Resent due to gmail adding HTML, sorry for the noise. Am Montag, den 11.01.2021, 18:49 +0100 schrieb Ahmad Fatoum: > > On 11.01.21 16:17, Max Krummenacher wrote: > > When the kernel is configured to use the Thumb-2 instruction set > > "suspend-to-memory" fails to resume. Observed on a Colibri iMX6ULL > > (i.MX 6ULL) and Apalis iMX6 (i.MX 6Q). > > > > It looks like the CPU resumes unconditionally in ARM instruction mode > > and then chokes on the presented Thumb-2 code it should execute. > > > > Fix this by using the arm instruction set for all code in > > suspend-imx6.S. > > > > Signed-off-by: Max Krummenacher <[email protected]> > > > > --- > > > > arch/arm/mach-imx/suspend-imx6.S | 1 + > > 1 file changed, 1 insertion(+) > > > > diff --git a/arch/arm/mach-imx/suspend-imx6.S > > b/arch/arm/mach-imx/suspend-imx6.S > > index 1eabf2d2834be..e06f946b75b96 100644 > > --- a/arch/arm/mach-imx/suspend-imx6.S > > +++ b/arch/arm/mach-imx/suspend-imx6.S > > @@ -67,6 +67,7 @@ > > #define MX6Q_CCM_CCR 0x0 > > > > .align 3 > > + .arm > > You had a return to thumb at the end of this subroutine in the cover letter, > yet here it's omitted. Why?
Now the whole subroutine is compiled for ARM and the return address has bit 0 set so that on jumping back to the caller the CPU will switch back to Thumb-2. Probably the return to Thumb-2 isn't needed in the cover letter solution and it would also work to finish the subroutine in ARM instruction set. However it looks strange to me if a function which begins with the ARM instruction set would come to the return in Thumb-2. > > > > > .macro sync_l2_cache > > > >
