[U-Boot] [PATCH 1/2] sun7i: Add support for taking CPUs offline via PSCI

[Ian Campbell]

On Mon, 2014-12-15 at 12:37 +0100, Jan Kiszka wrote:
> +	movw	r8, #(GICC_BASE & 0xffff)
> +	movt	r8, #(GICC_BASE >> 16)
> +	ldr	r9, [r8, #GICC_IAR]
> +	movw	r10, #0x3ff
> +	movt	r10, #0
> +	cmp	r9, r10
> +	beq	out
> +	movw	r10, #0x3fe
> +	cmp	r9, r10
> +	beq	out
> +	str	r9, [r8, #GICC_EOIR]
> +	dsb

This block could do with a leading comment like the others. It is
reading IAR and discarding any spurious interrupts (1022+1023), but not
explicitly checking for SGI15, presumably because it can be asserted
that there is no other possible interrupt which can end up here, is that
right?

> +
> +.globl	psci_cpu_off
> +psci_cpu_off:
> +	mrc	p15, 0, r0, c1, c0, 0		@ SCTLR
> +	bic	r0, r0, #(1 << 2)		@ Clear C bit
> +	mcr	p15, 0, r0, c1, c0, 0		@ SCTLR
> +	isb
> +	dsb
> +
> +	bl	v7_flush_dcache_all
> +
> +	clrex					@ Why???

Anyone got any clues? (Just curiosity, not a blocker)

Apart from the comment:
Acked-by: Ian Campbell <ijc at hellion.org.uk>

Ian.