2 files changed, 322 insertions, 31 deletions

diff --git a/drivers/platform/x86/amd/Kconfig b/drivers/platform/x86/amd/Kconfig
index 54753213cc61..f88682d36447 100644
--- a/drivers/platform/x86/amd/Kconfig
+++ b/drivers/platform/x86/amd/Kconfig
@@ -8,7 +8,7 @@ source "drivers/platform/x86/amd/pmc/Kconfig"
 
 config AMD_HSMP
 	tristate "AMD HSMP Driver"
-	depends on AMD_NB && X86_64
+	depends on AMD_NB && X86_64 && ACPI
 	help
 	  The driver provides a way for user space tools to monitor and manage
 	  system management functionality on EPYC server CPUs from AMD.
diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 1245f65f41c0..9dc8e036ed72 100644
--- a/drivers/platform/x86/amd/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp.c
@@ -18,9 +18,11 @@
 #include <linux/pci.h>
 #include <linux/platform_device.h>
 #include <linux/semaphore.h>
+#include <linux/acpi.h>
 
 #define DRIVER_NAME		"amd_hsmp"
-#define DRIVER_VERSION		"2.0"
+#define DRIVER_VERSION		"2.2"
+#define ACPI_HSMP_DEVICE_HID	"AMDI0097"
 
 /* HSMP Status / Error codes */
 #define HSMP_STATUS_NOT_READY	0x00
@@ -54,6 +56,11 @@
 
 #define HSMP_ATTR_GRP_NAME_SIZE	10
 
+/* These are the strings specified in ACPI table */
+#define MSG_IDOFF_STR		"MsgIdOffset"
+#define MSG_ARGOFF_STR		"MsgArgOffset"
+#define MSG_RESPOFF_STR		"MsgRspOffset"
+
 struct hsmp_mbaddr_info {
 	u32 base_addr;
 	u32 msg_id_off;
@@ -66,6 +73,7 @@ struct hsmp_socket {
 	struct bin_attribute hsmp_attr;
 	struct hsmp_mbaddr_info mbinfo;
 	void __iomem *metric_tbl_addr;
+	void __iomem *virt_base_addr;
 	struct semaphore hsmp_sem;
 	char name[HSMP_ATTR_GRP_NAME_SIZE];
 	struct pci_dev *root;
@@ -78,12 +86,14 @@ struct hsmp_plat_device {
 	struct hsmp_socket *sock;
 	u32 proto_ver;
 	u16 num_sockets;
+	bool is_acpi_device;
+	bool is_probed;
 };
 
 static struct hsmp_plat_device plat_dev;
 
-static int amd_hsmp_rdwr(struct hsmp_socket *sock, u32 offset,
-			 u32 *value, bool write)
+static int amd_hsmp_pci_rdwr(struct hsmp_socket *sock, u32 offset,
+			     u32 *value, bool write)
 {
 	int ret;
 
@@ -101,8 +111,29 @@ static int amd_hsmp_rdwr(struct hsmp_socket *sock, u32 offset,
 	return ret;
 }
 
+static void amd_hsmp_acpi_rdwr(struct hsmp_socket *sock, u32 offset,
+			       u32 *value, bool write)
+{
+	if (write)
+		iowrite32(*value, sock->virt_base_addr + offset);
+	else
+		*value = ioread32(sock->virt_base_addr + offset);
+}
+
+static int amd_hsmp_rdwr(struct hsmp_socket *sock, u32 offset,
+			 u32 *value, bool write)
+{
+	if (plat_dev.is_acpi_device)
+		amd_hsmp_acpi_rdwr(sock, offset, value, write);
+	else
+		return amd_hsmp_pci_rdwr(sock, offset, value, write);
+
+	return 0;
+}
+
 /*
- * Send a message to the HSMP port via PCI-e config space registers.
+ * 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.
@@ -349,6 +380,181 @@ static const struct file_operations hsmp_fops = {
 	.compat_ioctl	= hsmp_ioctl,
 };
 
