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From:   Quan Nguyen <quan@os.amperecomputing.com>
To:     Lee Jones <lee.jones@linaro.org>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzk+dt@kernel.org>,
        Jean Delvare <jdelvare@suse.com>,
        Guenter Roeck <linux@roeck-us.net>,
        Jonathan Corbet <corbet@lwn.net>,
        Derek Kiernan <derek.kiernan@xilinx.com>,
        Dragan Cvetic <dragan.cvetic@xilinx.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Quan Nguyen <quan@os.amperecomputing.com>,
        Thu Nguyen <thu@os.amperecomputing.com>,
        Gustavo Pimentel <Gustavo.Pimentel@synopsys.com>,
        linux-kernel@vger.kernel.org (open list),
        devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND FLATTENED
        DEVICE TREE BINDINGS),
        linux-hwmon@vger.kernel.org (open list:HARDWARE MONITORING),
        linux-doc@vger.kernel.org (open list:DOCUMENTATION),
        OpenBMC Maillist <openbmc@lists.ozlabs.org>
Cc:     Open Source Submission <patches@amperecomputing.com>,
        Phong Vo <phong@os.amperecomputing.com>,
        "Thang Q . Nguyen" <thang@os.amperecomputing.com>
Subject: [PATCH v7 3/9] misc: smpro-errmon: Add Ampere's SMpro error monitor driver
Date:   Mon, 21 Mar 2022 15:13:49 +0700
Message-Id: <20220321081355.6802-4-quan@os.amperecomputing.com>
In-Reply-To: <20220321081355.6802-1-quan@os.amperecomputing.com>
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This commit adds 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>
---
Changes in v7:
  + Remove regmap_acquire/release_lock(), read_i2c_block_data() [Quan]
  + Use regmap_noinc_read() instead of errmon_read_block()      [Quan]
  + Validate number of errors before read                       [Quan]
  + Fix wrong return type of *_show() function     [kernel test robot]
  + Adjust patch order to avoid dependence with smpro-mfd  [Lee Jones]
  + Use pointer instead of stack memory                         [Quan]

Changes in v6:
  + First introduced in v6 [Quan]

 drivers/misc/Kconfig        |   7 +
 drivers/misc/Makefile       |   1 +
 drivers/misc/smpro-errmon.c | 517 ++++++++++++++++++++++++++++++++++++
 3 files changed, 525 insertions(+)
 create mode 100644 drivers/misc/smpro-errmon.c

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index a2b26426efba..4e1a0b451f3d 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -176,6 +176,13 @@ config SGI_XP
 	  this feature will allow for direct communication between SSIs
 	  based on a network adapter and DMA messaging.
 
+config SMPRO_ERRMON
+	tristate "Ampere Computing SMPro error monitor driver"
+	depends on MFD_SMPRO || COMPILE_TEST
+	help
+	  If you say yes here you get support for error monitor function
+	  provides by Ampere Computing's SoC with SMpro processor.
+
 config CS5535_MFGPT
 	tristate "CS5535/CS5536 Geode Multi-Function General Purpose Timer (MFGPT) support"
 	depends on MFD_CS5535
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 70e800e9127f..483308a6e113 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_ENCLOSURE_SERVICES) += enclosure.o
 obj-$(CONFIG_KGDB_TESTS)	+= kgdbts.o
 obj-$(CONFIG_SGI_XP)		+= sgi-xp/
 obj-$(CONFIG_SGI_GRU)		+= sgi-gru/
+obj-$(CONFIG_SMPRO_ERRMON)	+= smpro-errmon.o
 obj-$(CONFIG_CS5535_MFGPT)	+= cs5535-mfgpt.o
 obj-$(CONFIG_GEHC_ACHC)		+= gehc-achc.o
 obj-$(CONFIG_HP_ILO)		+= hpilo.o
diff --git a/drivers/misc/smpro-errmon.c b/drivers/misc/smpro-errmon.c
new file mode 100644
index 000000000000..50970a48d5df
--- /dev/null
+++ b/drivers/misc/smpro-errmon.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * 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 DIMM_2X_REFRESH_EVENT_DATA	0x96
+
+#define MAX_READ_BLOCK_LENGTH	48
+#define NUM_I2C_MESSAGES	2
+#define MAX_MSG_LEN		128
+
+#define RAS_SMPRO_ERRS		0
+#define RAS_PMPRO_ERRS		1
+
+enum RAS_48BYTES_ERR_TYPES {
+	CORE_CE_ERRS,
+	CORE_UE_ERRS,
+	MEM_CE_ERRS,
+	MEM_UE_ERRS,
+	PCIE_CE_ERRS,
