diff mbox series

[v2,2/2] watchdog: sama5d4_wdt: addition of sam9x60 compatible watchdog

Message ID 1571648890-15140-2-git-send-email-eugen.hristev@microchip.com (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] dt-bindings: watchdog: sama5d4_wdt: add microchip,sam9x60-wdt compatible | expand

Commit Message

Eugen Hristev Oct. 21, 2019, 9:14 a.m. UTC
From: Eugen Hristev <eugen.hristev@microchip.com>

Add support for SAM9X60 WDT into sama5d4_wdt.
This means that this driver will have a platform data that will
hold differences.
Added definitions of different bits.
The ops functions will differentiate between the two hardware blocks.

Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
---

Hello,

This is a rework of the separate sam9x60 watchdog driver into a single driver
that supports both hardware blocks (sam9x60 and sama5d4)
This was done as suggested on the original patches on the mailing list.

Thanks,
Eugen

 drivers/watchdog/at91sam9_wdt.h |  14 +++++
 drivers/watchdog/sama5d4_wdt.c  | 127 +++++++++++++++++++++++++++++++---------
 2 files changed, 112 insertions(+), 29 deletions(-)

Comments

Guenter Roeck Oct. 29, 2019, 1:28 p.m. UTC | #1
On Mon, Oct 21, 2019 at 09:14:09AM +0000, Eugen.Hristev@microchip.com wrote:
> From: Eugen Hristev <eugen.hristev@microchip.com>
> 
> Add support for SAM9X60 WDT into sama5d4_wdt.
> This means that this driver will have a platform data that will
> hold differences.
> Added definitions of different bits.
> The ops functions will differentiate between the two hardware blocks.
> 
> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
> ---
> 
> Hello,
> 
> This is a rework of the separate sam9x60 watchdog driver into a single driver
> that supports both hardware blocks (sam9x60 and sama5d4)
> This was done as suggested on the original patches on the mailing list.
> 
> Thanks,
> Eugen
> 
>  drivers/watchdog/at91sam9_wdt.h |  14 +++++
>  drivers/watchdog/sama5d4_wdt.c  | 127 +++++++++++++++++++++++++++++++---------
>  2 files changed, 112 insertions(+), 29 deletions(-)
> 
> diff --git a/drivers/watchdog/at91sam9_wdt.h b/drivers/watchdog/at91sam9_wdt.h
> index 390941c..7a053fd 100644
> --- a/drivers/watchdog/at91sam9_wdt.h
> +++ b/drivers/watchdog/at91sam9_wdt.h
> @@ -20,7 +20,10 @@
>  #define AT91_WDT_MR		0x04			/* Watchdog Mode Register */
>  #define		AT91_WDT_WDV		(0xfff << 0)		/* Counter Value */
>  #define			AT91_WDT_SET_WDV(x)	((x) & AT91_WDT_WDV)
> +#define		AT91_SAM9X60_PERIODRST	BIT(4)		/* Period Reset */
> +#define		AT91_SAM9X60_RPTHRST	BIT(5)		/* Minimum Restart Period */
>  #define		AT91_WDT_WDFIEN		(1     << 12)		/* Fault Interrupt Enable */
> +#define		AT91_SAM9X60_WDDIS		BIT(12)		/* Disable */
>  #define		AT91_WDT_WDRSTEN	(1     << 13)		/* Reset Processor */
>  #define		AT91_WDT_WDRPROC	(1     << 14)		/* Timer Restart */
>  #define		AT91_WDT_WDDIS		(1     << 15)		/* Watchdog Disable */
> @@ -33,4 +36,15 @@
>  #define		AT91_WDT_WDUNF		(1 << 0)		/* Watchdog Underflow */
>  #define		AT91_WDT_WDERR		(1 << 1)		/* Watchdog Error */
>  
> +#define AT91_SAM9X60_VR		0x08			/* Watchdog Timer Value Register */
> +
> +#define AT91_SAM9X60_WLR		0x0c
> +#define		AT91_SAM9X60_COUNTER	(0xfff << 0)		/* Watchdog Period Value */
> +#define		AT91_SAM9X60_SET_COUNTER(x)	((x) & AT91_SAM9X60_COUNTER)
> +
> +#define AT91_SAM9X60_IER		0x14			/* Interrupt Enable Register */
> +#define		AT91_SAM9X60_PERINT		BIT(0)		/* Period Interrupt Enable */
> +#define AT91_SAM9X60_IDR		0x18			/* Interrupt Disable Register */
> +#define AT91_SAM9X60_ISR		0x1c			/* Interrupt Status Register */
> +

Those tabs are getting messy, and the mix of BIT() and shift is messy too.
Mind cleaning it up a bit ? Especially, two tabs after #define doesn't really
add value (use two spaces), and use BIT() throughout or not at all.

