misc: smpro-errmon: Add Ampere's SMpro error monitor driver

Add Ampere's SMpro error monitor driver for monitoring and reporting
RAS-related errors as reported by SMpro co-processor found on Ampere's
Altra processor family.

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
Link: https://lore.kernel.org/r/20221031024442.2490881-3-quan@os.amperecomputing.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 529 insertions, 0 deletions

diff --git a/drivers/misc/smpro-errmon.c b/drivers/misc/smpro-errmon.c
new file mode 100644
index 000000000000..d1431d419aa4
--- /dev/null
+++ b/drivers/misc/smpro-errmon.c
@@ -0,0 +1,529 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Ampere Computing SoC's SMpro Error Monitoring Driver
+ *
+ * Copyright (c) 2022, Ampere Computing LLC
+ *
+ */
+
+#include <linux/i2c.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* GPI RAS Error Registers */
+#define GPI_RAS_ERR		0x7E
+
+/* Core and L2C Error Registers */
+#define CORE_CE_ERR_CNT		0x80
+#define CORE_CE_ERR_LEN		0x81
+#define CORE_CE_ERR_DATA	0x82
+#define CORE_UE_ERR_CNT		0x83
+#define CORE_UE_ERR_LEN		0x84
+#define CORE_UE_ERR_DATA	0x85
+
+/* Memory Error Registers */
+#define MEM_CE_ERR_CNT		0x90
+#define MEM_CE_ERR_LEN		0x91
+#define MEM_CE_ERR_DATA		0x92
+#define MEM_UE_ERR_CNT		0x93
+#define MEM_UE_ERR_LEN		0x94
+#define MEM_UE_ERR_DATA		0x95
+
+/* RAS Error/Warning Registers */
+#define ERR_SMPRO_TYPE		0xA0
+#define ERR_PMPRO_TYPE		0xA1
+#define ERR_SMPRO_INFO_LO	0xA2
+#define ERR_SMPRO_INFO_HI	0xA3
+#define ERR_SMPRO_DATA_LO	0xA4
+#define ERR_SMPRO_DATA_HI	0xA5
+#define WARN_SMPRO_INFO_LO	0xAA
+#define WARN_SMPRO_INFO_HI	0xAB
+#define ERR_PMPRO_INFO_LO	0xA6
+#define ERR_PMPRO_INFO_HI	0xA7
+#define ERR_PMPRO_DATA_LO	0xA8
+#define ERR_PMPRO_DATA_HI	0xA9
+#define WARN_PMPRO_INFO_LO	0xAC
+#define WARN_PMPRO_INFO_HI	0xAD
+
+/* PCIE Error Registers */
+#define PCIE_CE_ERR_CNT		0xC0
+#define PCIE_CE_ERR_LEN		0xC1
+#define PCIE_CE_ERR_DATA	0xC2
+#define PCIE_UE_ERR_CNT		0xC3
+#define PCIE_UE_ERR_LEN		0xC4
+#define PCIE_UE_ERR_DATA	0xC5
+
+/* Other Error Registers */
+#define OTHER_CE_ERR_CNT	0xD0
+#define OTHER_CE_ERR_LEN	0xD1
+#define OTHER_CE_ERR_DATA	0xD2
+#define OTHER_UE_ERR_CNT	0xD8
+#define OTHER_UE_ERR_LEN	0xD9
+#define OTHER_UE_ERR_DATA	0xDA
+
+/* Event Data Registers */
+#define VRD_WARN_FAULT_EVENT_DATA	0x78
+#define VRD_HOT_EVENT_DATA		0x79
+#define DIMM_HOT_EVENT_DATA		0x7A
+
+#define MAX_READ_BLOCK_LENGTH	48
+
+#define RAS_SMPRO_ERR		0
+#define RAS_PMPRO_ERR		1
+
+enum RAS_48BYTES_ERR_TYPES {
+	CORE_CE_ERR,
+	CORE_UE_ERR,
+	MEM_CE_ERR,
+	MEM_UE_ERR,
+	PCIE_CE_ERR,
+	PCIE_UE_ERR,
+	OTHER_CE_ERR,
+	OTHER_UE_ERR,
+	NUM_48BYTES_ERR_TYPE,
+};
+
+struct smpro_error_hdr {
+	u8 count;	/* Number of the RAS errors */
+	u8 len;		/* Number of data bytes */
+	u8 data;	/* Start of 48-byte data */
+	u8 max_cnt;	/* Max num of errors */
+};
+
+/*
+ * Included Address of registers to get Count, Length of data and Data
+ * of the 48 bytes error data
+ */
