Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

power: reset: introduce oxnas-restart

Add reboot handler for Oxford OX820 chips as reboot currenly hangs on
those boards. Code is based on ox820_assert_system_reset() found in
https://github.com/kref/linux-oxnas.git in
arch/arm/mach-oxnas/mach-ox820.c line 181.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

authored by

Daniel Golle and committed by
Sebastian Reichel
0edb259c 21b01cc8

+242
+1
MAINTAINERS
··· 2163 2163 S: Maintained 2164 2164 F: arch/arm/boot/dts/ox8*.dts* 2165 2165 F: arch/arm/mach-oxnas/ 2166 + F: drivers/power/reset/oxnas-restart.c 2166 2167 N: oxnas 2167 2168 2168 2169 ARM/PALM TREO SUPPORT
+7
drivers/power/reset/Kconfig
··· 123 123 help 124 124 This driver supports restart for Microsemi Ocelot SoC. 125 125 126 + config POWER_RESET_OXNAS 127 + bool "OXNAS SoC restart driver" 128 + depends on ARCH_OXNAS 129 + default MACH_OX820 130 + help 131 + Restart support for OXNAS/PLXTECH OX820 SoC. 132 + 126 133 config POWER_RESET_PIIX4_POWEROFF 127 134 tristate "Intel PIIX4 power-off driver" 128 135 depends on PCI
+1
drivers/power/reset/Makefile
··· 12 12 obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o 13 13 obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o 14 14 obj-$(CONFIG_POWER_RESET_MT6323) += mt6323-poweroff.o 15 + obj-$(CONFIG_POWER_RESET_OXNAS) += oxnas-restart.o 15 16 obj-$(CONFIG_POWER_RESET_QCOM_PON) += qcom-pon.o 16 17 obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o 17 18 obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o
+233
drivers/power/reset/oxnas-restart.c
··· 1 + // SPDX-License-Identifier: (GPL-2.0) 2 + /* 3 + * oxnas SoC reset driver 4 + * based on: 5 + * Microsemi MIPS SoC reset driver 6 + * and ox820_assert_system_reset() written by Ma Hajun <mahaijuns@gmail.com> 7 + * 8 + * Copyright (c) 2013 Ma Hajun <mahaijuns@gmail.com> 9 + * Copyright (c) 2017 Microsemi Corporation 10 + * Copyright (c) 2020 Daniel Golle <daniel@makrotopia.org> 11 + */ 12 + #include <linux/delay.h> 13 + #include <linux/io.h> 14 + #include <linux/notifier.h> 15 + #include <linux/mfd/syscon.h> 16 + #include <linux/of_address.h> 17 + #include <linux/of_device.h> 18 + #include <linux/platform_device.h> 19 + #include <linux/reboot.h> 20 + #include <linux/regmap.h> 21 + 22 + /* bit numbers of reset control register */ 23 + #define OX820_SYS_CTRL_RST_SCU 0 24 + #define OX820_SYS_CTRL_RST_COPRO 1 25 + #define OX820_SYS_CTRL_RST_ARM0 2 26 + #define OX820_SYS_CTRL_RST_ARM1 3 27 + #define OX820_SYS_CTRL_RST_USBHS 4 28 + #define OX820_SYS_CTRL_RST_USBHSPHYA 5 29 + #define OX820_SYS_CTRL_RST_MACA 