+	PCIE_UE_ERRS,
+	OTHER_CE_ERRS,
+	OTHER_UE_ERRS,
+	NUM_48BYTES_ERR_TYPE,
+};
+
+struct smpro_error_hdr {
+	u8 err_count;	/* Number of the RAS errors */
+	u8 err_len;	/* Number of data bytes */
+	u8 err_data;	/* Start of 48-byte data */
+	u8 max_err_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[NUM_48BYTES_ERR_TYPE] = {
+	{CORE_CE_ERR_CNT, CORE_CE_ERR_LEN, CORE_CE_ERR_DATA, 32},
+	{CORE_UE_ERR_CNT, CORE_UE_ERR_LEN, CORE_UE_ERR_DATA, 32},
+	{MEM_CE_ERR_CNT, MEM_CE_ERR_LEN, MEM_CE_ERR_DATA, 16},
+	{MEM_UE_ERR_CNT, MEM_UE_ERR_LEN, MEM_UE_ERR_DATA, 16},
+	{PCIE_CE_ERR_CNT, PCIE_CE_ERR_LEN, PCIE_CE_ERR_DATA, 96},
+	{PCIE_UE_ERR_CNT, PCIE_UE_ERR_LEN, PCIE_UE_ERR_DATA, 96},
+	{OTHER_CE_ERR_CNT, OTHER_CE_ERR_LEN, OTHER_CE_ERR_DATA, 8},
+	{OTHER_UE_ERR_CNT, OTHER_UE_ERR_LEN, OTHER_UE_ERR_DATA, 8},
+};
+
+/*
+ * List of SCP registers which are used to get
+ * one type of RAS Internal errors.
+ */
+struct smpro_int_error_hdr {
+	u8 err_type;
+	u8 err_info_low;
+	u8 err_info_high;
+	u8 err_data_high;
+	u8 err_data_low;
+	u8 warn_info_low;
+	u8 warn_info_high;
+};
+
+static struct smpro_int_error_hdr list_smpro_int_error_hdr[2] = {
+	{
+	 ERR_SMPRO_TYPE,
+	 ERR_SMPRO_INFO_LO, ERR_SMPRO_INFO_HI,
+	 ERR_SMPRO_DATA_LO, ERR_SMPRO_DATA_HI,
+	 WARN_SMPRO_INFO_LO, WARN_SMPRO_INFO_HI
+	},
+	{
+	 ERR_PMPRO_TYPE,
+	 ERR_PMPRO_INFO_LO, ERR_PMPRO_INFO_HI,
+	 ERR_PMPRO_DATA_LO, ERR_PMPRO_DATA_HI,
+	 WARN_PMPRO_INFO_LO, WARN_PMPRO_INFO_HI
+	},
+};
+
+struct smpro_errmon {
+	struct regmap *regmap;
+};
+
+enum EVENT_TYPES {
+	VRD_WARN_FAULT_EVENTS,
+	VRD_HOT_EVENTS,
+	DIMM_HOT_EVENTS,
+	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);
+	unsigned char msg[MAX_MSG_LEN] = {'\0'};
+	s32 event_data;
+	int ret;
+
+	*buf = 0;
+	if (channel >= NUM_EVENTS_TYPE)
+		goto done;
+
+	ret = regmap_read(errmon->regmap, smpro_event_table[channel], &event_data);
+	if (ret)
+		goto done;
+
+	ret = scnprintf(msg, MAX_MSG_LEN, "%02x %04x\n", channel, event_data);
+	strncat(buf, msg, ret);
+	/* Clear event after read */
+	if (event_data != 0)
+		regmap_write(errmon->regmap, smpro_event_table[channel], event_data);
+done:
+	return strlen(buf);
+}
+
+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];
+	unsigned char msg[MAX_MSG_LEN] = {'\0'};
+	struct smpro_error_hdr *err_info;
+	s32 err_count, err_length;
+	int ret, len, i;
+
+	*buf = 0;
+	if (channel >= NUM_48BYTES_ERR_TYPE)
+		goto done;
+
+	err_info = &smpro_error_table[channel];
+
+	ret = regmap_read(errmon->regmap, err_info->err_count, &err_count);
+	/* Error count is the low byte */
+	err_count &= 0xff;
+	if (ret || err_count > err_info->max_err_cnt)
+		goto done;
+
+	/* Bit 8 indentifies the overflow status of one error type */
+	if (err_count & BIT(8)) {
+		len = scnprintf(msg, MAX_MSG_LEN,
+				"%02x %02x %04x %08x %016llx %016llx %016llx %016llx %016llx\n",
+				0xFF, 0xFF, 0, 0, 0LL, 0LL, 0LL, 0LL, 0LL);
+		strncat(buf, msg, len);
+	}
+
+	for (i = 0; i < err_count; i++) {
+		ret = regmap_read(errmon->regmap, err_info->err_len, &err_length);
+		if (ret || err_length <= 0)
+			break;
+
+		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->err_data, err_data, err_length);
+		if (ret < 0)
+			break;
+
+		/*
+		 * The output of Core/Memory/PCIe/Others UE/CE errors follows below format:
+		 * <Error Type>  <Error SubType>  <Instance>  <Error Status> \
+		 * <Error Address>  <Error Misc 0> <Error Misc 1> <Error Misc2> <Error Misc 3>
+		 * Where:
+		 *  + Error Type: The hardwares cause the errors. (1 byte)
+		 *  + SubType: Sub type of error in the specified hardware error. (1 byte)
+		 *  + Instance: Combination of the socket, channel,
+		 *    slot cause the error. (2 bytes)
+		 *  + Error Status: Encode of error status. (4 bytes)
+		 *  + Error Address: The address in device causes the errors. (8 bytes)
+		 *  + Error Misc 0/1/2/3: Addition info about the errors. (8 bytes for each)
+		 * Reference Altra SOC BMC Interface specification.