+static struct smpro_error_hdr smpro_error_table[] = {
+	[CORE_CE_ERR] = {
+		.count = CORE_CE_ERR_CNT,
+		.len = CORE_CE_ERR_LEN,
+		.data = CORE_CE_ERR_DATA,
+		.max_cnt = 32
+	},
+	[CORE_UE_ERR] = {
+		.count = CORE_UE_ERR_CNT,
+		.len = CORE_UE_ERR_LEN,
+		.data = CORE_UE_ERR_DATA,
+		.max_cnt = 32
+	},
+	[MEM_CE_ERR] = {
+		.count = MEM_CE_ERR_CNT,
+		.len = MEM_CE_ERR_LEN,
+		.data = MEM_CE_ERR_DATA,
+		.max_cnt = 16
+	},
+	[MEM_UE_ERR] = {
+		.count = MEM_UE_ERR_CNT,
+		.len = MEM_UE_ERR_LEN,
+		.data = MEM_UE_ERR_DATA,
+		.max_cnt = 16
+	},
+	[PCIE_CE_ERR] = {
+		.count = PCIE_CE_ERR_CNT,
+		.len = PCIE_CE_ERR_LEN,
+		.data = PCIE_CE_ERR_DATA,
+		.max_cnt = 96
+	},
+	[PCIE_UE_ERR] = {
+		.count = PCIE_UE_ERR_CNT,
+		.len = PCIE_UE_ERR_LEN,
+		.data = PCIE_UE_ERR_DATA,
+		.max_cnt = 96
+	},
+	[OTHER_CE_ERR] = {
+		.count = OTHER_CE_ERR_CNT,
+		.len = OTHER_CE_ERR_LEN,
+		.data = OTHER_CE_ERR_DATA,
+		.max_cnt = 8
+	},
+	[OTHER_UE_ERR] = {
+		.count = OTHER_UE_ERR_CNT,
+		.len = OTHER_UE_ERR_LEN,
+		.data = OTHER_UE_ERR_DATA,
+		.max_cnt = 8
+	},
+};
+
+/*
+ * List of SCP registers which are used to get
+ * one type of RAS Internal errors.
+ */
+struct smpro_int_error_hdr {
+	u8 type;
+	u8 info_l;
+	u8 info_h;
+	u8 data_l;
+	u8 data_h;
+	u8 warn_l;
+	u8 warn_h;
+};
+
+static struct smpro_int_error_hdr list_smpro_int_error_hdr[] = {
+	[RAS_SMPRO_ERR] = {
+		.type = ERR_SMPRO_TYPE,
+		.info_l = ERR_SMPRO_INFO_LO,
+		.info_h = ERR_SMPRO_INFO_HI,
+		.data_l = ERR_SMPRO_DATA_LO,
+		.data_h = ERR_SMPRO_DATA_HI,
+		.warn_l = WARN_SMPRO_INFO_LO,
+		.warn_h = WARN_SMPRO_INFO_HI,
+	},
+	[RAS_PMPRO_ERR] = {
+		.type = ERR_PMPRO_TYPE,
+		.info_l = ERR_PMPRO_INFO_LO,
+		.info_h = ERR_PMPRO_INFO_HI,
+		.data_l = ERR_PMPRO_DATA_LO,
+		.data_h = ERR_PMPRO_DATA_HI,
+		.warn_l = WARN_PMPRO_INFO_LO,
+		.warn_h = WARN_PMPRO_INFO_HI,
+	},
+};
+
+struct smpro_errmon {
+	struct regmap *regmap;
+};
+
+enum EVENT_TYPES {
+	VRD_WARN_FAULT_EVENT,
+	VRD_HOT_EVENT,
+	DIMM_HOT_EVENT,
+	NUM_EVENTS_TYPE,
+};
+
+/* Included Address of event source and data registers */
+static u8 smpro_event_table[NUM_EVENTS_TYPE] = {
+	VRD_WARN_FAULT_EVENT_DATA,
+	VRD_HOT_EVENT_DATA,
+	DIMM_HOT_EVENT_DATA,
+};
+
+static ssize_t smpro_event_data_read(struct device *dev,
+				     struct device_attribute *da, char *buf,
+				     int channel)
+{
+	struct smpro_errmon *errmon = dev_get_drvdata(dev);
+	s32 event_data;
+	int ret;
+
+	ret = regmap_read(errmon->regmap, smpro_event_table[channel], &event_data);
+	if (ret)
+		return ret;
+	/* Clear event after read */
+	if (event_data != 0)
+		regmap_write(errmon->regmap, smpro_event_table[channel], event_data);
+
+	return sysfs_emit(buf, "%04x\n", event_data);
+}
+
+static ssize_t smpro_overflow_data_read(struct device *dev, struct device_attribute *da,
+					char *buf, int channel)
+{
+	struct smpro_errmon *errmon = dev_get_drvdata(dev);
+	struct smpro_error_hdr *err_info;
+	s32 err_count;
+	int ret;
+
+	err_info = &smpro_error_table[channel];
+
