From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934108AbeAKMgy (ORCPT + 1 other); Thu, 11 Jan 2018 07:36:54 -0500 Received: from mail-oi0-f66.google.com ([209.85.218.66]:40536 "EHLO mail-oi0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933184AbeAKMgw (ORCPT ); Thu, 11 Jan 2018 07:36:52 -0500 X-Google-Smtp-Source: ACJfBov9QltNamvz6haGdvPBwBA+bMf9WmHFhXTk1vYoj0JrBz+XrVsD2AJTzAol3cIhZP5lKcfKNHnKoDDTYAcfBtQ= MIME-Version: 1.0 In-Reply-To: <20180102153620.hhrbov2g5torajim@dell> References: <29fa88f883dae4c1f8a3acb2656cbd7c5a539d40.1514180039.git.baolin.wang@linaro.org> <20180102153620.hhrbov2g5torajim@dell> From: Baolin Wang Date: Thu, 11 Jan 2018 20:36:51 +0800 Message-ID: Subject: Re: [PATCH v7 2/2] mfd: syscon: Add hardware spinlock support To: Lee Jones Cc: Arnd Bergmann , Rob Herring , Mark Rutland , Mark Brown , LKML , DTML Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Hi Arnd, On 2 January 2018 at 23:36, Lee Jones wrote: > Arnd, > >> Some system control registers need hardware spinlock to synchronize >> between the multiple subsystems, so we should add hardware spinlock >> support for syscon. >> >> Signed-off-by: Baolin Wang >> Acked-by: Rob Herring > > ... did you sign off on this in the end? > Could you apply this patch if there are no other issue? Thanks. >> --- >> Changes since v6: >> - Treat hwlock id 0 as valid for regmap. >> >> Changes since v5: >> - Fix the case that hwspinlock is not enabled. >> >> Changes since v4: >> - Add one exapmle to show how to add hwlock. >> - Fix the coding style issue. >> >> Changes since v3: >> - Add error handling for of_hwspin_lock_get_id() >> >> Changes since v2: >> - Add acked tag from Rob. >> >> Changes since v1: >> - Remove timeout configuration. >> - Modify the binding file to add hwlocks. >> --- >> Documentation/devicetree/bindings/mfd/syscon.txt | 8 ++++++++ >> drivers/mfd/syscon.c | 19 +++++++++++++++++++ >> 2 files changed, 27 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/mfd/syscon.txt b/Documentation/devicetree/bindings/mfd/syscon.txt >> index 8b92d45..25d9e9c 100644 >> --- a/Documentation/devicetree/bindings/mfd/syscon.txt >> +++ b/Documentation/devicetree/bindings/mfd/syscon.txt >> @@ -16,9 +16,17 @@ Required properties: >> Optional property: >> - reg-io-width: the size (in bytes) of the IO accesses that should be >> performed on the device. >> +- hwlocks: reference to a phandle of a hardware spinlock provider node. >> >> Examples: >> gpr: iomuxc-gpr@20e0000 { >> compatible = "fsl,imx6q-iomuxc-gpr", "syscon"; >> reg = <0x020e0000 0x38>; >> + hwlocks = <&hwlock1 1>; >> +}; >> + >> +hwlock1: hwspinlock@40500000 { >> + ... >> + reg = <0x40500000 0x1000>; >> + #hwlock-cells = <1>; >> }; >> diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c >> index b93fe4c..7eaa40b 100644 >> --- a/drivers/mfd/syscon.c >> +++ b/drivers/mfd/syscon.c >> @@ -13,6 +13,7 @@ >> */ >> >> #include >> +#include >> #include >> #include >> #include >> @@ -87,6 +88,24 @@ static struct syscon *of_syscon_register(struct device_node *np) >> if (ret) >> reg_io_width = 4; >> >> + ret = of_hwspin_lock_get_id(np, 0); >> + if (ret > 0 || (IS_ENABLED(CONFIG_HWSPINLOCK) && ret == 0)) { >> + syscon_config.use_hwlock = true; >> + syscon_config.hwlock_id = ret; >> + syscon_config.hwlock_mode = HWLOCK_IRQSTATE; >> + } else if (ret < 0) { >> + switch (ret) { >> + case -ENOENT: >> + /* Ignore missing hwlock, it's optional. */ >> + break; >> + default: >> + pr_err("Failed to retrieve valid hwlock: %d\n", ret); >> + /* fall-through */ >> + case -EPROBE_DEFER: >> + goto err_regmap; >> + } >> + } >> + >> syscon_config.reg_stride = reg_io_width; >> syscon_config.val_bits = reg_io_width * 8; >> syscon_config.max_register = resource_size(&res) - reg_io_width; > > -- > Lee Jones > Linaro Services Technical Lead > Linaro.org │ Open source software for ARM SoCs > Follow Linaro: Facebook | Twitter | Blog -- Baolin.wang Best Regards