+		 */
+		len = scnprintf(msg, MAX_MSG_LEN,
+				"%02x %02x %04x %08x %016llx %016llx %016llx %016llx %016llx\n",
+				err_data[0], err_data[1], *(u16 *)&err_data[2],
+				*(u32 *)&err_data[4], *(u64 *)&err_data[8],
+				*(u64 *)&err_data[16], *(u64 *)&err_data[24],
+				*(u64 *)&err_data[32], *(u64 *)&err_data[40]);
+
+		/* go to next error */
+		ret = regmap_write(errmon->regmap, err_info->err_count, 0x100);
+		if (ret)
+			break;
+
+		/* add error message to buffer */
+		strncat(buf, msg, len);
+	}
+done:
+	return strlen(buf);
+}
+
+static s32 smpro_internal_err_get_info(struct regmap *regmap, u8 addr, u8 addr1,
+				       u8 addr2, u8 addr3, u8 subtype, char *buf)
+{
+	unsigned int ret_hi, ret_lo, data_lo, data_hi;
+	int ret;
+
+	ret = regmap_read(regmap, addr, &ret_lo);
+	if (ret)
+		return ret;
+
+	ret = regmap_read(regmap, addr1, &ret_hi);
+	if (ret)
+		return ret;
+
+	if (addr2 != 0xff) {
+		ret = regmap_read(regmap, addr2, &data_lo);
+		if (ret)
+			return ret;
+		ret = regmap_read(regmap, addr3, &data_hi);
+		if (ret)
+			return ret;
+	}
+	/*
+	 * Output format:
+	 * <errType> <image> <dir> <Location> <errorCode> <data>
+	 * Where:
+	 *   + errType: SCP Error Type (3 bits)
+	 *      1: Warning
+	 *      2: Error
+	 *      4: Error with data
+	 *   + image: SCP Image Code (8 bits)
+	 *   + dir: Direction (1 bit)
+	 *      0: Enter
+	 *      1: Exit
+	 *   + location: SCP Module Location Code (8 bits)
+	 *   + errorCode: SCP Error Code (16 bits)
+	 *   + data : Extensive data (32 bits)
+	 *      All bits are 0 when errType is warning or error.
