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author | 2023-10-10 14:33:42 +0000 | |
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committer | 2023-10-10 14:33:42 +0000 | |
commit | af1a266670d040d2f4083ff309d732d648afba2a (patch) | |
tree | 2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/u-boot/drivers/serial/serial_owl.c | |
parent | e02cda008591317b1625707ff8e115a4841aa889 (diff) |
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/u-boot/drivers/serial/serial_owl.c')
-rw-r--r-- | roms/u-boot/drivers/serial/serial_owl.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/serial/serial_owl.c b/roms/u-boot/drivers/serial/serial_owl.c new file mode 100644 index 000000000..3b795785f --- /dev/null +++ b/roms/u-boot/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> +#include <linux/bitops.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_of_to_plat(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,owl-uart" }, + { } +}; + +U_BOOT_DRIVER(serial_owl) = { + .name = "serial_owl", + .id = UCLASS_SERIAL, + .of_match = owl_serial_ids, + .of_to_plat = owl_serial_of_to_plat, + .priv_auto = sizeof(struct owl_serial_priv), + .probe = owl_serial_probe, + .ops = &owl_serial_ops, +}; |