6 30 + #define OX820_SYS_CTRL_RST_MAC OX820_SYS_CTRL_RST_MACA 31 + #define OX820_SYS_CTRL_RST_PCIEA 7 32 + #define OX820_SYS_CTRL_RST_SGDMA 8 33 + #define OX820_SYS_CTRL_RST_CIPHER 9 34 + #define OX820_SYS_CTRL_RST_DDR 10 35 + #define OX820_SYS_CTRL_RST_SATA 11 36 + #define OX820_SYS_CTRL_RST_SATA_LINK 12 37 + #define OX820_SYS_CTRL_RST_SATA_PHY 13 38 + #define OX820_SYS_CTRL_RST_PCIEPHY 14 39 + #define OX820_SYS_CTRL_RST_STATIC 15 40 + #define OX820_SYS_CTRL_RST_GPIO 16 41 + #define OX820_SYS_CTRL_RST_UART1 17 42 + #define OX820_SYS_CTRL_RST_UART2 18 43 + #define OX820_SYS_CTRL_RST_MISC 19 44 + #define OX820_SYS_CTRL_RST_I2S 20 45 + #define OX820_SYS_CTRL_RST_SD 21 46 + #define OX820_SYS_CTRL_RST_MACB 22 47 + #define OX820_SYS_CTRL_RST_PCIEB 23 48 + #define OX820_SYS_CTRL_RST_VIDEO 24 49 + #define OX820_SYS_CTRL_RST_DDR_PHY 25 50 + #define OX820_SYS_CTRL_RST_USBHSPHYB 26 51 + #define OX820_SYS_CTRL_RST_USBDEV 27 52 + #define OX820_SYS_CTRL_RST_ARMDBG 29 53 + #define OX820_SYS_CTRL_RST_PLLA 30 54 + #define OX820_SYS_CTRL_RST_PLLB 31 55 + 56 + /* bit numbers of clock control register */ 57 + #define OX820_SYS_CTRL_CLK_COPRO 0 58 + #define OX820_SYS_CTRL_CLK_DMA 1 59 + #define OX820_SYS_CTRL_CLK_CIPHER 2 60 + #define OX820_SYS_CTRL_CLK_SD 3 61 + #define OX820_SYS_CTRL_CLK_SATA 4 62 + #define OX820_SYS_CTRL_CLK_I2S 5 63 + #define OX820_SYS_CTRL_CLK_USBHS 6 64 + #define OX820_SYS_CTRL_CLK_MACA 7 65 + #define OX820_SYS_CTRL_CLK_MAC OX820_SYS_CTRL_CLK_MACA 66 + #define OX820_SYS_CTRL_CLK_PCIEA 8 67 + #define OX820_SYS_CTRL_CLK_STATIC 9 68 + #define OX820_SYS_CTRL_CLK_MACB 10 69 + #define OX820_SYS_CTRL_CLK_PCIEB 11 70 + #define OX820_SYS_CTRL_CLK_REF600 12 71 + #define OX820_SYS_CTRL_CLK_USBDEV 13 72 + #define OX820_SYS_CTRL_CLK_DDR 14 73 + #define OX820_SYS_CTRL_CLK_DDRPHY 15 74 + #define OX820_SYS_CTRL_CLK_DDRCK 16 75 + 76 + /* Regmap offsets */ 77 + #define OX820_CLK_SET_REGOFFSET 0x2c 78 + #define OX820_CLK_CLR_REGOFFSET 0x30 79 + #define OX820_RST_SET_REGOFFSET 0x34 80 + #define OX820_RST_CLR_REGOFFSET 0x38 81 + #define OX820_SECONDARY_SEL_REGOFFSET 0x14 82 + #define OX820_TERTIARY_SEL_REGOFFSET 0x8c 83 + #define OX820_QUATERNARY_SEL_REGOFFSET 0x94 84 + #define OX820_DEBUG_SEL_REGOFFSET 0x9c 85 + #define OX820_ALTERNATIVE_SEL_REGOFFSET 0xa4 86 + #define OX820_PULLUP_SEL_REGOFFSET 0xac 87 + #define OX820_SEC_SECONDARY_SEL_REGOFFSET 0x100014 88 + #define OX820_SEC_TERTIARY_SEL_REGOFFSET 0x10008c 89 + #define OX820_SEC_QUATERNARY_SEL_REGOFFSET 0x100094 90 + #define OX820_SEC_DEBUG_SEL_REGOFFSET 0x10009c 91 + #define OX820_SEC_ALTERNATIVE_SEL_REGOFFSET 0x1000a4 92 + #define