RE: [EXT] Re: [PATCH RFC net-next 03/19] net: mvpp2: add CM3 SRAM memory map

From: Stefan Chulski
Date: Sun Jan 10 2021 - 12:55:48 EST


>
> > > Should there be -EPROBE_DEFER handling in here somewhere? The SRAM
> > > is a device, so it might not of been probed yet?
> >
>
> > No, firmware probed during bootloader boot and we can use SRAM. SRAM
> > memory can be safely used.
>
> A previous patch added:
>
> + CP11X_LABEL(cm3_sram): cm3@220000 {
> + compatible = "mmio-sram";
> + reg = <0x220000 0x800>;
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges = <0 0x220000 0x800>;
> + };
> +
>
> So it looks like the SRAM is a device, in the linux driver model. And there is a
> driver for this, driver/misc/sram.c. How do you know this device has been
> probed before the Ethernet driver?
>
> Andrew

You right, I would add EPROBE_DEFER if of_gen_pool_get return NULL.

Thanks.