[PATCH] acpi, spcr: Make SPCR available to x86

Prarit Bhargava prarit at redhat.com
Mon Feb 12 05:47:57 PST 2018

On 02/12/2018 08:34 AM, Peter Zijlstra wrote:
> On Thu, Jan 18, 2018 at 10:09:51AM -0500, Prarit Bhargava wrote:
>>  config ACPI_SPCR_TABLE
>> +	bool "ACPI Serial Port Console Redirection Support"
>> +	default y if X86
>> +	help
>> +	  Enable support for Serial Port Console Redirection (SPCR) Table.
>> +	  This table provides information about the configuration of the
>> +	  earlycon console.
> I just got asked this by oldconfig, which left me rather puzzled, WTF
> does this do?

Odd -- I thought I had taken care of that :(  My apologies Peter.

ACPI SPCR is used by a vendor to define the serial console for a system.  If
SPCR exists a user can add kernel parameter "earlycon" (no extra kernel
parameters) and the console will work out-of-the-box.

The serial console configuration varies from vendor to vendor.  This takes the
guess-work out of defining a serial console.



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