+/* This is the UUID used for HSMP */
+static const guid_t acpi_hsmp_uuid = GUID_INIT(0xb74d619d, 0x5707, 0x48bd,
+						0xa6, 0x9f, 0x4e, 0xa2,
+						0x87, 0x1f, 0xc2, 0xf6);
+
+static inline bool is_acpi_hsmp_uuid(union acpi_object *obj)
+{
+	if (obj->type == ACPI_TYPE_BUFFER && obj->buffer.length == UUID_SIZE)
+		return guid_equal((guid_t *)obj->buffer.pointer, &acpi_hsmp_uuid);
+
+	return false;
+}
+
+static inline int hsmp_get_uid(struct device *dev, u16 *sock_ind)
+{
+	char *uid;
+
+	/*
+	 * UID (ID00, ID01..IDXX) is used for differentiating sockets,
+	 * read it and strip the "ID" part of it and convert the remaining
+	 * bytes to integer.
+	 */
+	uid = acpi_device_uid(ACPI_COMPANION(dev));
+
+	return kstrtou16(uid + 2, 10, sock_ind);
+}
+
+static acpi_status hsmp_resource(struct acpi_resource *res, void *data)
+{
+	struct hsmp_socket *sock = data;
+	struct resource r;
+
+	switch (res->type) {
+	case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
+		if (!acpi_dev_resource_memory(res, &r))
+			return AE_ERROR;
+		if (!r.start || r.end < r.start || !(r.flags & IORESOURCE_MEM_WRITEABLE))
+			return AE_ERROR;
+		sock->mbinfo.base_addr = r.start;
+		sock->mbinfo.size = resource_size(&r);
+		break;
+	case ACPI_RESOURCE_TYPE_END_TAG:
+		break;
+	default:
+		return AE_ERROR;
+	}
+
+	return AE_OK;
+}
+
+static int hsmp_read_acpi_dsd(struct hsmp_socket *sock)
+{
+	struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *guid, *mailbox_package;
+	union acpi_object *dsd;
+	acpi_status status;
+	int ret = 0;
+	int j;
+
+	status = acpi_evaluate_object_typed(ACPI_HANDLE(sock->dev), "_DSD", NULL,
+					    &buf, ACPI_TYPE_PACKAGE);
+	if (ACPI_FAILURE(status)) {
+		dev_err(sock->dev, "Failed to read mailbox reg offsets from DSD table, err: %s\n",
+			acpi_format_exception(status));
+		return -ENODEV;
+	}
+
+	dsd = buf.pointer;
+
+	/* HSMP _DSD property should contain 2 objects.
+	 * 1. guid which is an acpi object of type ACPI_TYPE_BUFFER
+	 * 2. mailbox which is an acpi object of type ACPI_TYPE_PACKAGE
+	 *    This mailbox object contains 3 more acpi objects of type
+	 *    ACPI_TYPE_PACKAGE for holding msgid, msgresp, msgarg offsets
+	 *    these packages inturn contain 2 acpi objects of type
+	 *    ACPI_TYPE_STRING and ACPI_TYPE_INTEGER
+	 */
+	if (!dsd || dsd->type != ACPI_TYPE_PACKAGE || dsd->package.count != 2) {
+		ret = -EINVAL;
+		goto free_buf;
+	}
+
+	guid = &dsd->package.elements[0];
+	mailbox_package = &dsd->package.elements[1];
+	if (!is_acpi_hsmp_uuid(guid) || mailbox_package->type != ACPI_TYPE_PACKAGE) {
+		dev_err(sock->dev, "Invalid hsmp _DSD table data\n");
+		ret = -EINVAL;
+		goto free_buf;
+	}
+
+	for (j = 0; j < mailbox_package->package.count; j++) {
+		union acpi_object *msgobj, *msgstr, *msgint;
+
+		msgobj	= &mailbox_package->package.elements[j];
+		msgstr	= &msgobj->package.elements[0];
+		msgint	= &msgobj->package.elements[1];
+
+		/* package should have 1 string and 1 integer object */
+		if (msgobj->type != ACPI_TYPE_PACKAGE ||
+		    msgstr->type != ACPI_TYPE_STRING ||
+		    msgint->type != ACPI_TYPE_INTEGER) {
+			ret = -EINVAL;
+			goto free_buf;
+		}
+
+		if (!strncmp(msgstr->string.pointer, MSG_IDOFF_STR,
+			     msgstr->string.length)) {
+			sock->mbinfo.msg_id_off = msgint->integer.value;
+		} else if (!strncmp(msgstr->string.pointer, MSG_RESPOFF_STR,
+				    msgstr->string.length)) {
+			sock->mbinfo.msg_resp_off =  msgint->integer.value;
+		} else if (!strncmp(msgstr->string.pointer, MSG_ARGOFF_STR,
+				    msgstr->string.length)) {
+			sock->mbinfo.msg_arg_off = msgint->integer.value;
+		} else {
+			ret = -ENOENT;
+			goto free_buf;
+		}
+	}
+
+	if (!sock->mbinfo.msg_id_off || !sock->mbinfo.msg_resp_off ||
+	    !sock->mbinfo.msg_arg_off)
+		ret = -EINVAL;
+
+free_buf:
+	ACPI_FREE(buf.pointer);
+	return ret;
+}
+
+static int hsmp_read_acpi_crs(struct hsmp_socket *sock)
+{
+	acpi_status status;
+
+	status = acpi_walk_resources(ACPI_HANDLE(sock->dev), METHOD_NAME__CRS,
+				     hsmp_resource, sock);
+	if (ACPI_FAILURE(status)) {
+		dev_err(sock->dev, "Failed to look up MP1 base address from CRS method, err: %s\n",
+			acpi_format_exception(status));
+		return -EINVAL;
+	}
+	if (!sock->mbinfo.base_addr || !sock->mbinfo.size)
+		return -EINVAL;
+
+	/* The mapped region should be un cached */
+	sock->virt_base_addr = devm_ioremap_uc(sock->dev, sock->mbinfo.base_addr,
+					       sock->mbinfo.size);
+	if (!sock->virt_base_addr) {
+		dev_err(sock->dev, "Failed to ioremap MP1 base address\n");
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/* Parse the ACPI table to read the data */
+static int hsmp_parse_acpi_table(struct device *dev, u16 sock_ind)
+{
+	struct hsmp_socket *sock = &plat_dev.sock[sock_ind];
+	int ret;
+
+	sock->sock_ind		= sock_ind;
+	sock->dev		= dev;
+	plat_dev.is_acpi_device	= true;
+
+	sema_init(&sock->hsmp_sem, 1);
+
+	/* Read MP1 base address from CRS method */
+	ret = hsmp_read_acpi_crs(sock);
+	if (ret)
+		return ret;
+
+	/* Read mailbox offsets from DSD table */
+	return hsmp_read_acpi_dsd(sock);
+}
+
 static ssize_t hsmp_metric_tbl_read(struct file *filp, struct kobject *kobj,
 				    struct bin_attribute *bin_attr, char *buf,
 				    loff_t off, size_t count)
@@ -456,7 +662,7 @@ static int hsmp_create_attr_list(struct attribute_group *attr_grp,
 	return hsmp_init_metric_tbl_bin_attr(hsmp_bin_attrs, sock_ind);
 }
 
