[PATCH] platform/x86: thinkpad_acpi: do not use PSC mode on Intel platforms

From: Mark Pearson <markpearson@lenovo.com>
To: <markpearson@lenovo.com>
Cc: <hdegoede@redhat.com>, <markgross@kernel.org>,
	<platform-driver-x86@vger.kernel.org>
Subject: [PATCH] platform/x86: thinkpad_acpi: do not use PSC mode on Intel platforms
Date: Wed, 22 Jun 2022 14:13:29 -0400	[thread overview]
Message-ID: <20220622181329.63505-1-markpearson@lenovo.com> (raw)
In-Reply-To: <markpearson@lenovo.com>

PSC platform profile mode is only supported on Linux for AMD platforms.

Some older Intel platforms (e.g T490) are advertising it's capability
as Windows uses it - but on Linux we should only be using MMC profile
for Intel systems.

Add a check to prevent it being enabled incorrectly.

Signed-off-by: Mark Pearson <markpearson@lenovo.com>
---
 drivers/platform/x86/thinkpad_acpi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index e6cb4a14cdd4..be194be43663 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -10548,6 +10548,11 @@ static int tpacpi_dytc_profile_init(struct ibm_init_struct *iibm)
 				dytc_mmc_get_available = true;
 		}
 	} else if (output & BIT(DYTC_FC_PSC)) { /* PSC MODE */
+		/* Support for this only works on AMD platforms */
+		if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) {
+			dbg_printk(TPACPI_DBG_INIT, "PSC not support on Intel platforms\n");
+			return -ENODEV;
+		}
 		dytc_profile_available = DYTC_FUNCMODE_PSC;
 	} else {
 		dbg_printk(TPACPI_DBG_INIT, "No DYTC support available\n");
-- 
2.35.1