>  #endif
> diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
> index d193a60..b92afd7 100644
> --- a/drivers/watchdog/sama5d4_wdt.c
> +++ b/drivers/watchdog/sama5d4_wdt.c
> @@ -2,7 +2,7 @@
>  /*
>   * Driver for Atmel SAMA5D4 Watchdog Timer
>   *
> - * Copyright (C) 2015 Atmel Corporation
> + * Copyright (C) 2015-2019 Microchip Technology Inc. and its subsidiaries
>   */
>  
>  #include <linux/delay.h>
> @@ -11,6 +11,7 @@
>  #include <linux/kernel.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
> +#include <linux/of_device.h>
>  #include <linux/of_irq.h>
>  #include <linux/platform_device.h>
>  #include <linux/reboot.h>
> @@ -25,11 +26,18 @@
>  
>  #define WDT_SEC2TICKS(s)	((s) ? (((s) << 8) - 1) : 0)
>  
> +struct sama5d4_wdt_data {
> +	const unsigned int		sam9x60_support;
> +};
> +
>  struct sama5d4_wdt {
> -	struct watchdog_device	wdd;
> -	void __iomem		*reg_base;
> -	u32			mr;
> -	unsigned long		last_ping;
> +	struct watchdog_device		wdd;
> +	const struct sama5d4_wdt_data	*data;
> +	void __iomem			*reg_base;
> +	u32				mr;
> +	u32				ir;
> +	unsigned long			last_ping;
> +	unsigned int			need_irq:1;

This can be a bool. Making it a bit just adds complexity to the code.

>  };
>  
>  static int wdt_timeout;
> @@ -78,7 +86,12 @@ static int sama5d4_wdt_start(struct watchdog_device *wdd)
>  {
>  	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>  
> -	wdt->mr &= ~AT91_WDT_WDDIS;
> +	if (wdt->data->sam9x60_support) {
> +		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IER);
> +		wdt->mr &= ~AT91_SAM9X60_WDDIS;
> +	} else {
> +		wdt->mr &= ~AT91_WDT_WDDIS;
> +	}
>  	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
>  
>  	return 0;
> @@ -88,7 +101,12 @@ static int sama5d4_wdt_stop(struct watchdog_device *wdd)
>  {
>  	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>  
> -	wdt->mr |= AT91_WDT_WDDIS;
> +	if (wdt->data->sam9x60_support) {
> +		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IDR);
> +		wdt->mr |= AT91_SAM9X60_WDDIS;
> +	} else {
> +		wdt->mr |= AT91_WDT_WDDIS;
> +	}
>  	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
>  
>  	return 0;
> @@ -109,6 +127,14 @@ static int sama5d4_wdt_set_timeout(struct watchdog_device *wdd,
>  	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>  	u32 value = WDT_SEC2TICKS(timeout);
>  
> +	if (wdt->data->sam9x60_support) {
> +		wdt_write(wdt, AT91_SAM9X60_WLR,
> +			  AT91_SAM9X60_SET_COUNTER(value));
> +
> +		wdd->timeout = timeout;
> +		return 0;
> +	}
> +
>  	wdt->mr &= ~AT91_WDT_WDV;
>  	wdt->mr |= AT91_WDT_SET_WDV(value);
>  
> @@ -143,8 +169,14 @@ static const struct watchdog_ops sama5d4_wdt_ops = {
>  static irqreturn_t sama5d4_wdt_irq_handler(int irq, void *dev_id)
>  {
>  	struct sama5d4_wdt *wdt = platform_get_drvdata(dev_id);
> +	u32 reg;
>  
> -	if (wdt_read(wdt, AT91_WDT_SR)) {
> +	if (wdt->data->sam9x60_support)
> +		reg = wdt_read(wdt, AT91_SAM9X60_ISR);
> +	else
> +		reg = wdt_read(wdt, AT91_WDT_SR);
> +
> +	if (reg) {
>  		pr_crit("Atmel Watchdog Software Reset\n");
>  		emergency_restart();
>  		pr_crit("Reboot didn't succeed\n");
> @@ -157,13 +189,14 @@ static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
>  {
>  	const char *tmp;
>  
> -	wdt->mr = AT91_WDT_WDDIS;
> +	if (wdt->data->sam9x60_support)
> +		wdt->mr = AT91_SAM9X60_WDDIS;
> +	else
> +		wdt->mr = AT91_WDT_WDDIS;
>  
>  	if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
>  	    !strcmp(tmp, "software"))
> -		wdt->mr |= AT91_WDT_WDFIEN;
> -	else
> -		wdt->mr |= AT91_WDT_WDRSTEN;
> +		wdt->need_irq = 1;
>  
>  	if (of_property_read_bool(np, "atmel,idle-halt"))
>  		wdt->mr |= AT91_WDT_WDIDLEHLT;
> @@ -176,21 +209,46 @@ static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
>  
>  static int sama5d4_wdt_init(struct sama5d4_wdt *wdt)
>  {
> -	u32 reg;
> +	u32 reg, val;
> +
> +	val = WDT_SEC2TICKS(WDT_DEFAULT_TIMEOUT);
>  	/*
>  	 * When booting and resuming, the bootloader may have changed the
>  	 * watchdog configuration.
>  	 * If the watchdog is already running, we can safely update it.
>  	 * Else, we have to disable it properly.
>  	 */
> -	if (wdt_enabled) {
> -		wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
> -	} else {
> +	if (!wdt_enabled) {
>  		reg = wdt_read(wdt, AT91_WDT_MR);
> -		if (!(reg & AT91_WDT_WDDIS))
> +		if (wdt->data->sam9x60_support && (!(reg & AT91_SAM9X60_WDDIS)))
> +			wdt_write_nosleep(wdt, AT91_WDT_MR,
> +					  reg | AT91_SAM9X60_WDDIS);
> +		else if (!wdt->data->sam9x60_support &&
> +			 (!(reg & AT91_WDT_WDDIS)))
>  			wdt_write_nosleep(wdt, AT91_WDT_MR,
>  					  reg | AT91_WDT_WDDIS);
>  	}
> +
> +	if (wdt->data->sam9x60_support) {
> +		if (wdt->need_irq)
> +			wdt->ir = AT91_SAM9X60_PERINT;
> +		else
> +			wdt->mr |= AT91_SAM9X60_PERIODRST;
> +
> +		wdt_write(wdt, AT91_SAM9X60_IER, wdt->ir);
> +		wdt_write(wdt, AT91_SAM9X60_WLR, AT91_SAM9X60_SET_COUNTER(val));
> +	} else {
> +		wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
> +		wdt->mr |= AT91_WDT_SET_WDV(val);
> +
> +		if (wdt->need_irq)
> +			wdt->mr |= AT91_WDT_WDFIEN;
> +		else
> +			wdt->mr |= AT91_WDT_WDRSTEN;
> +	}
> +
> +	wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
> +
>  	return 0;
>  }
>  
> @@ -201,13 +259,14 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>  	struct sama5d4_wdt *wdt;
>  	void __iomem *regs;
>  	u32 irq = 0;
> -	u32 timeout;
>  	int ret;
>  
>  	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
>  	if (!wdt)
>  		return -ENOMEM;
>  
> +	wdt->data = of_device_get_match_data(&pdev->dev);
> +
>  	wdd = &wdt->wdd;
>  	wdd->timeout = WDT_DEFAULT_TIMEOUT;
>  	wdd->info = &sama5d4_wdt_info;
> @@ -224,15 +283,17 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>  
>  	wdt->reg_base = regs;
>  
> -	irq = irq_of_parse_and_map(dev->of_node, 0);
> -	if (!irq)
> -		dev_warn(dev, "failed to get IRQ from DT\n");
> -
>  	ret = of_sama5d4_wdt_init(dev->of_node, wdt);
>  	if (ret)
>  		return ret;
>  
> -	if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
> +	irq = irq_of_parse_and_map(dev->of_node, 0);
> +	if (!irq) {
> +		dev_warn(dev, "failed to get IRQ from DT\n");
> +		wdt->need_irq = 0;

