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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ED2B6C2D0B1 for ; Tue, 10 Dec 2019 05:49:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A5D242077B for ; Tue, 10 Dec 2019 05:49:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726563AbfLJFtU (ORCPT ); Tue, 10 Dec 2019 00:49:20 -0500 Received: from mail-sz.amlogic.com ([211.162.65.117]:50171 "EHLO mail-sz.amlogic.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726573AbfLJFtU (ORCPT ); Tue, 10 Dec 2019 00:49:20 -0500 Received: from [10.28.19.135] (10.28.19.135) by mail-sz.amlogic.com (10.28.11.5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1591.10; Tue, 10 Dec 2019 13:49:42 +0800 Subject: Re: [PATCH v4 2/2] watchdog: add meson secure watchdog driver To: Guenter Roeck , Wim Van Sebroeck , Kevin Hilman , Neil Armstrong , Rob Herring CC: Qianggui Song , , Jianxin Pan , , Jian Hu , , , Jerome Brunet References: <1574685218-31164-1-git-send-email-xingyu.chen@amlogic.com> <1574685218-31164-3-git-send-email-xingyu.chen@amlogic.com> <53661e11-b5b2-b2e8-47b6-9b357beff375@roeck-us.net> From: Xingyu Chen Message-ID: <05503ac6-c43b-0dcd-03b6-6fc8d1545f52@amlogic.com> Date: Tue, 10 Dec 2019 13:49:42 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.1 MIME-Version: 1.0 In-Reply-To: <53661e11-b5b2-b2e8-47b6-9b357beff375@roeck-us.net> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-GB X-Originating-IP: [10.28.19.135] X-ClientProxiedBy: mail-sz.amlogic.com (10.28.11.5) To mail-sz.amlogic.com (10.28.11.5) Sender: linux-watchdog-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org Hi, Guenter On 2019/12/9 22:44, Guenter Roeck wrote: > On 11/25/19 4:33 AM, Xingyu Chen wrote: >> The watchdog controller on the Meson-A/C series SoCs is moved to secure >> world, watchdog operation needs to be done in secure EL3 mode via ATF, >> Non-secure world can call SMC instruction to trap to AFT for watchdog >> operation. >> >> Signed-off-by: Xingyu Chen >> --- >>   drivers/watchdog/Kconfig         |  16 +++ >>   drivers/watchdog/Makefile        |   1 + >>   drivers/watchdog/meson_sec_wdt.c | 207 >> +++++++++++++++++++++++++++++++++++++++ >>   3 files changed, 224 insertions(+) >>   create mode 100644 drivers/watchdog/meson_sec_wdt.c >> >> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig >> index 58e7c10..e305fba 100644 >> --- a/drivers/watchdog/Kconfig >> +++ b/drivers/watchdog/Kconfig >> @@ -826,6 +826,22 @@ config MESON_GXBB_WATCHDOG >>         To compile this driver as a module, choose M here: the >>         module will be called meson_gxbb_wdt. >>   +config MESON_SEC_WATCHDOG >> +    tristate "Amlogic Meson Secure watchdog support" >> +    depends on MESON_SM >> +    select WATCHDOG_CORE >> +    help >> +      The watchdog controller on the Meson-A/C series SoCs is moved to >> +      secure world, watchdog operation needs to be done in secure EL3 >> +      mode via ATF, non-secure world can call SMC instruction to trap >> +      to ATF for the watchdog operation. >> + >> +      Say Y here if watchdog controller on Meson SoCs is located in >> +      secure world. >> + >> +      To compile this driver as a module, choose M here: the >> +      module will be called meson_sec_wdt. >> + >>   config MESON_WATCHDOG >>       tristate "Amlogic Meson SoCs watchdog support" >>       depends on ARCH_MESON || COMPILE_TEST >> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile >> index 2ee352b..5e6b73d 100644 >> --- a/drivers/watchdog/Makefile >> +++ b/drivers/watchdog/Makefile >> @@ -78,6 +78,7 @@ obj-$(CONFIG_QCOM_WDT) += qcom-wdt.o >>   obj-$(CONFIG_BCM_KONA_WDT) += bcm_kona_wdt.o >>   obj-$(CONFIG_TEGRA_WATCHDOG) += tegra_wdt.o >>   obj-$(CONFIG_MESON_GXBB_WATCHDOG) += meson_gxbb_wdt.o >> +obj-$(CONFIG_MESON_SEC_WATCHDOG) += meson_sec_wdt.o >>   obj-$(CONFIG_MESON_WATCHDOG) += meson_wdt.o >>   obj-$(CONFIG_MEDIATEK_WATCHDOG) += mtk_wdt.o >>   obj-$(CONFIG_DIGICOLOR_WATCHDOG) += digicolor_wdt.o >> diff --git a/drivers/watchdog/meson_sec_wdt.c >> b/drivers/watchdog/meson_sec_wdt.c >> new file mode 100644 >> index 00000000..c022d6d >> --- /dev/null >> +++ b/drivers/watchdog/meson_sec_wdt.c >> @@ -0,0 +1,207 @@ >> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT) >> +/* >> + * Copyright (c) 2019 Amlogic, Inc. All rights reserved. >> + * Author: Xingyu Chen >> + * >> + */ >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> +#include >> + >> +#define MESON_SIP_WDT_DISABLE        0x1 >> +#define MESON_SIP_WDT_ENABLE        0x2 >> +#define MESON_SIP_WDT_PING        0x3 >> +#define MESON_SIP_WDT_INIT        0x4 >> +#define MESON_SIP_WDT_RESETNOW        0x5 >> +#define MESON_SIP_WDT_SETTIMEOUT    0x6 >> +#define MESON_SIP_WDT_GETTIMELEFT    0x7 >> + >> +#define DEFAULT_TIMEOUT            30 /* seconds */ >> + >> +/* >> + * Watchdog timer tick is set to 1ms in secfw side, and tick count is >> + * stored in the bit[16-31] of WATCHDOG_CNT register, so the maximum >> + * timeout value is 0xffff ms. >> + */ >> +#define MAX_TIMEOUT_MS            0xFFFF >> +#define DRV_NAME            "meson-sec-wdt" >> + >> +static struct platform_device *platform_device; >> +struct meson_sec_wdt { >> +    struct watchdog_device wdt_dev; >> +    struct meson_sm_firmware *fw; >> +}; >> + >> +static int meson_sec_wdt_start(struct watchdog_device *wdt_dev) >> +{ >> +    struct meson_sec_wdt *data = watchdog_get_drvdata(wdt_dev); >> + >> +    return meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, NULL, >> +                 MESON_SIP_WDT_ENABLE, 0, 0, 0, 0); >> +} >> + >> +static int meson_sec_wdt_stop(struct watchdog_device *wdt_dev) >> +{ >> +    struct meson_sec_wdt *data = watchdog_get_drvdata(wdt_dev); >> + >> +    return meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, NULL, >> +                 MESON_SIP_WDT_DISABLE, 0, 0, 0, 0); >> +} >> + >> +static int meson_sec_wdt_ping(struct watchdog_device *wdt_dev) >> +{ >> +    struct meson_sec_wdt *data = watchdog_get_drvdata(wdt_dev); >> + >> +    return meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, NULL, >> +                 MESON_SIP_WDT_PING, 0, 0, 0, 0); >> +} >> + >> +static int meson_sec_wdt_set_timeout(struct watchdog_device *wdt_dev, >> +                     unsigned int timeout) >> +{ >> +    struct meson_sec_wdt *data = watchdog_get_drvdata(wdt_dev); >> + >> +    wdt_dev->timeout = timeout; >> + >> +    return meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, NULL, >> +                 MESON_SIP_WDT_SETTIMEOUT, >> +                 wdt_dev->timeout * 1000, 0, 0, 0); >> +} >> + >> +static unsigned int meson_sec_wdt_get_timeleft(struct >> watchdog_device *wdt_dev) >> +{ >> +    int ret; >> +    unsigned int timeleft; >> +    struct meson_sec_wdt *data = watchdog_get_drvdata(wdt_dev); >> + >> +    ret = meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, &timeleft, >> +                MESON_SIP_WDT_GETTIMELEFT, 0, 0, 0, 0); >> + >> +    if (ret) >> +        return 0; >> + >> +    return timeleft; >> +} >> + >> +static const struct watchdog_ops meson_sec_wdt_ops = { >> +    .start = meson_sec_wdt_start, >> +    .stop = meson_sec_wdt_stop, >> +    .ping = meson_sec_wdt_ping, >> +    .set_timeout = meson_sec_wdt_set_timeout, >> +    .get_timeleft = meson_sec_wdt_get_timeleft, >> +}; >> + >> +static const struct watchdog_info meson_sec_wdt_info = { >> +    .identity = "Meson Secure Watchdog Timer", >> +    .