From patchwork Mon Jan 12 15:57:25 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Geert Uytterhoeven X-Patchwork-Id: 5611221 Return-Path: X-Original-To: patchwork-linux-pm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 5DCE29F357 for ; Mon, 12 Jan 2015 15:57:39 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5F69F205B8 for ; Mon, 12 Jan 2015 15:57:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6DDE82064D for ; Mon, 12 Jan 2015 15:57:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751608AbbALP5e (ORCPT ); Mon, 12 Jan 2015 10:57:34 -0500 Received: from xavier.telenet-ops.be ([195.130.132.52]:59980 "EHLO xavier.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751214AbbALP5d (ORCPT ); Mon, 12 Jan 2015 10:57:33 -0500 Received: from ayla.of.borg ([84.193.93.87]) by xavier.telenet-ops.be with bizsmtp id f3xU1p0051t5w8s013xUGi; Mon, 12 Jan 2015 16:57:31 +0100 Received: from ramsan.of.borg ([192.168.97.29] helo=ramsan) by ayla.of.borg with esmtp (Exim 4.82) (envelope-from ) id 1YAhMt-0004yN-RY; Mon, 12 Jan 2015 16:57:27 +0100 Received: from geert by ramsan with local (Exim 4.82) (envelope-from ) id 1YAhMx-0001Ro-5s; Mon, 12 Jan 2015 16:57:31 +0100 From: Geert Uytterhoeven To: Sebastian Reichel , Dmitry Eremin-Solenikov , David Woodhouse Cc: Guenter Roeck , linux-pm@vger.kernel.org, linux-sh@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v3] power: reset: Add reset driver for R-Mobile platforms Date: Mon, 12 Jan 2015 16:57:25 +0100 Message-Id: <1421078245-5531-1-git-send-email-geert+renesas@glider.be> X-Mailer: git-send-email 1.9.1 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@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=unavailable 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. As this is controlled by DT, 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). v3: - Add DT priority explanation, - Add Reviewed-by, v2: - 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), - 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");