amd-pmc s2idle driver issues

From: Alexander Monakov
Date: Sun Dec 20 2020 - 16:37:28 EST


Hi folks,

I've tried the "platform/x86: amd-pmc: Add AMD platform support for S2Idle"
patch on my Acer Swift SF314-42 laptop (Renoir SoC, Ryzen 4500U CPU) and hit
the following issues:

1. The driver doesn't bind to any device. It has the following binding table:

+static const struct acpi_device_id amd_pmc_acpi_ids[] = {
+ {"AMDI0005", 0},
+ {"AMD0004", 0},
+ { }
+};

This laptop has "AMD0005" instead. Adding it to the list allows the driver to
successfully probe.

2. The debugfs interface does not seem to be very helpful. It shows

SMU FW Info: ffffffff

It's not very informative. The code seems to be fetching SMU version from mmio,
so I guess the file should be saying "FW version" rather than "FW Info", and
then, I think version number is not supposed to be "-1".


(and I'm afraid I cannot use the driver, as there seems to be an issue with
GPU resume: sometimes the screen is frozen or black after resume, so I need
to reboot the laptop :( )

Alexander