[PATCH v10 3/4] ARM64: ACPI: enable ACPI_SPCR_TABLE

Mark Salter msalter at redhat.com
Tue Sep 13 11:45:56 PDT 2016


On Fri, 2016-09-09 at 17:28 +0800, Hanjun Guo wrote:
> On 2016/9/9 0:34, Mark Salter wrote:
> > 
> > On Thu, 2016-09-08 at 12:16 +0100, Will Deacon wrote:
> > > 
> > > On Wed, Sep 07, 2016 at 12:30:19PM +0300, Aleksey Makarov wrote:
> > > > 
> > > > 
> > > > 
> > > > On 09/05/2016 03:36 PM, Aleksey Makarov wrote:
> > > > > 
> > > > > 
> > > > > SBBR mentions SPCR as a mandatory ACPI table.  So enable it for ARM64
> > > > > 
> > > > > Earlycon should be set up as early as possible.  ACPI boot tables are
> > > > > mapped in arch/arm64/kernel/acpi.c:acpi_boot_table_init() that
> > > > > is called from setup_arch() and that's where we parse SPCR.
> > > > > So it has to be opted-in per-arch.
> > > > > 
> > > > > When ACPI_SPCR_TABLE is defined initialization of DT earlycon is
> > > > > deferred until the DT/ACPI decision is done.  Initialize DT earlycon
> > > > > if ACPI is disabled.
> > > > Hi Will, Catalin,
> > > > 
> > > > Can you review this patch and consider ACKing it please?
> > > Hanjun, Al, Mark, Graeme -- any comments on this?
> > > 
> > > Will
> > I think there is a problem still with systems using 32-bit access to 8250
> > UARTs (i.e. Mustang) but that will need a DBG2 table spec change and
> > followup patch to resolve.
> Hmm, I think you mean we can add patches later with the spec updated,
> and this patch works with SBSA pl011 can go for now?

Yes, I think this series is fine for now.

> 
> Thanks
> Hanjun




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