[PATCH v2] platform/x86/amd: Don't allow HSMP to be loaded on non-server hardware

From: Mario Limonciello
Date: Tue Apr 16 2024 - 14:21:32 EST


From: Mario Limonciello <mario.limonciello@xxxxxxx>

If the HSMP driver is compiled into the kernel or a module manually loaded
on client hardware it can cause problems with the functionality of the PMC
module since it probes a mailbox with a different definition on servers.

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2414
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3285
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
---
v1->v2:
* use pm preferred profile instead
---
drivers/platform/x86/amd/hsmp.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/platform/x86/amd/hsmp.c b/drivers/platform/x86/amd/hsmp.c
index 1927be901108..102a49c3e945 100644
--- a/drivers/platform/x86/amd/hsmp.c
+++ b/drivers/platform/x86/amd/hsmp.c
@@ -907,6 +907,17 @@ static int hsmp_plat_dev_register(void)
return ret;
}

+static bool hsmp_supported_profile(void)
+{
+ switch (acpi_gbl_FADT.preferred_profile) {
+ case PM_ENTERPRISE_SERVER:
+ case PM_SOHO_SERVER:
+ case PM_PERFORMANCE_SERVER:
+ return true;
+ }
+ return false;
+}
+
static int __init hsmp_plt_init(void)
{
int ret = -ENODEV;
@@ -917,6 +928,11 @@ static int __init hsmp_plt_init(void)
return ret;
}

+ if (!hsmp_supported_profile()) {
+ pr_err("HSMP is only supported on servers");
+ return ret;
+ }
+
/*
* 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
--
2.43.0