Does it make sense to ignore that ?

> +	}
> +
> +	if (wdt->need_irq) {
>  		ret = devm_request_irq(dev, irq, sama5d4_wdt_irq_handler,
>  				       IRQF_SHARED | IRQF_IRQPOLL |
>  				       IRQF_NO_SUSPEND, pdev->name, pdev);
> @@ -244,11 +305,6 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>  
>  	watchdog_init_timeout(wdd, wdt_timeout, dev);
>  
> -	timeout = WDT_SEC2TICKS(wdd->timeout);
> -
> -	wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
> -	wdt->mr |= AT91_WDT_SET_WDV(timeout);
> -
>  	ret = sama5d4_wdt_init(wdt);
>  	if (ret)
>  		return ret;
> @@ -268,8 +324,21 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>  	return 0;
>  }
>  
> +static struct sama5d4_wdt_data sama5d4_config;
> +
> +static struct sama5d4_wdt_data sam9x60_config = {
> +	.sam9x60_support = 1,
> +};

Unless there is reason to believe that there will be other
configuration data, please just assign the flag value directly
to .data and add a variable to struct sama5d4_wdt to access it.
Please make that variable a bool.

> +
>  static const struct of_device_id sama5d4_wdt_of_match[] = {
> -	{ .compatible = "atmel,sama5d4-wdt", },
> +	{
> +		.compatible = "atmel,sama5d4-wdt",
> +		.data = &sama5d4_config,
> +	},
> +	{
> +		.compatible = "microchip,sam9x60-wdt",
> +		.data = &sam9x60_config,
> +	},
>  	{ }
>  };
>  MODULE_DEVICE_TABLE(of, sama5d4_wdt_of_match);
Eugen Hristev Nov. 7, 2019, 12:51 p.m. UTC | #2
On 29.10.2019 15:28, Guenter Roeck wrote:

> 
> On Mon, Oct 21, 2019 at 09:14:09AM +0000, Eugen.Hristev@microchip.com wrote:
>> From: Eugen Hristev <eugen.hristev@microchip.com>
>>
>> Add support for SAM9X60 WDT into sama5d4_wdt.
>> This means that this driver will have a platform data that will
>> hold differences.
>> Added definitions of different bits.
>> The ops functions will differentiate between the two hardware blocks.
>>
>> Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
>> ---
>>
>> Hello,
>>
>> This is a rework of the separate sam9x60 watchdog driver into a single driver
>> that supports both hardware blocks (sam9x60 and sama5d4)
>> This was done as suggested on the original patches on the mailing list.
>>
>> Thanks,
>> Eugen
>>
>>   drivers/watchdog/at91sam9_wdt.h |  14 +++++
>>   drivers/watchdog/sama5d4_wdt.c  | 127 +++++++++++++++++++++++++++++++---------
>>   2 files changed, 112 insertions(+), 29 deletions(-)
>>
>> diff --git a/drivers/watchdog/at91sam9_wdt.h b/drivers/watchdog/at91sam9_wdt.h
>> index 390941c..7a053fd 100644
>> --- a/drivers/watchdog/at91sam9_wdt.h
>> +++ b/drivers/watchdog/at91sam9_wdt.h
>> @@ -20,7 +20,10 @@
>>   #define AT91_WDT_MR		0x04			/* Watchdog Mode Register */
>>   #define		AT91_WDT_WDV		(0xfff << 0)		/* Counter Value */
>>   #define			AT91_WDT_SET_WDV(x)	((x) & AT91_WDT_WDV)
>> +#define		AT91_SAM9X60_PERIODRST	BIT(4)		/* Period Reset */
>> +#define		AT91_SAM9X60_RPTHRST	BIT(5)		/* Minimum Restart Period */
>>   #define		AT91_WDT_WDFIEN		(1     << 12)		/* Fault Interrupt Enable */
>> +#define		AT91_SAM9X60_WDDIS		BIT(12)		/* Disable */
>>   #define		AT91_WDT_WDRSTEN	(1     << 13)		/* Reset Processor */
>>   #define		AT91_WDT_WDRPROC	(1     << 14)		/* Timer Restart */
>>   #define		AT91_WDT_WDDIS		(1     << 15)		/* Watchdog Disable */
>> @@ -33,4 +36,15 @@
>>   #define		AT91_WDT_WDUNF		(1 << 0)		/* Watchdog Underflow */
>>   #define		AT91_WDT_WDERR		(1 << 1)		/* Watchdog Error */
>>   
>> +#define AT91_SAM9X60_VR		0x08			/* Watchdog Timer Value Register */
>> +
>> +#define AT91_SAM9X60_WLR		0x0c
>> +#define		AT91_SAM9X60_COUNTER	(0xfff << 0)		/* Watchdog Period Value */
>> +#define		AT91_SAM9X60_SET_COUNTER(x)	((x) & AT91_SAM9X60_COUNTER)
>> +
>> +#define AT91_SAM9X60_IER		0x14			/* Interrupt Enable Register */
>> +#define		AT91_SAM9X60_PERINT		BIT(0)		/* Period Interrupt Enable */
>> +#define AT91_SAM9X60_IDR		0x18			/* Interrupt Disable Register */
>> +#define AT91_SAM9X60_ISR		0x1c			/* Interrupt Status Register */
>> +
> 
> Those tabs are getting messy, and the mix of BIT() and shift is messy too.
> Mind cleaning it up a bit ? Especially, two tabs after #define doesn't really
> add value (use two spaces), and use BIT() throughout or not at all.
> 
>>   #endif
>> diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
>> index d193a60..b92afd7 100644
>> --- a/drivers/watchdog/sama5d4_wdt.c
>> +++ b/drivers/watchdog/sama5d4_wdt.c
>> @@ -2,7 +2,7 @@
>>   /*
>>    * Driver for Atmel SAMA5D4 Watchdog Timer
>>    *
>> - * Copyright (C) 2015 Atmel Corporation
>> + * Copyright (C) 2015-2019 Microchip Technology Inc. and its subsidiaries
>>    */
>>   
>>   #include <linux/delay.h>
>> @@ -11,6 +11,7 @@
>>   #include <linux/kernel.h>
>>   #include <linux/module.h>
>>   #include <linux/of.h>
>> +#include <linux/of_device.h>
>>   #include <linux/of_irq.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/reboot.h>
>> @@ -25,11 +26,18 @@
>>   
>>   #define WDT_SEC2TICKS(s)	((s) ? (((s) << 8) - 1) : 0)
>>   
>> +struct sama5d4_wdt_data {
>> +	const unsigned int		sam9x60_support;
>> +};
>> +
>>   struct sama5d4_wdt {
>> -	struct watchdog_device	wdd;
>> -	void __iomem		*reg_base;
>> -	u32			mr;
>> -	unsigned long		last_ping;
>> +	struct watchdog_device		wdd;
>> +	const struct sama5d4_wdt_data	*data;
>> +	void __iomem			*reg_base;
>> +	u32				mr;
>> +	u32				ir;
>> +	unsigned long			last_ping;
>> +	unsigned int			need_irq:1;
> 
> This can be a bool. Making it a bit just adds complexity to the code.
> 
>>   };
>>   
>>   static int wdt_timeout;
>> @@ -78,7 +86,12 @@ static int sama5d4_wdt_start(struct watchdog_device *wdd)
>>   {
>>   	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>>   
>> -	wdt->mr &= ~AT91_WDT_WDDIS;
>> +	if (wdt->data->sam9x60_support) {
>> +		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IER);
>> +		wdt->mr &= ~AT91_SAM9X60_WDDIS;
>> +	} else {
>> +		wdt->mr &= ~AT91_WDT_WDDIS;
>> +	}
>>   	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
>>   
>>   	return 0;
>> @@ -88,7 +101,12 @@ static int sama5d4_wdt_stop(struct watchdog_device *wdd)
>>   {