+	 */
+	return scnprintf(buf, MAX_MSG_LEN, "%01x %02x %01x %02x %04x %04x%04x\n",
+			 subtype, (ret_hi & 0xf000) >> 12, (ret_hi & 0x0800) >> 11,
+			 ret_hi & 0xff, ret_lo, data_hi, data_lo);
+}
+
+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 char msg[MAX_MSG_LEN] = {'\0'};
+	unsigned int err_type;
+	unsigned int value;
+	int ret = 0;
+
+	*buf = 0;
+	/* read error status */
+	ret = regmap_read(errmon->regmap, GPI_RAS_ERR, &value);
+	if (ret)
+		goto done;
+
+	if (!((channel == RAS_SMPRO_ERRS && (value & BIT(0))) ||
+	      (channel == RAS_PMPRO_ERRS && (value & BIT(1)))))
+		goto done;
+
+	err_info = &list_smpro_int_error_hdr[channel];
+	ret = regmap_read(errmon->regmap, err_info->err_type, &err_type);
+	if (ret)
+		goto done;
+
+	/* Warning type */
+	if (err_type & BIT(0)) {
+		ret = smpro_internal_err_get_info(errmon->regmap, err_info->warn_info_low,
+						  err_info->warn_info_high, 0xff, 0xff, 1, msg);
+		if (ret < 0)
+			goto done;
+
+		strncat(buf, msg, ret);
+	}
+
+	/* Error with data type */
+	if (err_type & BIT(2)) {
+		ret = smpro_internal_err_get_info(errmon->regmap,
+						  err_info->err_info_low,
+						  err_info->err_info_high,
+						  err_info->err_data_low,
+						  err_info->err_data_high, 4, msg);
+		if (ret < 0)
+			goto done;
+
+		strncat(buf, msg, ret);
+	}
+	/* Error type */
+	else if (err_type & BIT(1)) {
+		ret = smpro_internal_err_get_info(errmon->regmap,
+						  err_info->err_info_low,
+						  err_info->err_info_high,
+						  0xff, 0xff, 2, msg);
+		if (ret < 0)
+			goto done;
+
+		strncat(buf, msg, ret);
+	}
+
+	/* clear the read errors */
+	regmap_write(errmon->regmap, err_info->err_type, err_type);
+
+done:
+	return strlen(buf);
+}
+
+static ssize_t errors_core_ce_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, CORE_CE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_core_ce);
+
+static ssize_t errors_core_ue_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, CORE_UE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_core_ue);
+
+static ssize_t errors_mem_ce_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, MEM_CE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_mem_ce);
+
+static ssize_t errors_mem_ue_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, MEM_UE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_mem_ue);
+
+static ssize_t errors_pcie_ce_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, PCIE_CE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_pcie_ce);
+
+static ssize_t errors_pcie_ue_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, PCIE_UE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_pcie_ue);
+
+static ssize_t errors_other_ce_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, OTHER_CE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_other_ce);
+
+static ssize_t errors_other_ue_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_error_data_read(dev, da, buf, OTHER_UE_ERRS);
+}
+static DEVICE_ATTR_RO(errors_other_ue);
+
+static ssize_t errors_smpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_err_read(dev, da, buf, RAS_SMPRO_ERRS);
+}
+static DEVICE_ATTR_RO(errors_smpro);
+
+static ssize_t errors_pmpro_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_internal_err_read(dev, da, buf, RAS_PMPRO_ERRS);
+}
+static DEVICE_ATTR_RO(errors_pmpro);
+
+static ssize_t event_vrd_warn_fault_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_event_data_read(dev, da, buf, VRD_WARN_FAULT_EVENTS);
+}
+static DEVICE_ATTR_RO(event_vrd_warn_fault);
+
+static ssize_t event_vrd_hot_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_event_data_read(dev, da, buf, VRD_HOT_EVENTS);
+}
+static DEVICE_ATTR_RO(event_vrd_hot);
+
+static ssize_t event_dimm_hot_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	return smpro_event_data_read(dev, da, buf, DIMM_HOT_EVENTS);
+}
+static DEVICE_ATTR_RO(event_dimm_hot);
+
+static struct attribute *smpro_errmon_attrs[] = {
+	&dev_attr_errors_core_ce.attr,
+	&dev_attr_errors_core_ue.attr,
+	&dev_attr_errors_mem_ce.attr,
+	&dev_attr_errors_mem_ue.attr,
+	&dev_attr_errors_pcie_ce.attr,
+	&dev_attr_errors_pcie_ue.attr,
+	&dev_attr_errors_other_ce.attr,
+	&dev_attr_errors_other_ue.attr,
+	&dev_attr_errors_smpro.attr,
+	&dev_attr_errors_pmpro.attr,
+	&dev_attr_event_vrd_warn_fault.attr,
+	&dev_attr_event_vrd_hot.attr,
+	&dev_attr_event_dimm_hot.attr,
+	NULL
+};
+
+static const struct attribute_group smpro_errmon_attr_group = {
+	.attrs = smpro_errmon_attrs
+};
+
+static int smpro_errmon_probe(struct platform_device *pdev)
+{
+	struct smpro_errmon *errmon;
+	int ret;
+
+	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;
+
+	ret = sysfs_create_group(&pdev->dev.kobj, &smpro_errmon_attr_group);
+	if (ret)
+		dev_err(&pdev->dev, "SMPro errmon sysfs registration failed\n");
+
+	return 0;
+}
+
+static int smpro_errmon_remove(struct platform_device *pdev)
+{
+	sysfs_remove_group(&pdev->dev.kobj, &smpro_errmon_attr_group);
+	pr_info("SMPro errmon sysfs entries removed");
+
+	return 0;
+}
+
+static struct platform_driver smpro_errmon_driver = {
+	.probe          = smpro_errmon_probe,
+	.remove         = smpro_errmon_remove,
+	.driver = {
+		.name   = "smpro-errmon",
+	},
+};
+
+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");
-- 
2.35.1