Staging
v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: f55532a0c0b8bb6148f4e07853b876ef73bc69ca authored by Linus Torvalds on 26 March 2016, 23:03:24 UTC
Linux 4.6-rc1
Linux 4.6-rc1
Tip revision: f55532a
pm.c
/*
* arch/arm/mach-socfpga/pm.c
*
* Copyright (C) 2014-2015 Altera Corporation. All rights reserved.
*
* with code from pm-imx6.c
* Copyright 2011-2014 Freescale Semiconductor, Inc.
* Copyright 2011 Linaro Ltd.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/bitops.h>
#include <linux/genalloc.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/of_platform.h>
#include <linux/suspend.h>
#include <asm/suspend.h>
#include <asm/fncpy.h>
#include "core.h"
/* Pointer to function copied to ocram */
static u32 (*socfpga_sdram_self_refresh_in_ocram)(u32 sdr_base);
static int socfpga_setup_ocram_self_refresh(void)
{
struct platform_device *pdev;
phys_addr_t ocram_pbase;
struct device_node *np;
struct gen_pool *ocram_pool;
unsigned long ocram_base;
void __iomem *suspend_ocram_base;
int ret = 0;
np = of_find_compatible_node(NULL, NULL, "mmio-sram");
if (!np) {
pr_err("%s: Unable to find mmio-sram in dtb\n", __func__);
return -ENODEV;
}
pdev = of_find_device_by_node(np);
if (!pdev) {
pr_warn("%s: failed to find ocram device!\n", __func__);
ret = -ENODEV;
goto put_node;
}
ocram_pool = gen_pool_get(&pdev->dev, NULL);
if (!ocram_pool) {
pr_warn("%s: ocram pool unavailable!\n", __func__);
ret = -ENODEV;
goto put_node;
}
ocram_base = gen_pool_alloc(ocram_pool, socfpga_sdram_self_refresh_sz);
if (!ocram_base) {
pr_warn("%s: unable to alloc ocram!\n", __func__);
ret = -ENOMEM;
goto put_node;
}
ocram_pbase = gen_pool_virt_to_phys(ocram_pool, ocram_base);
suspend_ocram_base = __arm_ioremap_exec(ocram_pbase,
socfpga_sdram_self_refresh_sz,
false);
if (!suspend_ocram_base) {
pr_warn("%s: __arm_ioremap_exec failed!\n", __func__);
ret = -ENOMEM;
goto put_node;
}
/* Copy the code that puts DDR in self refresh to ocram */
socfpga_sdram_self_refresh_in_ocram =
(void *)fncpy(suspend_ocram_base,
&socfpga_sdram_self_refresh,
socfpga_sdram_self_refresh_sz);
WARN(!socfpga_sdram_self_refresh_in_ocram,
"could not copy function to ocram");
if (!socfpga_sdram_self_refresh_in_ocram)
ret = -EFAULT;
put_node:
of_node_put(np);
return ret;
}
static int socfpga_pm_suspend(unsigned long arg)
{
u32 ret;
if (!sdr_ctl_base_addr)
return -EFAULT;
ret = socfpga_sdram_self_refresh_in_ocram((u32)sdr_ctl_base_addr);
pr_debug("%s self-refresh loops request=%d exit=%d\n", __func__,
ret & 0xffff, (ret >> 16) & 0xffff);
return 0;
}
static int socfpga_pm_enter(suspend_state_t state)
{
switch (state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
outer_disable();
cpu_suspend(0, socfpga_pm_suspend);
outer_resume();
break;
default:
return -EINVAL;
}
return 0;
}
static const struct platform_suspend_ops socfpga_pm_ops = {
.valid = suspend_valid_only_mem,
.enter = socfpga_pm_enter,
};
static int __init socfpga_pm_init(void)
{
int ret;
ret = socfpga_setup_ocram_self_refresh();
if (ret)
return ret;
suspend_set_ops(&socfpga_pm_ops);
pr_info("SoCFPGA initialized for DDR self-refresh during suspend.\n");
return 0;
}
arch_initcall(socfpga_pm_init);