+	ret = regmap_read(errmon->regmap, err_info->count, &err_count);
+	if (ret)
+		return ret;
+
+	/* Bit 8 indicates the overflow status */
+	return sysfs_emit(buf, "%d\n", (err_count & BIT(8)) ? 1 : 0);
+}
+
+static ssize_t smpro_error_data_read(struct device *dev, struct device_attribute *da,
+				     char *buf, int channel)
+{
+	struct smpro_errmon *errmon = dev_get_drvdata(dev);
+	unsigned char err_data[MAX_READ_BLOCK_LENGTH];
+	struct smpro_error_hdr *err_info;
+	s32 err_count, err_length;
+	int ret;
+
+	err_info = &smpro_error_table[channel];
+
+	ret = regmap_read(errmon->regmap, err_info->count, &err_count);
+	/* Error count is the low byte */
+	err_count &= 0xff;
+	if (ret || !err_count || err_count > err_info->max_cnt)
+		return ret;
+
+	ret = regmap_read(errmon->regmap, err_info->len, &err_length);
+	if (ret || err_length <= 0)
+		return ret;
+
+	if (err_length > MAX_READ_BLOCK_LENGTH)
+		err_length = MAX_READ_BLOCK_LENGTH;
+
+	memset(err_data, 0x00, MAX_READ_BLOCK_LENGTH);
+	ret = regmap_noinc_read(errmon->regmap, err_info->data, err_data, err_length);
+	if (ret < 0)
+		return ret;
+
+	/* clear the error */
+	ret = regmap_write(errmon->regmap, err_info->count, 0x100);
+	if (ret)
+		return ret;
+	/*
+	 * The output of Core/Memory/PCIe/Others UE/CE errors follows the format
+	 * specified in section 5.8.1 CE/UE Error Data record in
+	 * Altra SOC BMC Interface specification.
+	 */
+	return sysfs_emit(buf, "%*phN\n", MAX_READ_BLOCK_LENGTH, err_data);
+}
+
+/*
+ * Output format:
+ * <4-byte hex value of error info><4-byte hex value of error extensive data>
+ * Where:
+ *   + error info : The error information
+ *   + error data : Extensive data (32 bits)
+ * Reference to section 5.10 RAS Internal Error Register Definition in
+ * Altra SOC BMC Interface specification
+ */
+static ssize_t smpro_internal_err_read(struct device *dev, struct device_attribute *da,
+				       char *buf, int channel)
+{
+	struct smpro_errmon *errmon = dev_get_drvdata(dev);
+	struct smpro_int_error_hdr *err_info;
+	unsigned int err[4] = { 0 };
+	unsigned int err_type;
+	unsigned int val;
+	int ret;
+
+	/* read error status */
+	ret = regmap_read(errmon->regmap, GPI_RAS_ERR, &val);
+	if (ret)
+		return ret;
+
+	if ((channel == RAS_SMPRO_ERR && !(val & BIT(0))) ||
+	    (channel == RAS_PMPRO_ERR && !(val & BIT(1))))
+		return 0;
+
+	err_info = &list_smpro_int_error_hdr[channel];
+	ret = regmap_read(errmon->regmap, err_info->type, &val);
+	if (ret)
+		return ret;
+
+	err_type = (val & BIT(1)) ? BIT(1) :
+		   (val & BIT(2)) ? BIT(2) : 0;
+
+	if (!err_type)
+		return 0;
+
+	ret = regmap_read(errmon->regmap, err_info->info_l, err + 1);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(errmon->regmap, err_info->info_h, err);
+	if (ret)
+		return ret;
+
+	if (err_type & BIT(2)) {
+		/* Error with data type */
+		ret = regmap_read(errmon->regmap, err_info->data_l, err + 3);
+		if (ret)
+			return ret;
+
+		ret = regmap_read(errmon->regmap, err_info->data_h, err + 2);
+		if (ret)