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | >> WDIOF_MAGICCLOSE, >> +}; >> + >> +static int __maybe_unused meson_sec_wdt_resume(struct device *dev) >> +{ >> +    struct meson_sec_wdt *data = dev_get_drvdata(dev); >> + >> +    if (watchdog_active(&data->wdt_dev)) >> +        return meson_sec_wdt_start(&data->wdt_dev); >> + >> +    return 0; >> +} >> + >> +static int __maybe_unused meson_sec_wdt_suspend(struct device *dev) >> +{ >> +    struct meson_sec_wdt *data = dev_get_drvdata(dev); >> + >> +    if (watchdog_active(&data->wdt_dev)) >> +        return meson_sec_wdt_stop(&data->wdt_dev); >> + >> +    return 0; >> +} >> + >> +static const struct dev_pm_ops meson_sec_wdt_pm_ops = { >> +    SET_SYSTEM_SLEEP_PM_OPS(meson_sec_wdt_suspend, >> meson_sec_wdt_resume) >> +}; >> + >> +static int meson_sec_wdt_probe(struct platform_device *pdev) >> +{ >> +    struct device *dev = &pdev->dev; >> +    struct meson_sec_wdt *data; >> +    struct device_node *sm_np; >> +    int ret; >> + >> +    data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); >> +    if (!data) >> +        return -ENOMEM; >> + >> +    sm_np = of_find_compatible_node(NULL, NULL, >> "amlogic,meson-gxbb-sm"); >> +    if (!sm_np) { >> +        dev_err(&pdev->dev, "no secure-monitor node\n"); >> +        return -EINVAL; >> +    } >> + >> +    data->fw = meson_sm_get(sm_np); >> +    of_node_put(sm_np); >> +    if (!data->fw) >> +        return -EPROBE_DEFER; >> + >> +    platform_set_drvdata(pdev, data); >> + >> +    data->wdt_dev.parent = dev; >> +    data->wdt_dev.info = &meson_sec_wdt_info; >> +    data->wdt_dev.ops = &meson_sec_wdt_ops; >> +    data->wdt_dev.max_hw_heartbeat_ms = MAX_TIMEOUT_MS; >> +    data->wdt_dev.min_timeout = 1; >> +    data->wdt_dev.timeout = DEFAULT_TIMEOUT; >> +    watchdog_set_drvdata(&data->wdt_dev, data); >> + >> +    ret = meson_sm_call(data->fw, SM_A1_WATCHDOG_OPS, NULL, >> +                MESON_SIP_WDT_INIT, >> +                data->wdt_dev.timeout * 1000, 0, 0, 0); >> +    if (ret) >> +        return ret; >> + >> +    watchdog_stop_on_reboot(&data->wdt_dev); >> + >> +    return devm_watchdog_register_device(dev, &data->wdt_dev); >> +} >> + >> +static struct platform_driver meson_sec_wdt_driver = { >> +    .probe    = meson_sec_wdt_probe, >> +    .driver = { >> +        .name = DRV_NAME, >> +        .pm = &meson_sec_wdt_pm_ops, >> +    }, >> +}; >> + >> +static int __init meson_sec_wdt_init(void) >> +{ >> +    int ret; >> + >> +    ret = platform_driver_register(&meson_sec_wdt_driver); >> +    if (ret) >> +        return ret; >> + >> +    platform_device = platform_device_register_simple(DRV_NAME, >> +                              -1, NULL, 0); >> +    if (IS_ERR(platform_device)) { >> +        ret = PTR_ERR(platform_device); >> +        platform_driver_unregister(&meson_sec_wdt_driver); >> +    } >> + >> +    return ret; >> +} >> + >> +static void __exit meson_sec_wdt_exit(void) >> +{ >> +    platform_device_unregister(platform_device); >> +    platform_driver_unregister(&meson_sec_wdt_driver); >> +} >> + >> +module_init(meson_sec_wdt_init); >> +module_exit(meson_sec_wdt_exit); >> + > > Driver instantiation is wrong. It tries to instantiate itself as soon > as the module is loaded and then it bails out in the probe funmction. > It should be instantiated either through a devicetree node or through > some platform code, but it should not instantiate itself. If there > is no watchdog node, the driver needs to be instantiated from > drivers/firmware/meson/meson_sm.c. > > Guenter > Thanks for your suggestion. In next version, I will instantiated device and introduce "timeout-sec" property through a dts node. >> +MODULE_AUTHOR("Xingyu Chen "); >> +MODULE_DESCRIPTION("Amlogic Secure Watchdog Timer Driver"); >> +MODULE_LICENSE("Dual MIT/GPL"); >> > > > _______________________________________________ > linux-amlogic mailing list > linux-amlogic@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-amlogic > > . >