From 8fd06aeb8a6d1fa25185b7a3adc96a54d44251a9 Mon Sep 17 00:00:00 2001 From: Sam Protsenko Date: Wed, 10 Jan 2024 21:09:01 -0600 Subject: [PATCH] soc: samsung: Add Exynos PMU driver Add basic Power Management Unit (PMU) driver for Exynos SoCs. For now it's only capable of changing UART path in PMU, which is needed for E850-96 board. The driver's structure resembles the exynos-pmu driver from Linux kernel, and although it's very basic and slim at the moment, it can be easily extended in future if the need arises. UCLASS_NOP is used, as there are no benefits in using more elaborate classes like UCLASS_MISC in this case. The DM_FLAG_PROBE_AFTER_BIND flag is added in bind function, as the probe function must be always called for this driver. Signed-off-by: Sam Protsenko Reviewed-by: Chanho Park Signed-off-by: Minkyu Kang --- drivers/soc/samsung/Kconfig | 10 +++ drivers/soc/samsung/Makefile | 1 + drivers/soc/samsung/exynos-pmu.c | 102 +++++++++++++++++++++++++++++++ 3 files changed, 113 insertions(+) create mode 100644 drivers/soc/samsung/exynos-pmu.c diff --git a/drivers/soc/samsung/Kconfig b/drivers/soc/samsung/Kconfig index ffb87fe793..737b7ca8cd 100644 --- a/drivers/soc/samsung/Kconfig +++ b/drivers/soc/samsung/Kconfig @@ -5,6 +5,16 @@ menuconfig SOC_SAMSUNG if SOC_SAMSUNG +config EXYNOS_PMU + bool "Exynos PMU controller driver" + depends on ARCH_EXYNOS + select REGMAP + select SYSCON + help + Enable support for system controller configuration driver. It allows + one to configure system controller registers (e.g. some register in + PMU syscon) by providing register's offset, mask and value. + config EXYNOS_USI bool "Exynos USI (Universal Serial Interface) driver" depends on ARCH_EXYNOS diff --git a/drivers/soc/samsung/Makefile b/drivers/soc/samsung/Makefile index 833ac073fb..0eb3ed8353 100644 --- a/drivers/soc/samsung/Makefile +++ b/drivers/soc/samsung/Makefile @@ -1,3 +1,4 @@ # SPDX-License-Identifier: GPL-2.0+ +obj-$(CONFIG_EXYNOS_PMU) += exynos-pmu.o obj-$(CONFIG_EXYNOS_USI) += exynos-usi.o diff --git a/drivers/soc/samsung/exynos-pmu.c b/drivers/soc/samsung/exynos-pmu.c new file mode 100644 index 0000000000..233ad4a908 --- /dev/null +++ b/drivers/soc/samsung/exynos-pmu.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2023 Linaro Ltd. + * Author: Sam Protsenko + * + * Exynos PMU (Power Management Unit) driver. + */ + +#include +#include +#include +#include +#include +#include + +#define EXYNOS850_UART_IO_SHARE_CTRL 0x0760 +#define SEL_RXD_AP_UART_SHIFT 16 +#define SEL_RXD_AP_UART_MASK GENMASK(17, 16) +#define SEL_TXD_GPIO_1_SHIFT 20 +#define SEL_TXD_GPIO_1_MASK GENMASK(21, 20) +#define RXD_GPIO_1 0x3 +#define TXD_AP_UART 0x0 + +struct exynos_pmu { + struct udevice *dev; + const struct exynos_pmu_data *pmu_data; + struct regmap *regmap; +}; + +struct exynos_pmu_data { + int (*pmu_init)(struct exynos_pmu *priv); +}; + +static int exynos850_pmu_init(struct exynos_pmu *priv) +{ + ofnode node; + bool uart_debug_1; + unsigned int offset, mask, value; + + node = dev_ofnode(priv->dev); + uart_debug_1 = ofnode_read_bool(node, "samsung,uart-debug-1"); + if (!uart_debug_1) + return 0; + + /* + * If uart1_pins are used for serial, AP UART lines have to be muxed + * in PMU block to UART_DEBUG_1 path (GPIO_1). By default (reset value) + * UART_DEBUG_0 path (uart0_pins) is connected to AP UART lines. + */ + offset = EXYNOS850_UART_IO_SHARE_CTRL; + mask = SEL_RXD_AP_UART_MASK | SEL_TXD_GPIO_1_MASK; + value = RXD_GPIO_1 << SEL_RXD_AP_UART_SHIFT | + TXD_AP_UART << SEL_TXD_GPIO_1_SHIFT; + return regmap_update_bits(priv->regmap, offset, mask, value); +} + +static const struct exynos_pmu_data exynos850_pmu_data = { + .pmu_init = exynos850_pmu_init, +}; + +static int exynos_pmu_bind(struct udevice *dev) +{ + dev_or_flags(dev, DM_FLAG_PROBE_AFTER_BIND); + return 0; +} + +static int exynos_pmu_probe(struct udevice *dev) +{ + ofnode node; + struct exynos_pmu *priv; + + priv = dev_get_priv(dev); + priv->dev = dev; + + node = dev_ofnode(dev); + priv->regmap = syscon_node_to_regmap(node); + if (IS_ERR(priv->regmap)) + return PTR_ERR(priv->regmap); + + priv->pmu_data = (struct exynos_pmu_data *)dev_get_driver_data(dev); + if (priv->pmu_data && priv->pmu_data->pmu_init) + return priv->pmu_data->pmu_init(priv); + + return 0; +} + +static const struct udevice_id exynos_pmu_ids[] = { + { + .compatible = "samsung,exynos850-pmu", + .data = (ulong)&exynos850_pmu_data + }, + { /* sentinel */ } +}; + +U_BOOT_DRIVER(exynos_pmu) = { + .name = "exynos-pmu", + .id = UCLASS_NOP, + .of_match = exynos_pmu_ids, + .bind = exynos_pmu_bind, + .probe = exynos_pmu_probe, + .priv_auto = sizeof(struct exynos_pmu), +}; -- 2.39.5