Re: [PATCH v4 4/7] platform/x86/amd/hsmp: Source metric-table size from firmware
From: M K, Muralidhara
Date: Thu Jun 11 2026 - 13:08:08 EST
On 6/11/2026 1:50 PM, Ilpo Järvinen wrote:
Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.Understood. I will add <include/types.h>
On Thu, 11 Jun 2026, M K, Muralidhara wrote:
On 6/10/2026 4:35 PM, Ilpo Järvinen wrote:
Caution: This message originated from an External Source. Use proper cautionIn hsmp.h, size_t becomes visible without adding anything new, because the
when opening attachments, clicking links, or responding.
On Thu, 28 May 2026, Muralidhara M K wrote:
The driver hard-codes the metric-table region size to
sizeof(struct hsmp_metric_table). That is correct for HSMP protocol
version 6 but mis-sizes the ioremap of the SMU DRAM region on newer
platforms: Family 1Ah Model 50h-5Fh exposes a ~13 KB
hsmp_metric_table_zen6, and the table is expected to keep growing
on future firmware. The same hard-coded value also forces
hsmp_metric_tbl_read() to reject any read that follows the actual
firmware layout.
Pick up the table size from firmware instead. SMU on Family 1Ah
Model 50h and later populates HSMP_GET_METRIC_TABLE_DRAM_ADDR's
args[2] with the DRAM region size in bytes; older firmware leaves
it 0. Bump the descriptor's response_sz to 3 so the field is read,
store the value in hsmp_pdev.hsmp_table_size at probe time, and
fall back to sizeof(struct hsmp_metric_table) when firmware reports
0. Use hsmp_table_size both for the devm_ioremap() of the region
and as the upper bound for hsmp_metric_tbl_read().
Behaviour on existing protocol-version-6 hardware is unchanged:
firmware returns 0, the fallback yields the same value as the
previous hard-coded one, and both the ioremap and the size check
produce the same result as before.
The ioctl interface added later in this series uses the same
hsmp_table_size to validate the userspace request and to copy out
the full firmware-reported region.
Co-developed-by: Muthusamy Ramalingam <muthusamy.ramalingam@xxxxxxx>
Signed-off-by: Muthusamy Ramalingam <muthusamy.ramalingam@xxxxxxx>
Signed-off-by: Muralidhara M K <muralidhara.mk@xxxxxxx>
---
arch/x86/include/uapi/asm/amd_hsmp.h | 5 +++--
drivers/platform/x86/amd/hsmp/hsmp.c | 11 ++++++++---
drivers/platform/x86/amd/hsmp/hsmp.h | 1 +
3 files changed, 12 insertions(+), 5 deletions(-)
diff --git a/arch/x86/include/uapi/asm/amd_hsmp.h
b/arch/x86/include/uapi/asm/amd_hsmp.h
index fce271282348..438ac38d0dc8 100644
--- a/arch/x86/include/uapi/asm/amd_hsmp.h
+++ b/arch/x86/include/uapi/asm/amd_hsmp.h
@@ -365,11 +365,12 @@ 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
diff --git a/drivers/platform/x86/amd/hsmp/hsmp.c
b/drivers/platform/x86/amd/hsmp/hsmp.c
index 9bad58fef304..cf9392f99298 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 +397,14 @@ 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;
Please add types.h include.
file already includes linux/device.h, and that pulls in linux/types.h
Please don't rely on indirect include paths. The rule for includes is
Include What You Use.
There are some exceptions to the general rule such as linux/xx.h
including asm/xx.h, in such case you only need to add linux/xx.h.
--
i.