[PATCH v4 1/3] platform/x86/amd/hsmp: create plat specific struct

[PATCH v4 1/3] platform/x86/amd/hsmp: create plat specific struct

[Suma Hegde]

Having a separate platform device structure helps in future, to
contain platform specific variables and other data.

Also, define macros for dev nodes

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
---
Changes since v1:
1. defined HSMP_CDEV_NAME and HSMP_DEVNODE_NAME macros
Changes since v2:
1. moved num_sockets variable to plat_dev structure
Changes since v3:
1. updated commit message


 drivers/platform/x86/amd/hsmp.c | 61 ++++++++++++++++++++-------------
 1 file changed, 38 insertions(+), 23 deletions(-)

diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 31382ef52efb..99727cd705cf 100644
--- a/drivers/platform/x86/amd/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp.c
@@ -47,9 +47,22 @@
 #define HSMP_INDEX_REG		0xc4
 #define HSMP_DATA_REG		0xc8
 
-static struct semaphore *hsmp_sem;
+#define HSMP_CDEV_NAME		"hsmp_cdev"
+#define HSMP_DEVNODE_NAME	"hsmp"
 
-static struct miscdevice hsmp_device;
+struct hsmp_socket {
+	struct semaphore hsmp_sem;
+	u16 sock_ind;
+};
+
+struct hsmp_plat_device {
+	struct miscdevice hsmp_device;
+	struct hsmp_socket *sock;
+	struct device *dev;
+	u16 num_sockets;
+};
+
+static struct hsmp_plat_device plat_dev;
 
 static int amd_hsmp_rdwr(struct pci_dev *root, u32 address,
 			 u32 *value, bool write)
@@ -188,6 +201,7 @@ static int validate_message(struct hsmp_message *msg)
 
 int hsmp_send_message(struct hsmp_message *msg)
 {
+	struct hsmp_socket *sock = &plat_dev.sock[msg->sock_ind];
 	struct amd_northbridge *nb;
 	int ret;
 
@@ -208,14 +222,13 @@ int hsmp_send_message(struct hsmp_message *msg)
 	 * 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));
+	ret = down_timeout(&sock->hsmp_sem, msecs_to_jiffies(HSMP_MSG_TIMEOUT));
 	if (ret < 0)
 		return ret;
 
 	ret = __hsmp_send_message(nb->root, msg);
 
-	up(&hsmp_sem[msg->sock_ind]);
+	up(&sock->hsmp_sem);
 
 	return ret;
 }
@@ -321,28 +334,31 @@ 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)
+	plat_dev.sock = devm_kzalloc(&pdev->dev,
+				     (plat_dev.num_sockets * sizeof(struct hsmp_socket)),
+				     GFP_KERNEL);
+	if (!plat_dev.sock)
 		return -ENOMEM;
+	plat_dev.dev = &pdev->dev;
 
-	for (i = 0; i < amd_nb_num(); i++)
-		sema_init(&hsmp_sem[i], 1);
+	for (i = 0; i < plat_dev.num_sockets; i++) {
+		sema_init(&plat_dev.sock[i].hsmp_sem, 1);
+		plat_dev.sock[i].sock_ind = i;
+	}
 
-	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;
+	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;
 
-	return misc_register(&hsmp_device);
+	return misc_register(&plat_dev.hsmp_device);
 }
 
 static void hsmp_pltdrv_remove(struct platform_device *pdev)
 {
-	misc_deregister(&hsmp_device);
+	misc_deregister(&plat_dev.hsmp_device);
 }
 
 static struct platform_driver amd_hsmp_driver = {
@@ -358,7 +374,6 @@ 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) {
@@ -371,12 +386,12 @@ static int __init hsmp_plt_init(void)
 	 * 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)
+	plat_dev.num_sockets = amd_nb_num();
+	if (plat_dev.num_sockets == 0)
 		return ret;
 
 	/* Test the hsmp interface on each socket */
-	for (i = 0; i < num_sockets; i++) {
+	for (i = 0; i < plat_dev.num_sockets; i++) {
 		ret = hsmp_test(i, 0xDEADBEEF);
 		if (ret) {
 			pr_err("HSMP is not supported on Fam:%x model:%x\n",
-- 
2.25.1

[PATCH v4 2/3] platform/x86/amd/hsmp: add support for metrics tbl

[Suma Hegde]

