1 files changed, 408 insertions, 0 deletions
diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c b/drivers/platform/x86/amd/hsmp/hsmp.c
new file mode 100644
index 000000000000..f29dd93fbf0b
--- /dev/null
+++ b/drivers/platform/x86/amd/hsmp/hsmp.c
@@ -0,0 +1,408 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD HSMP Platform Driver
+ * Copyright (c) 2022, AMD.
+ * All Rights Reserved.
+ *
+ * This file provides a device implementation for HSMP interface
+ */
+
+#include <asm/amd_hsmp.h>
+#include <asm/amd_nb.h>
+
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/semaphore.h>
+#include <linux/sysfs.h>
+
+#include "hsmp.h"
+
+/* HSMP Status / Error codes */
+#define HSMP_STATUS_NOT_READY	0x00
+#define HSMP_STATUS_OK		0x01
+#define HSMP_ERR_INVALID_MSG	0xFE
+#define HSMP_ERR_INVALID_INPUT	0xFF
+#define HSMP_ERR_PREREQ_NOT_SATISFIED	0xFD
+#define HSMP_ERR_SMU_BUSY		0xFC
+
+/* Timeout in millsec */
+#define HSMP_MSG_TIMEOUT	100
+#define HSMP_SHORT_SLEEP	1
+
+#define HSMP_WR			true
+#define HSMP_RD			false
+
+#define DRIVER_VERSION		"2.3"
+
+static struct hsmp_plat_device hsmp_pdev;
+
+/*
+ * Send a message to the HSMP port via PCI-e config space registers
+ * or by writing to MMIO space.
+ *
+ * The caller is expected to zero out any unused arguments.
+ * If a response is expected, the number of response words should be greater than 0.
+ *
+ * Returns 0 for success and populates the requested number of arguments.
+ * Returns a negative error code for failure.
+ */
+static int __hsmp_send_message(struct hsmp_socket *sock, struct hsmp_message *msg)
+{
+	struct hsmp_mbaddr_info *mbinfo;
+	unsigned long timeout, short_sleep;
+	u32 mbox_status;
+	u32 index;
+	int ret;
+
+	mbinfo = &sock->mbinfo;
+
+	/* Clear the status register */
+	mbox_status = HSMP_STATUS_NOT_READY;
+	ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_WR);
+	if (ret) {
+		dev_err(sock->dev, "Error %d clearing mailbox status register\n", ret);
+		return ret;
+	}
+
+	index = 0;
+	/* Write any message arguments */
+	while (index < msg->num_args) {
+		ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
+					  &msg->args[index], HSMP_WR);
+		if (ret) {
+			dev_err(sock->dev, "Error %d writing message argument %d\n", ret, index);
+			return ret;
+		}
+		index++;
+	}
+
+	/* Write the message ID which starts the operation */
+	ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_id_off, &msg->msg_id, HSMP_WR);
+	if (ret) {
+		dev_err(sock->dev, "Error %d writing message ID %u\n", ret, msg->msg_id);
+		return ret;
+	}
+
+	/*
+	 * Depending on when the trigger write completes relative to the SMU
+	 * firmware 1 ms cycle, the operation may take from tens of us to 1 ms
+	 * to complete. Some operations may take more. Therefore we will try
+	 * a few short duration sleeps and switch to long sleeps if we don't
+	 * succeed quickly.
+	 */
+	short_sleep = jiffies + msecs_to_jiffies(HSMP_SHORT_SLEEP);
+	timeout	= jiffies + msecs_to_jiffies(HSMP_MSG_TIMEOUT);
+
+	while (time_before(jiffies, timeout)) {
+		ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_resp_off, &mbox_status, HSMP_RD);
+		if (ret) {
+			dev_err(sock->dev, "Error %d reading mailbox status\n", ret);
+			return ret;
+		}
+
+		if (mbox_status != HSMP_STATUS_NOT_READY)
+			break;
+		if (time_before(jiffies, short_sleep))
+			usleep_range(50, 100);
+		else
+			usleep_range(1000, 2000);
+	}
+
+	if (unlikely(mbox_status == HSMP_STATUS_NOT_READY)) {
+		dev_err(sock->dev, "Message ID 0x%X failure : SMU tmeout (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -ETIMEDOUT;
+	} else if (unlikely(mbox_status == HSMP_ERR_INVALID_MSG)) {
+		dev_err(sock->dev, "Message ID 0x%X failure : Invalid message (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -ENOMSG;
+	} else if (unlikely(mbox_status == HSMP_ERR_INVALID_INPUT)) {
+		dev_err(sock->dev, "Message ID 0x%X failure : Invalid arguments (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -EINVAL;
+	} else if (unlikely(mbox_status == HSMP_ERR_PREREQ_NOT_SATISFIED)) {
+		dev_err(sock->dev, "Message ID 0x%X failure : Prerequisite not satisfied (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -EREMOTEIO;
+	} else if (unlikely(mbox_status == HSMP_ERR_SMU_BUSY)) {
+		dev_err(sock->dev, "Message ID 0x%X failure : SMU BUSY (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -EBUSY;
+	} else if (unlikely(mbox_status != HSMP_STATUS_OK)) {
+		dev_err(sock->dev, "Message ID 0x%X unknown failure (status = 0x%X)\n",
+			msg->msg_id, mbox_status);
+		return -EIO;
+	}
+
+	/*
+	 * SMU has responded OK. Read response data.
