diff options
Diffstat (limited to 'kernel/arch/arm/mach-mvebu/kirkwood-pm.c')
-rw-r--r-- | kernel/arch/arm/mach-mvebu/kirkwood-pm.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-mvebu/kirkwood-pm.c b/kernel/arch/arm/mach-mvebu/kirkwood-pm.c new file mode 100644 index 000000000..cbb816f21 --- /dev/null +++ b/kernel/arch/arm/mach-mvebu/kirkwood-pm.c @@ -0,0 +1,76 @@ +/* + * Power Management driver for Marvell Kirkwood SoCs + * + * Copyright (C) 2013 Ezequiel Garcia <ezequiel@free-electrons.com> + * Copyright (C) 2010 Simon Guinot <sguinot@lacie.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 of the License. + * + * This program is distributed in the hope that 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. + */ + +#include <linux/kernel.h> +#include <linux/suspend.h> +#include <linux/io.h> +#include "kirkwood.h" + +static void __iomem *ddr_operation_base; +static void __iomem *memory_pm_ctrl; + +static void kirkwood_low_power(void) +{ + u32 mem_pm_ctrl; + + mem_pm_ctrl = readl(memory_pm_ctrl); + + /* Set peripherals to low-power mode */ + writel_relaxed(~0, memory_pm_ctrl); + + /* Set DDR in self-refresh */ + writel_relaxed(0x7, ddr_operation_base); + + /* + * Set CPU in wait-for-interrupt state. + * This disables the CPU core clocks, + * the array clocks, and also the L2 controller. + */ + cpu_do_idle(); + + writel_relaxed(mem_pm_ctrl, memory_pm_ctrl); +} + +static int kirkwood_suspend_enter(suspend_state_t state) +{ + switch (state) { + case PM_SUSPEND_STANDBY: + kirkwood_low_power(); + break; + default: + return -EINVAL; + } + return 0; +} + +static int kirkwood_pm_valid_standby(suspend_state_t state) +{ + return state == PM_SUSPEND_STANDBY; +} + +static const struct platform_suspend_ops kirkwood_suspend_ops = { + .enter = kirkwood_suspend_enter, + .valid = kirkwood_pm_valid_standby, +}; + +int __init kirkwood_pm_init(void) +{ + ddr_operation_base = ioremap(DDR_OPERATION_BASE, 4); + memory_pm_ctrl = ioremap(MEMORY_PM_CTRL_PHYS, 4); + + suspend_set_ops(&kirkwood_suspend_ops); + return 0; +} |