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>
---
Changes since v1:
1. Remove HSMP_DEVNODE_NAME and HSMP_CDEV_NAME macro definitions in
this patch
2. Remove extra space in comments for HSMP_GET_METRIC_TABLE_VER,
   HSMP_GET_METRIC_TABLE and HSMP_GET_METRIC_TABLE_DRAM_ADDR enum
   definition in amd_hsmp.h files
3. Change check, count == 0 to !count in hsmp_metric_tbl_read() function
4. Add hsmp_metric_table_visible() function
5. hsmp_create_metric_tbl_sysfs_file() is renamed as hsmp_init_metric_tbl_bin_attr()
   and code is also modified slightly
6. Modify hsmp_create_sysfs_file() to use devm_device_add_groups()
7. Change from cleanup label to deregister label
8. Add dev_err print in hsmp_get_tbl_dram_base()
9. Reword "Unable to Failed" in hsmp_get_tbl_dram_base()
10. Add HSMP_GRP_NAME_SIZE and NUM_ATTRS macros
11. Remove sysfs cleanup code in hsmp_pltdrv_remove()
12. Correct ATRR typo error
13. Change sprintf to snprintf
14. Check metrics table support only against HSMP_PROTO_VER6

Changes since v2:
1. squash documentation patch into this patch
2. change from num_sockets to plat_dev.num_sockets

Changes since v3:
1. sysfs_attr_init() to sysfs_bin_attr_init(), errors reported by
   allyesconfig build
2. "C++" style comments in amd_hsmp.h to C style comments, fix errors
   reported by W=1
3. "i" data type to u8 in hsmp_create_sysfs_file(), fix errors reported
   by W=1 
4. remove devm_kzalloc for attr_grp->name in hsmp_create_sysfs_file()
5. rename HSMP_GRP_NAME_SIZE to HSMP_ATTR_GRP_NAME_SIZE and define value
   to 10
6. move hsmp_get_tbl_dram_base() call to hsmp_init_metric_tbl_bin_attr()
7. hsmp_metric_table_visible to hsmp_is_sock_attr_visible
8. use condition check "if (count < bin_attr->size)"
   in hsmp_metric_tbl_read
9. Reorder misc_register and hsmp_cache_proto_ver calls
10. remove devm_kzalloc in hsmp_init_metric_tbl_bin_attr()
11. Wordings in documentation and header and add some more comments in
    the code


 Documentation/arch/x86/amd_hsmp.rst  |  18 +++
 arch/x86/include/uapi/asm/amd_hsmp.h | 109 +++++++++++++++++
 drivers/platform/x86/amd/hsmp.c      | 170 ++++++++++++++++++++++++++-
 3 files changed, 295 insertions(+), 2 deletions(-)

diff --git a/Documentation/arch/x86/amd_hsmp.rst b/Documentation/arch/x86/amd_hsmp.rst
index 440e4b645a1c..72083124b9ca 100644
--- a/Documentation/arch/x86/amd_hsmp.rst
+++ b/Documentation/arch/x86/amd_hsmp.rst
@@ -41,6 +41,24 @@ In-kernel integration:
  * Locking across callers is taken care by the driver.
 
 
+HSMP sysfs interface
+====================
+
+1. Metrics table binary sysfs
+
+AMD MI300A MCM provides GET_METRICS_TABLE message to retrieve
+most of the system management information from SMU in one go.
+
+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
+
+Note: lseek is not supported as entire metrics table is read
+
+Metrics table definitions will be documented as part of Public PPR.
+The same is defined in the amd_hsmp.h header.
+
+
 An example
 ==========
 
diff --git a/arch/x86/include/uapi/asm/amd_hsmp.h b/arch/x86/include/uapi/asm/amd_hsmp.h
index 769b939444ae..fce22686c834 100644
--- a/arch/x86/include/uapi/asm/amd_hsmp.h
+++ b/arch/x86/include/uapi/asm/amd_hsmp.h
@@ -47,6 +47,9 @@ enum hsmp_message_ids {
 	HSMP_SET_PCI_RATE,		/* 20h Control link rate on PCIe devices */
 	HSMP_SET_POWER_MODE,		/* 21h Select power efficiency profile policy */
 	HSMP_SET_PSTATE_MAX_MIN,	/* 22h Set the max and min DF P-State  */
+	HSMP_GET_METRIC_TABLE_VER,	/* 23h Get metrics table version */
+	HSMP_GET_METRIC_TABLE,		/* 24h Get metrics table */
+	HSMP_GET_METRIC_TABLE_DRAM_ADDR,/* 25h Get metrics table dram address */
 	HSMP_MSG_ID_MAX,
 };
 
