commit 827a108e354db633698f0b4a10c1ffd2b1f8d1d0 upstream
When the CPU comes out of suspend, the firmware may have modified the OS Double Lock Register. Save it in an unused slot of cpu_suspend_ctx, and restore it on resume.
Signed-off-by: Jean-Philippe Brucker jean-philippe.brucker@arm.com Signed-off-by: Will Deacon will.deacon@arm.com --- Modified for v4.9 backport: 623b476fc815 and 6d99b68933fb are missing in v4.9, but the conflict is easily resolved.
Tested on Juno with cpuidle. --- arch/arm64/mm/proc.S | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index f5fde8d389c9..3ceec224d3d2 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -64,17 +64,18 @@ ENTRY(cpu_do_suspend) mrs x2, tpidr_el0 mrs x3, tpidrro_el0 mrs x4, contextidr_el1 - mrs x5, cpacr_el1 - mrs x6, tcr_el1 - mrs x7, vbar_el1 - mrs x8, mdscr_el1 - mrs x9, oslsr_el1 - mrs x10, sctlr_el1 + mrs x5, osdlr_el1 + mrs x6, cpacr_el1 + mrs x7, tcr_el1 + mrs x8, vbar_el1 + mrs x9, mdscr_el1 + mrs x10, oslsr_el1 + mrs x11, sctlr_el1 stp x2, x3, [x0] - stp x4, xzr, [x0, #16] - stp x5, x6, [x0, #32] - stp x7, x8, [x0, #48] - stp x9, x10, [x0, #64] + stp x4, x5, [x0, #16] + stp x6, x7, [x0, #32] + stp x8, x9, [x0, #48] + stp x10, x11, [x0, #64] ret ENDPROC(cpu_do_suspend)
@@ -96,8 +97,8 @@ ENTRY(cpu_do_resume) msr cpacr_el1, x6
/* Don't change t0sz here, mask those bits when restoring */ - mrs x5, tcr_el1 - bfi x8, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH + mrs x7, tcr_el1 + bfi x8, x7, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH
msr tcr_el1, x8 msr vbar_el1, x9 @@ -115,6 +116,7 @@ ENTRY(cpu_do_resume) /* * Restore oslsr_el1 by writing oslar_el1 */ + msr osdlr_el1, x5 ubfx x11, x11, #1, #1 msr oslar_el1, x11 reset_pmuserenr_el0 x0 // Disable PMU access from EL0