+	 * SMU reads the input arguments from eight 32 bit registers starting
+	 * from SMN_HSMP_MSG_DATA and writes the response data to the same
+	 * SMN_HSMP_MSG_DATA address.
+	 * We copy the response data if any, back to the args[].
+	 */
+	index = 0;
+	while (index < msg->response_sz) {
+		ret = sock->amd_hsmp_rdwr(sock, mbinfo->msg_arg_off + (index << 2),
+					  &msg->args[index], HSMP_RD);
+		if (ret) {
+			dev_err(sock->dev, "Error %d reading response %u for message ID:%u\n",
+				ret, index, msg->msg_id);
+			break;
+		}
+		index++;
+	}
+
+	return ret;
+}
+
+static int validate_message(struct hsmp_message *msg)
+{
+	/* msg_id against valid range of message IDs */
+	if (msg->msg_id < HSMP_TEST || msg->msg_id >= HSMP_MSG_ID_MAX)
+		return -ENOMSG;
+
+	/* msg_id is a reserved message ID */
+	if (hsmp_msg_desc_table[msg->msg_id].type == HSMP_RSVD)
+		return -ENOMSG;
+
+	/* num_args and response_sz against the HSMP spec */
+	if (msg->num_args != hsmp_msg_desc_table[msg->msg_id].num_args ||
+	    msg->response_sz != hsmp_msg_desc_table[msg->msg_id].response_sz)
+		return -EINVAL;
+
+	return 0;
+}
+
+int hsmp_send_message(struct hsmp_message *msg)
+{
+	struct hsmp_socket *sock;
+	int ret;
+
+	if (!msg)
+		return -EINVAL;
+	ret = validate_message(msg);
+	if (ret)
+		return ret;
+
+	if (!hsmp_pdev.sock || msg->sock_ind >= hsmp_pdev.num_sockets)
+		return -ENODEV;
+	sock = &hsmp_pdev.sock[msg->sock_ind];
+
+	/*
+	 * The time taken by smu operation to complete is between
+	 * 10us to 1ms. Sometime it may take more time.
+	 * In SMP system timeout of 100 millisecs should
+	 * be enough for the previous thread to finish the operation
+	 */
+	ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));
+	if (ret < 0)
+		return ret;
+
+	ret = __hsmp_send_message(sock, msg);
+
+	up(&sock->hsmp_sem);
+
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_send_message, AMD_HSMP);
+
+int hsmp_test(u16 sock_ind, u32 value)
+{
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	/*
+	 * Test the hsmp port by performing TEST command. The test message
+	 * takes one argument and returns the value of that argument + 1.
+	 */
+	msg.msg_id	= HSMP_TEST;
+	msg.num_args	= 1;
+	msg.response_sz	= 1;
+	msg.args[0]	= value;
+	msg.sock_ind	= sock_ind;
+
+	ret = hsmp_send_message(&msg);
+	if (ret)
+		return ret;
+
+	/* Check the response value */
+	if (msg.args[0] != (value + 1)) {
+		dev_err(hsmp_pdev.sock[sock_ind].dev,
+			"Socket %d test message failed, Expected 0x%08X, received 0x%08X\n",
+			sock_ind, (value + 1), msg.args[0]);
+		return -EBADE;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_test, AMD_HSMP);
+
+long hsmp_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
+{
+	int __user *arguser = (int  __user *)arg;
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	if (copy_struct_from_user(&msg, sizeof(msg), arguser, sizeof(struct hsmp_message)))
+		return -EFAULT;
+
+	/*
+	 * Check msg_id is within the range of supported msg ids
+	 * i.e within the array bounds of hsmp_msg_desc_table
+	 */
+	if (msg.msg_id < HSMP_TEST || msg.msg_id >= HSMP_MSG_ID_MAX)
+		return -ENOMSG;
+
+	switch (fp->f_mode & (FMODE_WRITE | FMODE_READ)) {
+	case FMODE_WRITE:
+		/*
+		 * Device is opened in O_WRONLY mode
+		 * Execute only set/configure commands
+		 */
+		if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_SET)
+			return -EPERM;
+		break;
+	case FMODE_READ:
+		/*
+		 * Device is opened in O_RDONLY mode
+		 * Execute only get/monitor commands
