/*
* Copyright (C) 2014 Marvell Technology Group Ltd.
*
* Antoine Ténart <antoine.tenart@free-electrons.com>
*
* 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/io.h>
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <asm/cacheflush.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
/*
* There are two reset registers, one with self-clearing (SC)
* reset and one with non-self-clearing reset (NON_SC).
*/
#define CPU_RESET_SC 0x00
#define CPU_RESET_NON_SC 0x20
#define RESET_VECT 0x00
#define SW_RESET_ADDR 0x94
extern u32 boot_inst;
static void __iomem *cpu_ctrl;
static inline void berlin_perform_reset_cpu(unsigned int cpu)
{
u32 val;
val = readl(cpu_ctrl + CPU_RESET_NON_SC);
val &= ~BIT(cpu_logical_map(cpu));
writel(val, cpu_ctrl + CPU_RESET_NON_SC);
val |= BIT(cpu_logical_map(cpu));
writel(val, cpu_ctrl + CPU_RESET_NON_SC);
}
static int berlin_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
if (!cpu_ctrl)
return -EFAULT;
/*
* Reset the CPU, making it to execute the instruction in the reset
* exception vector.
*/
berlin_perform_reset_cpu(cpu);
return 0;
}
static void __init berlin_smp_prepare_cpus(unsigned int max_cpus)
{
struct device_node *np;
void __iomem *scu_base;
void __iomem *vectors_base;
np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
scu_base = of_iomap(np, 0);
of_node_put(np);
if (!scu_base)
return;
np = of_find_compatible_node(NULL, NULL, "marvell,berlin-cpu-ctrl");
cpu_ctrl = of_iomap(np, 0);
of_node_put(np);
if (!cpu_ctrl)
goto unmap_scu;
vectors_base = ioremap(CONFIG_VECTORS_BASE, SZ_32K);
if (!vectors_base)
goto unmap_scu;
scu_enable(scu_base);
flush_cache_all();
/*
* Write the first instruction the CPU will execute after being reset
* in the reset exception vector.
*/
writel(boot_inst, vectors_base + RESET_VECT);
/*
* Write the secondary startup address into the SW reset address
* vector. This is used by boot_inst.
*/
writel(virt_to_phys(secondary_startup), vectors_base + SW_RESET_ADDR);
iounmap(vectors_base);
unmap_scu:
iounmap(scu_base);
}
static struct smp_operations berlin_smp_ops __initdata = {
.smp_prepare_cpus = berlin_smp_prepare_cpus,
.smp_boot_secondary = berlin_boot_secondary,
};
CPU_METHOD_OF_DECLARE(berlin_smp, "marvell,berlin-smp", &berlin_smp_ops);