@@ -64,6 +67,14 @@ enum hsmp_msg_type {
 	HSMP_GET  = 1,
 };
 
+enum hsmp_proto_versions {
+	HSMP_PROTO_VER2	= 2,
+	HSMP_PROTO_VER3,
+	HSMP_PROTO_VER4,
+	HSMP_PROTO_VER5,
+	HSMP_PROTO_VER6
+};
+
 struct hsmp_msg_desc {
 	int num_args;
 	int response_sz;
@@ -295,6 +306,104 @@ static const struct hsmp_msg_desc hsmp_msg_desc_table[] = {
 	 * input: args[0] = min df pstate[15:8] + max df pstate[7:0]
 	 */
 	{1, 0, HSMP_SET},
+
+	/*
+	 * HSMP_GET_METRIC_TABLE_VER, num_args = 0, response_sz = 1
+	 * output: args[0] = metrics table version
+	 */
+	{0, 1, HSMP_GET},
+
+	/*
+	 * HSMP_GET_METRIC_TABLE, num_args = 0, response_sz = 0
+	 */
+	{0, 0, HSMP_GET},
+
+	/*
+	 * HSMP_GET_METRIC_TABLE_DRAM_ADDR, num_args = 0, response_sz = 2
+	 * output: args[0] = lower 32 bits of the address
+	 * output: args[1] = upper 32 bits of the address
+	 */
+	{0, 2, HSMP_GET},
+};
+
+/* Metrics table (supported only with proto version 6) */
+struct hsmp_metric_table {
+	__u32 accumulation_counter;
+
+	/* TEMPERATURE */
+	__u32 max_socket_temperature;
+	__u32 max_vr_temperature;
+	__u32 max_hbm_temperature;
+	__u64 max_socket_temperature_acc;
+	__u64 max_vr_temperature_acc;
+	__u64 max_hbm_temperature_acc;
+
+	/* POWER */
+	__u32 socket_power_limit;
+	__u32 max_socket_power_limit;
+	__u32 socket_power;
+
+	/* ENERGY */
+	__u64 timestamp;
+	__u64 socket_energy_acc;
+	__u64 ccd_energy_acc;
+	__u64 xcd_energy_acc;
+	__u64 aid_energy_acc;
+	__u64 hbm_energy_acc;
+
+	/* FREQUENCY */
+	__u32 cclk_frequency_limit;
+	__u32 gfxclk_frequency_limit;
+	__u32 fclk_frequency;
+	__u32 uclk_frequency;
+	__u32 socclk_frequency[4];
+	__u32 vclk_frequency[4];
+	__u32 dclk_frequency[4];
+	__u32 lclk_frequency[4];
+	__u64 gfxclk_frequency_acc[8];
+	__u64 cclk_frequency_acc[96];
+
+	/* FREQUENCY RANGE */
+	__u32 max_cclk_frequency;
+	__u32 min_cclk_frequency;
+	__u32 max_gfxclk_frequency;
+	__u32 min_gfxclk_frequency;
+	__u32 fclk_frequency_table[4];
+	__u32 uclk_frequency_table[4];
+	__u32 socclk_frequency_table[4];
+	__u32 vclk_frequency_table[4];
+	__u32 dclk_frequency_table[4];
+	__u32 lclk_frequency_table[4];
+	__u32 max_lclk_dpm_range;
+	__u32 min_lclk_dpm_range;
+
+	/* XGMI */
+	__u32 xgmi_width;
+	__u32 xgmi_bitrate;
+	__u64 xgmi_read_bandwidth_acc[8];
+	__u64 xgmi_write_bandwidth_acc[8];
+
+	/* ACTIVITY */
+	__u32 socket_c0_residency;
+	__u32 socket_gfx_busy;
+	__u32 dram_bandwidth_utilization;
+	__u64 socket_c0_residency_acc;
+	__u64 socket_gfx_busy_acc;
+	__u64 dram_bandwidth_acc;
+	__u32 max_dram_bandwidth;
+	__u64 dram_bandwidth_utilization_acc;
+	__u64 pcie_bandwidth_acc[4];
+
+	/* THROTTLERS */
+	__u32 prochot_residency_acc;
+	__u32 ppt_residency_acc;
+	__u32 socket_thm_residency_acc;
+	__u32 vr_thm_residency_acc;
+	__u32 hbm_thm_residency_acc;
+	__u32 spare;
+
+	/* New items at the end to maintain driver compatibility */
+	__u32 gfxclk_frequency[8];
 };
 
