diff --git a/Documentation/userspace-api/ioctl/ioctl-number.rst b/Documentation/userspace-api/ioctl/ioctl-number.rst
index 687efcf245c13d34196044e2500354224f0fa538..663e316d320c052edc93bdee8eea4a7d8e82559d 100644
--- a/Documentation/userspace-api/ioctl/ioctl-number.rst
+++ b/Documentation/userspace-api/ioctl/ioctl-number.rst
@@ -372,6 +372,8 @@ Code Seq# Include File Comments
<mailto:thomas@winischhofer.net>
0xF6 all LTTng Linux Trace Toolkit Next Generation
<mailto:mathieu.desnoyers@efficios.com>
+0xF8 all arch/x86/include/uapi/asm/amd_hsmp.h AMD HSMP EPYC system management interface driver
+ <mailto:nchatrad@amd.com>
0xFD all linux/dm-ioctl.h
0xFE all linux/isst_if.h
==== ===== ======================================================= ================================================================
diff --git a/MAINTAINERS b/MAINTAINERS
index 136f817428cf0179c8283a6252fd8df6a6b3c4c4..a419a6938786a2bc04402e33bcfc3686f37776a0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -988,6 +988,16 @@ L: platform-driver-x86@vger.kernel.org
S: Maintained
F: drivers/platform/x86/amd-pmc.*
+AMD HSMP DRIVER
+M: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
+R: Carlos Bilbao <carlos.bilbao@amd.com>
+L: platform-driver-x86@vger.kernel.org
+S: Maintained
+F: Documentation/x86/amd_hsmp.rst
+F: arch/x86/include/asm/amd_hsmp.h
+F: arch/x86/include/uapi/asm/amd_hsmp.h
+F: drivers/platform/x86/amd_hsmp.c
+
AMD POWERPLAY AND SWSMU
M: Evan Quan <evan.quan@amd.com>
L: amd-gfx@lists.freedesktop.org
diff --git a/arch/x86/include/asm/amd_hsmp.h b/arch/x86/include/asm/amd_hsmp.h
new file mode 100644
index 0000000000000000000000000000000000000000..03c2ce3edaf5a5a1b6b2ee74f38f0a039ade7bb1
--- /dev/null
+++ b/arch/x86/include/asm/amd_hsmp.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+
+#ifndef _ASM_X86_AMD_HSMP_H_
+#define _ASM_X86_AMD_HSMP_H_
+
+#include <uapi/asm/amd_hsmp.h>
+
+#if IS_ENABLED(CONFIG_AMD_HSMP)
+int hsmp_send_message(struct hsmp_message *msg);
+#else
+static inline int hsmp_send_message(struct hsmp_message *msg)
+{
+ return -ENODEV;
+}
+#endif
+#endif /*_ASM_X86_AMD_HSMP_H_*/
diff --git a/arch/x86/include/uapi/asm/amd_hsmp.h b/arch/x86/include/uapi/asm/amd_hsmp.h
new file mode 100644
index 0000000000000000000000000000000000000000..7ee7ba0d63a352c1c22a36b82bcbc0510cfc9570
--- /dev/null
+++ b/arch/x86/include/uapi/asm/amd_hsmp.h
@@ -0,0 +1,203 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+
+#ifndef _UAPI_ASM_X86_AMD_HSMP_H_
+#define _UAPI_ASM_X86_AMD_HSMP_H_
+
+#include <linux/types.h>
+
+#pragma pack(4)
+
+#define HSMP_MAX_MSG_LEN 8
+
+/*
+ * HSMP Messages supported
+ */
+enum hsmp_message_ids {
+ HSMP_TEST = 1, /* 01h Increments input value by 1 */
+ HSMP_GET_SMU_VER, /* 02h SMU FW version */
+ HSMP_GET_PROTO_VER, /* 03h HSMP interface version */
+ HSMP_GET_SOCKET_POWER, /* 04h average package power consumption */
+ HSMP_SET_SOCKET_POWER_LIMIT, /* 05h Set the socket power limit */
+ HSMP_GET_SOCKET_POWER_LIMIT, /* 06h Get current socket power limit */
+ HSMP_GET_SOCKET_POWER_LIMIT_MAX,/* 07h Get maximum socket power value */
+ HSMP_SET_BOOST_LIMIT, /* 08h Set a core maximum frequency limit */
+ HSMP_SET_BOOST_LIMIT_SOCKET, /* 09h Set socket maximum frequency level */
+ HSMP_GET_BOOST_LIMIT, /* 0Ah Get current frequency limit */
+ HSMP_GET_PROC_HOT, /* 0Bh Get PROCHOT status */
+ HSMP_SET_XGMI_LINK_WIDTH, /* 0Ch Set max and min width of xGMI Link */
