From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3CF1AC4740C for ; Mon, 23 Sep 2019 07:28:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1569420820 for ; Mon, 23 Sep 2019 07:28:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393524AbfIWH2G (ORCPT ); Mon, 23 Sep 2019 03:28:06 -0400 Received: from mail-sz.amlogic.com ([211.162.65.117]:32336 "EHLO mail-sz.amlogic.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393460AbfIWH2F (ORCPT ); Mon, 23 Sep 2019 03:28:05 -0400 Received: from [10.28.18.45] (10.28.18.45) by mail-sz.amlogic.com (10.28.11.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1591.10; Mon, 23 Sep 2019 15:29:00 +0800 Subject: Re: [PATCH 2/3] pinctrl: meson-a1: add pinctrl driver for Meson A1 Soc To: Jerome Brunet CC: Linus Walleij , , Xingyu Chen , Jianxin Pan , Neil Armstrong , Kevin Hilman , Martin Blumenstingl , Carlo Caione , Rob Herring , Hanjie Lin , Mark Rutland , , , References: <1568700442-18540-1-git-send-email-qianggui.song@amlogic.com> <1568700442-18540-3-git-send-email-qianggui.song@amlogic.com> <1jef0f46fj.fsf@starbuckisacylon.baylibre.com> <73dc56bd-d6c5-1de7-e97e-91479a89a29e@amlogic.com> <1j8sqn3tjt.fsf@starbuckisacylon.baylibre.com> <45b97927-c771-808a-b214-509af6c16931@amlogic.com> <1jk1a4b6c8.fsf@starbuckisacylon.baylibre.com> From: Qianggui Song Message-ID: <2c476d5b-2c16-ede0-58c3-d83b286b7d8a@amlogic.com> Date: Mon, 23 Sep 2019 15:29:00 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <1jk1a4b6c8.fsf@starbuckisacylon.baylibre.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.28.18.45] X-ClientProxiedBy: mail-sz.amlogic.com (10.28.11.5) To mail-sz.amlogic.com (10.28.11.5) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/9/20 0:26, Jerome Brunet wrote: > On Wed 18 Sep 2019 at 14:36, Qianggui Song wrote: > >> On 2019/9/17 22:07, Jerome Brunet wrote: >>> >>> On Tue 17 Sep 2019 at 13:51, Qianggui Song wrote: >>>>>> diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c >>>>>> index 8bba9d0..885b89d 100644 >>>>>> --- a/drivers/pinctrl/meson/pinctrl-meson.c >>>>>> +++ b/drivers/pinctrl/meson/pinctrl-meson.c >>>>>> @@ -688,8 +688,12 @@ static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc, >>>>>> >>>>>> pc->reg_ds = meson_map_resource(pc, gpio_np, "ds"); >>>>>> if (IS_ERR(pc->reg_ds)) { >>>>>> - dev_dbg(pc->dev, "ds registers not found - skipping\n"); >>>>>> - pc->reg_ds = NULL; >>>>>> + if (pc->data->reg_layout == A1_LAYOUT) { >>>>>> + pc->reg_ds = pc->reg_pullen; >>>>> >>>>> IMO, this kind of ID based init fixup is not going to scale and will >>>>> lead to something difficult to maintain in the end. >>>>> >>>>> The way the different register sets interract with each other is already >>>>> pretty complex to follow. >>>>> >>>>> You could rework this in 2 different ways: >>>>> #1 - Have the generic function parse all the register sets and have all >>>>> drivers provide a specific (as in gxbb, gxl, axg, etc ...) function to : >>>>> - Verify the expected sets have been provided >>>>> - Make assignement fixup as above if necessary >>>>> >>>>> #2 - Rework the driver to have only one single register region >>>>> I think one of your colleague previously mentionned this was not >>>>> possible. It is still unclear to me why ... >>>>> >>>> Appreciate your advice. I have an idea based on #1, how about providing >>>> only two dt parse function, one is for chips before A1(the old one), >>>> another is for A1 and later chips that share the same layout. Assign >>>> these two functions to their own driver. >>> >>> That's roughly the same thing as your initial proposition with function >>> pointer instead of IDs ... IMO, this would still be a quick fix to >>> address your immediate topic instead of dealing with the driver as >>> whole, which is my concern here. >>> >> For #1. It would be like >> generic_parse_dt() >> { >> 1. parse all register regions (mux gpio pull pull_en ds) >> >> 2. call specific function through function pointer in >> meson_pinctrl_data.