nuttx/arch/arm/src/armv7-a/arm_scu.c
ligd 078a0486f5 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 <liguiding1@xiaomi.com>
2022-09-28 10:33:13 +09:00

126 lines
3.7 KiB
C

/****************************************************************************
* arch/arm/src/armv7-a/arm_scu.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include "arm_internal.h"
#include "cp15_cacheops.h"
#include "barriers.h"
#include "sctlr.h"
#include "scu.h"
#include "cp15.h"
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: arm_enable_smp
*
* Description:
* Enable the SCU and make certain that current CPU is participating in
* the SMP cache coherency.
*
* Assumption:
* Called early in the CPU start-up. No special critical sections are
* needed if only CPU-private registers are modified.
*
****************************************************************************/
void arm_enable_smp(int cpu)
{
uint32_t regval;
/* Handle actions unique to CPU0 which comes up first */
if (cpu == 0)
{
/* Invalidate the SCU duplicate tags for all processors */
putreg32((SCU_INVALIDATE_ALL_WAYS << SCU_INVALIDATE_CPU0_SHIFT) |
(SCU_INVALIDATE_ALL_WAYS << SCU_INVALIDATE_CPU1_SHIFT) |
(SCU_INVALIDATE_ALL_WAYS << SCU_INVALIDATE_CPU2_SHIFT) |
(SCU_INVALIDATE_ALL_WAYS << SCU_INVALIDATE_CPU3_SHIFT),
SCU_INVALIDATE);
/* Invalidate CPUn L1 data cache so that is will we be reloaded from
* coherent L2.
*/
cp15_invalidate_dcache_all();
ARM_DSB();
/* Invalidate the L2C-310 -- Missing logic. */
/* Enable the SCU */
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 */
else
{
/* Invalidate CPUn L1 data cache so that is will we be reloaded from
* coherent L2.
*/
cp15_dcache_op_level(0, CP15_CACHE_INVALIDATE);
ARM_DSB();
/* Wait for the SCU to be enabled by the primary processor -- should
* not be necessary.
*/
}
/* Enable the data cache, set the SMP mode with ACTLR.SMP=1.
*
* SMP - Sgnals if the Cortex-A9 processor is taking part in coherency
* or not.
*
* Cortex-A9 also needs ACTLR.FW=1
*
* FW - Cache and TLB maintenance broadcast.
*/
regval = CP15_GET(ACTLR);
regval |= ACTLR_SMP;
#ifdef CONFIG_ARCH_CORTEXA9
regval |= ACTLR_FW;
#endif
CP15_SET(ACTLR, regval);
regval = CP15_GET(SCTLR);
regval |= SCTLR_C | SCTLR_I | SCTLR_M;
CP15_SET(SCTLR, regval);
}