-static int hsmp_create_sysfs_interface(struct device *dev)
+static int hsmp_create_non_acpi_sysfs_if(struct device *dev)
 {
 	const struct attribute_group **hsmp_attr_grps;
 	struct attribute_group *attr_grp;
@@ -489,13 +695,36 @@ static int hsmp_create_sysfs_interface(struct device *dev)
 	return devm_device_add_groups(dev, hsmp_attr_grps);
 }
 
-static int hsmp_cache_proto_ver(void)
+static int hsmp_create_acpi_sysfs_if(struct device *dev)
+{
+	struct attribute_group *attr_grp;
+	u16 sock_ind;
+	int ret;
+
+	attr_grp = devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
+	if (!attr_grp)
+		return -ENOMEM;
+
+	attr_grp->is_bin_visible = hsmp_is_sock_attr_visible;
+
+	ret = hsmp_get_uid(dev, &sock_ind);
+	if (ret)
+		return ret;
+
+	ret = hsmp_create_attr_list(attr_grp, dev, sock_ind);
+	if (ret)
+		return ret;
+
+	return devm_device_add_group(dev, attr_grp);
+}
+
+static 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	= 0;
+	msg.sock_ind	= sock_ind;
 	msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz;
 
 	ret = hsmp_send_message(&msg);
@@ -536,43 +765,102 @@ static int init_platform_device(struct device *dev)
 	return 0;
 }
 
+static const struct acpi_device_id amd_hsmp_acpi_ids[] = {
+	{ACPI_HSMP_DEVICE_HID, 0},
+	{}
+};
+MODULE_DEVICE_TABLE(acpi, amd_hsmp_acpi_ids);
+
 static int hsmp_pltdrv_probe(struct platform_device *pdev)
 {
+	struct acpi_device *adev;
+	u16 sock_ind = 0;
 	int ret;
 
