linux-stable/arch/arm/mach-shmobile/platsmp-scu.c
Geert Uytterhoeven d4a617c9bb ARM: shmobile: Stop using __raw_*() I/O accessors
There is no reason to keep on using the __raw_{read,write}l() I/O
accessors in Renesas ARM platform code.  Switch to using the plain
{read,write}l() I/O accessors, to have a chance that this works on
big-endian.

Suggested-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20201117142447.2205664-1-geert+renesas@glider.be
2020-11-23 09:54:59 +01:00

90 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* SMP support for SoCs with SCU covered by mach-shmobile
*
* Copyright (C) 2013 Magnus Damm
*/
#include <linux/cpu.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/smp.h>
#include <asm/cacheflush.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include "common.h"
static phys_addr_t shmobile_scu_base_phys;
static void __iomem *shmobile_scu_base;
static int shmobile_scu_cpu_prepare(unsigned int cpu)
{
/* For this particular CPU register SCU SMP boot vector */
shmobile_smp_hook(cpu, __pa_symbol(shmobile_boot_scu),
shmobile_scu_base_phys);
return 0;
}
void __init shmobile_smp_scu_prepare_cpus(phys_addr_t scu_base_phys,
unsigned int max_cpus)
{
/* install boot code shared by all CPUs */
shmobile_boot_fn = __pa_symbol(shmobile_smp_boot);
/* enable SCU and cache coherency on booting CPU */
shmobile_scu_base_phys = scu_base_phys;
shmobile_scu_base = ioremap(scu_base_phys, PAGE_SIZE);
scu_enable(shmobile_scu_base);
scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL);
/* Use CPU notifier for reset vector control */
cpuhp_setup_state_nocalls(CPUHP_ARM_SHMOBILE_SCU_PREPARE,
"arm/shmobile-scu:prepare",
shmobile_scu_cpu_prepare, NULL);
}
#ifdef CONFIG_HOTPLUG_CPU
void shmobile_smp_scu_cpu_die(unsigned int cpu)
{
/* For this particular CPU deregister boot vector */
shmobile_smp_hook(cpu, 0, 0);
dsb();
flush_cache_all();
/* disable cache coherency */
scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF);
/* jump to shared mach-shmobile sleep / reset code */
shmobile_smp_sleep();
}
static int shmobile_smp_scu_psr_core_disabled(int cpu)
{
unsigned long mask = SCU_PM_POWEROFF << (cpu * 8);
if ((readl(shmobile_scu_base + 8) & mask) == mask)
return 1;
return 0;
}
int shmobile_smp_scu_cpu_kill(unsigned int cpu)
{
int k;
/* this function is running on another CPU than the offline target,
* here we need wait for shutdown code in platform_cpu_die() to
* finish before asking SoC-specific code to power off the CPU core.
*/
for (k = 0; k < 1000; k++) {
if (shmobile_smp_scu_psr_core_disabled(cpu))
return 1;
mdelay(1);
}
return 0;
}
#endif