 /* Reset to default packing */
diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 99727cd705cf..5d8efff201d3 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 +337,158 @@ 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;
+	u8 i;
+
+	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", 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 +509,16 @@ 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);
 }
 
-- 
2.25.1

Re: [PATCH v4 2/3] platform/x86/amd/hsmp: add support for metrics tbl

[Ilpo Järvinen]

On Thu, 5 Oct 2023, Suma Hegde wrote:

> 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>


> +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;
> +	u8 i;
> +
> +	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++) {

The change for i to u8 seems not very wise given num_sockets still is u16
as it can turn this into an infinite loop.

-- 
 i.

Re: [PATCH v4 2/3] platform/x86/amd/hsmp: add support for metrics tbl

[Hegde, Suma]

On 10/6/2023 6:51 PM, Ilpo Järvinen wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
>
>
> On Thu, 5 Oct 2023, Suma Hegde wrote:
>
>> 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>
>
>> +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;
>> +     u8 i;
>> +
>> +     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++) {
> The change for i to u8 seems not very wise given num_sockets still is u16
> as it can turn this into an infinite loop.

Hi Ilpo,

amd_nb_num() API which we use to identify the number of sockets on a 
node returns u16. So, we used u16 for plat_dev.num_sockets.
u8 should be enough, as present AMD processors support upto 8 sockets on 
a node.

Coming to the warning raised:
We have defined, HSMP_ATTR_GRP_NAME_SIZE as 10bytes, 6 chars for 
'socket', 3 chars for 3digits (socket index) and a null terminator.
Socket index may not need more than 3 digits in the foreseeable future. 
How about, we declare i as u16 and typecast it as (u8) in the snprintf.

         int ret;
-       u8 i;
+       u16 i;

         hsmp_attr_grps = devm_kzalloc(plat_dev.dev, sizeof(struct 
attribute_group *) *
                                   (plat_dev.num_sockets + 1), 
GFP_KERNEL); @@ -449,7 +449,7 @@ static int 
hsmp_create_sysfs_interface(void)
         if (!attr_grp)
                 return -ENOMEM;

-       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE, 
"socket%u", i);
+       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE,
+ "socket%u", (u8)i);
         attr_grp->name = plat_dev.sock[i].name;


Thanks and Regards,

Suma

>
> --
>   i.
>

Re: [PATCH v4 2/3] platform/x86/amd/hsmp: add support for metrics tbl

[Ilpo Järvinen]

[-- Attachment #1: Type: text/plain, Size: 3306 bytes --]

On Mon, 9 Oct 2023, Hegde, Suma wrote:
> On 10/6/2023 6:51 PM, Ilpo Järvinen wrote:
> > On Thu, 5 Oct 2023, Suma Hegde wrote:
> > 
> > > 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>
> > 
> > > +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;
> > > +     u8 i;
> > > +
> > > +     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++) {
> > The change for i to u8 seems not very wise given num_sockets still is u16
> > as it can turn this into an infinite loop.
> 
> Hi Ilpo,
> 
> amd_nb_num() API which we use to identify the number of sockets on a node
> returns u16. So, we used u16 for plat_dev.num_sockets.
> u8 should be enough, as present AMD processors support upto 8 sockets on a
> node.

I wasn't expecting it to fail at the moment, I just don't want to leave a 
silent trap for the future.

> Coming to the warning raised:
> We have defined, HSMP_ATTR_GRP_NAME_SIZE as 10bytes, 6 chars for 'socket', 3
> chars for 3digits (socket index) and a null terminator.
> Socket index may not need more than 3 digits in the foreseeable future. How
> about, we declare i as u16 and typecast it as (u8) in the snprintf.
> 
>         int ret;
> -       u8 i;
> +       u16 i;
> 
>         hsmp_attr_grps = devm_kzalloc(plat_dev.dev, sizeof(struct
> attribute_group *) *
>                                   (plat_dev.num_sockets + 1), GFP_KERNEL); @@
> -449,7 +449,7 @@ static int hsmp_create_sysfs_interface(void)
>         if (!attr_grp)
>                 return -ENOMEM;
> 
> -       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE, "socket%u",
> i);
> +       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE,
> + "socket%u", (u8)i);
>         attr_grp->name = plat_dev.sock[i].name;

This is similarly trappy as it truncates i if num_sockets is > 255.

