Add reset driver for Sunplus SP7021 SoC. Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx> Signed-off-by: Qin Jian <qinjian@xxxxxxxxxxx> --- MAINTAINERS | 1 + drivers/reset/Kconfig | 9 +++ drivers/reset/Makefile | 1 + drivers/reset/reset-sunplus.c | 130 ++++++++++++++++++++++++++++++++++ 4 files changed, 141 insertions(+) create mode 100644 drivers/reset/reset-sunplus.c diff --git a/MAINTAINERS b/MAINTAINERS index a8be86b25..26066f199 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -2745,6 +2745,7 @@ S: Maintained W: https://sunplus-tibbo.atlassian.net/wiki/spaces/doc/overview F: Documentation/devicetree/bindings/arm/sunplus,sp7021.yaml F: Documentation/devicetree/bindings/reset/sunplus,reset.yaml +F: drivers/reset/reset-sunplus.c F: include/dt-bindings/reset/sp-sp7021.h ARM/Synaptics SoC support diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index 6f8ba0ddc..36825787e 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -231,6 +231,15 @@ config RESET_STARFIVE_JH7100 help This enables the reset controller driver for the StarFive JH7100 SoC. +config RESET_SUNPLUS + bool "Sunplus SoCs Reset Driver" if COMPILE_TEST + default ARCH_SUNPLUS + help + This enables the reset driver support for Sunplus SoCs. + The reset lines that can be asserted and deasserted by toggling bits + in a contiguous, exclusive register space. The register is HIWORD_MASKED, + which means each register hold 16 reset lines. + config RESET_SUNXI bool "Allwinner SoCs Reset Driver" if COMPILE_TEST && !ARCH_SUNXI default ARCH_SUNXI diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index bd0a97be1..cadc46d3e 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -30,6 +30,7 @@ obj-$(CONFIG_RESET_SCMI) += reset-scmi.o obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o obj-$(CONFIG_RESET_STARFIVE_JH7100) += reset-starfive-jh7100.o +obj-$(CONFIG_RESET_SUNPLUS) += reset-sunplus.o obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o diff --git a/drivers/reset/reset-sunplus.c b/drivers/reset/reset-sunplus.c new file mode 100644 index 000000000..113b36b57 --- /dev/null +++ b/drivers/reset/reset-sunplus.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +/* + * SP7021 reset driver + * + * Copyright (C) Sunplus Technology Co., Ltd. + * All rights reserved. + */ + +#include <linux/io.h> +#include <linux/init.h> +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/reboot.h> + +/* HIWORD_MASK_REG BITS */ +#define BITS_PER_HWM_REG 16 + +struct sp_reset { + struct reset_controller_dev rcdev; + struct notifier_block notifier; + void __iomem *base; +}; + +static inline struct sp_reset *to_sp_reset(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct sp_reset, rcdev); +} + +static int sp_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct sp_reset *reset = to_sp_reset(rcdev); + int index = id / BITS_PER_HWM_REG; + int shift = id % BITS_PER_HWM_REG; + u32 val; + + val = (1 << (16 + shift)) | (assert << shift); + writel(val, reset->base + (index * 4)); + + return 0; +} + +static int sp_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return sp_reset_update(rcdev, id, true); +} + +static int sp_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return sp_reset_update(rcdev, id, false); +} + +static int sp_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct sp_reset *reset = to_sp_reset(rcdev); + int index = id / BITS_PER_HWM_REG; + int shift = id % BITS_PER_HWM_REG; + u32 reg; + + reg = readl(reset->base + (index * 4)); + + return !!(reg & BIT(shift)); +} + +static const struct reset_control_ops sp_reset_ops = { + .assert = sp_reset_assert, + .deassert = sp_reset_deassert, + .status = sp_reset_status, +}; + +static int sp_restart(struct notifier_block *nb, unsigned long mode, + void *cmd) +{ + struct sp_reset *reset = container_of(nb, struct sp_reset, notifier); + + sp_reset_assert(&reset->rcdev, 0); + sp_reset_deassert(&reset->rcdev, 0); + + return NOTIFY_DONE; +} + +static int sp_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct sp_reset *reset; + struct resource *res; + int ret; + + reset = devm_kzalloc(dev, sizeof(*reset), GFP_KERNEL); + if (!reset) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reset->base = devm_ioremap_resource(dev, res); + if (IS_ERR(reset->base)) + return PTR_ERR(reset->base); + + reset->rcdev.ops = &sp_reset_ops; + reset->rcdev.owner = THIS_MODULE; + reset->rcdev.of_node = dev->of_node; + reset->rcdev.nr_resets = resource_size(res) / 4 * BITS_PER_HWM_REG; + + ret = devm_reset_controller_register(dev, &reset->rcdev); + if (ret) + return ret; + + reset->notifier.notifier_call = sp_restart; + reset->notifier.priority = 192; + + return register_restart_handler(&reset->notifier); +} + +static const struct of_device_id sp_reset_dt_ids[] = { + {.compatible = "sunplus,sp7021-reset",}, + { /* sentinel */ }, +}; + +static struct platform_driver sp_reset_driver = { + .probe = sp_reset_probe, + .driver = { + .name = "sunplus-reset", + .of_match_table = sp_reset_dt_ids, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(sp_reset_driver); -- 2.33.1
