[PATCH v2 5/7] platform/x86/amd/hsmp: Add dynamic table size for metric table

[Muralidhara M K <muralidhara.mk@amd.com>]

Prepare the metric table infrastructure for supporting variable-sized
tables used by different processor families.

- Add hsmp_table_size to hsmp_plat_device for runtime table size
  configuration.
- Update the HSMP_GET_METRIC_TABLE_DRAM_ADDR message descriptor
  response_sz from 2 to 3 to read the new args[2] field that carries
  the DRAM region size in bytes.
- Use msg.args[2] from SMU to set hsmp_pdev.hsmp_table_size directly.
  For older firmware that does not populate args[2] (returns 0), fall
  back to sizeof(struct hsmp_metric_table) for backward compatibility.
- Use hsmp_pdev.hsmp_table_size for ioremap and size validation
  instead of hard-coding sizeof(struct hsmp_metric_table).
- Add a bin_size callback in both acpi.c and plat.c that returns
  hsmp_table_size, overriding the static bin_attribute .size at sysfs
  group registration time so that i_size reflects the actual table
  size reported by SMU.

This makes future processor support automatic as long as SMU reports
the correct DRAM size.

Co-developed-by: Muthusamy Ramalingam <muthusamy.ramalingam@amd.com>
Signed-off-by: Muthusamy Ramalingam <muthusamy.ramalingam@amd.com>
Signed-off-by: Muralidhara M K <muralidhara.mk@amd.com>
---
Changes v1->v2: New Patch

 arch/x86/include/uapi/asm/amd_hsmp.h |  5 +++--
 drivers/platform/x86/amd/hsmp/acpi.c |  7 +++++++
 drivers/platform/x86/amd/hsmp/hsmp.c | 10 +++++++---
 drivers/platform/x86/amd/hsmp/hsmp.h |  1 +
 drivers/platform/x86/amd/hsmp/plat.c |  7 +++++++
 5 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/uapi/asm/amd_hsmp.h b/arch/x86/include/uapi/asm/amd_hsmp.h
index da3e3bbfa33e..b86bbc929395 100644
--- a/arch/x86/include/uapi/asm/amd_hsmp.h
+++ b/arch/x86/include/uapi/asm/amd_hsmp.h
@@ -342,11 +342,12 @@ static const struct hsmp_msg_desc hsmp_msg_desc_table[]
 	{0, 0, HSMP_GET},
 
 	/*
-	 * HSMP_GET_METRIC_TABLE_DRAM_ADDR, num_args = 0, response_sz = 2
+	 * HSMP_GET_METRIC_TABLE_DRAM_ADDR, num_args = 0, response_sz = 3
 	 * output: args[0] = lower 32 bits of the address
 	 * output: args[1] = upper 32 bits of the address
+	 * output: args[2] = DRAM region size in bytes
 	 */
-	{0, 2, HSMP_GET},
+	{0, 3, HSMP_GET},
 
 	/*
 	 * HSMP_SET_XGMI_PSTATE_RANGE, num_args = 1, response_sz = 0/1
diff --git a/drivers/platform/x86/amd/hsmp/acpi.c b/drivers/platform/x86/amd/hsmp/acpi.c
index 8044df862275..f3cfc99ef73d 100644
--- a/drivers/platform/x86/amd/hsmp/acpi.c
+++ b/drivers/platform/x86/amd/hsmp/acpi.c
@@ -250,6 +250,12 @@ static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
 	return 0;
 }
 
+static size_t hsmp_metric_tbl_bin_size(struct kobject *kobj,
+				       const struct bin_attribute *battr, int id)
+{
+	return hsmp_pdev->hsmp_table_size;
+}
+
 static umode_t hsmp_is_sock_dev_attr_visible(struct kobject *kobj,
 					     struct attribute *attr, int id)
 {
@@ -563,6 +569,7 @@ static const struct attribute_group hsmp_attr_grp = {
 	.attrs = hsmp_dev_attr_list,
 	.is_bin_visible = hsmp_is_sock_attr_visible,
 	.is_visible = hsmp_is_sock_dev_attr_visible,
+	.bin_size = hsmp_metric_tbl_bin_size,
 };
 
 static const struct attribute_group *hsmp_groups[] = {
diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c b/drivers/platform/x86/amd/hsmp/hsmp.c
index 9bad58fef304..d6e377078182 100644
--- a/drivers/platform/x86/amd/hsmp/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp/hsmp.c
@@ -356,8 +356,7 @@ ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size)
 		return -ENOMEM;
 	}
 
-	/* Do not support lseek(), also don't allow more than the size of metric table */
-	if (size != sizeof(struct hsmp_metric_table)) {
+	if (size != hsmp_pdev.hsmp_table_size) {
 		dev_err(sock->dev, "Wrong buffer size\n");
 		return -EINVAL;
 	}
@@ -398,8 +397,13 @@ int hsmp_get_tbl_dram_base(u16 sock_ind)
 		dev_err(sock->dev, "Invalid DRAM address for metric table\n");
 		return -ENOMEM;
 	}
+	/* SMU returns table size from Family 1Ah Model 50h and forward */
+	if (msg.args[2])
+		hsmp_pdev.hsmp_table_size = msg.args[2];
+	else
+		hsmp_pdev.hsmp_table_size = sizeof(struct hsmp_metric_table);
 	sock->metric_tbl_addr = devm_ioremap(sock->dev, dram_addr,
-					     sizeof(struct hsmp_metric_table));
+					     hsmp_pdev.hsmp_table_size);
 	if (!sock->metric_tbl_addr) {
 		dev_err(sock->dev, "Failed to ioremap metric table addr\n");
 		return -ENOMEM;
diff --git a/drivers/platform/x86/amd/hsmp/hsmp.h b/drivers/platform/x86/amd/hsmp/hsmp.h
index b153527e0a0d..e7f051475728 100644
--- a/drivers/platform/x86/amd/hsmp/hsmp.h
+++ b/drivers/platform/x86/amd/hsmp/hsmp.h
@@ -55,6 +55,7 @@ struct hsmp_plat_device {
 	u32 proto_ver;
 	u16 num_sockets;
 	bool is_probed;
+	size_t hsmp_table_size;
 };
 
 int hsmp_cache_proto_ver(u16 sock_ind);
diff --git a/drivers/platform/x86/amd/hsmp/plat.c b/drivers/platform/x86/amd/hsmp/plat.c
index e07f68575055..d8dd90dfeb4e 100644
--- a/drivers/platform/x86/amd/hsmp/plat.c
+++ b/drivers/platform/x86/amd/hsmp/plat.c
@@ -62,6 +62,12 @@ static ssize_t hsmp_metric_tbl_plat_read(struct file *filp, struct kobject *kobj
 	return hsmp_metric_tbl_read(sock, buf, count);
 }
 
+static size_t hsmp_metric_tbl_bin_size(struct kobject *kobj,
+				       const struct bin_attribute *battr, int id)
+{
+	return hsmp_pdev->hsmp_table_size;
+}
+
 static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
 					 const struct bin_attribute *battr, int id)
 {
@@ -114,6 +120,7 @@ HSMP_BIN_ATTR(7, *sock7_attr_list);
 static const struct attribute_group sock##index##_attr_grp = {	\
 	.bin_attrs = _list,					\
 	.is_bin_visible = hsmp_is_sock_attr_visible,		\
+	.bin_size = hsmp_metric_tbl_bin_size,			\
 	.name = #_name,						\
 }
 
-- 
2.34.1