diff --git a/arch/arm/common/Makefile b/arch/arm/common/Makefile index b070671033ae..9ec273188ccb 100644 --- a/arch/arm/common/Makefile +++ b/arch/arm/common/Makefile @@ -11,4 +11,4 @@ obj-$(CONFIG_SHARP_PARAM) += sharpsl_param.o obj-$(CONFIG_SHARP_SCOOP) += scoop.o obj-$(CONFIG_PCI_HOST_ITE8152) += it8152.o obj-$(CONFIG_ARM_TIMER_SP804) += timer-sp.o -obj-$(CONFIG_MCPM) += mcpm_head.o mcpm_entry.o +obj-$(CONFIG_MCPM) += mcpm_head.o mcpm_entry.o vlock.o diff --git a/arch/arm/common/mcpm_head.S b/arch/arm/common/mcpm_head.S index 7d729bd72674..8178705c4b24 100644 --- a/arch/arm/common/mcpm_head.S +++ b/arch/arm/common/mcpm_head.S @@ -16,6 +16,8 @@ #include #include +#include "vlock.h" + .if MCPM_SYNC_CLUSTER_CPUS .error "cpus must be the first member of struct mcpm_sync_struct" .endif @@ -69,10 +71,11 @@ ENTRY(mcpm_entry_point) * position independent way. */ adr r5, 3f - ldmia r5, {r6, r7, r8} + ldmia r5, {r6, r7, r8, r11} add r6, r5, r6 @ r6 = mcpm_entry_vectors ldr r7, [r5, r7] @ r7 = mcpm_power_up_setup_phys add r8, r5, r8 @ r8 = mcpm_sync + add r11, r5, r11 @ r11 = first_man_locks mov r0, #MCPM_SYNC_CLUSTER_SIZE mla r8, r0, r10, r8 @ r8 = sync cluster base @@ -86,13 +89,22 @@ ENTRY(mcpm_entry_point) @ At this point, the cluster cannot unexpectedly enter the GOING_DOWN @ state, because there is at least one active CPU (this CPU). - @ Note: the following is racy as another CPU might be testing - @ the same flag at the same moment. That'll be fixed later. + mov r0, #VLOCK_SIZE + mla r11, r0, r10, r11 @ r11 = cluster first man lock + mov r0, r11 + mov r1, r9 @ cpu + bl vlock_trylock @ implies DMB + + cmp r0, #0 @ failed to get the lock? + bne mcpm_setup_wait @ wait for cluster setup if so + ldrb r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER] cmp r0, #CLUSTER_UP @ cluster already up? bne mcpm_setup @ if not, set up the cluster - @ Otherwise, skip setup: + @ Otherwise, release the first man lock and skip setup: + mov r0, r11 + bl vlock_unlock b mcpm_setup_complete mcpm_setup: @@ -142,6 +154,19 @@ mcpm_setup_leave: dsb sev + mov r0, r11 + bl vlock_unlock @ implies DMB + b mcpm_setup_complete + + @ In the contended case, non-first men wait here for cluster setup + @ to complete: +mcpm_setup_wait: + ldrb r0, [r8, #MCPM_SYNC_CLUSTER_CLUSTER] + cmp r0, #CLUSTER_UP + wfene + bne mcpm_setup_wait + dmb + mcpm_setup_complete: @ If a platform-specific CPU setup hook is needed, it is @ called from here. @@ -173,11 +198,17 @@ mcpm_entry_gated: 3: .word mcpm_entry_vectors - . .word mcpm_power_up_setup_phys - 3b .word mcpm_sync - 3b + .word first_man_locks - 3b ENDPROC(mcpm_entry_point) .bss - .align 5 + + .align CACHE_WRITEBACK_ORDER + .type first_man_locks, #object +first_man_locks: + .space VLOCK_SIZE * MAX_NR_CLUSTERS + .align CACHE_WRITEBACK_ORDER .type mcpm_entry_vectors, #object ENTRY(mcpm_entry_vectors) diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c index 1bed82a0a9e0..3f088225e71c 100644 --- a/arch/arm/kernel/asm-offsets.c +++ b/arch/arm/kernel/asm-offsets.c @@ -150,6 +150,7 @@ int main(void) DEFINE(DMA_TO_DEVICE, DMA_TO_DEVICE); DEFINE(DMA_FROM_DEVICE, DMA_FROM_DEVICE); BLANK(); + DEFINE(CACHE_WRITEBACK_ORDER, __CACHE_WRITEBACK_ORDER); DEFINE(CACHE_WRITEBACK_GRANULE, __CACHE_WRITEBACK_GRANULE); BLANK(); #ifdef CONFIG_KVM_ARM_HOST