+ HSMP_SET_DF_PSTATE, /* 0Dh Alter APEnable/Disable messages behavior */
+ HSMP_SET_AUTO_DF_PSTATE, /* 0Eh Enable DF P-State Performance Boost algorithm */
+ HSMP_GET_FCLK_MCLK, /* 0Fh Get FCLK and MEMCLK for current socket */
+ HSMP_GET_CCLK_THROTTLE_LIMIT, /* 10h Get CCLK frequency limit in socket */
+ HSMP_GET_C0_PERCENT, /* 11h Get average C0 residency in socket */
+ HSMP_SET_NBIO_DPM_LEVEL, /* 12h Set max/min LCLK DPM Level for a given NBIO */
+ /* 13h Reserved */
+ HSMP_GET_DDR_BANDWIDTH = 0x14, /* 14h Get theoretical maximum and current DDR Bandwidth */
+ HSMP_GET_TEMP_MONITOR, /* 15h Get per-DIMM temperature and refresh rates */
+ HSMP_MSG_ID_MAX,
+};
+
+struct hsmp_message {
+ __u32 msg_id; /* Message ID */
+ __u16 num_args; /* Number of input argument words in message */
+ __u16 response_sz; /* Number of expected output/response words */
+ __u32 args[HSMP_MAX_MSG_LEN]; /* argument/response buffer */
+ __u16 sock_ind; /* socket number */
+};
+
+enum hsmp_msg_type {
+ HSMP_RSVD = -1,
+ HSMP_SET = 0,
+ HSMP_GET = 1,
+};
+
+struct hsmp_msg_desc {
+ int num_args;
+ int response_sz;
+ enum hsmp_msg_type type;
+};
+
+/*
+ * User may use these comments as reference, please find the
+ * supported list of messages and message definition in the
+ * HSMP chapter of respective family/model PPR.
+ *
+ * Not supported messages would return -ENOMSG.
+ */
+static const struct hsmp_msg_desc hsmp_msg_desc_table[] = {
+ /* RESERVED */
+ {0, 0, HSMP_RSVD},
+
+ /*
+ * HSMP_TEST, num_args = 1, response_sz = 1
+ * input: args[0] = xx
+ * output: args[0] = xx + 1
+ */
+ {1, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_SMU_VER, num_args = 0, response_sz = 1
+ * output: args[0] = smu fw ver
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_PROTO_VER, num_args = 0, response_sz = 1
+ * output: args[0] = proto version
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_SOCKET_POWER, num_args = 0, response_sz = 1
+ * output: args[0] = socket power in mWatts
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_SET_SOCKET_POWER_LIMIT, num_args = 1, response_sz = 0
+ * input: args[0] = power limit value in mWatts
+ */
+ {1, 0, HSMP_SET},
+
+ /*
+ * HSMP_GET_SOCKET_POWER_LIMIT, num_args = 0, response_sz = 1
+ * output: args[0] = socket power limit value in mWatts
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_SOCKET_POWER_LIMIT_MAX, num_args = 0, response_sz = 1
+ * output: args[0] = maximuam socket power limit in mWatts
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_SET_BOOST_LIMIT, num_args = 1, response_sz = 0
+ * input: args[0] = apic id[31:16] + boost limit value in MHz[15:0]
+ */
+ {1, 0, HSMP_SET},
+
+ /*
+ * HSMP_SET_BOOST_LIMIT_SOCKET, num_args = 1, response_sz = 0
+ * input: args[0] = boost limit value in MHz
+ */
+ {1, 0, HSMP_SET},
+
+ /*
+ * HSMP_GET_BOOST_LIMIT, num_args = 1, response_sz = 1
+ * input: args[0] = apic id
+ * output: args[0] = boost limit value in MHz
+ */
+ {1, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_PROC_HOT, num_args = 0, response_sz = 1
+ * output: args[0] = proc hot status
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_SET_XGMI_LINK_WIDTH, num_args = 1, response_sz = 0
+ * input: args[0] = min link width[15:8] + max link width[7:0]
+ */
+ {1, 0, HSMP_SET},
+
+ /*
+ * HSMP_SET_DF_PSTATE, num_args = 1, response_sz = 0
+ * input: args[0] = df pstate[7:0]
+ */
+ {1, 0, HSMP_SET},
+
+ /* HSMP_SET_AUTO_DF_PSTATE, num_args = 0, response_sz = 0 */
