| 1 | // SPDX-License-Identifier: GPL-2.0-only |
|---|---|
| 2 | /* |
| 3 | * Power Management driver for Marvell Kirkwood SoCs |
| 4 | * |
| 5 | * Copyright (C) 2013 Ezequiel Garcia <ezequiel@free-electrons.com> |
| 6 | * Copyright (C) 2010 Simon Guinot <sguinot@lacie.com> |
| 7 | */ |
| 8 | |
| 9 | #include <linux/kernel.h> |
| 10 | #include <linux/suspend.h> |
| 11 | #include <linux/io.h> |
| 12 | #include "kirkwood.h" |
| 13 | #include "kirkwood-pm.h" |
| 14 | |
| 15 | static void __iomem *ddr_operation_base; |
| 16 | static void __iomem *memory_pm_ctrl; |
| 17 | |
| 18 | static void kirkwood_low_power(void) |
| 19 | { |
| 20 | u32 mem_pm_ctrl; |
| 21 | |
| 22 | mem_pm_ctrl = readl(addr: memory_pm_ctrl); |
| 23 | |
| 24 | /* Set peripherals to low-power mode */ |
| 25 | writel_relaxed(~0, memory_pm_ctrl); |
| 26 | |
| 27 | /* Set DDR in self-refresh */ |
| 28 | writel_relaxed(0x7, ddr_operation_base); |
| 29 | |
| 30 | /* |
| 31 | * Set CPU in wait-for-interrupt state. |
| 32 | * This disables the CPU core clocks, |
| 33 | * the array clocks, and also the L2 controller. |
| 34 | */ |
| 35 | cpu_do_idle(); |
| 36 | |
| 37 | writel_relaxed(mem_pm_ctrl, memory_pm_ctrl); |
| 38 | } |
| 39 | |
| 40 | static int kirkwood_suspend_enter(suspend_state_t state) |
| 41 | { |
| 42 | switch (state) { |
| 43 | case PM_SUSPEND_STANDBY: |
| 44 | kirkwood_low_power(); |
| 45 | break; |
| 46 | default: |
| 47 | return -EINVAL; |
| 48 | } |
| 49 | return 0; |
| 50 | } |
| 51 | |
| 52 | static int kirkwood_pm_valid_standby(suspend_state_t state) |
| 53 | { |
| 54 | return state == PM_SUSPEND_STANDBY; |
| 55 | } |
| 56 | |
| 57 | static const struct platform_suspend_ops kirkwood_suspend_ops = { |
| 58 | .enter = kirkwood_suspend_enter, |
| 59 | .valid = kirkwood_pm_valid_standby, |
| 60 | }; |
| 61 | |
| 62 | void __init kirkwood_pm_init(void) |
| 63 | { |
| 64 | ddr_operation_base = ioremap(DDR_OPERATION_BASE, size: 4); |
| 65 | memory_pm_ctrl = ioremap(MEMORY_PM_CTRL_PHYS, size: 4); |
| 66 | |
| 67 | suspend_set_ops(ops: &kirkwood_suspend_ops); |
| 68 | } |
| 69 |