Re: [PATCH -next 1/2] i2c: designware: Switch from using MMIO access to SMN access

From: Borislav Petkov
Date: Mon Jan 16 2023 - 16:59:53 EST


On Mon, Jan 16, 2023 at 11:19:00AM +0100, Jan Dąbroś wrote:
> It's not enough for running init_amd_nbs() to have only
> pci_arch_init() done. We need the pci bus to be created and registered
> with all devices found on the bus.

And when is that done and ready? pci_scan_bus()?

Lemme see if I understand the ordering correctly:

1. PCI needs to be initialized and all devices on the bus registered

2. AMD NB needs to run and enumerate the NBs so that the SMN access which you
need, can work.

3. acpi_scan_init()

4. i2c-designware-platdrv registration

Close?

Now, Mario, remind me again, pls, why can't they use the MSR to get the PSP MMIO
base. It has changed but why?

Maybe we should talk offlist first.

Thx.

--
Regards/Gruss,
Boris.

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