>>   	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>>   
>> -	wdt->mr |= AT91_WDT_WDDIS;
>> +	if (wdt->data->sam9x60_support) {
>> +		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IDR);
>> +		wdt->mr |= AT91_SAM9X60_WDDIS;
>> +	} else {
>> +		wdt->mr |= AT91_WDT_WDDIS;
>> +	}
>>   	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
>>   
>>   	return 0;
>> @@ -109,6 +127,14 @@ static int sama5d4_wdt_set_timeout(struct watchdog_device *wdd,
>>   	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
>>   	u32 value = WDT_SEC2TICKS(timeout);
>>   
>> +	if (wdt->data->sam9x60_support) {
>> +		wdt_write(wdt, AT91_SAM9X60_WLR,
>> +			  AT91_SAM9X60_SET_COUNTER(value));
>> +
>> +		wdd->timeout = timeout;
>> +		return 0;
>> +	}
>> +
>>   	wdt->mr &= ~AT91_WDT_WDV;
>>   	wdt->mr |= AT91_WDT_SET_WDV(value);
>>   
>> @@ -143,8 +169,14 @@ static const struct watchdog_ops sama5d4_wdt_ops = {
>>   static irqreturn_t sama5d4_wdt_irq_handler(int irq, void *dev_id)
>>   {
>>   	struct sama5d4_wdt *wdt = platform_get_drvdata(dev_id);
>> +	u32 reg;
>>   
>> -	if (wdt_read(wdt, AT91_WDT_SR)) {
>> +	if (wdt->data->sam9x60_support)
>> +		reg = wdt_read(wdt, AT91_SAM9X60_ISR);
>> +	else
>> +		reg = wdt_read(wdt, AT91_WDT_SR);
>> +
>> +	if (reg) {
>>   		pr_crit("Atmel Watchdog Software Reset\n");
>>   		emergency_restart();
>>   		pr_crit("Reboot didn't succeed\n");
>> @@ -157,13 +189,14 @@ static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
>>   {
>>   	const char *tmp;
>>   
>> -	wdt->mr = AT91_WDT_WDDIS;
>> +	if (wdt->data->sam9x60_support)
>> +		wdt->mr = AT91_SAM9X60_WDDIS;
>> +	else
>> +		wdt->mr = AT91_WDT_WDDIS;
>>   
>>   	if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
>>   	    !strcmp(tmp, "software"))
>> -		wdt->mr |= AT91_WDT_WDFIEN;
>> -	else
>> -		wdt->mr |= AT91_WDT_WDRSTEN;
>> +		wdt->need_irq = 1;
>>   
>>   	if (of_property_read_bool(np, "atmel,idle-halt"))
>>   		wdt->mr |= AT91_WDT_WDIDLEHLT;
>> @@ -176,21 +209,46 @@ static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
>>   
>>   static int sama5d4_wdt_init(struct sama5d4_wdt *wdt)
>>   {
>> -	u32 reg;
>> +	u32 reg, val;
>> +
>> +	val = WDT_SEC2TICKS(WDT_DEFAULT_TIMEOUT);
>>   	/*
>>   	 * When booting and resuming, the bootloader may have changed the
>>   	 * watchdog configuration.
>>   	 * If the watchdog is already running, we can safely update it.
>>   	 * Else, we have to disable it properly.
>>   	 */
>> -	if (wdt_enabled) {
>> -		wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
>> -	} else {
>> +	if (!wdt_enabled) {
>>   		reg = wdt_read(wdt, AT91_WDT_MR);
>> -		if (!(reg & AT91_WDT_WDDIS))
>> +		if (wdt->data->sam9x60_support && (!(reg & AT91_SAM9X60_WDDIS)))
>> +			wdt_write_nosleep(wdt, AT91_WDT_MR,
>> +					  reg | AT91_SAM9X60_WDDIS);
>> +		else if (!wdt->data->sam9x60_support &&
>> +			 (!(reg & AT91_WDT_WDDIS)))
>>   			wdt_write_nosleep(wdt, AT91_WDT_MR,
>>   					  reg | AT91_WDT_WDDIS);
>>   	}
>> +
>> +	if (wdt->data->sam9x60_support) {
>> +		if (wdt->need_irq)
>> +			wdt->ir = AT91_SAM9X60_PERINT;
>> +		else
>> +			wdt->mr |= AT91_SAM9X60_PERIODRST;
>> +
>> +		wdt_write(wdt, AT91_SAM9X60_IER, wdt->ir);
>> +		wdt_write(wdt, AT91_SAM9X60_WLR, AT91_SAM9X60_SET_COUNTER(val));
>> +	} else {
>> +		wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
>> +		wdt->mr |= AT91_WDT_SET_WDV(val);
>> +
>> +		if (wdt->need_irq)
>> +			wdt->mr |= AT91_WDT_WDFIEN;
>> +		else
>> +			wdt->mr |= AT91_WDT_WDRSTEN;
>> +	}
>> +
>> +	wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
>> +
>>   	return 0;
>>   }
>>   
>> @@ -201,13 +259,14 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>>   	struct sama5d4_wdt *wdt;
>>   	void __iomem *regs;
>>   	u32 irq = 0;
>> -	u32 timeout;
>>   	int ret;
>>   
>>   	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
>>   	if (!wdt)
>>   		return -ENOMEM;
>>   
>> +	wdt->data = of_device_get_match_data(&pdev->dev);
>> +
>>   	wdd = &wdt->wdd;
>>   	wdd->timeout = WDT_DEFAULT_TIMEOUT;
>>   	wdd->info = &sama5d4_wdt_info;
>> @@ -224,15 +283,17 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>>   
>>   	wdt->reg_base = regs;
>>   
>> -	irq = irq_of_parse_and_map(dev->of_node, 0);
>> -	if (!irq)
>> -		dev_warn(dev, "failed to get IRQ from DT\n");
>> -
>>   	ret = of_sama5d4_wdt_init(dev->of_node, wdt);
>>   	if (ret)
>>   		return ret;
>>   
>> -	if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
>> +	irq = irq_of_parse_and_map(dev->of_node, 0);
>> +	if (!irq) {
>> +		dev_warn(dev, "failed to get IRQ from DT\n");
>> +		wdt->need_irq = 0;
> 
> Does it make sense to ignore that ?

Hi Guenter,

Can you detail what exactly is ignored ?

> 
>> +	}
>> +
>> +	if (wdt->need_irq) {
>>   		ret = devm_request_irq(dev, irq, sama5d4_wdt_irq_handler,
>>   				       IRQF_SHARED | IRQF_IRQPOLL |
>>   				       IRQF_NO_SUSPEND, pdev->name, pdev);
>> @@ -244,11 +305,6 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>>   
>>   	watchdog_init_timeout(wdd, wdt_timeout, dev);
>>   
>> -	timeout = WDT_SEC2TICKS(wdd->timeout);
>> -
>> -	wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
>> -	wdt->mr |= AT91_WDT_SET_WDV(timeout);
>> -
>>   	ret = sama5d4_wdt_init(wdt);
>>   	if (ret)
>>   		return ret;
>> @@ -268,8 +324,21 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
>>   	return 0;
>>   }
>>   
>> +static struct sama5d4_wdt_data sama5d4_config;
>> +
>> +static struct sama5d4_wdt_data sam9x60_config = {
>> +	.sam9x60_support = 1,
>> +};
> 
> Unless there is reason to believe that there will be other
> configuration data, please just assign the flag value directly
> to .data and add a variable to struct sama5d4_wdt to access it.
> Please make that variable a bool.

There will be more configuration data for future products, but not at 
this moment. Do the change or keep it this way ?

I will do the other changes as requested.
Thanks for reviewing,

Eugen
> 
>> +
>>   static const struct of_device_id sama5d4_wdt_of_match[] = {
>> -	{ .compatible = "atmel,sama5d4-wdt", },
>> +	{
>> +		.compatible = "atmel,sama5d4-wdt",
>> +		.data = &sama5d4_config,
>> +	},
>> +	{
>> +		.compatible = "microchip,sam9x60-wdt",
>> +		.data = &sam9x60_config,
>> +	},
>>   	{ }
>>   };
>>   MODULE_DEVICE_TABLE(of, sama5d4_wdt_of_match);
> 
>
Guenter Roeck Nov. 7, 2019, 4:41 p.m. UTC | #3
On Thu, Nov 07, 2019 at 12:51:15PM +0000, Eugen.Hristev@microchip.com wrote:
> 
> >>   
> >> -	if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
> >> +	irq = irq_of_parse_and_map(dev->of_node, 0);
> >> +	if (!irq) {
> >> +		dev_warn(dev, "failed to get IRQ from DT\n");
> >> +		wdt->need_irq = 0;
> > 
> > Does it make sense to ignore that ?
> 
> Hi Guenter,
> 
> Can you detail what exactly is ignored ?
> 
The missing interrupt.

> >> +static struct sama5d4_wdt_data sama5d4_config;
> >> +
> >> +static struct sama5d4_wdt_data sam9x60_config = {
> >> +	.sam9x60_support = 1,
> >> +};
> > 
> > Unless there is reason to believe that there will be other
> > configuration data, please just assign the flag value directly
> > to .data and add a variable to struct sama5d4_wdt to access it.
> > Please make that variable a bool.
> 
> There will be more configuration data for future products, but not at 
> this moment. Do the change or keep it this way ?
> 
If not as part of this series, it is better to just assign
the flag directly. If there are changes coming at a later time
which indeed need a structure (with more than one object in it),
that structure can be added at that time.

Guenter
Eugen Hristev Nov. 7, 2019, 5:10 p.m. UTC | #4
On 07.11.2019 18:41, Guenter Roeck wrote:

> On Thu, Nov 07, 2019 at 12:51:15PM +0000, Eugen.Hristev@microchip.com wrote:
>>
>>>>    
>>>> -	if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
>>>> +	irq = irq_of_parse_and_map(dev->of_node, 0);
>>>> +	if (!irq) {
>>>> +		dev_warn(dev, "failed to get IRQ from DT\n");
>>>> +		wdt->need_irq = 0;
>>>
>>> Does it make sense to ignore that ?
>>
>> Hi Guenter,
>>
>> Can you detail what exactly is ignored ?
>>
> The missing interrupt.

Hi,

The interrupt is not mandatory for the work of the watchdog. So, if it's 
not available, we must act accordingly: just configure watchdog to reset 
the CPU.
If we have an IRQ, we can then act in the 'software-style' watchdog: 
trigger an IRQ first and try to allow the system to a safe reboot.
So , it's not ignoring, it's acting accordingly (later on, do not enable 
anything irq-related )


> 
>>>> +static struct sama5d4_wdt_data sama5d4_config;
>>>> +
>>>> +static struct sama5d4_wdt_data sam9x60_config = {
>>>> +	.sam9x60_support = 1,
>>>> +};
>>>
>>> Unless there is reason to believe that there will be other
>>> configuration data, please just assign the flag value directly
>>> to .data and add a variable to struct sama5d4_wdt to access it.
>>> Please make that variable a bool.
>>
>> There will be more configuration data for future products, but not at
>> this moment. Do the change or keep it this way ?
>>
> If not as part of this series, it is better to just assign
> the flag directly. If there are changes coming at a later time
> which indeed need a structure (with more than one object in it),
> that structure can be added at that time.

Ok, I will change it in next version.

