Re: [Xen-devel] [PATCH v2 1/2] xen/arm64: Add Support for Allwinner H5 (sun50i)

[Julien Grall <julien.grall@xxxxxxx>]

On 28/09/17 23:49, Andre Przywara wrote:
> Hi,
Hi,

> On 09/28/2017 01:03 PM, Julien Grall wrote:
> > >   #define SUNXI_WDT_MODE            0x04
> > > -#define SUNXI_WDT_MODEADDR        (SUNXI_WDT_BASE + SUNXI_WDT_MODE)
> > >   #define SUNXI_WDT_MODE_EN         (1 << 0)
> > >   #define SUNXI_WDT_MODE_RST_EN     (1 << 1)
> > > -static void sunxi_reset(void)
> > > +static void sunxi_reset(u32 base)
> > >   {
> > >       void __iomem *wdt;
> > > -    wdt = ioremap_nocache(SUNXI_WDT_MODEADDR & PAGE_MASK, PAGE_SIZE);
> > > +    wdt = ioremap_nocache((base + SUNXI_WDT_MODE) & PAGE_MASK, 
> > > PAGE_SIZE);
> > >       if ( !wdt )
> > >       {
> > >           dprintk(XENLOG_ERR, "Unable to map watchdog register!\n");
> > > @@ -42,19 +42,35 @@ static void sunxi_reset(void)
> > >       /* Enable watchdog to trigger a reset after 500 ms: */
> > >       writel(SUNXI_WDT_MODE_EN | SUNXI_WDT_MODE_RST_EN,
> > > -      wdt + (SUNXI_WDT_MODEADDR & ~PAGE_MASK));
> > > +      wdt + ((base + SUNXI_WDT_MODE) & ~PAGE_MASK));
> > >       iounmap(wdt); >
> > >       for (;;)
> > >           wfi();
> > >   }
> > >
> > > -static const char * const sunxi_dt_compat[] __initconst =
> > > +static void sunxi_a20_reset(void)
> > > +{
> > > +    sunxi_reset(SUNXI_WDT_A20_BASE);
> > > +}
> > > +
> > > +static void sunxi_h5_reset(void)
> > > +{
> > > +    sunxi_reset(SUNXI_WDT_H5_BASE);
> > If I read correctly the Device-Tree for 
> > (linux/arch/arm64/boot/dts/allwinner/sun50i-h5.dtsi), the firmware is 
> > supporting PSCI 0.2.
> > PSCI 0.2 provides call for power-off/reset, so implementation the 
> > reset callback should not be necessary.
> Yes, indeed, on the H5 PSCI 0.2 reset works via ATF.
>
> > Similarly the cubietrucks we have in osstest are using PSCI 0.2 and 
> > should not need the reset. Andre do you know if it is the case for all 
> > the A20?
> It claims 0.2, but in fact it seems not to be fully compliant, as (from 
> looking at the code) U-Boot lacks the reset and poweroff calls. But it 
> looks rather straight-forward to add them, as U-Boot knows how to reset 
> and one would just need to wire up psci_system_reset to this.
Hmmm ok :/. Please ignore my suggestion below to drop reset callback for 
all the allwinner platforms.
Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel