diff options
Diffstat (limited to 'drivers/power/reset/ocelot-reset.c')
| -rw-r--r-- | drivers/power/reset/ocelot-reset.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/power/reset/ocelot-reset.c b/drivers/power/reset/ocelot-reset.c new file mode 100644 index 0000000000..56be64decf --- /dev/null +++ b/drivers/power/reset/ocelot-reset.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: (GPL-2.0 OR MIT) +/* + * Microsemi MIPS SoC reset driver + * + * License: Dual MIT/GPL + * Copyright (c) 2017 Microsemi Corporation + */ +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/notifier.h> +#include <linux/mod_devicetable.h> +#include <linux/mfd/syscon.h> +#include <linux/platform_device.h> +#include <linux/property.h> +#include <linux/reboot.h> +#include <linux/regmap.h> + +struct reset_props { + const char *syscon; + u32 protect_reg; + u32 vcore_protect; + u32 if_si_owner_bit; +}; + +struct ocelot_reset_context { + void __iomem *base; + struct regmap *cpu_ctrl; + const struct reset_props *props; + struct notifier_block restart_handler; +}; + +#define BIT_OFF_INVALID 32 + +#define SOFT_CHIP_RST BIT(0) + +#define ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24 +#define IF_SI_OWNER_MASK GENMASK(1, 0) +#define IF_SI_OWNER_SISL 0 +#define IF_SI_OWNER_SIBM 1 +#define IF_SI_OWNER_SIMC 2 + +static int ocelot_restart_handle(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + struct ocelot_reset_context *ctx = container_of(this, struct + ocelot_reset_context, + restart_handler); + u32 if_si_owner_bit = ctx->props->if_si_owner_bit; + + /* Make sure the core is not protected from reset */ + regmap_update_bits(ctx->cpu_ctrl, ctx->props->protect_reg, + ctx->props->vcore_protect, 0); + + /* Make the SI back to boot mode */ + if (if_si_owner_bit != BIT_OFF_INVALID) + regmap_update_bits(ctx->cpu_ctrl, + ICPU_CFG_CPU_SYSTEM_CTRL_GENERAL_CTRL, + IF_SI_OWNER_MASK << if_si_owner_bit, + IF_SI_OWNER_SIBM << if_si_owner_bit); + + pr_emerg("Resetting SoC\n"); + + writel(SOFT_CHIP_RST, ctx->base); + + pr_emerg("Unable to restart system\n"); + return NOTIFY_DONE; +} + +static int ocelot_reset_probe(struct platform_device *pdev) +{ + struct ocelot_reset_context *ctx; + struct device *dev = &pdev->dev; + int err; + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(ctx->base)) + return PTR_ERR(ctx->base); + + ctx->props = device_get_match_data(dev); + + ctx->cpu_ctrl = syscon_regmap_lookup_by_compatible(ctx->props->syscon); + if (IS_ERR(ctx->cpu_ctrl)) { + dev_err(dev, "No syscon map: %s\n", ctx->props->syscon); + return PTR_ERR(ctx->cpu_ctrl); + } + + ctx->restart_handler.notifier_call = ocelot_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 reset_props reset_props_jaguar2 = { + .syscon = "mscc,ocelot-cpu-syscon", + .protect_reg = 0x20, + .vcore_protect = BIT(2), + .if_si_owner_bit = 6, +}; + +static const struct reset_props reset_props_luton = { + .syscon = "mscc,ocelot-cpu-syscon", + .protect_reg = 0x20, + .vcore_protect = BIT(2), + .if_si_owner_bit = BIT_OFF_INVALID, /* n/a */ +}; + +static const struct reset_props reset_props_ocelot = { + .syscon = "mscc,ocelot-cpu-syscon", + .protect_reg = 0x20, + .vcore_protect = BIT(2), + .if_si_owner_bit = 4, +}; + +static const struct reset_props reset_props_sparx5 = { + .syscon = "microchip,sparx5-cpu-syscon", + .protect_reg = 0x84, + .vcore_protect = BIT(10), + .if_si_owner_bit = 6, +}; + +static const struct of_device_id ocelot_reset_of_match[] = { + { + .compatible = "mscc,jaguar2-chip-reset", + .data = &reset_props_jaguar2 + }, { + .compatible = "mscc,luton-chip-reset", + .data = &reset_props_luton + }, { + .compatible = "mscc,ocelot-chip-reset", + .data = &reset_props_ocelot + }, { + .compatible = "microchip,sparx5-chip-reset", + .data = &reset_props_sparx5 + }, + { /*sentinel*/ } +}; + +static struct platform_driver ocelot_reset_driver = { + .probe = ocelot_reset_probe, + .driver = { + .name = "ocelot-chip-reset", + .of_match_table = ocelot_reset_of_match, + }, +}; +builtin_platform_driver(ocelot_reset_driver); |