This commit adds Actions Semi OWL family UART support. This driver relies on baudrate configured by primary bootloaders.
Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org --- drivers/serial/Kconfig | 8 +++ drivers/serial/Makefile | 1 + drivers/serial/serial_owl.c | 136 ++++++++++++++++++++++++++++++++++++ 3 files changed, 145 insertions(+) create mode 100644 drivers/serial/serial_owl.c
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index 2940bd05dc..766e5ced03 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -625,6 +625,14 @@ config MSM_SERIAL for example APQ8016 and MSM8916. Single baudrate is supported in current implementation (115200).
+config OWL_SERIAL + bool "Actions Semi OWL UART" + depends on DM_SERIAL && ARCH_OWL + help + If you have a Actions Semi OWL based board and want to use the on-chip + serial port, say Y to this option. If unsure, say N. + Single baudrate is supported in current implementation (115200). + config PXA_SERIAL bool "PXA serial port support" help diff --git a/drivers/serial/Makefile b/drivers/serial/Makefile index e66899489e..9fa81d855d 100644 --- a/drivers/serial/Makefile +++ b/drivers/serial/Makefile @@ -64,6 +64,7 @@ obj-$(CONFIG_MSM_SERIAL) += serial_msm.o obj-$(CONFIG_MVEBU_A3700_UART) += serial_mvebu_a3700.o obj-$(CONFIG_MPC8XX_CONS) += serial_mpc8xx.o obj-$(CONFIG_NULLDEV_SERIAL) += serial_nulldev.o +obj-$(CONFIG_OWL_SERIAL) += serial_owl.o
ifndef CONFIG_SPL_BUILD obj-$(CONFIG_USB_TTY) += usbtty.o diff --git a/drivers/serial/serial_owl.c b/drivers/serial/serial_owl.c new file mode 100644 index 0000000000..6fd97e2502 --- /dev/null +++ b/drivers/serial/serial_owl.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Actions Semi OWL SoCs UART driver + * + * Copyright (C) 2015 Actions Semi Co., Ltd. + * Copyright (C) 2018 Manivannan Sadhasivam manivannan.sadhasivam@linaro.org + */ + +#include <common.h> +#include <clk.h> +#include <dm.h> +#include <errno.h> +#include <fdtdec.h> +#include <serial.h> +#include <asm/io.h> +#include <asm/types.h> + +/* UART Registers */ +#define OWL_UART_CTL (0x0000) +#define OWL_UART_RXDAT (0x0004) +#define OWL_UART_TXDAT (0x0008) +#define OWL_UART_STAT (0x000C) + +/* UART_CTL Register Definitions */ +#define OWL_UART_CTL_PRS_NONE GENMASK(6, 4) +#define OWL_UART_CTL_STPS BIT(2) +#define OWL_UART_CTL_DWLS 3 + +/* UART_STAT Register Definitions */ +#define OWL_UART_STAT_TFES BIT(10) /* TX FIFO Empty Status */ +#define OWL_UART_STAT_RFFS BIT(9) /* RX FIFO full Status */ +#define OWL_UART_STAT_TFFU BIT(6) /* TX FIFO full Status */ +#define OWL_UART_STAT_RFEM BIT(5) /* RX FIFO Empty Status */ + +struct owl_serial_priv { + phys_addr_t base; +}; + +int owl_serial_setbrg(struct udevice *dev, int baudrate) +{ + /* Driver supports only fixed baudrate */ + return 0; +} + +static int owl_serial_getc(struct udevice *dev) +{ + struct owl_serial_priv *priv = dev_get_priv(dev); + + if (readl(priv->base + OWL_UART_STAT) & OWL_UART_STAT_RFEM) + return -EAGAIN; + + return (int)(readl(priv->base + OWL_UART_RXDAT)); +} + +static int owl_serial_putc(struct udevice *dev, const char ch) +{ + struct owl_serial_priv *priv = dev_get_priv(dev); + + if (readl(priv->base + OWL_UART_STAT) & OWL_UART_STAT_TFFU) + return -EAGAIN; + + writel(ch, priv->base + OWL_UART_TXDAT); + + return 0; +} + +static int owl_serial_pending(struct udevice *dev, bool input) +{ + struct owl_serial_priv *priv = dev_get_priv(dev); + unsigned int stat = readl(priv->base + OWL_UART_STAT); + + if (input) + return !(stat & OWL_UART_STAT_RFEM); + else + return !(stat & OWL_UART_STAT_TFES); +} + +static int owl_serial_probe(struct udevice *dev) +{ + struct owl_serial_priv *priv = dev_get_priv(dev); + struct clk clk; + u32 uart_ctl; + int ret; + + /* Set data, parity and stop bits */ + uart_ctl = readl(priv->base + OWL_UART_CTL); + uart_ctl &= ~(OWL_UART_CTL_PRS_NONE); + uart_ctl &= ~(OWL_UART_CTL_STPS); + uart_ctl |= OWL_UART_CTL_DWLS; + writel(uart_ctl, priv->base + OWL_UART_CTL); + + /* Enable UART clock */ + ret = clk_get_by_index(dev, 0, &clk); + if (ret < 0) + return ret; + + ret = clk_enable(&clk); + if (ret < 0) + return ret; + + return 0; +} + +static int owl_serial_ofdata_to_platdata(struct udevice *dev) +{ + struct owl_serial_priv *priv = dev_get_priv(dev); + + priv->base = dev_read_addr(dev); + if (priv->base == FDT_ADDR_T_NONE) + return -EINVAL; + + return 0; +} + +static const struct dm_serial_ops owl_serial_ops = { + .putc = owl_serial_putc, + .pending = owl_serial_pending, + .getc = owl_serial_getc, + .setbrg = owl_serial_setbrg, +}; + +static const struct udevice_id owl_serial_ids[] = { + { .compatible = "actions,s900-serial" }, + { } +}; + +U_BOOT_DRIVER(serial_owl) = { + .name = "serial_owl", + .id = UCLASS_SERIAL, + .of_match = owl_serial_ids, + .ofdata_to_platdata = owl_serial_ofdata_to_platdata, + .priv_auto_alloc_size = sizeof(struct owl_serial_priv), + .probe = owl_serial_probe, + .ops = &owl_serial_ops, + .flags = DM_FLAG_PRE_RELOC, +};