[PATCH 2/5] ARM: add SMP support for Broadcom mobile SoCs

[elder@linaro.org (Alex Elder)]

On 04/03/2014 09:18 PM, Alex Elder wrote:
> This patch adds SMP support for BCM281XX and BCM21664 family SoCs.
> 
> This feature is controlled with a distinct config option such that a
> SMP-enabled multi-v7 binary can be configured to run these SoCs in
> uniprocessor mode.  Since this SMP functionality is used for
> multiple Broadcom mobile chip families the config option is called
> ARCH_BCM_MOBILE_SMP (for lack of a better name).
> 
> On SoCs of this type, the secondary core is not held in reset on
> power-on.  Instead it loops in a ROM-based holding pen.  To release
> it, one must write into a special register a jump address whose
> low-order bits have been replaced with a secondary core's id, then
> trigger an event with SEV.  On receipt of an event, the ROM code
> will examine the register's contents, and if the low-order bits
> match its cpu id, it will clear them and write the value back to the
> register just prior to jumping to the address specified.
> 
> The location of the special register is defined in the device tree
> using a "secondary-boot-reg" property in a node whose "enable-method"
> matches.
> 
> Derived from code originally provided by Ray Jui <rjui@broadcom.com>
> 
> Signed-off-by: Alex Elder <elder@linaro.org>
> ---

. . .

> diff --git a/arch/arm/mach-bcm/Makefile b/arch/arm/mach-bcm/Makefile
> index b2279e3..929579f 100644
> --- a/arch/arm/mach-bcm/Makefile
> +++ b/arch/arm/mach-bcm/Makefile
> @@ -15,7 +15,10 @@ obj-$(CONFIG_ARCH_BCM_281XX)	+= board_bcm281xx.o
>  plus_sec := $(call as-instr,.arch_extension sec,+sec)
>  
>  # BCM21664
> -obj-$(CONFIG_ARCH_BCM_21664)	+= board_bcm21664.o
> +obj-$(CONFIG_ARCH_BCM_21664)	:= board_bcm21664.o

The above was a mistake, it should still be +=.

(I'll fix it.)

. . .