[PATCH] ARM: shmobile: Check MD21 at SMP boot in case of APMU

Geert Uytterhoeven
2014-02-17T08:53:02Z

On Mon, Feb 17, 2014 at 7:31 AM, Magnus Damm <magnus.damm@gmail.com> wrote:
> From: Magnus Damm <damm@opensource.se>
>
> On R-Car Gen2 SoCs such as r8a7790 and r8a7791 the hardware boot
> mode bit MD21 indicates if hardware debug mode is enabled or not.
>
> In case hardware debug mode is enabled print a warning and refrain
> from booting secondary CPU cores. Without this patch Koelsch boards
> with SW8-4 set to OFF will hang at SMP boot.

Ah, mine was set to OFF.

> Signed-off-by: Magnus Damm <damm@opensource.se>

Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

with one minor nit:

> int shmobile_smp_apmu_boot_secondary(unsigned int cpu, struct task_struct *idle)
> {
> + /* Refrain boot when hardware debug mode is enabled */
> + if (rcar_gen2_read_mode_pins() & BIT(21)) {
> + pr_warn("Unable to boot CPU%d when MD21 is set\n", cpu);

%u

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds