platform/x86/amd/hsmp: add support for metrics tbl

AMD MI300 MCM provides GET_METRICS_TABLE message to retrieve
all the system management information from SMU.

The metrics table is made available as hexadecimal sysfs binary file
under per socket sysfs directory created at
/sys/devices/platform/amd_hsmp/socket%d/metrics_bin

Metrics table definitions will be documented as part of Public PPR.
The same is defined in the amd_hsmp.h header.

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
Link: https://lore.kernel.org/r/20231010120310.3464066-2-suma.hegde@amd.com
[ij: lseek -> lseek(), dram -> DRAM in dev_err()]
[ij: added period to terminate a documentation sentence]
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

1 files changed, 172 insertions, 2 deletions

diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 99727cd705cf..af8adfbd9369 100644
--- a/drivers/platform/x86/amd/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp.c
@@ -20,7 +20,7 @@
 #include <linux/semaphore.h>
 
 #define DRIVER_NAME		"amd_hsmp"
-#define DRIVER_VERSION		"1.0"
+#define DRIVER_VERSION		"2.0"
 
 /* HSMP Status / Error codes */
 #define HSMP_STATUS_NOT_READY	0x00
@@ -49,9 +49,15 @@
 
 #define HSMP_CDEV_NAME		"hsmp_cdev"
 #define HSMP_DEVNODE_NAME	"hsmp"
+#define HSMP_METRICS_TABLE_NAME	"metrics_bin"
+
+#define HSMP_ATTR_GRP_NAME_SIZE	10
 
 struct hsmp_socket {
+	struct bin_attribute hsmp_attr;
+	void __iomem *metric_tbl_addr;
 	struct semaphore hsmp_sem;
+	char name[HSMP_ATTR_GRP_NAME_SIZE];
 	u16 sock_ind;
 };
 
@@ -59,6 +65,7 @@ struct hsmp_plat_device {
 	struct miscdevice hsmp_device;
 	struct hsmp_socket *sock;
 	struct device *dev;
+	u32 proto_ver;
 	u16 num_sockets;
 };
 
@@ -330,9 +337,162 @@ static const struct file_operations hsmp_fops = {
 	.compat_ioctl	= hsmp_ioctl,
 };
 