+		 */
+		if (hsmp_msg_desc_table[msg.msg_id].type != HSMP_GET)
+			return -EPERM;
+		break;
+	case FMODE_READ | FMODE_WRITE:
+		/*
+		 * Device is opened in O_RDWR mode
+		 * Execute both get/monitor and set/configure commands
+		 */
+		break;
+	default:
+		return -EPERM;
+	}
+
+	ret = hsmp_send_message(&msg);
+	if (ret)
+		return ret;
+
+	if (hsmp_msg_desc_table[msg.msg_id].response_sz > 0) {
+		/* Copy results back to user for get/monitor commands */
+		if (copy_to_user(arguser, &msg, sizeof(struct hsmp_message)))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size)
+{
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	if (!sock || !buf)
+		return -EINVAL;
+
+	/* Do not support lseek(), also don't allow more than the size of metric table */
+	if (size != sizeof(struct hsmp_metric_table)) {
+		dev_err(sock->dev, "Wrong buffer size\n");
+		return -EINVAL;
+	}
+
+	msg.msg_id	= HSMP_GET_METRIC_TABLE;
+	msg.sock_ind	= sock->sock_ind;
+
+	ret = hsmp_send_message(&msg);
+	if (ret)
+		return ret;
+	memcpy_fromio(buf, sock->metric_tbl_addr, size);
+
+	return size;
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_metric_tbl_read, AMD_HSMP);
+
+int hsmp_get_tbl_dram_base(u16 sock_ind)
+{
+	struct hsmp_socket *sock = &hsmp_pdev.sock[sock_ind];
+	struct hsmp_message msg = { 0 };
+	phys_addr_t dram_addr;
+	int ret;
+
+	msg.sock_ind	= sock_ind;
+	msg.response_sz	= hsmp_msg_desc_table[HSMP_GET_METRIC_TABLE_DRAM_ADDR].response_sz;
+	msg.msg_id	= HSMP_GET_METRIC_TABLE_DRAM_ADDR;
+
+	ret = hsmp_send_message(&msg);
+	if (ret)
+		return ret;
+
+	/*
+	 * calculate the metric table DRAM address from lower and upper 32 bits
+	 * sent from SMU and ioremap it to virtual address.
+	 */
+	dram_addr = msg.args[0] | ((u64)(msg.args[1]) << 32);
+	if (!dram_addr) {
+		dev_err(sock->dev, "Invalid DRAM address for metric table\n");
+		return -ENOMEM;
+	}
+	sock->metric_tbl_addr = devm_ioremap(sock->dev, dram_addr,
+					     sizeof(struct hsmp_metric_table));
+	if (!sock->metric_tbl_addr) {
+		dev_err(sock->dev, "Failed to ioremap metric table addr\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_get_tbl_dram_base, AMD_HSMP);
+
+int hsmp_cache_proto_ver(u16 sock_ind)
+{
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	msg.msg_id	= HSMP_GET_PROTO_VER;
+	msg.sock_ind	= sock_ind;
+	msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz;
+
+	ret = hsmp_send_message(&msg);
+	if (!ret)
+		hsmp_pdev.proto_ver = msg.args[0];
+
+	return ret;
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_cache_proto_ver, AMD_HSMP);
+
+static const struct file_operations hsmp_fops = {
+	.owner		= THIS_MODULE,
+	.unlocked_ioctl	= hsmp_ioctl,
+	.compat_ioctl	= hsmp_ioctl,
+};
+
+int hsmp_misc_register(struct device *dev)
+{
+	hsmp_pdev.mdev.name	= HSMP_CDEV_NAME;
+	hsmp_pdev.mdev.minor	= MISC_DYNAMIC_MINOR;
+	hsmp_pdev.mdev.fops	= &hsmp_fops;
+	hsmp_pdev.mdev.parent	= dev;
+	hsmp_pdev.mdev.nodename	= HSMP_DEVNODE_NAME;
+	hsmp_pdev.mdev.mode	= 0644;
+
+	return misc_register(&hsmp_pdev.mdev);
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_misc_register, AMD_HSMP);
+
+void hsmp_misc_deregister(void)
+{
+	misc_deregister(&hsmp_pdev.mdev);
+}
+EXPORT_SYMBOL_NS_GPL(hsmp_misc_deregister, AMD_HSMP);
+
+struct hsmp_plat_device *get_hsmp_pdev(void)
+{
+	return &hsmp_pdev;
+}
+EXPORT_SYMBOL_NS_GPL(get_hsmp_pdev, AMD_HSMP);
+
+MODULE_DESCRIPTION("AMD HSMP Common driver");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");