Re: [PATCH 5/6] MIPS: implement architecture dependent 'pci_remap_iospace()'

[Arnd Bergmann]

On Fri, Sep 24, 2021 at 11:11 PM Sergio Paracuellos
<sergio.paracuellos@xxxxxxxxx> wrote:
>
> To make PCI IO work we need to properly virtually map IO cpu physical address
> and set this virtual address as the address of the first PCI IO port which
> is set using function 'set_io_port_base()'.
>
> Signed-off-by: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>

> +int pci_remap_iospace(const struct resource *res, phys_addr_t phys_addr)
> +{
> +       size_t size = (res->end - res->start) + 1;
> +       unsigned long vaddr = (unsigned long)ioremap(phys_addr, size);
> +
> +       set_io_port_base(vaddr);
> +       return 0;
> +}

It might be good to check that res->start is zero here, otherwise
the io_port_base would be off. That could happen if you ever have more
than one bridge.

        Arnd