Re: [PATCH v2] xen/rpi4: implement watchdog-based reset

[Julien Grall <julien@xxxxxxx>]

Hi Stefano,

On 02/10/2020 21:47, Stefano Stabellini wrote:
> The preferred methord to reboot RPi4 is PSCI. If it is not available,
s/methord/method/

> +
> +#define PM_PASSWORD                 0x5a000000
> +#define PM_RSTC                     0x1c
> +#define PM_WDOG                     0x24
> +#define PM_RSTC_WRCFG_FULL_RESET    0x00000020
> +#define PM_RSTC_WRCFG_CLR           0xffffffcf
> +
> +static void __iomem *rpi4_map_watchdog(void)
> +{
> +    void __iomem *base;
> +    struct dt_device_node *node;
> +    paddr_t start, len;
> +    int ret;
> +
> +    node = dt_find_compatible_node(NULL, NULL, "brcm,bcm2835-pm");
> +    if ( !node )
> +        return NULL;
> +
> +    ret = dt_device_get_address(node, 0, &start, &len);
> +    if ( ret )
> +    {
> +        printk("Cannot read watchdog register address\n");
> +        return NULL;
> +    }
> +
> +    base = ioremap_nocache(start & PAGE_MASK, PAGE_SIZE);
> +    if ( !base )
> +    {
> +        dprintk(XENLOG_ERR, "Unable to map watchdog register!\n");
NIT: I would suggest to use printk() rather than dprintk. It would be 
useful for a normal user to know that we didn't manage to reset the 
platform and why.
Acked-by: Julien Grall <jgrall@xxxxxxxxxx>

Cheers,

--
Julien Grall