-	plat_dev.sock = devm_kzalloc(&pdev->dev,
-				     (plat_dev.num_sockets * sizeof(struct hsmp_socket)),
-				     GFP_KERNEL);
-	if (!plat_dev.sock)
-		return -ENOMEM;
-
-	ret = init_platform_device(&pdev->dev);
-	if (ret)
-		return ret;
-
-	plat_dev.hsmp_device.name	= HSMP_CDEV_NAME;
-	plat_dev.hsmp_device.minor	= MISC_DYNAMIC_MINOR;
-	plat_dev.hsmp_device.fops	= &hsmp_fops;
-	plat_dev.hsmp_device.parent	= &pdev->dev;
-	plat_dev.hsmp_device.nodename	= HSMP_DEVNODE_NAME;
-	plat_dev.hsmp_device.mode	= 0644;
+	/*
+	 * On ACPI supported BIOS, there is an ACPI HSMP device added for
+	 * each socket, so the per socket probing, but the memory allocated for
+	 * sockets should be contiguous to access it as an array,
+	 * Hence allocate memory for all the sockets at once instead of allocating
+	 * on each probe.
+	 */
+	if (!plat_dev.is_probed) {
+		plat_dev.sock = devm_kzalloc(&pdev->dev,
+					     (plat_dev.num_sockets * sizeof(struct hsmp_socket)),
+					     GFP_KERNEL);
+		if (!plat_dev.sock)
+			return -ENOMEM;
+	}
+	adev = ACPI_COMPANION(&pdev->dev);
+	if (adev && !acpi_match_device_ids(adev, amd_hsmp_acpi_ids)) {
+		ret = hsmp_get_uid(&pdev->dev, &sock_ind);
+		if (ret)
+			return ret;
+		if (sock_ind >= plat_dev.num_sockets)
+			return -EINVAL;
+		ret = hsmp_parse_acpi_table(&pdev->dev, sock_ind);
+		if (ret) {
+			dev_err(&pdev->dev, "Failed to parse ACPI table\n");
+			return ret;
+		}
+		/* Test the hsmp interface */
+		ret = hsmp_test(sock_ind, 0xDEADBEEF);
+		if (ret) {
+			dev_err(&pdev->dev, "HSMP test message failed on Fam:%x model:%x\n",
+				boot_cpu_data.x86, boot_cpu_data.x86_model);
+			dev_err(&pdev->dev, "Is HSMP disabled in BIOS ?\n");
+			return ret;
+		}
+	} else {
+		ret = init_platform_device(&pdev->dev);
+		if (ret) {
+			dev_err(&pdev->dev, "Failed to init HSMP mailbox\n");
+			return ret;
+		}
+	}
 
-	ret = hsmp_cache_proto_ver();
+	ret = hsmp_cache_proto_ver(sock_ind);
 	if (ret) {
 		dev_err(&pdev->dev, "Failed to read HSMP protocol version\n");
 		return ret;
 	}
 
-	ret = hsmp_create_sysfs_interface(&pdev->dev);
+	if (plat_dev.is_acpi_device)
+		ret = hsmp_create_acpi_sysfs_if(&pdev->dev);
+	else
+		ret = hsmp_create_non_acpi_sysfs_if(&pdev->dev);
 	if (ret)
 		dev_err(&pdev->dev, "Failed to create HSMP sysfs interface\n");
 
-	return misc_register(&plat_dev.hsmp_device);
+	if (!plat_dev.is_probed) {
+		plat_dev.hsmp_device.name	= HSMP_CDEV_NAME;
+		plat_dev.hsmp_device.minor	= MISC_DYNAMIC_MINOR;
+		plat_dev.hsmp_device.fops	= &hsmp_fops;
+		plat_dev.hsmp_device.parent	= &pdev->dev;
+		plat_dev.hsmp_device.nodename	= HSMP_DEVNODE_NAME;
+		plat_dev.hsmp_device.mode	= 0644;
+
+		ret = misc_register(&plat_dev.hsmp_device);
+		if (ret)
+			return ret;
+
+		plat_dev.is_probed = true;
+	}
+
+	return 0;
+
 }
 
 static void hsmp_pltdrv_remove(struct platform_device *pdev)
 {
-	misc_deregister(&plat_dev.hsmp_device);
+	/*
+	 * We register only one misc_device even on multi socket system.
+	 * So, deregister should happen only once.
+	 */
+	if (plat_dev.is_probed) {
+		misc_deregister(&plat_dev.hsmp_device);
+		plat_dev.is_probed = false;
+	}
 }
 
 static struct platform_driver amd_hsmp_driver = {
@@ -580,6 +868,7 @@ static struct platform_driver amd_hsmp_driver = {
 	.remove_new	= hsmp_pltdrv_remove,
 	.driver		= {
 		.name	= DRIVER_NAME,
+		.acpi_match_table = amd_hsmp_acpi_ids,
 	},
 };
 
@@ -622,9 +911,11 @@ static int __init hsmp_plt_init(void)
 	if (ret)
 		return ret;
 
-	ret = hsmp_plat_dev_register();
-	if (ret)
-		platform_driver_unregister(&amd_hsmp_driver);
+	if (!plat_dev.is_acpi_device) {
+		ret = hsmp_plat_dev_register();
+		if (ret)
+			platform_driver_unregister(&amd_hsmp_driver);
+	}
 
 	return ret;
 }