From: Antony Pavlov <antonynpavlov@gmail.com>
To: Jan Luebbe <jluebbe@debian.org>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH] watchdog: add davinci watchdog driver
Date: Thu, 23 Apr 2015 08:53:02 +0300 [thread overview]
Message-ID: <20150423085302.0d40ec8ecb8f6ab1169262bb@gmail.com> (raw)
In-Reply-To: <1429700122-31522-1-git-send-email-jluebbe@debian.org>
On Wed, 22 Apr 2015 12:55:22 +0200
Jan Luebbe <jluebbe@debian.org> wrote:
Can we use this driver for davinci's reset_cpu() reimplementation?
> This driver is based on the Linux driver (v4.0).
>
> Signed-off-by: Jan Luebbe <jluebbe@debian.org>
> ---
> drivers/watchdog/Kconfig | 6 ++
> drivers/watchdog/Makefile | 1 +
> drivers/watchdog/davinci_wdt.c | 172 +++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 179 insertions(+)
> create mode 100644 drivers/watchdog/davinci_wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 7f7b02e..582c615 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -10,6 +10,12 @@ menuconfig WATCHDOG
>
> if WATCHDOG
>
> +config WATCHDOG_DAVINCI
> + bool "TI Davinci"
> + depends on ARCH_DAVINCI
> + help
> + Add support for watchdog on the TI Davinci SoC.
> +
> config WATCHDOG_MXS28
> bool "i.MX28"
> depends on ARCH_IMX28
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 865fc47..1e63c49 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -1,4 +1,5 @@
> obj-$(CONFIG_WATCHDOG) += wd_core.o
> +obj-$(CONFIG_WATCHDOG_DAVINCI) += davinci_wdt.o
> obj-$(CONFIG_WATCHDOG_MXS28) += im28wd.o
> obj-$(CONFIG_WATCHDOG_JZ4740) += jz4740.o
> obj-$(CONFIG_WATCHDOG_IMX_RESET_SOURCE) += imxwd.o
> diff --git a/drivers/watchdog/davinci_wdt.c b/drivers/watchdog/davinci_wdt.c
> new file mode 100644
> index 0000000..17bceb8
> --- /dev/null
> +++ b/drivers/watchdog/davinci_wdt.c
> @@ -0,0 +1,172 @@
> +/*
> + * drivers/char/watchdog/davinci_wdt.c
> + *
> + * Watchdog driver for DaVinci DM644x/DM646x processors
> + *
> + * Copyright (C) 2006-2013 Texas Instruments.
> + * Copyright (C) 2015 Jan Luebbe <jluebbe@debian.org>
> + *
> + * 2007 (c) MontaVista Software, Inc. This file is licensed under
> + * the terms of the GNU General Public License version 2. This program
> + * is licensed "as is" without any warranty of any kind, whether express
> + * or implied.
> + */
> +
> +#include <common.h>
> +#include <init.h>
> +#include <io.h>
> +#include <of.h>
> +#include <errno.h>
> +#include <malloc.h>
> +#include <watchdog.h>
> +
> +#include <linux/clk.h>
> +
> +/* Timer register set definition */
> +#define PID12 (0x0)
> +#define EMUMGT (0x4)
> +#define TIM12 (0x10)
> +#define TIM34 (0x14)
> +#define PRD12 (0x18)
> +#define PRD34 (0x1C)
> +#define TCR (0x20)
> +#define TGCR (0x24)
> +#define WDTCR (0x28)
> +
> +/* TCR bit definitions */
> +#define ENAMODE12_DISABLED (0 << 6)
> +#define ENAMODE12_ONESHOT (1 << 6)
> +#define ENAMODE12_PERIODIC (2 << 6)
> +
> +/* TGCR bit definitions */
> +#define TIM12RS_UNRESET (1 << 0)
> +#define TIM34RS_UNRESET (1 << 1)
> +#define TIMMODE_64BIT_WDOG (2 << 2)
> +
> +/* WDTCR bit definitions */
> +#define WDEN (1 << 14)
> +#define WDFLAG (1 << 15)
> +#define WDKEY_SEQ0 (0xa5c6 << 16)
> +#define WDKEY_SEQ1 (0xda7e << 16)
> +
> +/*
> + * struct to hold data for each WDT device
> + * @wd - hold watchdog device as is in WDT core
> + * @base - base io address of WD device
> + * @clk - source clock of WDT
> + * @timeout - previously configured timeout
> + */
> +struct davinci_wdt {
> + struct watchdog wd;
> + void __iomem *base;
> + struct clk *clk;
> + unsigned timeout;
> +};
> +
> +#define to_davinci_wdt(h) container_of(h, struct davinci_wdt, wd)
> +
> +static int davinci_wdt_start(struct watchdog *wd)
> +{
> + u32 tgcr;
> + u32 timer_margin;
> + unsigned long wdt_freq;
> + struct davinci_wdt *davinci_wdt = to_davinci_wdt(wd);
