From patchwork Thu Dec 4 15:33:21 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 5438411 X-Patchwork-Delegate: geert@linux-m68k.org Return-Path: X-Original-To: patchwork-linux-sh@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 873EF9F1D4 for ; Thu, 4 Dec 2014 15:33:41 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 67EEE2025A for ; Thu, 4 Dec 2014 15:33:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E12220253 for ; Thu, 4 Dec 2014 15:33:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754245AbaLDPdi (ORCPT ); Thu, 4 Dec 2014 10:33:38 -0500 Received: from albert.telenet-ops.be ([195.130.137.90]:55577 "EHLO albert.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751265AbaLDPdh (ORCPT ); Thu, 4 Dec 2014 10:33:37 -0500 Received: from ayla.of.borg ([84.193.93.87]) by albert.telenet-ops.be with bizsmtp id PTZX1p00K1t5w8s06TZXAu; Thu, 04 Dec 2014 16:33:36 +0100 Received: from ramsan.of.borg ([192.168.97.29] helo=ramsan) by ayla.of.borg with esmtp (Exim 4.82) (envelope-from ) id 1XwYPL-0000u5-66; Thu, 04 Dec 2014 16:33:31 +0100 Received: from geert by ramsan with local (Exim 4.82) (envelope-from ) id 1XwYPL-0000AI-MJ; Thu, 04 Dec 2014 16:33:31 +0100 From: Geert Uytterhoeven To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse Cc: Simon Horman , Arnd Bergmann , Guenter Roeck , linux-pm@vger.kernel.org, linux-sh@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v2] power: reset: Add reset driver for R-Mobile platforms Date: Thu, 4 Dec 2014 16:33:21 +0100 Message-Id: <1417707201-589-1-git-send-email-geert+renesas@glider.be> X-Mailer: git-send-email 1.9.1 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add a reset driver for Renesas R-Mobile and SH-Mobile SoCs. It registers a restart handler to trigger a soft power-on reset through the R-Mobile System Controller. The priority of this restart handler is 192, to allow a watchdog driver to use priority 128. Note that we do not use syscon-reboot, as the HPB (Peripheral Bus Bridge) semaphore should be acquired on systems where both the ARM and SH core are in use. The driver can be extended later to support this, when needed. Signed-off-by: Geert Uytterhoeven Reviewed-by: Guenter Roeck --- Tested on R-Mobile A1 (r8a7740) and SH-Mobile AG5 (sh73a0). This can be considered v2 of "[PATCH 1/4] ARM: shmobile: R-Mobile: Add SYSC restart handler" (http://www.spinics.net/lists/arm-kernel/msg383402.html). Changes: - Move to a standalone driver under drivers/power/reset that can be modular, - Use register_restart_handler() instead of setting arm_pm_restart, --- drivers/power/reset/Kconfig | 6 +++ drivers/power/reset/Makefile | 1 + drivers/power/reset/rmobile-reset.c | 93 +++++++++++++++++++++++++++++++++++++ 3 files changed, 100 insertions(+) create mode 100644 drivers/power/reset/rmobile-reset.c diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 028e765045196f89..d743145e0001f466 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -159,5 +159,11 @@ config POWER_RESET_SYSCON help Reboot support for generic SYSCON mapped register reset. +config POWER_RESET_RMOBILE + tristate "Renesas R-Mobile reset driver" + depends on ARCH_RMOBILE || COMPILE_TEST + help + Reboot support for Renesas R-Mobile and SH-Mobile SoCs. + endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 1d4804d6b3237c1c..1631652009acc32d 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -18,3 +18,4 @@ obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o +obj-$(CONFIG_POWER_RESET_RMOBILE) += rmobile-reset.o diff --git a/drivers/power/reset/rmobile-reset.c b/drivers/power/reset/rmobile-reset.c new file mode 100644 index 0000000000000000..ff3bbcfd03d1e7b4 --- /dev/null +++ b/drivers/power/reset/rmobile-reset.c @@ -0,0 +1,93 @@ +/* + * Renesas R-Mobile Reset Driver + * + * Copyright (C) 2014 Glider bvba + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include +#include +#include +#include +#include +#include +#include + + +/* SYSC Register Bank 2 */ +#define RESCNT2 0x20 /* Reset Control Register 2 */ + +/* Reset Control Register 2 */ +#define RESCNT2_PRES 0x80000000 /* Soft power-on reset */ + + +static void __iomem *sysc_base2; + +static int rmobile_reset_handler(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + pr_debug("%s %lu\n", __func__, mode); + + /* Let's assume we have acquired the HPB semaphore */ + writel(RESCNT2_PRES, sysc_base2 + RESCNT2); + + return NOTIFY_DONE; +} + +static struct notifier_block rmobile_reset_nb = { + .notifier_call = rmobile_reset_handler, + .priority = 192, +}; + +static int rmobile_reset_probe(struct platform_device *pdev) +{ + int error; + + sysc_base2 = of_iomap(pdev->dev.of_node, 1); + if (!sysc_base2) + return -ENODEV; + + error = register_restart_handler(&rmobile_reset_nb); + if (error) { + dev_err(&pdev->dev, + "cannot register restart handler (err=%d)\n", error); + goto fail_unmap; + } + + return 0; + +fail_unmap: + iounmap(sysc_base2); + return error; +} + +static int rmobile_reset_remove(struct platform_device *pdev) +{ + unregister_restart_handler(&rmobile_reset_nb); + iounmap(sysc_base2); + return 0; +} + +static const struct of_device_id rmobile_reset_of_match[] = { + { .compatible = "renesas,sysc-rmobile", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rmobile_reset_of_match); + +static struct platform_driver rmobile_reset_driver = { + .probe = rmobile_reset_probe, + .remove = rmobile_reset_remove, + .driver = { + .name = "rmobile_reset", + .of_match_table = rmobile_reset_of_match, + }, +}; + +module_platform_driver(rmobile_reset_driver); + +MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver"); +MODULE_AUTHOR("Geert Uytterhoeven "); +MODULE_LICENSE("GPL v2");