[PATCH 0/2] Fix secondary CPU boot for thumb2 kernels
catalin.marinas at arm.com
Thu Jan 29 07:46:25 PST 2015
On Wed, Jan 28, 2015 at 08:22:41PM +0000, Stephen Boyd wrote:
> On 01/21/15 11:48, Stephen Boyd wrote:
> > Currently I can't boot up secondary CPUs on qcom platforms when I
> > compile the kernel for THUMB2 mode. This is because we always enter
> > the kernel in ARM mode regardless of what mode the kernel is compiled
> > for. This patchset adds a small wrapper to secondary_startup() called
> > secondary_startup_arm() that allows us to switch into THUMB2 mode if
> > we need to. If the kernel is compiled for ARM mode it shouldn't have
> > any effect.
> > Stephen Boyd (2):
> > ARM: Add a secondary_startup that assumes ARM mode
> > ARM: qcom: Use secondary_startup_arm()
> > arch/arm/kernel/head.S | 7 +++++++
> > arch/arm/mach-qcom/platsmp.c | 4 ++--
> > 2 files changed, 9 insertions(+), 2 deletions(-)
> Any comments here? Perhaps I can send this through the patch tracker?
FWIW, they look fine to me.
Acked-by: Catalin Marinas <catalin.marinas at arm.com>
I guess the reason it works fine on other platforms is because the
secondary start address we pass to firmware has bit 0 set and this
causes the jump to the kernel in Thumb-2 mode.
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