Re: [PATCH] ignore ,keep for efi earlyprintk

Thomas Gleixner
2014-04-29T10:21:14Z

On Tue, 29 Apr 2014, Matt Fleming wrote:
> I would just replace the existing calls to early_ioremap() with
> efi_ioremap() and implement it like so (all in
> arch/x86/platform/efi/early_printk.c),
>
> static void *efi_ioremap(resource_size_t phys_addr, unsigned long size)
> {
> if (system_state == SYSTEM_BOOTING)
> return early_ioremap(phys_addr, size);
>
> return ioremap(phys_addr, size);
> }
>
> At least I think SYSTEM_BOOTING is the correct way to figure out when to
> use early_ioremap(), I'm open to other suggestions though.

ioremap() is available after paging_init() has been called.

Just x86 has this extra bits so you can use early_ioremap/unmap
_AFTER_ paging_init(). No idea why, but probably to cope with some
brilliant init calls which run pre and post paging_init().

Thanks,

tglx