linux/arch/arm/mach-mvebu/pmsu.c

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/*
* Power Management Service Unit(PMSU) support for Armada 370/XP platforms.
*
* Copyright (C) 2012 Marvell
*
* Yehuda Yitschak <yehuday@marvell.com>
* Gregory Clement <gregory.clement@free-electrons.com>
* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*
* The Armada 370 and Armada XP SOCs have a power management service
* unit which is responsible for powering down and waking up CPUs and
* other SOC units
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/smp.h>
#include <asm/smp_plat.h>
static void __iomem *pmsu_mp_base;
static void __iomem *pmsu_reset_base;
#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x24)
#define PMSU_RESET_CTL_OFFSET(cpu) (cpu * 0x8)
static struct of_device_id of_pmsu_table[] = {
{.compatible = "marvell,armada-370-xp-pmsu"},
{ /* end of list */ },
};
#ifdef CONFIG_SMP
int armada_xp_boot_cpu(unsigned int cpu_id, void *boot_addr)
{
int reg, hw_cpu;
if (!pmsu_mp_base || !pmsu_reset_base) {
pr_warn("Can't boot CPU. PMSU is uninitialized\n");
return 1;
}
hw_cpu = cpu_logical_map(cpu_id);
writel(virt_to_phys(boot_addr), pmsu_mp_base +
PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
/* Release CPU from reset by clearing reset bit*/
reg = readl(pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu));
reg &= (~0x1);
writel(reg, pmsu_reset_base + PMSU_RESET_CTL_OFFSET(hw_cpu));
return 0;
}
#endif
int __init armada_370_xp_pmsu_init(void)
{
struct device_node *np;
np = of_find_matching_node(NULL, of_pmsu_table);
if (np) {
pr_info("Initializing Power Management Service Unit\n");
pmsu_mp_base = of_iomap(np, 0);
pmsu_reset_base = of_iomap(np, 1);
of_node_put(np);
}
return 0;
}
early_initcall(armada_370_xp_pmsu_init);