM +0800, Marvin Lin wrote:
> +static void handle_ce(struct mem_ctl_info *mci)
> +{
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> + u64 addr = 0;
> + u64 data = 0;
> + u32 val_h = 0;
> + u32 val_l, id, synd;
u32 val_h = 0, val_l, id, synd;
u64 addr = 0, data = 0;
Also, for all your functions:
The EDAC tree preferred ordering of variable declarations at the
beginning of a function is reverse fir tree order::
struct long_struct_name *descriptive_name;
unsigned long foo, bar;
unsigned int tmp;
int ret;
The above is faster to parse than the reverse ordering::
int ret;
unsigned int tmp;
unsigned long foo, bar;
struct long_struct_name *descriptive_name;
And even more so than random ordering::
unsigned long foo, bar;
int ret;
struct long_struct_name *descriptive_name;
unsigned int tmp;
> + regmap_read(npcm_regmap, pdata->ctl_ce_addr_l, &val_l);
> + if (pdata->chip == NPCM8XX_CHIP) {
> + regmap_read(npcm_regmap, pdata->ctl_ce_addr_h, &val_h);
> + val_h &= pdata->ce_addr_h_mask;
> + }
> + addr = ((addr | val_h) << 32) | val_l;
> +
> + regmap_read(npcm_regmap, pdata->ctl_ce_data_l, &val_l);
> + if (pdata->chip == NPCM8XX_CHIP)
> + regmap_read(npcm_regmap, pdata->ctl_ce_data_h, &val_h);
> + data = ((data | val_h) << 32) | val_l;
> +
> + regmap_read(npcm_regmap, pdata->ctl_source_id, &id);
> + id = (id & pdata->source_id_ce_mask) >> pdata->source_id_ce_shift;
> +
> + regmap_read(npcm_regmap, pdata->ctl_ce_synd, &synd);
> + synd = (synd & pdata->ce_synd_mask) >> pdata->ce_synd_shift;
> +
> + snprintf(priv->message, EDAC_MSG_SIZE,
> + "addr = 0x%llx, data = 0x%llx, id = 0x%x", addr, data, id);
> +
> + edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1, addr >> PAGE_SHIFT,
> + addr & ~PAGE_MASK, synd, 0, 0, -1, priv->message,
No need for that linebreak with the trailing piece.
> + "");
> +}
> +
> +static void handle_ue(struct mem_ctl_info *mci)
> +{
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> + u64 addr = 0;
> + u64 data = 0;
> + u32 val_h = 0;
> + u32 val_l, id, synd;
As above.
> +
> + regmap_read(npcm_regmap, pdata->ctl_ue_addr_l, &val_l);
> + if (pdata->chip == NPCM8XX_CHIP) {
> + regmap_read(npcm_regmap, pdata->ctl_ue_addr_h, &val_h);
> + val_h &= pdata->ue_addr_h_mask;
> + }
> + addr = ((addr | val_h) << 32) | val_l;
> +
> + regmap_read(npcm_regmap, pdata->ctl_ue_data_l, &val_l);
> + if (pdata->chip == NPCM8XX_CHIP)
> + regmap_read(npcm_regmap, pdata->ctl_ue_data_h, &val_h);
> + data = ((data | val_h) << 32) | val_l;
> +
> + regmap_read(npcm_regmap, pdata->ctl_source_id, &id);
> + id = (id & pdata->source_id_ue_mask) >> pdata->source_id_ue_shift;
> +
> + regmap_read(npcm_regmap, pdata->ctl_ue_synd, &synd);
> + synd = (synd & pdata->ue_synd_mask) >> pdata->ue_synd_shift;
> +
> + snprintf(priv->message, EDAC_MSG_SIZE,
> + "addr = 0x%llx, data = 0x%llx, id = 0x%x", addr, data, id);
> +
> + edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 1,
> + addr >> PAGE_SHIFT, addr & ~PAGE_MASK, synd, 0, 0,
> + -1, priv->message, "");
> +}
> +
> +static irqreturn_t edac_ecc_isr(int irq, void *dev_id)
> +{
> + struct mem_ctl_info *mci = dev_id;
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> + u32 status;
> +
> + regmap_read(npcm_regmap, pdata->ctl_int_status, &status);
> + if (status & pdata->int_status_ce_mask) {
> + handle_ce(mci);
> +
> + /* acknowledge the CE interrupt */
> + regmap_write(npcm_regmap, pdata->ctl_int_ack,
> + pdata->int_ack_ce_mask);
> + return IRQ_HANDLED;
> + } else if (status & pdata->int_status_ue_mask) {
> + handle_ue(mci);
> +
> + /* acknowledge the UE interrupt */
> + regmap_write(npcm_regmap, pdata->ctl_int_ack,
> + pdata->int_ack_ue_mask);
> + return IRQ_HANDLED;
> + }
WARN_ON_ONCE(1);
to catch weird cases.