+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)
+{
+	struct hsmp_socket *sock = bin_attr->private;
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	/* Do not support lseek(), reads entire metric table */
+	if (count < bin_attr->size) {
+		dev_err(plat_dev.dev, "Wrong buffer size\n");
+		return -EINVAL;
+	}
+
+	if (!sock) {
+		dev_err(plat_dev.dev, "Failed to read attribute private data\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(buf, sock->metric_tbl_addr, bin_attr->size);
+
+	return bin_attr->size;
+}
+
+static int hsmp_get_tbl_dram_base(u16 sock_ind)
+{
+	struct hsmp_socket *sock = &plat_dev.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(plat_dev.dev, "Invalid DRAM address for metric table\n");
+		return -ENOMEM;
+	}
+	sock->metric_tbl_addr = devm_ioremap(plat_dev.dev, dram_addr,
+					     sizeof(struct hsmp_metric_table));
+	if (!sock->metric_tbl_addr) {
+		dev_err(plat_dev.dev, "Failed to ioremap metric table addr\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
+					 struct bin_attribute *battr, int id)
+{
+	if (plat_dev.proto_ver == HSMP_PROTO_VER6)
+		return battr->attr.mode;
+	else
+		return 0;
+}
+
+static int hsmp_init_metric_tbl_bin_attr(struct bin_attribute **hattrs, u16 sock_ind)
+{
+	struct bin_attribute *hattr = &plat_dev.sock[sock_ind].hsmp_attr;
+
+	sysfs_bin_attr_init(hattr);
+	hattr->attr.name	= HSMP_METRICS_TABLE_NAME;
+	hattr->attr.mode	= 0444;
+	hattr->read		= hsmp_metric_tbl_read;
+	hattr->size		= sizeof(struct hsmp_metric_table);
+	hattr->private		= &plat_dev.sock[sock_ind];
+	hattrs[0]		= hattr;
+
+	if (plat_dev.proto_ver == HSMP_PROTO_VER6)
+		return (hsmp_get_tbl_dram_base(sock_ind));
+	else
+		return 0;
+}
+
+/* One bin sysfs for metrics table*/
+#define NUM_HSMP_ATTRS		1
+
+static int hsmp_create_sysfs_interface(void)
+{
+	const struct attribute_group **hsmp_attr_grps;
+	struct bin_attribute **hsmp_bin_attrs;
+	struct attribute_group *attr_grp;
+	int ret;
+	u16 i;
+
+	/* String formatting is currently limited to u8 sockets */
+	if (WARN_ON(plat_dev.num_sockets > U8_MAX))
+		return -ERANGE;
+
+	hsmp_attr_grps = devm_kzalloc(plat_dev.dev, sizeof(struct attribute_group *) *
+				      (plat_dev.num_sockets + 1), GFP_KERNEL);
+	if (!hsmp_attr_grps)
+		return -ENOMEM;
+
+	/* Create a sysfs directory for each socket */
+	for (i = 0; i < plat_dev.num_sockets; i++) {
+		attr_grp = devm_kzalloc(plat_dev.dev, sizeof(struct attribute_group), GFP_KERNEL);
+		if (!attr_grp)
+			return -ENOMEM;
+
+		snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE, "socket%u", (u8)i);
+		attr_grp->name = plat_dev.sock[i].name;
+
+		/* Null terminated list of attributes */
+		hsmp_bin_attrs = devm_kzalloc(plat_dev.dev, sizeof(struct bin_attribute *) *
+					      (NUM_HSMP_ATTRS + 1), GFP_KERNEL);
+		if (!hsmp_bin_attrs)
+			return -ENOMEM;
+
+		attr_grp->bin_attrs		= hsmp_bin_attrs;
+		attr_grp->is_bin_visible	= hsmp_is_sock_attr_visible;
+		hsmp_attr_grps[i]		= attr_grp;
+
+		/* Now create the leaf nodes */
+		ret = hsmp_init_metric_tbl_bin_attr(hsmp_bin_attrs, i);
+		if (ret)
+			return ret;
+	}
+	return devm_device_add_groups(plat_dev.dev, hsmp_attr_grps);
+}
+
+static int hsmp_cache_proto_ver(void)
+{
+	struct hsmp_message msg = { 0 };
+	int ret;
+
+	msg.msg_id	= HSMP_GET_PROTO_VER;
+	msg.sock_ind	= 0;
+	msg.response_sz = hsmp_msg_desc_table[HSMP_GET_PROTO_VER].response_sz;
+
+	ret = hsmp_send_message(&msg);
+	if (!ret)
+		plat_dev.proto_ver = msg.args[0];
+
+	return ret;
+}
+
 static int hsmp_pltdrv_probe(struct platform_device *pdev)
 {
-	int i;
+	int ret, i;
 
 	plat_dev.sock = devm_kzalloc(&pdev->dev,
 				     (plat_dev.num_sockets * sizeof(struct hsmp_socket)),
@@ -353,6 +513,16 @@ static int hsmp_pltdrv_probe(struct platform_device *pdev)
 	plat_dev.hsmp_device.nodename	= HSMP_DEVNODE_NAME;
 	plat_dev.hsmp_device.mode	= 0644;
 
+	ret = hsmp_cache_proto_ver();
+	if (ret) {
+		dev_err(plat_dev.dev, "Failed to read HSMP protocol version\n");
+		return ret;
+	}
+
+	ret = hsmp_create_sysfs_interface();
+	if (ret)
+		dev_err(plat_dev.dev, "Failed to create HSMP sysfs interface\n");
+
 	return misc_register(&plat_dev.hsmp_device);
 }