/*
* Copyright (C) 2002 ARM Ltd.
* Copyright (C) 2008 STMicroelctronics.
* Copyright (C) 2009 ST-Ericsson.
* Author: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
*
* This file is based on arm realview platform
*
* 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/init.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <asm/cacheflush.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include "db8500-regs.h"
/* Magic triggers in backup RAM */
#define UX500_CPU1_JUMPADDR_OFFSET 0x1FF4
#define UX500_CPU1_WAKEMAGIC_OFFSET 0x1FF0
static void __iomem *backupram;
static void __init ux500_smp_prepare_cpus(unsigned int max_cpus)
{
struct device_node *np;
static void __iomem *scu_base;
unsigned int ncores;
int i;
np = of_find_compatible_node(NULL, NULL, "ste,dbx500-backupram");
if (!np) {
pr_err("No backupram base address\n");
return;
}
backupram = of_iomap(np, 0);
of_node_put(np);
if (!backupram) {
pr_err("No backupram remap\n");
return;
}
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
if (!np) {
pr_err("No SCU base address\n");
return;
}
scu_base = of_iomap(np, 0);
of_node_put(np);
if (!scu_base) {
pr_err("No SCU remap\n");
return;
}
scu_enable(scu_base);
ncores = scu_get_core_count(scu_base);
for (i = 0; i < ncores; i++)
set_cpu_possible(i, true);
iounmap(scu_base);
}
static int ux500_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
/*
* write the address of secondary startup into the backup ram register
* at offset 0x1FF4, then write the magic number 0xA1FEED01 to the
* backup ram register at offset 0x1FF0, which is what boot rom code
* is waiting for. This will wake up the secondary core from WFE.
*/
writel(__pa_symbol(secondary_startup),
backupram + UX500_CPU1_JUMPADDR_OFFSET);
writel(0xA1FEED01,
backupram + UX500_CPU1_WAKEMAGIC_OFFSET);
/* make sure write buffer is drained */
mb();
arch_send_wakeup_ipi_mask(cpumask_of(cpu));
return 0;
}
#ifdef CONFIG_HOTPLUG_CPU
void ux500_cpu_die(unsigned int cpu)
{
wfi();
}
#endif
static const struct smp_operations ux500_smp_ops __initconst = {
.smp_prepare_cpus = ux500_smp_prepare_cpus,
.smp_boot_secondary = ux500_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_die = ux500_cpu_die,
#endif
};
CPU_METHOD_OF_DECLARE(ux500_smp, "ste,dbx500-smp", &ux500_smp_ops);