(each platform should have AO and EE two >> specific functions for they are not the same) >> { >> do work you mentioned above >> } >> } >> right ? >> If that so, maybe there are a lot of duplicated codes > > Only if you make it so. Providing a callback and duplicating code are > not the same thing > >> for most Socs share the same reg layout. > > That's not really accurate: > > So far they all have the "mux" and "gpio" region but > > gxbb, gxl, axg, meson8 EE: > has: pull, pull-en > remap: non > unsupported: ds > > gxbb, gxl, axg, meson8 AO: > has: pull > remap: pull-en -> pull > unsupported: ds > > g12 and sm1 EE: > has: pull, pull-en, ds > remap: none > > g12 and sm1 AO: > has: ds > remap: pull->gpio, pull_en->gpio > > And now a1 chip remaps "ds" to "pull_en" ... > > As said previouly all this is getting pretty difficult to follow and > maintain. Adding a proper callback for each meson pinctrl would make the > above explicit in the code ... which helps maintain thing, at least for > a while ... > > Judging by the offsets between those regions, I still think one single > region would make things a whole lot simpler. If it is not possible to > map it with one single region, could you tell us why ? What non-pinctrl > related device do we have there ? >Here I mean duplicated is that m8/m8b/gxl/gxbb/axg use the same layout, while g12a/b/sm1 are the same, so don't need to implement every Socs parser functions just as I said below AXG type for m8/m8b/gxl/gxbb/axg, g12a type for g12a/b/sm1, the last one is for a1. three types functions (with ao and ee) can cover all platform. But I still consider that providing an extra meson_a1_pasert_dt like function for a1 or later is more simpler. The reason why we can not use one single region for previous Socs, it' that there is non-pinctrl related device for some Socs region. Take an example for g12a: #define PREG_PAD_GPIO0_EN_N (0xff634400 + (0x010 << 2)) #define PREG_PAD_GPIO0_O (0xff634400 + (0x011 << 2)) #define PREG_PAD_GPIO0_I (0xff634400 + (0x012 << 2)) ...continue region... #define PAD_PULL_UP_EN_REG5 (0xff634400 + (0x04d << 2)) ... ETH/NAND/VPU/TIMER... a lot of no-pinctrl registers #define PERIPHS_PIN_MUX_0 (0xff634400 + (0x0b0 << 2)) ...continue region... #define PERIPHS_PIN_MUX_F (0xff634400 + (0x0bf << 2)) ...no use region... #define EFUSE_CFG_LOCK (0xff634400 + (0x0c0 << 2)) ...other EFUSE relative registers... ...no use region... #define PAD_DS_REG0A (0xff634400 + (0x0d0 << 2)) ...continue region for all ds... #define PAD_DS_REG5A (0xff634400 + (0x0d6 << 2)) So from the above we can see there are lots of other registers between gpio and ds register.When map gpio to ds region, they will bury a lot of other registers. >> So I guess five specific functions are >> enough: AXG and before(ao,ee), G12A(ao,ee) and A1(will place them in >> pinctrl_meson.c). Since m8 to AXG are the same register layout for both >> ee and ao, G12A with new feature ds and new ao register layout. >> >> Or I misunderstood the #1 ? >>>>>> + } else { >>>>>> + dev_dbg(pc->dev, "ds registers not found - skipping\n"); >>>>>> + pc->reg_ds = NULL; >>>>>> + } >>>>>> } >>>>>> >>>>>> return 0; >>>>>> diff --git a/drivers/pinctrl/meson/pinctrl-meson.h b/drivers/pinctrl/meson/pinctrl-meson.h >>>>>> index c696f32..3d0c58d 100644 >>>>>> --- a/drivers/pinctrl/meson/pinctrl-meson.h >>>>>> +++ b/drivers/pinctrl/meson/pinctrl-meson.h >>>>>> @@ -80,6 +80,14 @@ enum meson_pinconf_drv { >>>>>> }; >>>>>> >>>>>> /** >>>>>> + * enum meson_reg_layout - identify two types of reg layout >>>>>> + */ >>>>>> +enum meson_reg_layout { >>>>>> + LEGACY_LAYOUT, >>>>>> + A1_LAYOUT, >>>>>> +}; >>>>>> + >>>>>> +/** >>>>>> * struct meson bank >>>>>> * >>>>>> * @name: bank name >>>>>> @@ -114,6 +122,7 @@ struct meson_pinctrl_data { >>>>>> unsigned int num_banks; >>>>>> const struct pinmux_ops *pmx_ops; >>>>>> void *pmx_data; >>>>>> + unsigned int reg_layout; >>>>>> }; >>>>>> >>>>>> struct meson_pinctrl { >>>>> >>>>> . >>>>> >>> >>> . >>> > > . >