Thanks,
Eugen
> 
> Guenter
> 
>
diff mbox series

Patch

diff --git a/drivers/watchdog/at91sam9_wdt.h b/drivers/watchdog/at91sam9_wdt.h
index 390941c..7a053fd 100644
--- a/drivers/watchdog/at91sam9_wdt.h
+++ b/drivers/watchdog/at91sam9_wdt.h
@@ -20,7 +20,10 @@ 
 #define AT91_WDT_MR		0x04			/* Watchdog Mode Register */
 #define		AT91_WDT_WDV		(0xfff << 0)		/* Counter Value */
 #define			AT91_WDT_SET_WDV(x)	((x) & AT91_WDT_WDV)
+#define		AT91_SAM9X60_PERIODRST	BIT(4)		/* Period Reset */
+#define		AT91_SAM9X60_RPTHRST	BIT(5)		/* Minimum Restart Period */
 #define		AT91_WDT_WDFIEN		(1     << 12)		/* Fault Interrupt Enable */
+#define		AT91_SAM9X60_WDDIS		BIT(12)		/* Disable */
 #define		AT91_WDT_WDRSTEN	(1     << 13)		/* Reset Processor */
 #define		AT91_WDT_WDRPROC	(1     << 14)		/* Timer Restart */
 #define		AT91_WDT_WDDIS		(1     << 15)		/* Watchdog Disable */
@@ -33,4 +36,15 @@ 
 #define		AT91_WDT_WDUNF		(1 << 0)		/* Watchdog Underflow */
 #define		AT91_WDT_WDERR		(1 << 1)		/* Watchdog Error */
 
+#define AT91_SAM9X60_VR		0x08			/* Watchdog Timer Value Register */
+
+#define AT91_SAM9X60_WLR		0x0c
+#define		AT91_SAM9X60_COUNTER	(0xfff << 0)		/* Watchdog Period Value */
+#define		AT91_SAM9X60_SET_COUNTER(x)	((x) & AT91_SAM9X60_COUNTER)
+
+#define AT91_SAM9X60_IER		0x14			/* Interrupt Enable Register */
+#define		AT91_SAM9X60_PERINT		BIT(0)		/* Period Interrupt Enable */
+#define AT91_SAM9X60_IDR		0x18			/* Interrupt Disable Register */
+#define AT91_SAM9X60_ISR		0x1c			/* Interrupt Status Register */
+
 #endif
diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index d193a60..b92afd7 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -2,7 +2,7 @@ 
 /*
  * Driver for Atmel SAMA5D4 Watchdog Timer
  *
- * Copyright (C) 2015 Atmel Corporation
+ * Copyright (C) 2015-2019 Microchip Technology Inc. and its subsidiaries
  */
 
 #include <linux/delay.h>
@@ -11,6 +11,7 @@ 
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/reboot.h>
@@ -25,11 +26,18 @@ 
 
 #define WDT_SEC2TICKS(s)	((s) ? (((s) << 8) - 1) : 0)
 
+struct sama5d4_wdt_data {
+	const unsigned int		sam9x60_support;
+};
+
 struct sama5d4_wdt {
-	struct watchdog_device	wdd;
-	void __iomem		*reg_base;
-	u32			mr;
-	unsigned long		last_ping;
+	struct watchdog_device		wdd;
+	const struct sama5d4_wdt_data	*data;
+	void __iomem			*reg_base;
+	u32				mr;
+	u32				ir;
+	unsigned long			last_ping;
+	unsigned int			need_irq:1;
 };
 
 static int wdt_timeout;
@@ -78,7 +86,12 @@  static int sama5d4_wdt_start(struct watchdog_device *wdd)
 {
 	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
 
-	wdt->mr &= ~AT91_WDT_WDDIS;
+	if (wdt->data->sam9x60_support) {
+		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IER);
+		wdt->mr &= ~AT91_SAM9X60_WDDIS;
+	} else {
+		wdt->mr &= ~AT91_WDT_WDDIS;
+	}
 	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
 	return 0;
@@ -88,7 +101,12 @@  static int sama5d4_wdt_stop(struct watchdog_device *wdd)
 {
 	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
 
-	wdt->mr |= AT91_WDT_WDDIS;
+	if (wdt->data->sam9x60_support) {
+		writel_relaxed(wdt->ir, wdt->reg_base + AT91_SAM9X60_IDR);
+		wdt->mr |= AT91_SAM9X60_WDDIS;
+	} else {
+		wdt->mr |= AT91_WDT_WDDIS;
+	}
 	wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
 	return 0;
@@ -109,6 +127,14 @@  static int sama5d4_wdt_set_timeout(struct watchdog_device *wdd,
 	struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
 	u32 value = WDT_SEC2TICKS(timeout);
 
+	if (wdt->data->sam9x60_support) {
+		wdt_write(wdt, AT91_SAM9X60_WLR,
+			  AT91_SAM9X60_SET_COUNTER(value));
+
+		wdd->timeout = timeout;
+		return 0;
+	}
+
 	wdt->mr &= ~AT91_WDT_WDV;
 	wdt->mr |= AT91_WDT_SET_WDV(value);
 
@@ -143,8 +169,14 @@  static const struct watchdog_ops sama5d4_wdt_ops = {
 static irqreturn_t sama5d4_wdt_irq_handler(int irq, void *dev_id)
 {
 	struct sama5d4_wdt *wdt = platform_get_drvdata(dev_id);
+	u32 reg;
 
-	if (wdt_read(wdt, AT91_WDT_SR)) {
+	if (wdt->data->sam9x60_support)
+		reg = wdt_read(wdt, AT91_SAM9X60_ISR);
+	else
+		reg = wdt_read(wdt, AT91_WDT_SR);
+
+	if (reg) {
 		pr_crit("Atmel Watchdog Software Reset\n");
 		emergency_restart();
 		pr_crit("Reboot didn't succeed\n");
@@ -157,13 +189,14 @@  static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
 {
 	const char *tmp;
 