> +
> + wdt_freq = clk_get_rate(davinci_wdt->clk);
> +
> + /* disable, internal clock source */
> + iowrite32(0, davinci_wdt->base + TCR);
> + /* reset timer, set mode to 64-bit watchdog, and unreset */
> + iowrite32(0, davinci_wdt->base + TGCR);
> + tgcr = TIMMODE_64BIT_WDOG | TIM12RS_UNRESET | TIM34RS_UNRESET;
> + iowrite32(tgcr, davinci_wdt->base + TGCR);
> + /* clear counter regs */
> + iowrite32(0, davinci_wdt->base + TIM12);
> + iowrite32(0, davinci_wdt->base + TIM34);
> + /* set timeout period */
> + timer_margin = (((u64)davinci_wdt->timeout * wdt_freq) & 0xffffffff);
> + iowrite32(timer_margin, davinci_wdt->base + PRD12);
> + timer_margin = (((u64)davinci_wdt->timeout * wdt_freq) >> 32);
> + iowrite32(timer_margin, davinci_wdt->base + PRD34);
> + /* enable run continuously */
> + iowrite32(ENAMODE12_PERIODIC, davinci_wdt->base + TCR);
> + /* Once the WDT is in pre-active state write to
> + * TIM12, TIM34, PRD12, PRD34, TCR, TGCR, WDTCR are
> + * write protected (except for the WDKEY field)
> + */
> + /* put watchdog in pre-active state */
> + iowrite32(WDKEY_SEQ0 | WDEN, davinci_wdt->base + WDTCR);
> + /* put watchdog in active state */
> + iowrite32(WDKEY_SEQ1 | WDEN, davinci_wdt->base + WDTCR);
> + return 0;
> +}
> +
> +static int davinci_wdt_ping(struct watchdog *wd)
> +{
> + struct davinci_wdt *davinci_wdt = to_davinci_wdt(wd);
> +
> + /* put watchdog in service state */
> + iowrite32(WDKEY_SEQ0, davinci_wdt->base + WDTCR);
> + /* put watchdog in active state */
> + iowrite32(WDKEY_SEQ1, davinci_wdt->base + WDTCR);
> + return 0;
> +}
> +
> +static int davinci_wdt_set_timeout(struct watchdog *wd, unsigned timeout)
> +{
> + struct davinci_wdt *davinci_wdt = to_davinci_wdt(wd);
> +
> + if (!davinci_wdt->timeout) {
> + davinci_wdt->timeout = timeout;
> + davinci_wdt_start(wd);
> + } else {
> + davinci_wdt_ping(wd);
> + if (davinci_wdt->timeout != timeout)
> + pr_warn("watchdog timeout can not be changed (currently %d)\n",
> + davinci_wdt->timeout);
> + }
> +
> + return 0;
> +}
> +
> +static int davinci_wdt_probe(struct device_d *dev)
> +{
> + int ret = 0;
> + struct davinci_wdt *davinci_wdt;
> +
> + davinci_wdt = xzalloc(sizeof(*davinci_wdt));
> +
> + davinci_wdt->base = dev_request_mem_region(dev, 0);
> + if (!davinci_wdt->base)
> + return -ENODEV;
> +
> + davinci_wdt->clk = clk_get(dev, NULL);
> + if (WARN_ON(IS_ERR(davinci_wdt->clk)))
> + return PTR_ERR(davinci_wdt->clk);
> +
> + clk_enable(davinci_wdt->clk);
> +
> + davinci_wdt->wd.set_timeout = davinci_wdt_set_timeout;
> +
> + ret = watchdog_register(&davinci_wdt->wd);
> + if (ret < 0)
> + dev_err(dev, "cannot register watchdog device\n");
> +
> + return ret;
> +}
> +
> +static __maybe_unused struct of_device_id davinci_wdt_of_match[] = {
> + { .compatible = "ti,davinci-wdt", },
> + {},
> +};
> +
> +static struct driver_d platform_wdt_driver = {
> + .name = "davinci-wdt",
> + .of_compatible = DRV_OF_COMPAT(davinci_wdt_of_match),
> + .probe = davinci_wdt_probe,
> +};
> +device_platform_driver(platform_wdt_driver);
> +
> +MODULE_AUTHOR("Texas Instruments");
> +MODULE_DESCRIPTION("DaVinci Watchdog Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.1.4
>
>
> _______________________________________________
> barebox mailing list
> barebox@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/barebox
--
--
Best regards,
Antony Pavlov
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next prev parent reply other threads:[~2015-04-23 5:48 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-22 10:55 Jan Luebbe
2015-04-22 15:53 ` Uwe Kleine-König
2015-04-23 5:53 ` Antony Pavlov [this message]
2015-05-30 13:03 Jan Luebbe
2015-06-01 12:10 ` Sascha Hauer
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