diff options
Diffstat (limited to 'roms/u-boot/drivers/serial/serial_s5p.c')
| -rw-r--r-- | roms/u-boot/drivers/serial/serial_s5p.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/serial/serial_s5p.c b/roms/u-boot/drivers/serial/serial_s5p.c new file mode 100644 index 000000000..6d09952a5 --- /dev/null +++ b/roms/u-boot/drivers/serial/serial_s5p.c @@ -0,0 +1,241 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * (C) Copyright 2009 SAMSUNG Electronics + * Minkyu Kang <mk7.kang@samsung.com> + * Heungjun Kim <riverful.kim@samsung.com> + * + * based on drivers/serial/s3c64xx.c + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <fdtdec.h> +#include <asm/global_data.h> +#include <linux/compiler.h> +#include <asm/io.h> +#include <asm/arch/clk.h> +#include <asm/arch/uart.h> +#include <serial.h> +#include <clk.h> + +DECLARE_GLOBAL_DATA_PTR; + +#define RX_FIFO_COUNT_SHIFT 0 +#define RX_FIFO_COUNT_MASK (0xff << RX_FIFO_COUNT_SHIFT) +#define RX_FIFO_FULL (1 << 8) +#define TX_FIFO_COUNT_SHIFT 16 +#define TX_FIFO_COUNT_MASK (0xff << TX_FIFO_COUNT_SHIFT) +#define TX_FIFO_FULL (1 << 24) + +/* Information about a serial port */ +struct s5p_serial_plat { + struct s5p_uart *reg; /* address of registers in physical memory */ + u8 port_id; /* uart port number */ +}; + +/* + * The coefficient, used to calculate the baudrate on S5P UARTs is + * calculated as + * C = UBRDIV * 16 + number_of_set_bits_in_UDIVSLOT + * however, section 31.6.11 of the datasheet doesn't recomment using 1 for 1, + * 3 for 2, ... (2^n - 1) for n, instead, they suggest using these constants: + */ +static const int udivslot[] = { + 0, + 0x0080, + 0x0808, + 0x0888, + 0x2222, + 0x4924, + 0x4a52, + 0x54aa, + 0x5555, + 0xd555, + 0xd5d5, + 0xddd5, + 0xdddd, + 0xdfdd, + 0xdfdf, + 0xffdf, +}; + +static void __maybe_unused s5p_serial_init(struct s5p_uart *uart) +{ + /* enable FIFOs, auto clear Rx FIFO */ + writel(0x3, &uart->ufcon); + writel(0, &uart->umcon); + /* 8N1 */ + writel(0x3, &uart->ulcon); + /* No interrupts, no DMA, pure polling */ + writel(0x245, &uart->ucon); +} + +static void __maybe_unused s5p_serial_baud(struct s5p_uart *uart, uint uclk, + int baudrate) +{ + u32 val; + + val = uclk / baudrate; + + writel(val / 16 - 1, &uart->ubrdiv); + + if (s5p_uart_divslot()) + writew(udivslot[val % 16], &uart->rest.slot); + else + writeb(val % 16, &uart->rest.value); +} + +#ifndef CONFIG_SPL_BUILD +int s5p_serial_setbrg(struct udevice *dev, int baudrate) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + struct s5p_uart *const uart = plat->reg; + u32 uclk; + +#ifdef CONFIG_CLK_EXYNOS + struct clk clk; + u32 ret; + + ret = clk_get_by_index(dev, 1, &clk); + if (ret < 0) + return ret; + uclk = clk_get_rate(&clk); +#else + uclk = get_uart_clk(plat->port_id); +#endif + + s5p_serial_baud(uart, uclk, baudrate); + + return 0; +} + +static int s5p_serial_probe(struct udevice *dev) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + struct s5p_uart *const uart = plat->reg; + + s5p_serial_init(uart); + + return 0; +} + +static int serial_err_check(const struct s5p_uart *const uart, int op) +{ + unsigned int mask; + + /* + * UERSTAT + * Break Detect [3] + * Frame Err [2] : receive operation + * Parity Err [1] : receive operation + * Overrun Err [0] : receive operation + */ + if (op) + mask = 0x8; + else + mask = 0xf; + + return readl(&uart->uerstat) & mask; +} + +static int s5p_serial_getc(struct udevice *dev) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + struct s5p_uart *const uart = plat->reg; + + if (!(readl(&uart->ufstat) & RX_FIFO_COUNT_MASK)) + return -EAGAIN; + + serial_err_check(uart, 0); + return (int)(readb(&uart->urxh) & 0xff); +} + +static int s5p_serial_putc(struct udevice *dev, const char ch) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + struct s5p_uart *const uart = plat->reg; + + if (readl(&uart->ufstat) & TX_FIFO_FULL) + return -EAGAIN; + + writeb(ch, &uart->utxh); + serial_err_check(uart, 1); + + return 0; +} + +static int s5p_serial_pending(struct udevice *dev, bool input) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + struct s5p_uart *const uart = plat->reg; + uint32_t ufstat = readl(&uart->ufstat); + + if (input) + return (ufstat & RX_FIFO_COUNT_MASK) >> RX_FIFO_COUNT_SHIFT; + else + return (ufstat & TX_FIFO_COUNT_MASK) >> TX_FIFO_COUNT_SHIFT; +} + +static int s5p_serial_of_to_plat(struct udevice *dev) +{ + struct s5p_serial_plat *plat = dev_get_plat(dev); + fdt_addr_t addr; + + addr = dev_read_addr(dev); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + + plat->reg = (struct s5p_uart *)addr; + plat->port_id = fdtdec_get_int(gd->fdt_blob, dev_of_offset(dev), + "id", dev_seq(dev)); + return 0; +} + +static const struct dm_serial_ops s5p_serial_ops = { + .putc = s5p_serial_putc, + .pending = s5p_serial_pending, + .getc = s5p_serial_getc, + .setbrg = s5p_serial_setbrg, +}; + +static const struct udevice_id s5p_serial_ids[] = { + { .compatible = "samsung,exynos4210-uart" }, + { } +}; + +U_BOOT_DRIVER(serial_s5p) = { + .name = "serial_s5p", + .id = UCLASS_SERIAL, + .of_match = s5p_serial_ids, + .of_to_plat = s5p_serial_of_to_plat, + .plat_auto = sizeof(struct s5p_serial_plat), + .probe = s5p_serial_probe, + .ops = &s5p_serial_ops, +}; +#endif + +#ifdef CONFIG_DEBUG_UART_S5P + +#include <debug_uart.h> + +static inline void _debug_uart_init(void) +{ + struct s5p_uart *uart = (struct s5p_uart *)CONFIG_DEBUG_UART_BASE; + + s5p_serial_init(uart); + s5p_serial_baud(uart, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE); +} + +static inline void _debug_uart_putc(int ch) +{ + struct s5p_uart *uart = (struct s5p_uart *)CONFIG_DEBUG_UART_BASE; + + while (readl(&uart->ufstat) & TX_FIFO_FULL); + + writeb(ch, &uart->utxh); +} + +DEBUG_UART_FUNCS + +#endif |