+			return ret;
+	}
+
+	/* clear the read errors */
+	ret = regmap_write(errmon->regmap, err_info->type, err_type);
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%*phN\n", (int)sizeof(err), err);
+}
+
+/*
+ * Output format:
+ * <4-byte hex value of warining info>
+ * Reference to section 5.10 RAS Internal Error Register Definition in
+ * Altra SOC BMC Interface specification
+ */
+static ssize_t smpro_internal_warn_read(struct device *dev, struct device_attribute *da,
+					char *buf, int channel)
+{
+	struct smpro_errmon *errmon = dev_get_drvdata(dev);
+	struct smpro_int_error_hdr *err_info;
+	unsigned int warn[2] = { 0 };
+	unsigned int val;
+	int ret;
+
+	/* read error status */
+	ret = regmap_read(errmon->regmap, GPI_RAS_ERR, &val);
+	if (ret)
+		return ret;
+
+	if ((channel == RAS_SMPRO_ERR && !(val & BIT(0))) ||
+	    (channel == RAS_PMPRO_ERR && !(val & BIT(1))))
+		return 0;
+
+	err_info = &list_smpro_int_error_hdr[channel];
+	ret = regmap_read(errmon->regmap, err_info->type, &val);
+	if (ret)
+		return ret;
+
+	if (!(val & BIT(0)))
+		return 0;
+
+	ret = regmap_read(errmon->regmap, err_info->warn_l, warn + 1);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(errmon->regmap, err_info->warn_h, warn);
+	if (ret)
+		return ret;
+
+	/* clear the warning */
+	ret = regmap_write(errmon->regmap, err_info->type, BIT(0));
+	if (ret)
+		return ret;
+
+	return sysfs_emit(buf, "%*phN\n", (int)sizeof(warn), warn);
+}
+
+#define ERROR_OVERFLOW_RO(_error, _index) \
+	static ssize_t overflow_##_error##_show(struct device *dev,            \
+						struct device_attribute *da,   \
+						char *buf)                     \
+	{                                                                      \
+		return smpro_overflow_data_read(dev, da, buf, _index);         \
+	}                                                                      \
+	static DEVICE_ATTR_RO(overflow_##_error)
+
+ERROR_OVERFLOW_RO(core_ce, CORE_CE_ERR);
+ERROR_OVERFLOW_RO(core_ue, CORE_UE_ERR);
+ERROR_OVERFLOW_RO(mem_ce, MEM_CE_ERR);
+ERROR_OVERFLOW_RO(mem_ue, MEM_UE_ERR);
+ERROR_OVERFLOW_RO(pcie_ce, PCIE_CE_ERR);
+ERROR_OVERFLOW_RO(pcie_ue, PCIE_UE_ERR);
+ERROR_OVERFLOW_RO(other_ce, OTHER_CE_ERR);
+ERROR_OVERFLOW_RO(other_ue, OTHER_UE_ERR);
+
+#define ERROR_RO(_error, _index) \
+	static ssize_t error_##_error##_show(struct device *dev,            \
+					     struct device_attribute *da,   \
+					     char *buf)                     \
+	{                                                                   \
+		return smpro_error_data_read(dev, da, buf, _index);         \
+	}                                                                   \
+	static DEVICE_ATTR_RO(error_##_error)
+
+ERROR_RO(core_ce, CORE_CE_ERR);
+ERROR_RO(core_ue, CORE_UE_ERR);
+ERROR_RO(mem_ce, MEM_CE_ERR);
+ERROR_RO(mem_ue, MEM_UE_ERR);
+ERROR_RO(pcie_ce, PCIE_CE_ERR);
+ERROR_RO(pcie_ue, PCIE_UE_ERR);
+ERROR_RO(other_ce, OTHER_CE_ERR);
+ERROR_RO(other_ue, OTHER_UE_ERR);
+