+ {0, 0, HSMP_SET},
+
+ /*
+ * HSMP_GET_FCLK_MCLK, num_args = 0, response_sz = 2
+ * output: args[0] = fclk in MHz, args[1] = mclk in MHz
+ */
+ {0, 2, HSMP_GET},
+
+ /*
+ * HSMP_GET_CCLK_THROTTLE_LIMIT, num_args = 0, response_sz = 1
+ * output: args[0] = core clock in MHz
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_C0_PERCENT, num_args = 0, response_sz = 1
+ * output: args[0] = average c0 residency
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_SET_NBIO_DPM_LEVEL, num_args = 1, response_sz = 0
+ * input: args[0] = nbioid[23:16] + max dpm level[15:8] + min dpm level[7:0]
+ */
+ {1, 0, HSMP_SET},
+
+ /* RESERVED message */
+ {0, 0, HSMP_RSVD},
+
+ /*
+ * HSMP_GET_DDR_BANDWIDTH, num_args = 0, response_sz = 1
+ * output: args[0] = max bw in Gbps[31:20] + utilised bw in Gbps[19:8] +
+ * bw in percentage[7:0]
+ */
+ {0, 1, HSMP_GET},
+
+ /*
+ * HSMP_GET_TEMP_MONITOR, num_args = 0, response_sz = 1
+ * output: args[0] = temperature in degree celsius. [15:8] integer part +
+ * [7:5] fractional part
+ */
+ {0, 1, HSMP_GET},
+};
+
+/* Reset to default packing */
+#pragma pack()
+
+/* Define unique ioctl command for hsmp msgs using generic _IOWR */
+#define HSMP_BASE_IOCTL_NR 0xF8
+#define HSMP_IOCTL_CMD _IOWR(HSMP_BASE_IOCTL_NR, 0, struct hsmp_message)
+
+#endif /*_ASM_X86_AMD_HSMP_H_*/
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 09f4ab013dfa22b2de5d056212a23a44fe5ec674..0d51011d5d900394f229b2cd0d3fac2bf6f1e16b 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -210,6 +210,19 @@ config AMD_PMC
If you choose to compile this driver as a module the module will be
called amd-pmc.
+config AMD_HSMP
+ tristate "AMD HSMP Driver"
+ depends on AMD_NB && X86_64
+ help
+ The driver provides a way for user space tools to monitor and manage
+ system management functionality on EPYC server CPUs from AMD.
+
+ Host System Management Port (HSMP) interface is a mailbox interface
+ between the x86 core and the System Management Unit (SMU) firmware.
+
+ If you choose to compile this driver as a module the module will be
+ called amd_hsmp.
+
config ADV_SWBUTTON
tristate "Advantech ACPI Software Button Driver"
depends on ACPI && INPUT
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 9527088bba7fa7d02252fe0573eeac33f25afabd..fe4d4c8970efa8072713a2b6b5830ac879bbe7af 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_ACER_WMI) += acer-wmi.o
# AMD
obj-$(CONFIG_AMD_PMC) += amd-pmc.o
+obj-$(CONFIG_AMD_HSMP) += amd_hsmp.o
# Advantech
obj-$(CONFIG_ADV_SWBUTTON) += adv_swbutton.o
diff --git a/drivers/platform/x86/amd_hsmp.c b/drivers/platform/x86/amd_hsmp.c
new file mode 100644
index 0000000000000000000000000000000000000000..a0c54b838c114fa19f22d64738335f31f22b2931
--- /dev/null
+++ b/drivers/platform/x86/amd_hsmp.c
@@ -0,0 +1,425 @@
+// 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
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <asm/amd_hsmp.h>
+#include <asm/amd_nb.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/semaphore.h>
+
+#define DRIVER_NAME "amd_hsmp"
+#define DRIVER_VERSION "1.0"
+
+/* 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
+
+/* Timeout in millsec */
+#define HSMP_MSG_TIMEOUT 100
+#define HSMP_SHORT_SLEEP 1
+
+#define HSMP_WR true
+#define HSMP_RD false
+
+/*
+ * To access specific HSMP mailbox register, s/w writes the SMN address of HSMP mailbox
+ * register into the SMN_INDEX register, and reads/writes the SMN_DATA reg.
+ * Below are required SMN address for HSMP Mailbox register offsets in SMU address space
+ */
+#define SMN_HSMP_MSG_ID 0x3B10534
+#define SMN_HSMP_MSG_RESP 0x3B10980
+#define SMN_HSMP_MSG_DATA 0x3B109E0
+
+#define HSMP_INDEX_REG 0xc4
+#define HSMP_DATA_REG 0xc8
+
+static struct semaphore *hsmp_sem;
+
+static struct miscdevice hsmp_device;
+
+static int amd_hsmp_rdwr(struct pci_dev *root, u32 address,
+ u32 *value, bool write)
+{
+ int ret;
+
+ ret = pci_write_config_dword(root, HSMP_INDEX_REG, address);
+ if (ret)
+ return ret;
+
+ ret = (write ? pci_write_config_dword(root, HSMP_DATA_REG, *value)
+ : pci_read_config_dword(root, HSMP_DATA_REG, value));
+
+ return ret;
+}
+
+/*
+ * Send a message to the HSMP port via PCI-e config space registers.
+ *
+ * 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 pci_dev *root, struct hsmp_message *msg)
+{
+ unsigned long timeout, short_sleep;
+ u32 mbox_status;
+ u32 index;
+ int ret;
+
+ /* Clear the status register */
+ mbox_status = HSMP_STATUS_NOT_READY;
+ ret = amd_hsmp_rdwr(root, SMN_HSMP_MSG_RESP, &mbox_status, HSMP_WR);
+ if (ret) {
+ pr_err("Error %d clearing mailbox status register\n", ret);
+ return ret;
+ }
+
+ index = 0;
+ /* Write any message arguments */
+ while (index < msg->num_args) {
+ ret = amd_hsmp_rdwr(root, SMN_HSMP_MSG_DATA + (index << 2),
+ &msg->args[index], HSMP_WR);
+ if (ret) {
+ pr_err("Error %d writing message argument %d\n", ret, index);
+ return ret;
+ }
+ index++;
+ }
+
+ /* Write the message ID which starts the operation */
+ ret = amd_hsmp_rdwr(root, SMN_HSMP_MSG_ID, &msg->msg_id, HSMP_WR);
+ if (ret) {
+ pr_err("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 = amd_hsmp_rdwr(root, SMN_HSMP_MSG_RESP, &mbox_status, HSMP_RD);
+ if (ret) {
+ pr_err("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)) {
+ return -ETIMEDOUT;
+ } else if (unlikely(mbox_status == HSMP_ERR_INVALID_MSG)) {
+ return -ENOMSG;
+ } else if (unlikely(mbox_status == HSMP_ERR_INVALID_INPUT)) {
+ return -EINVAL;
+ } else if (unlikely(mbox_status != HSMP_STATUS_OK)) {
+ pr_err("Message ID %u 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 = amd_hsmp_rdwr(root, SMN_HSMP_MSG_DATA + (index << 2),
+ &msg->args[index], HSMP_RD);
+ if (ret) {
+ pr_err("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 amd_northbridge *nb;
+ int ret;
+
+ if (!msg)
+ return -EINVAL;
+
+ nb = node_to_amd_nb(msg->sock_ind);
+ if (!nb || !nb->root)
+ return -ENODEV;
+
+ ret = validate_message(msg);
+ if (ret)
+ return ret;
+
+ /*
+ * 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(&hsmp_sem[msg->sock_ind],
+ msecs_to_jiffies(HSMP_MSG_TIMEOUT));
+ if (ret < 0)
+ return ret;
+
+ ret = __hsmp_send_message(nb->root, msg);
+
+ up(&hsmp_sem[msg->sock_ind]);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(hsmp_send_message);
+
+static int hsmp_test(u16 sock_ind, u32 value)
+{
+ struct hsmp_message msg = { 0 };
+ struct amd_northbridge *nb;
+ int ret = -ENODEV;
+
+ nb = node_to_amd_nb(sock_ind);
+ if (!nb || !nb->root)
+ return 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(nb->root, &msg);
+ if (ret)
+ return ret;
+
+ /* Check the response value */
+ if (msg.args[0] != (value + 1)) {