-	wdt->mr = AT91_WDT_WDDIS;
+	if (wdt->data->sam9x60_support)
+		wdt->mr = AT91_SAM9X60_WDDIS;
+	else
+		wdt->mr = AT91_WDT_WDDIS;
 
 	if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
 	    !strcmp(tmp, "software"))
-		wdt->mr |= AT91_WDT_WDFIEN;
-	else
-		wdt->mr |= AT91_WDT_WDRSTEN;
+		wdt->need_irq = 1;
 
 	if (of_property_read_bool(np, "atmel,idle-halt"))
 		wdt->mr |= AT91_WDT_WDIDLEHLT;
@@ -176,21 +209,46 @@  static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
 
 static int sama5d4_wdt_init(struct sama5d4_wdt *wdt)
 {
-	u32 reg;
+	u32 reg, val;
+
+	val = WDT_SEC2TICKS(WDT_DEFAULT_TIMEOUT);
 	/*
 	 * When booting and resuming, the bootloader may have changed the
 	 * watchdog configuration.
 	 * If the watchdog is already running, we can safely update it.
 	 * Else, we have to disable it properly.
 	 */
-	if (wdt_enabled) {
-		wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
-	} else {
+	if (!wdt_enabled) {
 		reg = wdt_read(wdt, AT91_WDT_MR);
-		if (!(reg & AT91_WDT_WDDIS))
+		if (wdt->data->sam9x60_support && (!(reg & AT91_SAM9X60_WDDIS)))
+			wdt_write_nosleep(wdt, AT91_WDT_MR,
+					  reg | AT91_SAM9X60_WDDIS);
+		else if (!wdt->data->sam9x60_support &&
+			 (!(reg & AT91_WDT_WDDIS)))
 			wdt_write_nosleep(wdt, AT91_WDT_MR,
 					  reg | AT91_WDT_WDDIS);
 	}
+
+	if (wdt->data->sam9x60_support) {
+		if (wdt->need_irq)
+			wdt->ir = AT91_SAM9X60_PERINT;
+		else
+			wdt->mr |= AT91_SAM9X60_PERIODRST;
+
+		wdt_write(wdt, AT91_SAM9X60_IER, wdt->ir);
+		wdt_write(wdt, AT91_SAM9X60_WLR, AT91_SAM9X60_SET_COUNTER(val));
+	} else {
+		wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
+		wdt->mr |= AT91_WDT_SET_WDV(val);
+
+		if (wdt->need_irq)
+			wdt->mr |= AT91_WDT_WDFIEN;
+		else
+			wdt->mr |= AT91_WDT_WDRSTEN;
+	}
+
+	wdt_write_nosleep(wdt, AT91_WDT_MR, wdt->mr);
+
 	return 0;
 }
 
@@ -201,13 +259,14 @@  static int sama5d4_wdt_probe(struct platform_device *pdev)
 	struct sama5d4_wdt *wdt;
 	void __iomem *regs;
 	u32 irq = 0;
-	u32 timeout;
 	int ret;
 
 	wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
 	if (!wdt)
 		return -ENOMEM;
 
+	wdt->data = of_device_get_match_data(&pdev->dev);
+
 	wdd = &wdt->wdd;
 	wdd->timeout = WDT_DEFAULT_TIMEOUT;
 	wdd->info = &sama5d4_wdt_info;
@@ -224,15 +283,17 @@  static int sama5d4_wdt_probe(struct platform_device *pdev)
 
 	wdt->reg_base = regs;
 
-	irq = irq_of_parse_and_map(dev->of_node, 0);
-	if (!irq)
-		dev_warn(dev, "failed to get IRQ from DT\n");
-
 	ret = of_sama5d4_wdt_init(dev->of_node, wdt);
 	if (ret)
 		return ret;
 
-	if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
+	irq = irq_of_parse_and_map(dev->of_node, 0);
+	if (!irq) {
+		dev_warn(dev, "failed to get IRQ from DT\n");
+		wdt->need_irq = 0;
+	}
+
+	if (wdt->need_irq) {
 		ret = devm_request_irq(dev, irq, sama5d4_wdt_irq_handler,
 				       IRQF_SHARED | IRQF_IRQPOLL |
 				       IRQF_NO_SUSPEND, pdev->name, pdev);
@@ -244,11 +305,6 @@  static int sama5d4_wdt_probe(struct platform_device *pdev)
 
 	watchdog_init_timeout(wdd, wdt_timeout, dev);
 
-	timeout = WDT_SEC2TICKS(wdd->timeout);
-
-	wdt->mr |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(MAX_WDT_TIMEOUT));
-	wdt->mr |= AT91_WDT_SET_WDV(timeout);
-
 	ret = sama5d4_wdt_init(wdt);
 	if (ret)
 		return ret;
@@ -268,8 +324,21 @@  static int sama5d4_wdt_probe(struct platform_device *pdev)
 	return 0;
 }
 
+static struct sama5d4_wdt_data sama5d4_config;
+
+static struct sama5d4_wdt_data sam9x60_config = {
+	.sam9x60_support = 1,
+};
+
 static const struct of_device_id sama5d4_wdt_of_match[] = {
-	{ .compatible = "atmel,sama5d4-wdt", },
+	{
+		.compatible = "atmel,sama5d4-wdt",
+		.data = &sama5d4_config,
+	},
+	{
+		.compatible = "microchip,sam9x60-wdt",
+		.data = &sam9x60_config,
+	},
 	{ }
 };
 MODULE_DEVICE_TABLE(of, sama5d4_wdt_of_match);