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platform/x86/amd/hsmp: Enable protocol version 7 metric tables on the ACPI driver

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The ACPI driver currently prepares the per-socket metric table only
on HSMP_PROTO_VER6. With protocol version 7 in use on Family 1Ah
Model 50h-5Fh, userspace cannot reach the larger ~13 KB table:
hsmp_get_tbl_dram_base() is skipped, sock->metric_tbl_addr stays
NULL, and the ioctl added earlier in this series has nothing to read.

Widen the proto_ver gate in init_acpi() from '== HSMP_PROTO_VER6'
to '>= HSMP_PROTO_VER6' so the DRAM region is mapped and
sock->metric_tbl_size is populated on protocol version 7 (and any
future compatible version), making the ioctl path functional.

hsmp_metric_tbl_acpi_read() now returns -EOPNOTSUPP whenever the
running protocol version is not VER6, because the sysfs binary
attribute cannot carry a table larger than PAGE_SIZE. Version 7
userspace gets a clear, actionable error and a documented pointer to
HSMP_IOCTL_GET_TELEMETRY_DATA; version 6 userspace sees no change.

The non-ACPI plat.c path is intentionally left untouched: it covers
Family 1Ah Model 0h-Fh hardware fixed at protocol version 6, where
the existing metrics_bin remains the supported interface.

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>
Link: https://patch.msgid.link/20260727141542.3370108-6-muralidhara.mk@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
This commit is contained in:
Muralidhara M K 2026-07-27 19:45:42 +05:30 committed by Ilpo Järvinen
parent 5273183b63
commit aca39607c1
No known key found for this signature in database
GPG Key ID: 59AC4F6153E5CE31
1 changed files with 20 additions and 2 deletions
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22
drivers/platform/x86/amd/hsmp/acpi.c
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@ -277,13 +277,31 @@ static ssize_t hsmp_metric_tbl_acpi_read(struct file *filp, struct kobject *kobj
struct device *dev = container_of(kobj, struct device, kobj);
struct hsmp_socket *sock = dev_get_drvdata(dev);
/*
* metrics_bin is a sysfs binary attribute and is capped at PAGE_SIZE.
* It can therefore only carry the protocol version 6 metric table
* (struct hsmp_metric_table). The larger tables defined from protocol
* version 7 onwards do not fit; userspace on those systems must read
* the snapshot through HSMP_IOCTL_GET_TELEMETRY_DATA on /dev/hsmp.
* Surface the unsupported case here as -EOPNOTSUPP rather than
* silently truncating the snapshot.
*/
if (hsmp_pdev->proto_ver != HSMP_PROTO_VER6)
return -EOPNOTSUPP;
return hsmp_metric_tbl_read(sock, buf, count);
}
static umode_t hsmp_is_sock_attr_visible(struct kobject *kobj,
const struct bin_attribute *battr, int id)
{
if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6)
/*
* Keep metrics_bin visible on protocol version 7 and later as well,
* so that userspace which expects the file to exist gets a clear
* -EOPNOTSUPP from the read handler instead of -ENOENT, and is
* pointed at HSMP_IOCTL_GET_TELEMETRY_DATA as the supported path.
*/
if (hsmp_pdev->proto_ver >= HSMP_PROTO_VER6)
return battr->attr.mode;
return 0;
@ -539,7 +557,7 @@ static int init_acpi(struct device *dev)
return ret;
}
if (hsmp_pdev->proto_ver == HSMP_PROTO_VER6) {
if (hsmp_pdev->proto_ver >= HSMP_PROTO_VER6) {
ret = hsmp_get_tbl_dram_base(sock_ind);
if (ret)
dev_info(dev, "Failed to init metric table\n");