Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752614AbcLFVea (ORCPT ); Tue, 6 Dec 2016 16:34:30 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:33765 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751790AbcLFVe2 (ORCPT ); Tue, 6 Dec 2016 16:34:28 -0500 MIME-Version: 1.0 In-Reply-To: References: <20161206175830.6989-1-aleksey.makarov@linaro.org> <20161206175830.6989-4-aleksey.makarov@linaro.org> From: "Rafael J. Wysocki" Date: Tue, 6 Dec 2016 22:19:06 +0100 X-Google-Sender-Auth: XB9LFo7fyVaIHPEZAZcFI7-VkbI Message-ID: Subject: Re: [RFC v2 3/4] ACPI: DBG2: add 16550 UART with 32-bit access To: Jon Masters Cc: "Rafael J. Wysocki" , Aleksey Makarov , "Rafael J . Wysocki" , ACPI Devel Maling List , "linux-serial@vger.kernel.org" , Linux Kernel Mailing List , Greg Kroah-Hartman , Russell King , Peter Hurley , Mark Salter , Duc Dang , Rob Herring , Robert Moore , Lv Zheng , "Rafael J. Wysocki" , Len Brown , "devel@acpica.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1931 Lines: 50 On Tue, Dec 6, 2016 at 10:15 PM, Jon Masters wrote: > Quick note - specifically, Rafael, this is not currently part of the SPCR specification and > should not be considered for inclusion in Linux until that is decided. Once it is determined > what the fix for SPCR is, that should then be driven into the component architecture and > proposed here. OK, good to know, thanks! > -- > Computer Architect | Sent from my 64-bit #ARM Powered phone > >> On Dec 6, 2016, at 16:00, Rafael J. Wysocki wrote: >> >> On Tue, Dec 6, 2016 at 6:58 PM, Aleksey Makarov >> wrote: >>> It was suggested to add a new Microsoft Debug Port Table 2 >>> (DBG2) (the table used to enumerate the various subtypes of serial >>> port covered by the SPCR) 16550 UART subtype that may be needed for >>> some additional platforms, such as those based upon AppliedMicro >>> X-Gene ARMv8 SoCs. This new subtype would be 16550-compatible >>> with 32-bit access. There already exists 32-bit variant >>> ACPI_DBG2_ARM_SBSA_32BIT of SBSA console ACPI_DBG2_ARM_SBSA_GENERIC. >>> >>> This patch introduces it to Linux kernel. >>> >>> Signed-off-by: Aleksey Makarov >>> --- >>> include/acpi/actbl2.h | 1 + >>> 1 file changed, 1 insertion(+) >>> >>> diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h >>> index c93dbad..f219b04 100644 >>> --- a/include/acpi/actbl2.h >>> +++ b/include/acpi/actbl2.h >>> @@ -371,6 +371,7 @@ struct acpi_dbg2_device { >>> >>> #define ACPI_DBG2_16550_COMPATIBLE 0x0000 >>> #define ACPI_DBG2_16550_SUBSET 0x0001 >>> +#define ACPI_DBG2_16550_32BIT 0x0002 >>> #define ACPI_DBG2_ARM_PL011 0x0003 >>> #define ACPI_DBG2_ARM_SBSA_32BIT 0x000D >>> #define ACPI_DBG2_ARM_SBSA_GENERIC 0x000E >>> -- >> >> This is an ACPICA change and it first needs to be made to the upstream >> ACPICA code base. >> >> Thanks, >> Rafael