+static ssize_t error_smpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_err_read(dev, da, buf, RAS_SMPRO_ERR);
+}
+static DEVICE_ATTR_RO(error_smpro);
+
+static ssize_t error_pmpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_err_read(dev, da, buf, RAS_PMPRO_ERR);
+}
+static DEVICE_ATTR_RO(error_pmpro);
+
+static ssize_t warn_smpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_warn_read(dev, da, buf, RAS_SMPRO_ERR);
+}
+static DEVICE_ATTR_RO(warn_smpro);
+
+static ssize_t warn_pmpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_warn_read(dev, da, buf, RAS_PMPRO_ERR);
+}
+static DEVICE_ATTR_RO(warn_pmpro);
+
+#define EVENT_RO(_event, _index) \
+	static ssize_t event_##_event##_show(struct device *dev,            \
+					     struct device_attribute *da,   \
+					     char *buf)                     \
+	{                                                                   \
+		return smpro_event_data_read(dev, da, buf, _index);         \
+	}                                                                   \
+	static DEVICE_ATTR_RO(event_##_event)
+
+EVENT_RO(vrd_warn_fault, VRD_WARN_FAULT_EVENT);
+EVENT_RO(vrd_hot, VRD_HOT_EVENT);
+EVENT_RO(dimm_hot, DIMM_HOT_EVENT);
+
+static struct attribute *smpro_errmon_attrs[] = {
+	&dev_attr_overflow_core_ce.attr,
+	&dev_attr_overflow_core_ue.attr,
+	&dev_attr_overflow_mem_ce.attr,
+	&dev_attr_overflow_mem_ue.attr,
+	&dev_attr_overflow_pcie_ce.attr,
+	&dev_attr_overflow_pcie_ue.attr,
+	&dev_attr_overflow_other_ce.attr,
+	&dev_attr_overflow_other_ue.attr,
+	&dev_attr_error_core_ce.attr,
+	&dev_attr_error_core_ue.attr,
+	&dev_attr_error_mem_ce.attr,
+	&dev_attr_error_mem_ue.attr,
+	&dev_attr_error_pcie_ce.attr,
+	&dev_attr_error_pcie_ue.attr,
+	&dev_attr_error_other_ce.attr,
+	&dev_attr_error_other_ue.attr,
+	&dev_attr_error_smpro.attr,
+	&dev_attr_error_pmpro.attr,
+	&dev_attr_warn_smpro.attr,
+	&dev_attr_warn_pmpro.attr,
+	&dev_attr_event_vrd_warn_fault.attr,
+	&dev_attr_event_vrd_hot.attr,
+	&dev_attr_event_dimm_hot.attr,
+	NULL
+};
+
+ATTRIBUTE_GROUPS(smpro_errmon);
+
+static int smpro_errmon_probe(struct platform_device *pdev)
+{
+	struct smpro_errmon *errmon;
+
+	errmon = devm_kzalloc(&pdev->dev, sizeof(struct smpro_errmon), GFP_KERNEL);
+	if (!errmon)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, errmon);
+
+	errmon->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!errmon->regmap)
+		return -ENODEV;
+
+	return 0;
+}
+
+static struct platform_driver smpro_errmon_driver = {
+	.probe          = smpro_errmon_probe,
+	.driver = {
+		.name   = "smpro-errmon",
+		.dev_groups = smpro_errmon_groups,
+	},
+};
+
+module_platform_driver(smpro_errmon_driver);
+
+MODULE_AUTHOR("Tung Nguyen <tung.nguyen@amperecomputing.com>");
+MODULE_AUTHOR("Thinh Pham <thinh.pham@amperecomputing.com>");
+MODULE_AUTHOR("Hoang Nguyen <hnguyen@amperecomputing.com>");
+MODULE_AUTHOR("Thu Nguyen <thu@os.amperecomputing.com>");
+MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
+MODULE_DESCRIPTION("Ampere Altra SMpro driver");
+MODULE_LICENSE("GPL");