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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CA1AAC4332F for ; Thu, 22 Dec 2022 14:35:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235856AbiLVOfK (ORCPT ); Thu, 22 Dec 2022 09:35:10 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39210 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235823AbiLVOe5 (ORCPT ); Thu, 22 Dec 2022 09:34:57 -0500 Received: from mx07-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62C572CC9C; Thu, 22 Dec 2022 06:34:54 -0800 (PST) Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2BMED0A2026702; Thu, 22 Dec 2022 15:34:32 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=selector1; bh=67fzNKXCkBzoxXsOTsF9p1AcsrU4OSEoaRnEhq/v5Jk=; b=bDcJQ0x0Z3/kK3cGayQHg9jkb1RZrqRpzT/DnKLH0FDC1iaD7ALHU1r50ewhPeywwbbK 6BG6EgDUpC2xDFF4xrfqXZ5RwK9UbORel4Lcx/PCk1VT8UEfWZ3vvKkkCjqvMIW3nkOl MH901dSAqFm41vXdgb65H/k2aopeIqgC1L0B7Ho9Qzco7kb0u4m9BvhS5v7S4Cd+KuA8 G5bCIQ77H6nYI7sh0NAuodEiXoTxjRDIKrWltCV80lcgJi/IqNzMQw54uZUBLi7iLsQx h4R6+b/zYHzoGw5NKD/vlfrkKa6buKzglzbFgvocrSV1mH3sj5OyYbKnZPy0OjRn+vpO XQ== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3mkc8jffr6-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 22 Dec 2022 15:34:24 +0100 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 08A2C100038; Thu, 22 Dec 2022 15:32:11 +0100 (CET) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 88901229A83; Thu, 22 Dec 2022 15:30:15 +0100 (CET) Received: from [10.201.21.217] (10.201.21.217) by SHFDAG1NODE1.st.com (10.75.129.69) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.13; Thu, 22 Dec 2022 15:30:14 +0100 Message-ID: Date: Thu, 22 Dec 2022 15:30:14 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [RFC PATCH 5/7] bus: stm32_sys_bus: add support for STM32MP15 and STM32MP13 system bus Content-Language: en-US To: Krzysztof Kozlowski , , , , , CC: , , , , , , References: <20221221173055.11719-1-gatien.chevallier@foss.st.com> <20221221173055.11719-6-gatien.chevallier@foss.st.com> From: Gatien CHEVALLIER In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.201.21.217] X-ClientProxiedBy: EQNCAS1NODE4.st.com (10.75.129.82) To SHFDAG1NODE1.st.com (10.75.129.69) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.923,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-12-22_07,2022-12-22_03,2022-06-22_01 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/22/22 11:28, Krzysztof Kozlowski wrote: > On 21/12/2022 18:30, Gatien Chevallier wrote: >> This driver is checking the access rights of the different >> peripherals connected to the system bus. If access is denied, >> the associated device tree node is skipped so the platform bus >> does not probe it. >> >> Signed-off-by: Loic PALLARDY >> Signed-off-by: Gatien Chevallier >> --- >> MAINTAINERS | 6 ++ >> drivers/bus/Kconfig | 9 ++ >> drivers/bus/Makefile | 1 + >> drivers/bus/stm32_sys_bus.c | 180 ++++++++++++++++++++++++++++++++++++ >> 4 files changed, 196 insertions(+) >> create mode 100644 drivers/bus/stm32_sys_bus.c >> >> diff --git a/MAINTAINERS b/MAINTAINERS >> index 886d3f69ee64..768a8272233e 100644 >> --- a/MAINTAINERS >> +++ b/MAINTAINERS >> @@ -19522,6 +19522,12 @@ L: linux-spi@vger.kernel.org >> S: Maintained >> F: drivers/spi/spi-stm32.c >> >> +ST STM32 SYS BUS DRIVER >> +M: Gatien Chevallier >> +S: Maintained >> +F: Documentation/devicetree/bindings/bus/st,sys-bus.yaml >> +F: drivers/bus/stm32_sys_bus.c >> + >> ST STPDDC60 DRIVER >> M: Daniel Nilsson >> L: linux-hwmon@vger.kernel.org >> diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig >> index 7bfe998f3514..638bf5839cb0 100644 >> --- a/drivers/bus/Kconfig >> +++ b/drivers/bus/Kconfig >> @@ -163,6 +163,15 @@ config QCOM_SSC_BLOCK_BUS >> i2c/spi/uart controllers, a hexagon core, and a clock controller >> which provides clocks for the above. >> >> +config STM32_SYS_BUS >> + bool "STM32 System bus controller" >> + depends on ARCH_STM32 > > || COMPILE_TEST Sure, I will add this in V3 > >> + default MACH_STM32MP157 || MACH_STM32MP13 >> + help >> + Say y to enable device access right verification before device probing. >> + If access not granted, device won't be probed and an error message will >> + provide the reason. > > (...) > >> + >> +static int stm32_sys_bus_probe(struct platform_device *pdev) >> +{ >> + struct sys_bus_data *pdata; >> + struct resource *res; >> + void __iomem *mmio; >> + struct stm32_sys_bus_match_data *mdata; >> + struct device_node *np = pdev->dev.of_node; >> + >> + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); >> + if (!pdata) >> + return -ENOMEM; >> + >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + mmio = devm_ioremap_resource(&pdev->dev, res); > > Use helper for these two. Ok, I will use devm_platform_ioremap_resource() > >> + if (IS_ERR(mmio)) >> + return PTR_ERR(mmio); >> + >> + pdata->sys_bus_base = mmio; >> + >> + mdata = (struct stm32_sys_bus_match_data *)of_device_get_match_data(&pdev->dev); > > Why do you need the cast? I do not :) TBH, mdata is not useful at all. Changing to directly assign to pdata->pconf, that is now const there is no reason to modify it. > >> + if (!mdata) > > Can you explain the case when this can actually happen? If it can, you > have bug in ID table. No I cannot as the driver is probed. It is only a sanity check, I can remove it for V3. However the function can return NULL... Would you prefer an explicit check on NULL or a simple removal? > >> + return -EINVAL; >> + >> + pdata->pconf = mdata; >> + pdata->dev = &pdev->dev; >> + >> + platform_set_drvdata(pdev, pdata); >> + >> + stm32_sys_bus_populate(pdata); >> + >> + /* Populate all available nodes */ >> + return of_platform_populate(np, NULL, NULL, &pdev->dev); >> +} >> + >> +static const struct stm32_sys_bus_match_data stm32mp15_sys_bus_data = { >> + .max_entries = STM32MP15_ETZPC_ENTRIES, >> + .sys_bus_get_access = stm32_etzpc_get_access, >> +}; >> + >> +static const struct stm32_sys_bus_match_data stm32mp13_sys_bus_data = { >> + .max_entries = STM32MP13_ETZPC_ENTRIES, >> + .sys_bus_get_access = stm32_etzpc_get_access, > > It's the same as previous, drop. Yes, ops is useless, I will directly call stm32_etzpc_get_access() in V3. > >> +}; >> + >> +static const struct of_device_id stm32_sys_bus_of_match[] = { >> + { .compatible = "st,stm32mp15-sys-bus", .data = &stm32mp15_sys_bus_data }, >> + { .compatible = "st,stm32mp13-sys-bus", .data = &stm32mp13_sys_bus_data }, >> + {} >> +}; >> +MODULE_DEVICE_TABLE(of, stm32_sys_bus_of_match); >> + >> +static struct platform_driver stm32_sys_bus_driver = { >> + .probe = stm32_sys_bus_probe, >> + .driver = { >> + .name = "stm32-sys-bus", >> + .of_match_table = stm32_sys_bus_of_match, >> + }, >> +}; >> + >> +static int __init stm32_sys_bus_init(void) >> +{ >> + return platform_driver_register(&stm32_sys_bus_driver); >> +} >> +arch_initcall(stm32_sys_bus_init); >> + > > Best regards, > Krzysztof > Best regards, Gatien