From patchwork Thu Apr 7 07:17:05 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Claudiu Beznea X-Patchwork-Id: 558670 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 5476CC433FE for ; Thu, 7 Apr 2022 07:16:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241606AbiDGHSP (ORCPT ); Thu, 7 Apr 2022 03:18:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52286 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241678AbiDGHR1 (ORCPT ); Thu, 7 Apr 2022 03:17:27 -0400 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.153.233]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4439E14F127; Thu, 7 Apr 2022 00:15:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1649315723; x=1680851723; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=oQ6NbgVbEuV5G6IspjdoFPFdN0GCADuL/PrOyaUBYtw=; b=zrN7pWpQwQ+eHGDIXUD90OS9LvUoieAvGOo5Y+yzaOrDAqAfNxNk2l+r 7L9o2eF8ZZeIJRXBTmKas3KNZIQ4T6EFkjXbSgVVaXWGmCfukD7g923EQ q+EQ7kLXRVy40g6/uAdT18SklzoRqXiW8Rp+bxdMbZygZ8sMr/a+TWTwV snHS8Vs9PdrbarovdD80kJTnS8yex51vRUYabV++GhsD25yMHAbUgmgbK W1kOLBsRI70o9fyrjzqrou6W0Lqftss84R4xvkvnwy76iYyBs4Lbk0rf2 Ihqu0BDWXrxvW4NMHK4F386URvC6EUoaze5kwy9NVaOFNil19Ff8E6d/m g==; X-IronPort-AV: E=Sophos;i="5.90,241,1643698800"; d="scan'208";a="159679179" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa3.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 07 Apr 2022 00:15:22 -0700 Received: from chn-vm-ex02.mchp-main.com (10.10.87.72) by chn-vm-ex02.mchp-main.com (10.10.87.72) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.17; Thu, 7 Apr 2022 00:15:22 -0700 Received: from localhost.localdomain (10.10.115.15) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server id 15.1.2375.17 via Frontend Transport; Thu, 7 Apr 2022 00:15:19 -0700 From: Claudiu Beznea To: , , , , , , , , CC: , Claudiu Beznea Subject: [PATCH v2 07/10] power: reset: at91-reset: add reset_controller_dev support Date: Thu, 7 Apr 2022 10:17:05 +0300 Message-ID: <20220407071708.3848812-8-claudiu.beznea@microchip.com> X-Mailer: git-send-email 2.33.0 In-Reply-To: <20220407071708.3848812-1-claudiu.beznea@microchip.com> References: <20220407071708.3848812-1-claudiu.beznea@microchip.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org SAMA7G5 reset controller has 5 extra lines that goes to different devices (3 lines to USB PHYs, 1 line to DDR controller, 1 line to DDR PHY controller). These reset lines could be requested by different controller drivers (e.g. USB PHY driver) and these controllers' drivers could assert/deassert these lines when necessary. Thus add support for reset_controller_dev which brings this functionality. Signed-off-by: Claudiu Beznea Reviewed-by: Philipp Zabel --- drivers/power/reset/at91-reset.c | 107 +++++++++++++++++++++++++++++-- 1 file changed, 103 insertions(+), 4 deletions(-) diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c index 1b2aca3f490d..a6f65ac430cd 100644 --- a/drivers/power/reset/at91-reset.c +++ b/drivers/power/reset/at91-reset.c @@ -17,10 +17,13 @@ #include #include #include +#include #include #include +#include + #define AT91_RSTC_CR 0x00 /* Reset Controller Control Register */ #define AT91_RSTC_PROCRST BIT(0) /* Processor Reset */ #define AT91_RSTC_PERRST BIT(2) /* Peripheral Reset */ @@ -65,7 +68,10 @@ enum reset_type { * struct at91_reset - AT91 reset specific data structure * @rstc_base: base address for system reset * @ramc_base: array with base addresses of RAM controllers + * @dev_base: base address for devices reset * @sclk: slow clock + * @rcdev: reset controller