> +
> + return IRQ_NONE;
> +}
> +
> +static ssize_t force_ecc_error(struct file *file, const char __user *data,
> + size_t count, loff_t *ppos)
> +{
> + struct device *dev = file->private_data;
> + struct mem_ctl_info *mci = to_mci(dev);
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> + int ret;
> + u32 val, syndrome;
> +
> + /*
> + * error_type - 0: CE, 1: UE
> + * location - 0: data, 1: checkcode
> + * bit - 0 ~ 63 for data and 0 ~ 7 for checkcode
> + */
> + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> + "force an ECC error, type = %d, location = %d, bit = %d\n",
> + priv->error_type, priv->location, priv->bit);
> +
> + /* ensure no pending writes */
> + ret = regmap_read_poll_timeout(npcm_regmap, pdata->ctl_controller_busy,
> + val, !(val & pdata->controller_busy_mask),
> + 1000, 10000);
> + if (ret) {
> + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> + "wait pending writes timeout\n");
> + return count;
> + }
> +
> + regmap_read(npcm_regmap, pdata->ctl_xor_check_bits, &val);
> + val &= ~pdata->xor_check_bits_mask;
> +
> + /* write syndrome to XOR_CHECK_BITS */
> + if (priv->error_type == 0) {
if (priv->error_type == ERROR_TYPE_CORRECTABLE
Use defines. Below too.
> + if (priv->location == 0 && priv->bit > 63) {
> + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> + "data bit should not exceed 63\n");
"data bit should not exceed 63 (%d)\n", priv->bit...)
Below too.
> + return count;
> + }
> +
> + if (priv->location == 1 && priv->bit > 7) {
> + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> + "checkcode bit should not exceed 7\n");
> + return count;
> + }
> +
> + syndrome = priv->location ? 1 << priv->bit :
> + data_synd[priv->bit];
syndrome = priv->location ? 1 << priv->bit
: data_synd[priv->bit];
> + regmap_write(npcm_regmap, pdata->ctl_xor_check_bits,
> + val | (syndrome << pdata->xor_check_bits_shift) |
> + pdata->writeback_en_mask);
> + } else if (priv->error_type == 1) {
> + regmap_write(npcm_regmap, pdata->ctl_xor_check_bits,
> + val | (UE_SYNDROME << pdata->xor_check_bits_shift));
> + }
> +
> + /* force write check */
> + regmap_update_bits(npcm_regmap, pdata->ctl_xor_check_bits,
> + pdata->fwc_mask, pdata->fwc_mask);
> +
> + return count;
> +}
> +
> +static const struct file_operations force_ecc_error_fops = {
> + .open = simple_open,
> + .write = force_ecc_error,
> + .llseek = generic_file_llseek,
> +};
> +
I'd find it helpful if there were a short recipe in a comment here
explaining how the injection should be done...
> +static void setup_debugfs(struct mem_ctl_info *mci)
> +{
> + struct priv_data *priv = mci->pvt_info;
> +
> + priv->debugfs = edac_debugfs_create_dir(mci->mod_name);
> + if (!priv->debugfs)
> + return;
> +
> + edac_debugfs_create_x8("error_type", 0644, priv->debugfs,
> + &priv->error_type);
> + edac_debugfs_create_x8("location", 0644, priv->debugfs,
> + &priv->location);
> + edac_debugfs_create_x8("bit", 0644, priv->debugfs, &priv->bit);
> + edac_debugfs_create_file("force_ecc_error", 0200, priv->debugfs,
> + &mci->dev, &force_ecc_error_fops);
> +}
> +
> +static int setup_irq(struct mem_ctl_info *mci, struct platform_device *pdev)
> +{
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> + int ret, irq;
> +
> + irq = platform_get_irq(pdev, 0);
> + if (irq < 0) {
> + edac_printk(KERN_ERR, EDAC_MOD_NAME, "IRQ not defined in DTS\n");
> + return irq;
> + }
> +
> + ret = devm_request_irq(&pdev->dev, irq, edac_ecc_isr, 0,
> + dev_name(&pdev->dev), mci);
> + if (ret < 0) {
> + edac_printk(KERN_ERR, EDAC_MOD_NAME, "failed to request IRQ\n");
