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Posted to commits@nuttx.apache.org by ma...@apache.org on 2022/09/28 01:33:19 UTC
[incubator-nuttx] branch master updated: armv7-a: SMP hande all cores start at same time
This is an automated email from the ASF dual-hosted git repository.
masayuki pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/incubator-nuttx.git
The following commit(s) were added to refs/heads/master by this push:
new 078a0486f5 armv7-a: SMP hande all cores start at same time
078a0486f5 is described below
commit 078a0486f5e2cdd9972b375bad052dd53c742e18
Author: ligd <li...@xiaomi.com>
AuthorDate: Tue Sep 27 00:53:28 2022 +0800
armv7-a: SMP hande all cores start at same time
In SMP mode, if all cores start at same time, all from __start(),
then only primary need do initialize, so others core should wait
primary, use 'sev' let the non-primary continue to __cpuN_start().
Signed-off-by: ligd <li...@xiaomi.com>
---
arch/arm/src/armv7-a/arm_head.S | 26 ++++++++++++++++++++++++++
arch/arm/src/armv7-a/arm_scu.c | 4 ++++
arch/arm/src/armv7-a/barriers.h | 6 ++++--
3 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/arch/arm/src/armv7-a/arm_head.S b/arch/arm/src/armv7-a/arm_head.S
index fe41d4eb9d..0ce90ec415 100644
--- a/arch/arm/src/armv7-a/arm_head.S
+++ b/arch/arm/src/armv7-a/arm_head.S
@@ -172,6 +172,32 @@
.type __start, #function
__start:
+#if defined(CONFIG_SMP) && CONFIG_SMP_NCPUS > 1
+ /* Get cpuindex, cpu0 continue boot, others wait event from cpu0 */
+
+ mrc CP15_MPIDR(r0)
+ and r0, r0, #0x3
+ cmp r0, #0
+ beq __cpu0_start
+ wfe
+ cmp r0, #1
+ beq __cpu1_start
+# if CONFIG_SMP_NCPUS > 2
+ cmp r0, #2
+ beq __cpu2_start
+# endif
+# if CONFIG_SMP_NCPUS > 3
+ cmp r0, #3
+ beq __cpu3_start
+# endif
+# if CONFIG_SMP_NCPUS > 4
+ cmp r0, #4
+ beq __cpu4_start
+# endif
+
+__cpu0_start:
+#endif
+
/* Make sure that we are in SYS mode with IRQs and FIQs disabled */
cpsid if, #PSR_MODE_SYS
diff --git a/arch/arm/src/armv7-a/arm_scu.c b/arch/arm/src/armv7-a/arm_scu.c
index 3d717d9bc8..6c5b0198a4 100644
--- a/arch/arm/src/armv7-a/arm_scu.c
+++ b/arch/arm/src/armv7-a/arm_scu.c
@@ -80,6 +80,10 @@ void arm_enable_smp(int cpu)
regval = getreg32(SCU_CTRL);
regval |= SCU_CTRL_ENABLE;
putreg32(regval, SCU_CTRL);
+
+ /* Initialize done, kick other cpus which waiting on __start */
+
+ ARM_SEV();
}
/* Actions for other CPUs */
diff --git a/arch/arm/src/armv7-a/barriers.h b/arch/arm/src/armv7-a/barriers.h
index b3a242c52f..e8b5d94f93 100644
--- a/arch/arm/src/armv7-a/barriers.h
+++ b/arch/arm/src/armv7-a/barriers.h
@@ -34,11 +34,13 @@
#define arm_isb(n) __asm__ __volatile__ ("isb " #n : : : "memory")
#define arm_dsb(n) __asm__ __volatile__ ("dsb " #n : : : "memory")
#define arm_dmb(n) __asm__ __volatile__ ("dmb " #n : : : "memory")
-#define arm_nop(n) __asm__ __volatile__ ("nop\n")
+#define arm_nop() __asm__ __volatile__ ("nop\n")
+#define arm_sev() __asm__ __volatile__ ("sev\n")
#define ARM_DSB() arm_dsb(15)
#define ARM_ISB() arm_isb(15)
#define ARM_DMB() arm_dmb(15)
-#define ARM_NOP() arm_nop(15)
+#define ARM_NOP() arm_nop()
+#define ARM_SEV() arm_sev()
#endif /* __ARCH_ARM_SRC_ARMV7_A_BARRIERS_H */