1 files changed, 338 insertions, 0 deletions
diff --git a/drivers/platform/x86/amd/hsmp/plat.c b/drivers/platform/x86/amd/hsmp/plat.c
new file mode 100644
index 000000000000..f8e74c0392ba
--- /dev/null
+++ b/drivers/platform/x86/amd/hsmp/plat.c
@@ -0,0 +1,338 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD HSMP Platform Driver
+ * Copyright (c) 2024, AMD.
+ * All Rights Reserved.
+ *
+ * This file provides platform device implementations.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <asm/amd_hsmp.h>
+#include <asm/amd_nb.h>
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+
+#include "hsmp.h"
+
+#define DRIVER_NAME		"amd_hsmp"
+#define DRIVER_VERSION		"2.3"
+
+/*
+ * 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_BASE		0x3B00000
+#define SMN_HSMP_MSG_ID		0x0010534
+#define SMN_HSMP_MSG_ID_F1A_M0H	0x0010934
+#define SMN_HSMP_MSG_RESP	0x0010980
+#define SMN_HSMP_MSG_DATA	0x00109E0
+
+#define HSMP_INDEX_REG		0xc4
+#define HSMP_DATA_REG		0xc8
+
+static struct hsmp_plat_device *hsmp_pdev;
+
+static int amd_hsmp_pci_rdwr(struct hsmp_socket *sock, u32 offset,
+			     u32 *value, bool write)
+{
+	int ret;
+
+	if (!sock->root)
+		return -ENODEV;
+
+	ret = pci_write_config_dword(sock->root, HSMP_INDEX_REG,
+				     sock->mbinfo.base_addr + offset);
+	if (ret)
+		return ret;
+
+	ret = (write ? pci_write_config_dword(sock->root, HSMP_DATA_REG, *value)
+		     : pci_read_config_dword(sock->root, HSMP_DATA_REG, value));
+
+	return ret;
+}
+
+static ssize_t hsmp_metric_tbl_plat_read(struct file *filp, struct kobject *kobj,
+					 struct bin_attribute *bin_attr, char *buf,
+					 loff_t off, size_t count)
+{
+	struct hsmp_socket *sock;
+	u16 sock_ind;
+
+	sock_ind = (uintptr_t)bin_attr->private;
+	if (sock_ind >= hsmp_pdev->num_sockets)
+		return -EINVAL;
+
+	sock = &hsmp_pdev->sock[sock_ind];
+
+	return hsmp_metric_tbl_read(sock, buf, count);
+}
+
+static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
+					 struct bin_attribute *battr, int id)
+{
+	u16 sock_ind;
+
+	sock_ind = (uintptr_t)battr->private;
+
+	if (id == 0 && sock_ind >= hsmp_pdev->num_sockets)
+		return SYSFS_GROUP_INVISIBLE;
+
+	if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6)
+		return battr->attr.mode;
+
+	return 0;
+}
+
+/*
+ * AMD supports maximum of 8 sockets in a system.
+ * Static array of 8 + 1(for NULL) elements is created below
+ * to create sysfs groups for sockets.
+ * is_bin_visible function is used to show / hide the necessary groups.
+ */
+#define HSMP_BIN_ATTR(index, _list)					\
+static struct bin_attribute attr##index = {				\
+	.attr = { .name = HSMP_METRICS_TABLE_NAME, .mode = 0444},	\
+	.private = (void *)index,					\
+	.read = hsmp_metric_tbl_plat_read,					\
+	.size = sizeof(struct hsmp_metric_table),			\
+};									\
+static struct bin_attribute _list[] = {					\
+	&attr##index,							\
+	NULL								\
+}
+
+HSMP_BIN_ATTR(0, *sock0_attr_list);
+HSMP_BIN_ATTR(1, *sock1_attr_list);
+HSMP_BIN_ATTR(2, *sock2_attr_list);
+HSMP_BIN_ATTR(3, *sock3_attr_list);
+HSMP_BIN_ATTR(4, *sock4_attr_list);
+HSMP_BIN_ATTR(5, *sock5_attr_list);
+HSMP_BIN_ATTR(6, *sock6_attr_list);
+HSMP_BIN_ATTR(7, *sock7_attr_list);
+
+#define HSMP_BIN_ATTR_GRP(index, _list, _name)			\
+static struct attribute_group sock##index##_attr_grp = {	\
+	.bin_attrs = _list,					\
+	.is_bin_visible = hsmp_is_sock_attr_visible,		\
+	.name = #_name,						\
+}
+
+HSMP_BIN_ATTR_GRP(0, sock0_attr_list, socket0);
+HSMP_BIN_ATTR_GRP(1, sock1_attr_list, socket1);
+HSMP_BIN_ATTR_GRP(2, sock2_attr_list, socket2);
+HSMP_BIN_ATTR_GRP(3, sock3_attr_list, socket3);
+HSMP_BIN_ATTR_GRP(4, sock4_attr_list, socket4);
+HSMP_BIN_ATTR_GRP(5, sock5_attr_list, socket5);
+HSMP_BIN_ATTR_GRP(6, sock6_attr_list, socket6);
+HSMP_BIN_ATTR_GRP(7, sock7_attr_list, socket7);
+
+static const struct attribute_group *hsmp_groups[] = {
+	&sock0_attr_grp,
+	&sock1_attr_grp,
+	&sock2_attr_grp,
+	&sock3_attr_grp,
+	&sock4_attr_grp,
+	&sock5_attr_grp,
+	&sock6_attr_grp,
+	&sock7_attr_grp,
+	NULL
+};
+
+static inline bool is_f1a_m0h(void)
+{
+	if (boot_cpu_data.x86 == 0x1A && boot_cpu_data.x86_model <= 0x0F)
+		return true;
+
+	return false;
+}
+
+static int init_platform_device(struct device *dev)
+{
+	struct hsmp_socket *sock;
+	int ret, i;
+
+	for (i = 0; i < hsmp_pdev->num_sockets; i++) {
+		if (!node_to_amd_nb(i))
+			return -ENODEV;
+		sock = &hsmp_pdev->sock[i];
+		sock->root			= node_to_amd_nb(i)->root;
+		sock->sock_ind			= i;
+		sock->dev			= dev;
+		sock->mbinfo.base_addr		= SMN_HSMP_BASE;
+		sock->amd_hsmp_rdwr		= amd_hsmp_pci_rdwr;
+
+		/*
+		 * This is a transitional change from non-ACPI to ACPI, only
+		 * family 0x1A, model 0x00 platform is supported for both ACPI and non-ACPI.
+		 */
+		if (is_f1a_m0h())
+			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID_F1A_M0H;
+		else
+			sock->mbinfo.msg_id_off	= SMN_HSMP_MSG_ID;
+
+		sock->mbinfo.msg_resp_off	= SMN_HSMP_MSG_RESP;
+		sock->mbinfo.msg_arg_off	= SMN_HSMP_MSG_DATA;
+		sema_init(&sock->hsmp_sem, 1);
+
+		/* Test the hsmp interface on each socket */
+		ret = hsmp_test(i, 0xDEADBEEF);
+		if (ret) {
+			dev_err(dev, "HSMP test message failed on Fam:%x model:%x\n",
+				boot_cpu_data.x86, boot_cpu_data.x86_model);
+			dev_err(dev, "Is HSMP disabled in BIOS ?\n");
+			return ret;
+		}
+
+		ret = hsmp_cache_proto_ver(i);
+		if (ret) {
+			dev_err(dev, "Failed to read HSMP protocol version\n");
+			return ret;
+		}
+
+		if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6) {
+			ret = hsmp_get_tbl_dram_base(i);
+			if (ret)
+				dev_err(dev, "Failed to init metric table\n");
+		}
+	}
+
+	return 0;
+}
+
+static int hsmp_pltdrv_probe(struct platform_device *pdev)
+{
+	int ret;
+
+	hsmp_pdev->sock = devm_kcalloc(&pdev->dev, hsmp_pdev->num_sockets,
+				       sizeof(*hsmp_pdev->sock),
+				       GFP_KERNEL);
+	if (!hsmp_pdev->sock)
+		return -ENOMEM;
+
+	ret = init_platform_device(&pdev->dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to init HSMP mailbox\n");
+		return ret;
+	}
+
+	return hsmp_misc_register(&pdev->dev);
+}
+
+static void hsmp_pltdrv_remove(struct platform_device *pdev)
+{
+	hsmp_misc_deregister();
+}
+
+static struct platform_driver amd_hsmp_driver = {
+	.probe		= hsmp_pltdrv_probe,
+	.remove		= hsmp_pltdrv_remove,
+	.driver		= {
+		.name	= DRIVER_NAME,
+		.dev_groups = hsmp_groups,
+	},
+};
+
+static struct platform_device *amd_hsmp_platdev;
+
+static int hsmp_plat_dev_register(void)
+{
+	int ret;
+
+	amd_hsmp_platdev = platform_device_alloc(DRIVER_NAME, PLATFORM_DEVID_NONE);
+	if (!amd_hsmp_platdev)
+		return -ENOMEM;
+
+	ret = platform_device_add(amd_hsmp_platdev);
+	if (ret)
+		platform_device_put(amd_hsmp_platdev);
+
+	return ret;
+}
+
+/*
+ * This check is only needed for backward compatibility of previous platforms.
+ * All new platforms are expected to support ACPI based probing.
+ */
+static bool legacy_hsmp_support(void)
+{
+	if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD)
+		return false;
+
+	switch (boot_cpu_data.x86) {
+	case 0x19:
+		switch (boot_cpu_data.x86_model) {
+		case 0x00 ... 0x1F:
+		case 0x30 ... 0x3F:
+		case 0x90 ... 0x9F:
+		case 0xA0 ... 0xAF:
+			return true;
+		default:
+			return false;
+		}
+	case 0x1A:
+		switch (boot_cpu_data.x86_model) {
+		case 0x00 ... 0x1F:
+			return true;
+		default:
+			return false;
+		}
+	default:
+		return false;
+	}
+
+	return false;
+}
+
+static int __init hsmp_plt_init(void)
+{
+	int ret = -ENODEV;
+
+	if (!legacy_hsmp_support()) {
+		pr_info("HSMP is not supported on Family:%x model:%x\n",
+			boot_cpu_data.x86, boot_cpu_data.x86_model);
+		return ret;
+	}
+
+	hsmp_pdev = get_hsmp_pdev();
+	if (!hsmp_pdev)
+		return -ENOMEM;
+
+	/*
+	 * 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
+	 */
+	hsmp_pdev->num_sockets = amd_nb_num();
+	if (hsmp_pdev->num_sockets == 0 || hsmp_pdev->num_sockets > MAX_AMD_SOCKETS)
+		return ret;
+
+	ret = platform_driver_register(&amd_hsmp_driver);
+	if (ret)
+		return ret;
+
+	ret = hsmp_plat_dev_register();
+	if (ret)
+		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_IMPORT_NS(AMD_HSMP);
+MODULE_DESCRIPTION("AMD HSMP Platform Interface Driver");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL");