Re: [PATCH v3] aspeed: Add boot stub for smp booting

[Joel Stanley <joel@jms.id.au>]

On Mon, 4 May 2020 at 08:20, Joel Stanley <joel@jms.id.au> wrote:
...

> v3: Use WFI instead of WFE
> v2: test for number of CPUs

> +static void aspeed_write_smpboot(ARMCPU *cpu,
> +                                 const struct arm_boot_info *info)
> +{
> +    static const uint32_t poll_mailbox_ready[] = {
> +        /*
> +         * r2 = per-cpu go sign value
> +         * r1 = AST_SMP_MBOX_FIELD_ENTRY
> +         * r0 = AST_SMP_MBOX_FIELD_GOSIGN
> +         */
> +        0xee100fb0,  /* mrc     p15, 0, r0, c0, c0, 5 */
> +        0xe21000ff,  /* ands    r0, r0, #255          */
> +        0xe59f201c,  /* ldr     r2, [pc, #28]         */
> +        0xe1822000,  /* orr     r2, r2, r0            */
> +
> +        0xe59f1018,  /* ldr     r1, [pc, #24]         */
> +        0xe59f0018,  /* ldr     r0, [pc, #24]         */
> +
> +        0xe320f003,  /* wfi                           */

I was wrong, wfi does not work in this case. I must have made a
mistake when testing.

Cédric, can you please confirm my testing is correct? I was using
today's linux next, but anything newer than Linux 5.4 should have the
same result.

Peter, can you please take v2 of this patch set instead of v3?

If you've already added it to you queue I can send a follow up to fix it.

Cheers,

Joel