OX820_SEC_PULLUP_SEL_REGOFFSET 0x1000ac 93 + 94 + struct oxnas_restart_context { 95 + struct regmap *sys_ctrl; 96 + struct notifier_block restart_handler; 97 + }; 98 + 99 + static int ox820_restart_handle(struct notifier_block *this, 100 + unsigned long mode, void *cmd) 101 + { 102 + struct oxnas_restart_context *ctx = container_of(this, struct 103 + oxnas_restart_context, 104 + restart_handler); 105 + u32 value; 106 + 107 + /* 108 + * Assert reset to cores as per power on defaults 109 + * Don't touch the DDR interface as things will come to an impromptu 110 + * stop NB Possibly should be asserting reset for PLLB, but there are 111 + * timing concerns here according to the docs 112 + */ 113 + value = BIT(OX820_SYS_CTRL_RST_COPRO) | 114 + BIT(OX820_SYS_CTRL_RST_USBHS) | 115 + BIT(OX820_SYS_CTRL_RST_USBHSPHYA) | 116 + BIT(OX820_SYS_CTRL_RST_MACA) | 117 + BIT(OX820_SYS_CTRL_RST_PCIEA) | 118 + BIT(OX820_SYS_CTRL_RST_SGDMA) | 119 + BIT(OX820_SYS_CTRL_RST_CIPHER) | 120 + BIT(OX820_SYS_CTRL_RST_SATA) | 121 + BIT(OX820_SYS_CTRL_RST_SATA_LINK) | 122 + BIT(OX820_SYS_CTRL_RST_SATA_PHY) | 123 + BIT(OX820_SYS_CTRL_RST_PCIEPHY) | 124 + BIT(OX820_SYS_CTRL_RST_STATIC) | 125 + BIT(OX820_SYS_CTRL_RST_UART1) | 126 + BIT(OX820_SYS_CTRL_RST_UART2) | 127 + BIT(OX820_SYS_CTRL_RST_MISC) | 128 + BIT(OX820_SYS_CTRL_RST_I2S) | 129 + BIT(OX820_SYS_CTRL_RST_SD) | 130 + BIT(OX820_SYS_CTRL_RST_MACB) | 131 + BIT(OX820_SYS_CTRL_RST_PCIEB) | 132 + BIT(OX820_SYS_CTRL_RST_VIDEO) | 133 + BIT(OX820_SYS_CTRL_RST_USBHSPHYB) | 134 + BIT(OX820_SYS_CTRL_RST_USBDEV); 135 + 136 + regmap_write(ctx->sys_ctrl, OX820_RST_SET_REGOFFSET, value); 137 + 138 + /* Release reset to cores as per power on defaults */ 139 + regmap_write(ctx->sys_ctrl, OX820_RST_CLR_REGOFFSET, 140 + BIT(OX820_SYS_CTRL_RST_GPIO)); 141 + 142 + /* 143 + * Disable clocks to cores as per power-on defaults - must leave DDR 144 + * related clocks enabled otherwise we'll stop rather abruptly. 145 + */ 146 + value = BIT(OX820_SYS_CTRL_CLK_COPRO) | 147 + BIT(OX820_SYS_CTRL_CLK_DMA) | 148 + BIT(OX820_SYS_CTRL_CLK_CIPHER) | 149 + BIT(OX820_SYS_CTRL_CLK_SD) | 150 + BIT(OX820_SYS_CTRL_CLK_SATA) | 151 + BIT(OX820_SYS_CTRL_CLK_I2S) | 152 + BIT(OX820_SYS_CTRL_CLK_USBHS) | 153 + BIT(OX820_SYS_CTRL_CLK_MAC) | 154 + BIT(OX820_SYS_CTRL_CLK_PCIEA) | 155 + BIT(OX820_SYS_CTRL_CLK_STATIC) | 156 + BIT(OX820_SYS_CTRL_CLK_MACB) | 157 + BIT(OX820_SYS_CTRL_CLK_PCIEB) | 158 + BIT(OX820_SYS_CTRL_CLK_REF600) | 159 + BIT(OX820_SYS_CTRL_CLK_USBDEV); 160 + 161 + regmap_write(ctx->sys_ctrl, OX820_CLK_CLR_REGOFFSET, value); 162 + 163 + /* Enable clocks to cores as per power-on defaults */ 164 + 165 + /* Set sys-control pin mux'ing as per power-on defaults */ 166 + regmap_write(ctx->sys_ctrl, OX820_SECONDARY_SEL_REGOFFSET, 0); 167 + regmap_write(ctx->sys_ctrl, OX820_TERTIARY_SEL_REGOFFSET, 0); 168 + regmap_write(ctx->sys_ctrl, OX820_QUATERNARY_SEL_REGOFFSET, 0); 169 + regmap_write(ctx->sys_ctrl, OX820_DEBUG_SEL_REGOFFSET, 0); 170 + regmap_write(ctx->sys_ctrl, OX820_ALTERNATIVE_SEL_REGOFFSET, 0); 171 + regmap_write(ctx->sys_ctrl, OX820_PULLUP_SEL_REGOFFSET, 0); 172 + 173 + regmap_write(ctx->sys_ctrl, OX820_SEC_SECONDARY_SEL_REGOFFSET, 0); 174 + regmap_write(ctx->sys_ctrl, OX820_SEC_TERTIARY_SEL_REGOFFSET, 0); 175 + regmap_write(ctx->sys_ctrl, OX820_SEC_QUATERNARY_SEL_REGOFFSET, 0); 176 + regmap_write(ctx->sys_ctrl, OX820_SEC_DEBUG_SEL_REGOFFSET, 0); 177 + regmap_write(ctx->sys_ctrl, OX820_SEC_ALTERNATIVE_SEL_REGOFFSET, 0); 178 + regmap_write(ctx->sys_ctrl, OX820_SEC_PULLUP_SEL_REGOFFSET, 0); 179 + 180 + /* 181 + * No need to save any state, as the ROM loader can determine whether 182 + * reset is due to power cycling or programatic action, just hit the 183 + * (self-clearing) CPU reset bit of the block reset register 184 + */ 185 + value = 186 + BIT(OX820_SYS_CTRL_RST_SCU) | 187 + BIT(OX820_SYS_CTRL_RST_ARM0) | 188 + BIT(OX820_SYS_CTRL_RST_ARM1); 189 + 190 + regmap_write(ctx->sys_ctrl, OX820_RST_SET_REGOFFSET, value); 191 + 192 + pr_emerg("Unable to restart system\n"); 193 + return NOTIFY_DONE; 194 + } 195 + 196 + static int ox820_restart_probe(struct platform_device *pdev) 197 + { 198 + struct oxnas_restart_context *ctx; 199 + struct regmap *sys_ctrl; 200 + struct device *dev = &pdev->dev; 201 + int err = 0; 202 + 203 + sys_ctrl = syscon_node_to_regmap(pdev->dev.of_node); 204 + if (IS_ERR(sys_ctrl)) 205 + return PTR_ERR(sys_ctrl); 206 + 207 + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); 208 + if (!ctx) 209 + return -ENOMEM; 210 + 211 + ctx->sys_ctrl = sys_ctrl; 212 + ctx->restart_handler.notifier_call = ox820_restart_handle; 213 + ctx->restart_handler.priority = 192; 214 + err = register_restart_handler(&ctx->restart_handler); 215 + if (err) 216 + dev_err(dev, "can't register restart notifier (err=%d)\n", err); 217 + 218 + return err; 219 + } 220 + 221 + static const struct of_device_id ox820_restart_of_match[] = { 222 + { .compatible = "oxsemi,ox820-sys-ctrl" }, 223 + {} 224 + }; 225 + 226 + static struct platform_driver ox820_restart_driver = { 227 + .probe = ox820_restart_probe, 228 + .driver = { 229 + .name = "ox820-chip-reset", 230 + .of_match_table = ox820_restart_of_match, 231 + }, 232 + }; 233 + builtin_platform_driver(ox820_restart_driver);