I suggest you just put this into start of the function:

	/* String formatting is currently limited to u8 sockets */
	if (WARN_ON(plat_dev.num_sockets > U8_MAX))
		return -ERANGE;

to catch the too many sockets case if it is ever going to occur.
And explain in the changelog that u8 is enough for foreseeable future 
and the string formatting triggers a warning if unnecessarily large type 
is passed to snprintf().


-- 
 i.

Re: [PATCH v4 2/3] platform/x86/amd/hsmp: add support for metrics tbl

[Hegde, Suma]

On 10/9/2023 4:53 PM, Ilpo Järvinen wrote:
> Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
>
>
> On Mon, 9 Oct 2023, Hegde, Suma wrote:
>> On 10/6/2023 6:51 PM, Ilpo Järvinen wrote:
>>> On Thu, 5 Oct 2023, Suma Hegde wrote:
>>>
>>>> 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>
>>>> +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;
>>>> +     u8 i;
>>>> +
>>>> +     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++) {
>>> The change for i to u8 seems not very wise given num_sockets still is u16
>>> as it can turn this into an infinite loop.
>> Hi Ilpo,
>>
>> amd_nb_num() API which we use to identify the number of sockets on a node
>> returns u16. So, we used u16 for plat_dev.num_sockets.
>> u8 should be enough, as present AMD processors support upto 8 sockets on a
>> node.
> I wasn't expecting it to fail at the moment, I just don't want to leave a
> silent trap for the future.
>
>> Coming to the warning raised:
>> We have defined, HSMP_ATTR_GRP_NAME_SIZE as 10bytes, 6 chars for 'socket', 3
>> chars for 3digits (socket index) and a null terminator.
>> Socket index may not need more than 3 digits in the foreseeable future. How
>> about, we declare i as u16 and typecast it as (u8) in the snprintf.
>>
>>          int ret;
>> -       u8 i;
>> +       u16 i;
>>
>>          hsmp_attr_grps = devm_kzalloc(plat_dev.dev, sizeof(struct
>> attribute_group *) *
>>                                    (plat_dev.num_sockets + 1), GFP_KERNEL); @@
>> -449,7 +449,7 @@ static int hsmp_create_sysfs_interface(void)
>>          if (!attr_grp)
>>                  return -ENOMEM;
>>
>> -       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE, "socket%u",
>> i);
>> +       snprintf(plat_dev.sock[i].name, HSMP_ATTR_GRP_NAME_SIZE,
>> + "socket%u", (u8)i);
>>          attr_grp->name = plat_dev.sock[i].name;
> This is similarly trappy as it truncates i if num_sockets is > 255.
>
> I suggest you just put this into start of the function:
>
>          /* String formatting is currently limited to u8 sockets */
>          if (WARN_ON(plat_dev.num_sockets > U8_MAX))
>                  return -ERANGE;
>
> to catch the too many sockets case if it is ever going to occur.
> And explain in the changelog that u8 is enough for foreseeable future
> and the string formatting triggers a warning if unnecessarily large type
> is passed to snprintf().
Ok Ilpo, I will add this WARN_ON and send v5 patch set.
>
> --
>   i.

[PATCH v4 3/3] platform/x86/amd/hsmp: improve the error log

[Suma Hegde]

1. Change print message during platform init to a more meaningful
   clear message.
2. Return the error code returned by hsmp_test() itself, rather then
   returning a common EOPNOTSUPP error.

Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Reviewed-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
---
changes since v3:
none

 drivers/platform/x86/amd/hsmp.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 5d8efff201d3..9a887243e5a4 100644
--- a/drivers/platform/x86/amd/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp.c
@@ -560,10 +560,10 @@ static int __init hsmp_plt_init(void)
 	for (i = 0; i < plat_dev.num_sockets; i++) {
 		ret = hsmp_test(i, 0xDEADBEEF);
 		if (ret) {
-			pr_err("HSMP is not supported on Fam:%x model:%x\n",
+			pr_err("HSMP test message failed 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;
+			pr_err("Is HSMP disabled in BIOS ?\n");
+			return ret;
 		}
 	}
 
-- 
2.25.1