Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763660AbdLSOjY (ORCPT ); Tue, 19 Dec 2017 09:39:24 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:20434 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752296AbdLSOjU (ORCPT ); Tue, 19 Dec 2017 09:39:20 -0500 Subject: Re: [PATCH V2 3/9] ARM: stm32: prepare stm32 family to welcome armv7 architecture To: Arnd Bergmann , Ludovic Barre CC: Russell King , Rob Herring , Linus Walleij , Maxime Coquelin , Gerald Baeza , Linux ARM , Linux Kernel Mailing List , DTML References: <1513610272-7824-1-git-send-email-ludovic.Barre@st.com> <1513610272-7824-4-git-send-email-ludovic.Barre@st.com> From: Alexandre Torgue Message-ID: <8092d8f9-c097-136f-4f6f-0b7ffea17c91@st.com> Date: Tue, 19 Dec 2017 15:38:38 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.75.127.48] X-ClientProxiedBy: SFHDAG7NODE2.st.com (10.75.127.20) To SFHDAG3NODE2.st.com (10.75.127.8) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-12-19_07:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2450 Lines: 67 On 12/18/2017 09:24 PM, Arnd Bergmann wrote: > On Mon, Dec 18, 2017 at 4:17 PM, Ludovic Barre wrote: >> From: Ludovic Barre >> >> This patch prepares the STM32 machine for the integration of Cortex-A >> based microprocessor (MPU), on top of the existing Cortex-M >> microcontroller family (MCU). Since both MCUs and MPUs are sharing >> common hardware blocks we can keep using ARCH_STM32 flag for most of >> them. If a hardware block is specific to one family we can use either >> ARM_SINGLE_ARMV7M or ARCH_MULTI_V7 flag. >> >> Signed-off-by: Ludovic Barre > > Looks good overall. Two more small comments: > > >> >> +if ARCH_STM32 >> + >> config MACH_STM32F429 >> - bool "STMicrolectronics STM32F429" >> - depends on ARCH_STM32 >> + bool "STMicroelectronics STM32F429" >> + depends on ARM_SINGLE_ARMV7M >> default y > > Instead of the explicit dependency for each board, I'd leave the surrounding > 'if ARM_SINGLE_ARMV7M'. I think you had in v1. > >> diff --git a/arch/arm/mach-stm32/Makefile b/arch/arm/mach-stm32/Makefile >> index bd0b7b5..5940af1 100644 >> --- a/arch/arm/mach-stm32/Makefile >> +++ b/arch/arm/mach-stm32/Makefile >> @@ -1 +1 @@ >> -obj-y += board-dt.o >> +obj-$(CONFIG_ARM_SINGLE_ARMV7M) += board-mcu-dt.o >> diff --git a/arch/arm/mach-stm32/board-dt.c b/arch/arm/mach-stm32/board-mcu-dt.c >> similarity index 100% >> rename from arch/arm/mach-stm32/board-dt.c >> rename to arch/arm/mach-stm32/board-mcu-dt.c > > Why the rename? I don't expect the new machines to have any notable > contents in a board file, if any at all, so just use one file for both. > I see the board-dt.c file refers to armv7m_restart, we can either put > that in an #ifdef, or find a way to make it the default for all armv7-m > platforms that don't provide any other restart method. > Currently "restart" is not functional on stm32 MCU (at least for stm32f746, I will check on others MCU). My fear is if Ludovic made some patches to make "armv7m_restart" the default ".restart" function for all armv7-m platform, he will not be able to test it on stm32 MCU (as it is not currently working). I propose to do it in 2 steps: 1-Keep as you suggest only one board-dt.c file for both (MCU and MPU) and remove ".restart" function. 2-Investigate and send patches around ".restart" for both in an other series. regards Alex > Arnd >