// SPDX-License-Identifier: (GPL-2.0) /* * oxnas SoC reset driver * based on: * Microsemi MIPS SoC reset driver * and ox820_assert_system_reset() written by Ma Hajun * * Copyright (c) 2013 Ma Hajun * Copyright (c) 2017 Microsemi Corporation * Copyright (c) 2020 Daniel Golle */ #include #include #include #include #include #include #include /* bit numbers of reset control register */ #define OX820_SYS_CTRL_RST_SCU 0 #define OX820_SYS_CTRL_RST_COPRO 1 #define OX820_SYS_CTRL_RST_ARM0 2 #define OX820_SYS_CTRL_RST_ARM1 3 #define OX820_SYS_CTRL_RST_USBHS 4 #define OX820_SYS_CTRL_RST_USBHSPHYA 5 #define OX820_SYS_CTRL_RST_MACA 6 #define OX820_SYS_CTRL_RST_MAC OX820_SYS_CTRL_RST_MACA #define OX820_SYS_CTRL_RST_PCIEA 7 #define OX820_SYS_CTRL_RST_SGDMA 8 #define OX820_SYS_CTRL_RST_CIPHER 9 #define OX820_SYS_CTRL_RST_DDR 10 #define OX820_SYS_CTRL_RST_SATA 11 #define OX820_SYS_CTRL_RST_SATA_LINK 12 #define OX820_SYS_CTRL_RST_SATA_PHY 13 #define OX820_SYS_CTRL_RST_PCIEPHY 14 #define OX820_SYS_CTRL_RST_STATIC 15 #define OX820_SYS_CTRL_RST_GPIO 16 #define OX820_SYS_CTRL_RST_UART1 17 #define OX820_SYS_CTRL_RST_UART2 18 #define OX820_SYS_CTRL_RST_MISC 19 #define OX820_SYS_CTRL_RST_I2S 20 #define OX820_SYS_CTRL_RST_SD 21 #define OX820_SYS_CTRL_RST_MACB 22 #define OX820_SYS_CTRL_RST_PCIEB 23 #define OX820_SYS_CTRL_RST_VIDEO 24 #define OX820_SYS_CTRL_RST_DDR_PHY 25 #define OX820_SYS_CTRL_RST_USBHSPHYB 26 #define OX820_SYS_CTRL_RST_USBDEV 27 #define OX820_SYS_CTRL_RST_ARMDBG 29 #define OX820_SYS_CTRL_RST_PLLA 30 #define OX820_SYS_CTRL_RST_PLLB 31 /* bit numbers of clock control register */ #define OX820_SYS_CTRL_CLK_COPRO 0 #define OX820_SYS_CTRL_CLK_DMA 1 #define OX820_SYS_CTRL_CLK_CIPHER 2 #define OX820_SYS_CTRL_CLK_SD 3 #define OX820_SYS_CTRL_CLK_SATA 4 #define OX820_SYS_CTRL_CLK_I2S 5 #define OX820_SYS_CTRL_CLK_USBHS 6 #define OX820_SYS_CTRL_CLK_MACA 7 #define OX820_SYS_CTRL_CLK_MAC OX820_SYS_CTRL_CLK_MACA #define OX820_SYS_CTRL_CLK_PCIEA 8 #define OX820_SYS_CTRL_CLK_STATIC 9 #define OX820_SYS_CTRL_CLK_MACB 10 #define OX820_SYS_CTRL_CLK_PCIEB 11 #define OX820_SYS_CTRL_CLK_REF600 12 #define OX820_SYS_CTRL_CLK_USBDEV 13 #define OX820_SYS_CTRL_CLK_DDR 14 #define OX820_SYS_CTRL_CLK_DDRPHY 15 #define OX820_SYS_CTRL_CLK_DDRCK 16 /* Regmap offsets */ #define OX820_CLK_SET_REGOFFSET 0x2c #define OX820_CLK_CLR_REGOFFSET 0x30 #define OX820_RST_SET_REGOFFSET 0x34 #define OX820_RST_CLR_REGOFFSET 0x38 #define OX820_SECONDARY_SEL_REGOFFSET 0x14 #define OX820_TERTIARY_SEL_REGOFFSET 0x8c #define OX820_QUATERNARY_SEL_REGOFFSET 0x94 #define OX820_DEBUG_SEL_REGOFFSET 0x9c #define OX820_ALTERNATIVE_SEL_REGOFFSET 0xa4 #define OX820_PULLUP_SEL_REGOFFSET 0xac #define OX820_SEC_SECONDARY_SEL_REGOFFSET 0x100014 #define OX820_SEC_TERTIARY_SEL_REGOFFSET 0x10008c #define OX820_SEC_QUATERNARY_SEL_REGOFFSET 0x100094 #define OX820_SEC_DEBUG_SEL_REGOFFSET 0x10009c #define OX820_SEC_ALTERNATIVE_SEL_REGOFFSET 0x1000a4 #define OX820_SEC_PULLUP_SEL_REGOFFSET 0x1000ac struct oxnas_restart_context { struct regmap *sys_ctrl; struct notifier_block restart_handler; }; static int ox820_restart_handle(struct notifier_block *this, unsigned long mode, void *cmd) { struct oxnas_restart_context *ctx = container_of(this, struct oxnas_restart_context, restart_handler); u32 value; /* * Assert reset to cores as per power on defaults * Don't touch the DDR interface as things will come to an impromptu * stop NB Possibly should be asserting reset for PLLB, but there are * timing concerns here according to the docs */ value = BIT(OX820_SYS_CTRL_RST_COPRO) | BIT(OX820_SYS_CTRL_RST_USBHS) | BIT(OX820_SYS_CTRL_RST_USBHSPHYA) | BIT(OX820_SYS_CTRL_RST_MACA) | BIT(OX820_SYS_CTRL_RST_PCIEA) | BIT(OX820_SYS_CTRL_RST_SGDMA) | BIT(OX820_SYS_CTRL_RST_CIPHER) | BIT(OX820_SYS_CTRL_RST_SATA) | BIT(OX820_SYS_CTRL_RST_SATA_LINK) | BIT(OX820_SYS_CTRL_RST_SATA_PHY) | BIT(OX820_SYS_CTRL_RST_PCIEPHY) | BIT(OX820_SYS_CTRL_RST_STATIC) | BIT(OX820_SYS_CTRL_RST_UART1) | BIT(OX820_SYS_CTRL_RST_UART2) | BIT(OX820_SYS_CTRL_RST_MISC) | BIT(OX820_SYS_CTRL_RST_I2S) | BIT(OX820_SYS_CTRL_RST_SD) | BIT(OX820_SYS_CTRL_RST_MACB) | BIT(OX820_SYS_CTRL_RST_PCIEB) | BIT(OX820_SYS_CTRL_RST_VIDEO) | BIT(OX820_SYS_CTRL_RST_USBHSPHYB) | BIT(OX820_SYS_CTRL_RST_USBDEV); regmap_write(ctx->sys_ctrl, OX820_RST_SET_REGOFFSET, value); /* Release reset to cores as per power on defaults */ regmap_write(ctx->sys_ctrl, OX820_RST_CLR_REGOFFSET, BIT(OX820_SYS_CTRL_RST_GPIO)); /* * Disable clocks to cores as per power-on defaults - must leave DDR * related clocks enabled otherwise we'll stop rather abruptly. */ value = BIT(OX820_SYS_CTRL_CLK_COPRO) | BIT(OX820_SYS_CTRL_CLK_DMA) | BIT(OX820_SYS_CTRL_CLK_CIPHER) | BIT(OX820_SYS_CTRL_CLK_SD) | BIT(OX820_SYS_CTRL_CLK_SATA) | BIT(OX820_SYS_CTRL_CLK_I2S) | BIT(OX820_SYS_CTRL_CLK_USBHS) | BIT(OX820_SYS_CTRL_CLK_MAC) | BIT(OX820_SYS_CTRL_CLK_PCIEA) | BIT(OX820_SYS_CTRL_CLK_STATIC) | BIT(OX820_SYS_CTRL_CLK_MACB) | BIT(OX820_SYS_CTRL_CLK_PCIEB) | BIT(OX820_SYS_CTRL_CLK_REF600) | BIT(OX820_SYS_CTRL_CLK_USBDEV); regmap_write(ctx->sys_ctrl, OX820_CLK_CLR_REGOFFSET, value); /* Enable clocks to cores as per power-on defaults */ /* Set sys-control pin mux'ing as per power-on defaults */ regmap_write(ctx->sys_ctrl, OX820_SECONDARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_TERTIARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_QUATERNARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_DEBUG_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_ALTERNATIVE_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_PULLUP_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_SECONDARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_TERTIARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_QUATERNARY_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_DEBUG_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_ALTERNATIVE_SEL_REGOFFSET, 0); regmap_write(ctx->sys_ctrl, OX820_SEC_PULLUP_SEL_REGOFFSET, 0); /* * No need to save any state, as the ROM loader can determine whether * reset is due to power cycling or programatic action, just hit the * (self-clearing) CPU reset bit of the block reset register */ value = BIT(OX820_SYS_CTRL_RST_SCU) | BIT(OX820_SYS_CTRL_RST_ARM0) | BIT(OX820_SYS_CTRL_RST_ARM1); regmap_write(ctx->sys_ctrl, OX820_RST_SET_REGOFFSET, value); pr_emerg("Unable to restart system\n"); return NOTIFY_DONE; } static int ox820_restart_probe(struct platform_device *pdev) { struct oxnas_restart_context *ctx; struct regmap *sys_ctrl; struct device *dev = &pdev->dev; int err = 0; sys_ctrl = syscon_node_to_regmap(pdev->dev.of_node); if (IS_ERR(sys_ctrl)) return PTR_ERR(sys_ctrl); ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); if (!ctx) return -ENOMEM; ctx->sys_ctrl = sys_ctrl; ctx->restart_handler.notifier_call = ox820_restart_handle; ctx->restart_handler.priority = 192; err = register_restart_handler(&ctx->restart_handler); if (err) dev_err(dev, "can't register restart notifier (err=%d)\n", err); return err; } static const struct of_device_id ox820_restart_of_match[] = { { .compatible = "oxsemi,ox820-sys-ctrl" }, {} }; static struct platform_driver ox820_restart_driver = { .probe = ox820_restart_probe, .driver = { .name = "ox820-chip-reset", .of_match_table = ox820_restart_of_match, }, }; builtin_platform_driver(ox820_restart_driver);