When going to deep idle we need to disable the SoC snooping (aka hardware coherency support). Playing with the coherency fabric requires to use assembly code to be sure that the compiler doesn't reorder the instructions nor do wrong optimization.
Signed-off-by: Gregory CLEMENT <[email protected]> --- arch/arm/mach-mvebu/coherency_ll.S | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/arch/arm/mach-mvebu/coherency_ll.S b/arch/arm/mach-mvebu/coherency_ll.S index f2e2e8677c4b..6828f9f157b0 100644 --- a/arch/arm/mach-mvebu/coherency_ll.S +++ b/arch/arm/mach-mvebu/coherency_ll.S @@ -102,6 +102,26 @@ ENTRY(ll_enable_coherency) mov pc, lr ENDPROC(ll_enable_coherency) +ENTRY(ll_disable_coherency) + /* + * r0 being untouched in ll_get_coherency_base and + * ll_get_cpuid, we can use it to save lr modifing it with the + * following bl + */ + mov r0, lr + bl ll_get_coherency_base + bl ll_get_cpuid + mov lr, r0 + add r0, r1, #ARMADA_XP_CFB_CTL_REG_OFFSET +1: + ldrex r2, [r0] + bic r2, r2, r3 + strex r1, r2, [r0] + cmp r1, #0 + bne 1b + dsb + mov pc, lr +ENDPROC(ll_disable_coherency) .align 2 3: -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
