105 lines
2.2 KiB
C
105 lines
2.2 KiB
C
|
/*
|
||
|
|
* Copyright (C) 2012-2013 Xilinx
|
||
|
|
*
|
||
|
|
* based on linux/arch/arm/mach-realview/hotplug.c
|
||
|
|
*
|
||
|
|
* Copyright (C) 2002 ARM Ltd.
|
||
|
|
* All Rights Reserved
|
||
|
|
*
|
||
|
|
* This program is free software; you can redistribute it and/or modify
|
||
|
|
* it under the terms of the GNU General Public License version 2 as
|
||
|
|
* published by the Free Software Foundation.
|
||
|
|
*/
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <linux/errno.h>
|
||
|
|
#include <linux/smp.h>
|
||
|
|
|
||
|
|
#include <asm/cacheflush.h>
|
||
|
|
#include <asm/cp15.h>
|
||
|
|
#include "common.h"
|
||
|
|
|
||
|
|
static inline void zynq_cpu_enter_lowpower(void)
|
||
|
|
{
|
||
|
|
unsigned int v;
|
||
|
|
|
||
|
|
flush_cache_all();
|
||
|
|
asm volatile(
|
||
|
|
" mcr p15, 0, %1, c7, c5, 0\n"
|
||
|
|
" dsb\n"
|
||
|
|
/*
|
||
|
|
* Turn off coherency
|
||
|
|
*/
|
||
|
|
" mrc p15, 0, %0, c1, c0, 1\n"
|
||
|
|
" bic %0, %0, #0x40\n"
|
||
|
|
" mcr p15, 0, %0, c1, c0, 1\n"
|
||
|
|
" mrc p15, 0, %0, c1, c0, 0\n"
|
||
|
|
" bic %0, %0, %2\n"
|
||
|
|
" mcr p15, 0, %0, c1, c0, 0\n"
|
||
|
|
: "=&r" (v)
|
||
|
|
: "r" (0), "Ir" (CR_C)
|
||
|
|
: "cc");
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void zynq_cpu_leave_lowpower(void)
|
||
|
|
{
|
||
|
|
unsigned int v;
|
||
|
|
|
||
|
|
asm volatile(
|
||
|
|
" mrc p15, 0, %0, c1, c0, 0\n"
|
||
|
|
" orr %0, %0, %1\n"
|
||
|
|
" mcr p15, 0, %0, c1, c0, 0\n"
|
||
|
|
" mrc p15, 0, %0, c1, c0, 1\n"
|
||
|
|
" orr %0, %0, #0x40\n"
|
||
|
|
" mcr p15, 0, %0, c1, c0, 1\n"
|
||
|
|
: "=&r" (v)
|
||
|
|
: "Ir" (CR_C)
|
||
|
|
: "cc");
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void zynq_platform_do_lowpower(unsigned int cpu, int *spurious)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* there is no power-control hardware on this platform, so all
|
||
|
|
* we can do is put the core into WFI; this is safe as the calling
|
||
|
|
* code will have already disabled interrupts
|
||
|
|
*/
|
||
|
|
for (;;) {
|
||
|
|
dsb();
|
||
|
|
wfi();
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Getting here, means that we have come out of WFI without
|
||
|
|
* having been woken up - this shouldn't happen
|
||
|
|
*
|
||
|
|
* Just note it happening - when we're woken, we can report
|
||
|
|
* its occurrence.
|
||
|
|
*/
|
||
|
|
(*spurious)++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/*
|
||
|
|
* platform-specific code to shutdown a CPU
|
||
|
|
*
|
||
|
|
* Called with IRQs disabled
|
||
|
|
*/
|
||
|
|
void zynq_platform_cpu_die(unsigned int cpu)
|
||
|
|
{
|
||
|
|
int spurious = 0;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* we're ready for shutdown now, so do it
|
||
|
|
*/
|
||
|
|
zynq_cpu_enter_lowpower();
|
||
|
|
zynq_platform_do_lowpower(cpu, &spurious);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* bring this CPU back into the world of cache
|
||
|
|
* coherency, and then restore interrupts
|
||
|
|
*/
|
||
|
|
zynq_cpu_leave_lowpower();
|
||
|
|
|
||
|
|
if (spurious)
|
||
|
|
pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
|
||
|
|
}
|