Driver to handle reset block in prcm of AM43x, AM335x SoC's. There are three reset's that can be handled by this reset driver - gfx, m3 and pruss. Of this only gfx has been handled here, adding support for the remaining only require adding array entries with details of pruss and m3. Signed-off-by: Afzal Mohammed <afzal@xxxxxx> --- drivers/reset/Kconfig | 14 ++++ drivers/reset/Makefile | 1 + drivers/reset/amx3_reset.c | 157 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 172 insertions(+) create mode 100644 drivers/reset/amx3_reset.c diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index c9d04f7..2af81b9 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -11,3 +11,17 @@ menuconfig RESET_CONTROLLER via GPIOs or SoC-internal reset controller modules. If unsure, say no. + +if RESET_CONTROLLER + +config RESET_AMX3 + bool "AMx3 reset controller" + help + Reset controller support for AM43x/AM335x SoC's + + Reset controller found in TI's AM series of SoC's like + AM335x and AM43x + + If unsure, say no. + +endif diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 1e2d83f..b8c1afe 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -1 +1,2 @@ obj-$(CONFIG_RESET_CONTROLLER) += core.o +obj-$(CONFIG_RESET_AMX3) += amx3_reset.o diff --git a/drivers/reset/amx3_reset.c b/drivers/reset/amx3_reset.c new file mode 100644 index 0000000..4e476a5 --- /dev/null +++ b/drivers/reset/amx3_reset.c @@ -0,0 +1,157 @@ +/* + * PRCM reset driver for AM335x & AM43x SoC's + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#include <linux/device.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/reset.h> +#include <linux/reset-controller.h> +#include <linux/platform_device.h> +#include <linux/io.h> + +#define DRIVER_NAME "amx3_reset" + +struct amx3_reset_reg_data { + u32 rstctrl_offs; + u32 rstst_offs; + u8 rstctrl_bit; + u8 rstst_bit; +}; + +struct amx3_reset_data { + struct amx3_reset_reg_data *reg_data; + u8 nr_resets; +}; + +static void __iomem *reg_base; +static const struct amx3_reset_data *amx3_reset_data; + +static struct amx3_reset_reg_data am335x_reset_reg_data[] = { + { + .rstctrl_offs = 0x1104, + .rstst_offs = 0x1114, + .rstctrl_bit = 0, + .rstst_bit = 0, + }, +}; + +static struct amx3_reset_data am335x_reset_data = { + .reg_data = am335x_reset_reg_data, + .nr_resets = ARRAY_SIZE(am335x_reset_reg_data), +}; + +static struct amx3_reset_reg_data am43x_reset_reg_data[] = { + { + .rstctrl_offs = 0x410, + .rstst_offs = 0x414, + .rstctrl_bit = 0, + .rstst_bit = 0, + }, +}; + +static struct amx3_reset_data am43x_reset_data = { + .reg_data = am43x_reset_reg_data, + .nr_resets = ARRAY_SIZE(am43x_reset_reg_data), +}; + +static int amx3_reset_clear_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + void __iomem *reg = amx3_reset_data->reg_data[id].rstst_offs + reg_base; + u8 bit = amx3_reset_data->reg_data[id].rstst_bit; + u32 val = readl(reg); + + val &= ~(1 << bit); + val |= 1 << bit; + writel(val, reg); + return 0; +} + +static int amx3_reset_is_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + void __iomem *reg = amx3_reset_data->reg_data[id].rstst_offs + reg_base; + u8 bit = amx3_reset_data->reg_data[id].rstst_bit; + u32 val = readl(reg); + + val &= (1 << bit); + return !!val; +} + +static int amx3_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + void __iomem *reg = amx3_reset_data->reg_data[id].rstctrl_offs + + reg_base; + u8 bit = amx3_reset_data->reg_data[id].rstctrl_bit; + u32 val = readl(reg); + + val &= ~(1 << bit); + writel(val, reg); + return 0; +} + +static struct reset_control_ops amx3_reset_ops = { + .deassert = amx3_reset_deassert, + .is_reset = amx3_reset_is_reset, + .clear_reset = amx3_reset_clear_reset, +}; + +static struct reset_controller_dev amx3_reset_controller = { + .ops = &amx3_reset_ops, +}; + +static const struct of_device_id amx3_reset_of_match[] = { + { .compatible = "ti,am3352-prcm", .data = &am335x_reset_data,}, + { .compatible = "ti,am4372-prcm", .data = &am43x_reset_data,}, + {}, +}; + +static int amx3_reset_probe(struct platform_device *pdev) +{ + struct resource *res; + const struct of_device_id *id; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reg_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(reg_base)) + return PTR_ERR(reg_base); + + amx3_reset_controller.of_node = pdev->dev.of_node; + id = of_match_device(amx3_reset_of_match, &pdev->dev); + amx3_reset_data = id->data; + amx3_reset_controller.nr_resets = amx3_reset_data->nr_resets; + + reset_controller_register(&amx3_reset_controller); + + return 0; +} + +static int amx3_reset_remove(struct platform_device *pdev) +{ + reset_controller_unregister(&amx3_reset_controller); + + return 0; +} + +static struct platform_driver amx3_reset_driver = { + .probe = amx3_reset_probe, + .remove = amx3_reset_remove, + .driver = { + .name = DRIVER_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(amx3_reset_of_match), + }, +}; +module_platform_driver(amx3_reset_driver); + +MODULE_DESCRIPTION("PRCM reset driver for TI AM43x/AM335x SoC's"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DRIVER_NAME); -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html