linux/arch/arm/mach-mvebu/pmsu.c
Gregory CLEMENT f713c7e742 ARM: mvebu: Allow to power down L2 cache controller in idle mode
This commit adds a function which adjusts the PMSU configuration to
automatically power down the L2 and coherency fabric when we enter a
certain idle state.

This feature is part of the Power Management Service Unit of the
Armada 370 and Armada XP SoCs.

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Link: https://lkml.kernel.org/r/1397488214-20685-8-git-send-email-gregory.clement@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
2014-05-08 16:18:56 +00:00

114 lines
2.8 KiB
C

/*
* 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
*/
#define pr_fmt(fmt) "mvebu-pmsu: " fmt
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/smp.h>
#include <linux/resource.h>
#include <asm/smp_plat.h>
#include "common.h"
#include "pmsu.h"
static void __iomem *pmsu_mp_base;
#define PMSU_BASE_OFFSET 0x100
#define PMSU_REG_SIZE 0x1000
/* PMSU MP registers */
#define PMSU_BOOT_ADDR_REDIRECT_OFFSET(cpu) ((cpu * 0x100) + 0x124)
/* PMSU fabric registers */
#define L2C_NFABRIC_PM_CTL 0x4
#define L2C_NFABRIC_PM_CTL_PWR_DOWN BIT(20)
static struct of_device_id of_pmsu_table[] = {
{ .compatible = "marvell,armada-370-pmsu", },
{ .compatible = "marvell,armada-370-xp-pmsu", },
{ .compatible = "marvell,armada-380-pmsu", },
{ /* end of list */ },
};
void mvebu_pmsu_set_cpu_boot_addr(int hw_cpu, void *boot_addr)
{
writel(virt_to_phys(boot_addr), pmsu_mp_base +
PMSU_BOOT_ADDR_REDIRECT_OFFSET(hw_cpu));
}
static int __init armada_370_xp_pmsu_init(void)
{
struct device_node *np;
struct resource res;
int ret = 0;
np = of_find_matching_node(NULL, of_pmsu_table);
if (!np)
return 0;
pr_info("Initializing Power Management Service Unit\n");
if (of_address_to_resource(np, 0, &res)) {
pr_err("unable to get resource\n");
ret = -ENOENT;
goto out;
}
if (of_device_is_compatible(np, "marvell,armada-370-xp-pmsu")) {
pr_warn(FW_WARN "deprecated pmsu binding\n");
res.start = res.start - PMSU_BASE_OFFSET;
res.end = res.start + PMSU_REG_SIZE - 1;
}
if (!request_mem_region(res.start, resource_size(&res),
np->full_name)) {
pr_err("unable to request region\n");
ret = -EBUSY;
goto out;
}
pmsu_mp_base = ioremap(res.start, resource_size(&res));
if (!pmsu_mp_base) {
pr_err("unable to map registers\n");
release_mem_region(res.start, resource_size(&res));
ret = -ENOMEM;
goto out;
}
out:
of_node_put(np);
return ret;
}
static void armada_370_xp_pmsu_enable_l2_powerdown_onidle(void)
{
u32 reg;
if (pmsu_mp_base == NULL)
return;
/* Enable L2 & Fabric powerdown in Deep-Idle mode - Fabric */
reg = readl(pmsu_mp_base + L2C_NFABRIC_PM_CTL);
reg |= L2C_NFABRIC_PM_CTL_PWR_DOWN;
writel(reg, pmsu_mp_base + L2C_NFABRIC_PM_CTL);
}
early_initcall(armada_370_xp_pmsu_init);