+ pr_err("Socket %d test message failed, Expected 0x%08X, received 0x%08X\n",
+ sock_ind, (value + 1), msg.args[0]);
+ return -EBADE;
+ }
+
+ return ret;
+}
+
+static 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 -EINVAL;
+ 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 -EINVAL;
+ break;
+ case FMODE_READ | FMODE_WRITE:
+ /*
+ * Device is opened in O_RDWR mode
+ * Execute both get/monitor and set/configure commands
+ */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ 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;
+}
+
+static const struct file_operations hsmp_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = hsmp_ioctl,
+ .compat_ioctl = hsmp_ioctl,
+};
+
+static int hsmp_pltdrv_probe(struct platform_device *pdev)
+{
+ int i;
+
+ hsmp_sem = devm_kzalloc(&pdev->dev,
+ (amd_nb_num() * sizeof(struct semaphore)),
+ GFP_KERNEL);
+ if (!hsmp_sem)
+ return -ENOMEM;
+
+ for (i = 0; i < amd_nb_num(); i++)
+ sema_init(&hsmp_sem[i], 1);
+
+ hsmp_device.name = "hsmp_cdev";
+ hsmp_device.minor = MISC_DYNAMIC_MINOR;
+ hsmp_device.fops = &hsmp_fops;
+ hsmp_device.parent = &pdev->dev;
+ hsmp_device.nodename = "hsmp";
+ hsmp_device.mode = 0644;
+
+ return misc_register(&hsmp_device);
+}
+
+static int hsmp_pltdrv_remove(struct platform_device *pdev)
+{
+ misc_deregister(&hsmp_device);
+
+ return 0;
+}
+
+static struct platform_driver amd_hsmp_driver = {
+ .probe = hsmp_pltdrv_probe,
+ .remove = hsmp_pltdrv_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ },
+};
+
+static struct platform_device *amd_hsmp_platdev;
+
+static int __init hsmp_plt_init(void)
+{
+ int ret = -ENODEV;
+ u16 num_sockets;
+ int i;
+
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD || boot_cpu_data.x86 < 0x19) {
+ pr_err("HSMP is not supported on Family:%x model:%x\n",
+ boot_cpu_data.x86, boot_cpu_data.x86_model);
+ return ret;
+ }
+
+ /*
+ * amd_nb_num() returns number of SMN/DF interfaces present in the system
+ * if we have N SMN/DF interfaces that ideally means N sockets
+ */
+ num_sockets = amd_nb_num();
+ if (num_sockets == 0)
+ return ret;
+
+ /* Test the hsmp interface on each socket */
+ for (i = 0; i < num_sockets; i++) {
+ ret = hsmp_test(i, 0xDEADBEEF);
+ if (ret) {
+ pr_err("HSMP is not supported on Fam:%x model:%x\n",
+ boot_cpu_data.x86, boot_cpu_data.x86_model);
+ pr_err("Or Is HSMP disabled in BIOS ?\n");
+ return -EOPNOTSUPP;
+ }
+ }
+
+ ret = platform_driver_register(&amd_hsmp_driver);
+ if (ret)
+ return ret;
+
+ amd_hsmp_platdev = platform_device_alloc(DRIVER_NAME, -1);
+ if (!amd_hsmp_platdev) {
+ ret = -ENOMEM;
+ goto drv_unregister;
+ }
+
+ ret = platform_device_add(amd_hsmp_platdev);
+ if (ret) {
+ platform_device_put(amd_hsmp_platdev);
+ goto drv_unregister;
+ }
+
+ return 0;
+
+drv_unregister:
+ platform_driver_unregister(&amd_hsmp_driver);
+ return ret;
+}
+
+static void __exit hsmp_plt_exit(void)
+{
+ platform_device_unregister(amd_hsmp_platdev);
+ platform_driver_unregister(&amd_hsmp_driver);
+}
+
+device_initcall(hsmp_plt_init);
+module_exit(hsmp_plt_exit);
+
+MODULE_DESCRIPTION("AMD HSMP Platform Interface Driver");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");