device + * @lock: lock for devices reset register access * @nb: reset notifier block * @args: SoC specific system reset arguments * @ramc_lpr: SDRAM Controller Low Power Register @@ -73,12 +79,17 @@ enum reset_type { struct at91_reset { void __iomem *rstc_base; void __iomem *ramc_base[2]; + void __iomem *dev_base; struct clk *sclk; + struct reset_controller_dev rcdev; + spinlock_t lock; struct notifier_block nb; u32 args; u32 ramc_lpr; }; +#define to_at91_reset(r) container_of(r, struct at91_reset, rcdev) + /** * struct at91_reset_data - AT91 reset data * @reset_args: SoC specific system reset arguments @@ -216,6 +227,88 @@ static const struct of_device_id at91_reset_of_match[] = { }; MODULE_DEVICE_TABLE(of, at91_reset_of_match); +static int at91_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct at91_reset *reset = to_at91_reset(rcdev); + u32 val; + + spin_lock(&reset->lock); + val = readl_relaxed(reset->dev_base); + if (assert) + val |= BIT(id); + else + val &= ~BIT(id); + writel_relaxed(val, reset->dev_base); + spin_unlock(&reset->lock); + + return 0; +} + +static int at91_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return at91_reset_update(rcdev, id, true); +} + +static int at91_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return at91_reset_update(rcdev, id, false); +} + +static int at91_reset_dev_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct at91_reset *reset = to_at91_reset(rcdev); + u32 val; + + spin_lock(&reset->lock); + val = readl_relaxed(reset->dev_base); + spin_unlock(&reset->lock); + + return !!(val & BIT(id)); +} + +static const struct reset_control_ops at91_reset_ops = { + .assert = at91_reset_assert, + .deassert = at91_reset_deassert, + .status = at91_reset_dev_status, +}; + +static int at91_reset_of_xlate(struct reset_controller_dev *rcdev, + const struct of_phandle_args *reset_spec) +{ + if (reset_spec->args[0] < SAMA7G5_RESET_USB_PHY1 || + reset_spec->args[0] > SAMA7G5_RESET_USB_PHY3) + return -EINVAL; + + return reset_spec->args[0]; +} + +static int at91_rcdev_init(struct at91_reset *reset, + const struct at91_reset_data *data, + struct platform_device *pdev) +{ + if (!data->n_device_reset) + return 0; + + reset->dev_base = devm_of_iomap(&pdev->dev, pdev->dev.of_node, 1, + NULL); + if (IS_ERR(reset->dev_base)) + return -ENODEV; + + spin_lock_init(&reset->lock); + reset->rcdev.ops = &at91_reset_ops; + reset->rcdev.owner = THIS_MODULE; + reset->rcdev.of_node = pdev->dev.of_node; + reset->rcdev.nr_resets = data->n_device_reset; + reset->rcdev.of_reset_n_cells = 1; + reset->rcdev.of_xlate = at91_reset_of_xlate; + + return devm_reset_controller_register(&pdev->dev, &reset->rcdev); +} + static int __init at91_reset_probe(struct platform_device *pdev) { const struct of_device_id *match; @@ -269,6 +362,10 @@ static int __init at91_reset_probe(struct platform_device *pdev) platform_set_drvdata(pdev, reset); + ret = at91_rcdev_init(reset, data, pdev); + if (ret) + goto disable_clk; + if (of_device_is_compatible(pdev->dev.of_node, "microchip,sam9x60-rstc")) { u32 val = readl(reset->rstc_base + AT91_RSTC_MR); @@ -277,14 +374,16 @@ static int __init at91_reset_probe(struct platform_device *pdev) } ret = register_restart_handler(&reset->nb); - if (ret) { - clk_disable_unprepare(reset->sclk); - return ret; - } + if (ret) + goto disable_clk; at91_reset_status(pdev, reset->rstc_base); return 0; + +disable_clk: + clk_disable_unprepare(reset->sclk); + return ret; } static int __exit at91_reset_remove(struct platform_device *pdev)