| 1 | // SPDX-License-Identifier: GPL-2.0 |
|---|---|
| 2 | /* |
| 3 | * Copyright (C) 2021, Qing Zhang <zhangqing@loongson.cn> |
| 4 | * Loongson-2K1000 reset support |
| 5 | */ |
| 6 | |
| 7 | #include <linux/of_address.h> |
| 8 | #include <linux/pm.h> |
| 9 | #include <asm/reboot.h> |
| 10 | |
| 11 | #define PM1_STS 0x0c /* Power Management 1 Status Register */ |
| 12 | #define PM1_CNT 0x14 /* Power Management 1 Control Register */ |
| 13 | #define RST_CNT 0x30 /* Reset Control Register */ |
| 14 | |
| 15 | static void __iomem *base; |
| 16 | |
| 17 | static void ls2k_restart(char *command) |
| 18 | { |
| 19 | writel(val: 0x1, addr: base + RST_CNT); |
| 20 | } |
| 21 | |
| 22 | static void ls2k_poweroff(void) |
| 23 | { |
| 24 | /* Clear */ |
| 25 | writel(val: (readl(addr: base + PM1_STS) & 0xffffffff), addr: base + PM1_STS); |
| 26 | /* Sleep Enable | Soft Off*/ |
| 27 | writel(GENMASK(12, 10) | BIT(13), addr: base + PM1_CNT); |
| 28 | } |
| 29 | |
| 30 | static int ls2k_reset_init(void) |
| 31 | { |
| 32 | struct device_node *np; |
| 33 | |
| 34 | np = of_find_compatible_node(NULL, NULL, compat: "loongson,ls2k-pm"); |
| 35 | if (!np) { |
| 36 | pr_info("Failed to get PM node\n"); |
| 37 | return -ENODEV; |
| 38 | } |
| 39 | |
| 40 | base = of_iomap(node: np, index: 0); |
| 41 | of_node_put(node: np); |
| 42 | if (!base) { |
| 43 | pr_info("Failed to map PM register base address\n"); |
| 44 | return -ENOMEM; |
| 45 | } |
| 46 | |
| 47 | _machine_restart = ls2k_restart; |
| 48 | pm_power_off = ls2k_poweroff; |
| 49 | |
| 50 | return 0; |
| 51 | } |
| 52 | |
| 53 | arch_initcall(ls2k_reset_init); |
| 54 |