[U-Boot] [PATCHv4 4/7] ARMv8/Layerscape: switch SMP method to spin-table when the PSCI isn't available

[Zhiqiang Hou]

Hi York,

Thanks a lot for your comments and suggestions!

> -----Original Message-----
> From: York Sun [mailto:york.sun at nxp.com]
> Sent: 2016年5月28日 2:06
> To: Zhiqiang Hou <zhiqiang.hou at nxp.com>; u-boot at lists.denx.de;
> albert.u.boot at aribaud.net; scottwood at freescale.com;
> Mingkai.hu at freescale.com; yorksun at freescale.com; leoli at freescale.com;
> prabhakar at freescale.com; bhupesh.sharma at freescale.com
> Subject: Re: [PATCHv4 4/7] ARMv8/Layerscape: switch SMP method to spin-table
> when the PSCI isn't available
> 
> On 05/23/2016 04:49 AM, Zhiqiang Hou wrote:
> > From: Hou Zhiqiang <Zhiqiang.Hou at nxp.com>
> >
> > If the PSCI and PPA is ready, skip the fixup for spin-table and waking
> > secondary cores. If not, change SMP method to spin-table, and the
> > device node of PSCI will be removed.
> 
> I don't see how you change the boot method to spin-table. It has been spin-table
> all the way. Actually you change the boot method to psci when the image is valid.
> 

If the macro CONFIG_FSL_LS_PPA && CONFIG_ARMV8_PSCI is defined but the
sec firmware is invalid, the PSCI node will be removed, then the other code in the
function ft_fixup_cpu() will change the boot method to spin-table. Otherwise the
function ft_fixup_cpu() will return directly.

> >
> > Signed-off-by: Hou Zhiqiang <Zhiqiang.Hou at nxp.com>
> > ---
> > V4:
> >  - Reordered this patch.
> 
> <snip>
> 
> >  int fdt_fixup_phy_connection(void *blob, int offset, phy_interface_t
> > phyc)  { @@ -36,7 +39,35 @@ void ft_fixup_cpu(void *blob)
> >  	int addr_cells;
> >  	u64 val, core_id;
> >  	size_t *boot_code_size = &(__secondary_boot_code_size);
> > +#if defined(CONFIG_FSL_LS_PPA) && defined(CONFIG_ARMV8_PSCI)
> > +	int node;
> > +#endif
> > +
> > +#if defined(CONFIG_FSL_LS_PPA) && defined(CONFIG_ARMV8_PSCI)
> > +	if (sec_firmware_validate()) {
> 
> This function name is confusing. It returns non-zero when the image is not valid.
> Please consider to change the name.
 
Yes, will change the name in next version.

> Does the existence of such image guarantee it has been loaded successfully?
> Would it be possible to detect the psci feature is up and running?

Your suggestion is great, but I'm not sure if there is an interface to check the psci feature.
Will check it and update, thanks!

> 
> > +		/* remove psci DT node */
> > +		node = fdt_path_offset(blob, "/psci");
> > +		if (node >= 0)
> > +			goto remove_psci_node;
> > +
> > +		node = fdt_node_offset_by_compatible(blob, -1, "arm,psci");
> > +		if (node >= 0)
> > +			goto remove_psci_node;
> >
> > +		node = fdt_node_offset_by_compatible(blob, -1, "arm,psci-0.2");
> > +		if (node >= 0)
> > +			goto remove_psci_node;
> > +
> > +		node = fdt_node_offset_by_compatible(blob, -1, "arm,psci-1.0");
> > +		if (node >= 0)
> > +			goto remove_psci_node;
> > +
> > +remove_psci_node:
> > +		if (node >= 0)
> > +			fdt_del_node(blob, node);
> > +	} else
> > +		return;
> > +#endif
> >  	off = fdt_path_offset(blob, "/cpus");
> >  	if (off < 0) {
> >  		puts("couldn't find /cpus node\n");
> >
> 
> I see you are removing the psci nodes. Do you need to update the cpus nodes with
> enable-method here? You have it done in next patch cpu_update_dt_psci().

If the macro CONFIG_FSL_LS_PPA && CONFIG_ARMV8_PSCI isn't defined or the sec
firmware is invalid, the enable-method will be changed to spin-table in this function.

Thanks,
Zhiqiang