> + return ret;
> + }
> +
> + /* enable the functional group of ECC and mask the others */
> + regmap_write(npcm_regmap, pdata->ctl_int_mask_master,
> + pdata->int_mask_master_non_ecc_mask);
> +
> + if (pdata->chip == NPCM8XX_CHIP)
> + regmap_write(npcm_regmap, pdata->ctl_int_mask_ecc,
> + pdata->int_mask_ecc_non_event_mask);
> +
> + return 0;
> +}
> +
> +static const struct regmap_config npcm_regmap_cfg = {
> + .reg_bits = 32,
> + .reg_stride = 4,
> + .val_bits = 32,
> +};
> +
> +static int edac_probe(struct platform_device *pdev)
> +{
> + const struct npcm_platform_data *pdata;
> + struct device *dev = &pdev->dev;
> + struct edac_mc_layer layers[1];
> + struct mem_ctl_info *mci;
> + struct priv_data *priv;
> + void __iomem *reg;
> + int rc;
> + u32 val;
> +
> + reg = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(reg))
> + return PTR_ERR(reg);
> +
> + npcm_regmap = devm_regmap_init_mmio(dev, reg, &npcm_regmap_cfg);
> + if (IS_ERR(npcm_regmap))
> + return PTR_ERR(npcm_regmap);
> +
> + pdata = of_device_get_match_data(dev);
> + if (!pdata)
> + return -EINVAL;
> +
> + /* bail out if ECC is not enabled */
> + regmap_read(npcm_regmap, pdata->ctl_ecc_en, &val);
> + if (!(val & pdata->ecc_en_mask)) {
> + edac_printk(KERN_ERR, EDAC_MOD_NAME, "ECC is not enabled\n");
> + return -EPERM;
> + }
> +
> + edac_op_state = EDAC_OPSTATE_INT;
> +
> + layers[0].type = EDAC_MC_LAYER_ALL_MEM;
> + layers[0].size = 1;
> +
> + mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
> + sizeof(struct priv_data));
> + if (!mci)
> + return -ENOMEM;
> +
> + mci->pdev = &pdev->dev;
> + priv = mci->pvt_info;
> + priv->reg = reg;
> + priv->pdata = pdata;
> + platform_set_drvdata(pdev, mci);
> +
> + mci->mtype_cap = MEM_FLAG_DDR4;
> + mci->edac_ctl_cap = EDAC_FLAG_SECDED;
> + mci->scrub_cap = SCRUB_FLAG_HW_SRC;
> + mci->scrub_mode = SCRUB_HW_SRC;
> + mci->edac_cap = EDAC_FLAG_SECDED;
> + mci->ctl_name = "npcm_ddr_controller";
> + mci->dev_name = dev_name(&pdev->dev);
> + mci->mod_name = EDAC_MOD_NAME;
> + mci->ctl_page_to_phys = NULL;
> +
> + rc = setup_irq(mci, pdev);
> + if (rc)
> + goto free_edac_mc;
> +
> + rc = edac_mc_add_mc(mci);
> + if (rc)
> + goto free_edac_mc;
> +
> + if (IS_ENABLED(CONFIG_EDAC_DEBUG) && pdata->chip == NPCM8XX_CHIP)
> + setup_debugfs(mci);
> +
> + return rc;
> +
> +free_edac_mc:
> + edac_mc_free(mci);
> + return rc;
> +}
> +
> +static int edac_remove(struct platform_device *pdev)
> +{
> + struct mem_ctl_info *mci = platform_get_drvdata(pdev);
> + struct priv_data *priv = mci->pvt_info;
> + const struct npcm_platform_data *pdata = priv->pdata;
> +
> + regmap_write(npcm_regmap, pdata->ctl_int_mask_master,
> + pdata->int_mask_master_global_mask);
> + regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask,
> + 0);
You have a bunch of those things: the 80 cols rule is not a rigid and a
static one - you should rather apply common sense. As in:
Does it make sense to have this ugly linebreak with only the 0 argument there?
regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask,
0);
or should I simply let it stick out:
regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask, 0);
and have much more readable code?
Please apply common sense to all your linebreaks above.
> +
> + edac_mc_del_mc(&pdev->dev);
> + edac_mc_free(mci);
<--- What happens if someone tries to inject errors right at this
moment, when you've freed the mci?
Hint: you should destroy resources in the opposite order you've
allocated them.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
Hi Boris,
Thanks for the review.
> > + u64 addr = 0;
> > + u64 data = 0;
> > + u32 val_h = 0;
> > + u32 val_l, id, synd;
>
> u32 val_h = 0, val_l, id, synd;
> u64 addr = 0, data = 0;
>
> Also, for all your functions:
>
> The EDAC tree preferred ordering of variable declarations at the
> beginning of a function is reverse fir tree order::
>
> struct long_struct_name *descriptive_name;
> unsigned long foo, bar;
> unsigned int tmp;
> int ret;
>
> The above is faster to parse than the reverse ordering::
>
> int ret;
> unsigned int tmp;
> unsigned long foo, bar;
> struct long_struct_name *descriptive_name;
>
> And even more so than random ordering::
>
> unsigned long foo, bar;
> int ret;
> struct long_struct_name *descriptive_name;
> unsigned int tmp;
I'll check all functions and follow this order.
> > + edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, 1, addr >> PAGE_SHIFT,
> > + addr & ~PAGE_MASK, synd, 0, 0, -1, priv->message,
>
> No need for that linebreak with the trailing piece.
>
> > + "");
> > + u64 addr = 0;
> > + u64 data = 0;
> > + u32 val_h = 0;
> > + u32 val_l, id, synd;
>
> As above.
Check.
> > + regmap_read(npcm_regmap, pdata->ctl_int_status, &status);
> > + if (status & pdata->int_status_ce_mask) {
> > + handle_ce(mci);
> > +
> > + /* acknowledge the CE interrupt */
> > + regmap_write(npcm_regmap, pdata->ctl_int_ack,
> > + pdata->int_ack_ce_mask);
> > + return IRQ_HANDLED;
> > + } else if (status & pdata->int_status_ue_mask) {
> > + handle_ue(mci);
> > +
> > + /* acknowledge the UE interrupt */
> > + regmap_write(npcm_regmap, pdata->ctl_int_ack,
> > + pdata->int_ack_ue_mask);
> > + return IRQ_HANDLED;
> > + }
>
> WARN_ON_ONCE(1);
>
> to catch weird cases.
OK.
> > + /* write syndrome to XOR_CHECK_BITS */
> > + if (priv->error_type == 0) {
>
> if (priv->error_type == ERROR_TYPE_CORRECTABLE
>
> Use defines. Below too.
>
> > + if (priv->location == 0 && priv->bit > 63) {
Will add defines.
> > + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> > + "data bit should not exceed 63\n");
>
> "data bit should not exceed 63 (%d)\n", priv->bit...)
>
> Below too.
>
> > + return count;
> > + }
> > +
> > + if (priv->location == 1 && priv->bit > 7) {
> > + edac_printk(KERN_INFO, EDAC_MOD_NAME,
> > + "checkcode bit should not exceed 7\n");
OK.
> > + syndrome = priv->location ? 1 << priv->bit :
> > + data_synd[priv->bit];
>
> syndrome = priv->location ? 1 << priv->bit
> : data_synd[priv->bit];
Just to confirm the indentation, is it right as follows?
syndrome = priv->location ? 1 << priv->bit
: data_synd[priv->bit];
And I was wondering if I should just remove the line break and let it stick out?
> I'd find it helpful if there were a short recipe in a comment here
> explaining how the injection should be done...
>
> > +static void setup_debugfs(struct mem_ctl_info *mci)
> > +{
OK, will add some injection examples here.
> > + regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask,
> > + 0);
>
> You have a bunch of those things: the 80 cols rule is not a rigid and a
> static one - you should rather apply common sense. As in:
>
> Does it make sense to have this ugly linebreak with only the 0 argument there?
>
> regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask,
> 0);
>
> or should I simply let it stick out:
>
> regmap_update_bits(npcm_regmap, pdata->ctl_ecc_en, pdata->ecc_en_mask, 0);
>
> and have much more readable code?
>
> Please apply common sense to all your linebreaks above.
Thanks for the guide.
> > + edac_mc_del_mc(&pdev->dev);
> > + edac_mc_free(mci);
>
> <--- What happens if someone tries to inject errors right at this
> moment, when you've freed the mci?
>
> Hint: you should destroy resources in the opposite order you've
> allocated them.
Understand. I'll correct the destroy order.
Regards,
Marvin
On Mon, Dec 26, 2022 at 11:50:54AM +0800, Kun-Fa Lin wrote:
> > > + syndrome = priv->location ? 1 << priv->bit :
> > > + data_synd[priv->bit];
> >
> > syndrome = priv->location ? 1 << priv->bit
> > : data_synd[priv->bit];
>
> Just to confirm the indentation, is it right as follows?
>
> syndrome = priv->location ? 1 << priv->bit
> : data_synd[priv->bit];
>
> And I was wondering if I should just remove the line break and let it stick out?
The idea is to have the '?' and the ':' under each other so that one
can visually immediately "parse" where each of the sides of the ternary
statement start.
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette