diff options
Diffstat (limited to 'roms/u-boot/drivers/serial/serial_mtk.c')
| -rw-r--r-- | roms/u-boot/drivers/serial/serial_mtk.c | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/serial/serial_mtk.c b/roms/u-boot/drivers/serial/serial_mtk.c new file mode 100644 index 000000000..4145d9fdb --- /dev/null +++ b/roms/u-boot/drivers/serial/serial_mtk.c @@ -0,0 +1,452 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * MediaTek High-speed UART driver + * + * Copyright (C) 2018 MediaTek Inc. + * Author: Weijie Gao <weijie.gao@mediatek.com> + */ + +#include <clk.h> +#include <common.h> +#include <div64.h> +#include <dm.h> +#include <errno.h> +#include <log.h> +#include <serial.h> +#include <watchdog.h> +#include <asm/global_data.h> +#include <asm/io.h> +#include <asm/types.h> +#include <linux/err.h> + +struct mtk_serial_regs { + u32 rbr; + u32 ier; + u32 fcr; + u32 lcr; + u32 mcr; + u32 lsr; + u32 msr; + u32 spr; + u32 mdr1; + u32 highspeed; + u32 sample_count; + u32 sample_point; + u32 fracdiv_l; + u32 fracdiv_m; + u32 escape_en; + u32 guard; + u32 rx_sel; +}; + +#define thr rbr +#define iir fcr +#define dll rbr +#define dlm ier + +#define UART_LCR_WLS_8 0x03 /* 8 bit character length */ +#define UART_LCR_DLAB 0x80 /* Divisor latch access bit */ + +#define UART_LSR_DR 0x01 /* Data ready */ +#define UART_LSR_THRE 0x20 /* Xmit holding register empty */ +#define UART_LSR_TEMT 0x40 /* Xmitter empty */ + +#define UART_MCR_DTR 0x01 /* DTR */ +#define UART_MCR_RTS 0x02 /* RTS */ + +#define UART_FCR_FIFO_EN 0x01 /* Fifo enable */ +#define UART_FCR_RXSR 0x02 /* Receiver soft reset */ +#define UART_FCR_TXSR 0x04 /* Transmitter soft reset */ + +#define UART_MCRVAL (UART_MCR_DTR | \ + UART_MCR_RTS) + +/* Clear & enable FIFOs */ +#define UART_FCRVAL (UART_FCR_FIFO_EN | \ + UART_FCR_RXSR | \ + UART_FCR_TXSR) + +/* the data is correct if the real baud is within 3%. */ +#define BAUD_ALLOW_MAX(baud) ((baud) + (baud) * 3 / 100) +#define BAUD_ALLOW_MIX(baud) ((baud) - (baud) * 3 / 100) + +struct mtk_serial_priv { + struct mtk_serial_regs __iomem *regs; + u32 clock; + bool force_highspeed; +}; + +static void _mtk_serial_setbrg(struct mtk_serial_priv *priv, int baud) +{ + u32 quot, realbaud, samplecount = 1; + + /* Special case for low baud clock */ + if (baud <= 115200 && priv->clock <= 12000000) { + writel(3, &priv->regs->highspeed); + + quot = DIV_ROUND_CLOSEST(priv->clock, 256 * baud); + if (quot == 0) + quot = 1; + + samplecount = DIV_ROUND_CLOSEST(priv->clock, quot * baud); + + realbaud = priv->clock / samplecount / quot; + if (realbaud > BAUD_ALLOW_MAX(baud) || + realbaud < BAUD_ALLOW_MIX(baud)) { + pr_info("baud %d can't be handled\n", baud); + } + + goto set_baud; + } + + if (priv->force_highspeed) + goto use_hs3; + + if (baud <= 115200) { + writel(0, &priv->regs->highspeed); + quot = DIV_ROUND_CLOSEST(priv->clock, 16 * baud); + } else if (baud <= 576000) { + writel(2, &priv->regs->highspeed); + + /* Set to next lower baudrate supported */ + if ((baud == 500000) || (baud == 576000)) + baud = 460800; + + quot = DIV_ROUND_UP(priv->clock, 4 * baud); + } else { +use_hs3: + writel(3, &priv->regs->highspeed); + + quot = DIV_ROUND_UP(priv->clock, 256 * baud); + samplecount = DIV_ROUND_CLOSEST(priv->clock, quot * baud); + } + +set_baud: + /* set divisor */ + writel(UART_LCR_WLS_8 | UART_LCR_DLAB, &priv->regs->lcr); + writel(quot & 0xff, &priv->regs->dll); + writel((quot >> 8) & 0xff, &priv->regs->dlm); + writel(UART_LCR_WLS_8, &priv->regs->lcr); + + /* set highspeed mode sample count & point */ + writel(samplecount - 1, &priv->regs->sample_count); + writel((samplecount - 2) >> 1, &priv->regs->sample_point); +} + +static int _mtk_serial_putc(struct mtk_serial_priv *priv, const char ch) +{ + if (!(readl(&priv->regs->lsr) & UART_LSR_THRE)) + return -EAGAIN; + + writel(ch, &priv->regs->thr); + + if (ch == '\n') + WATCHDOG_RESET(); + + return 0; +} + +static int _mtk_serial_getc(struct mtk_serial_priv *priv) +{ + if (!(readl(&priv->regs->lsr) & UART_LSR_DR)) + return -EAGAIN; + + return readl(&priv->regs->rbr); +} + +static int _mtk_serial_pending(struct mtk_serial_priv *priv, bool input) +{ + if (input) + return (readl(&priv->regs->lsr) & UART_LSR_DR) ? 1 : 0; + else + return (readl(&priv->regs->lsr) & UART_LSR_THRE) ? 0 : 1; +} + +#if defined(CONFIG_DM_SERIAL) && \ + (!defined(CONFIG_SPL_BUILD) || defined(CONFIG_SPL_DM)) +static int mtk_serial_setbrg(struct udevice *dev, int baudrate) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + + _mtk_serial_setbrg(priv, baudrate); + + return 0; +} + +static int mtk_serial_putc(struct udevice *dev, const char ch) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + + return _mtk_serial_putc(priv, ch); +} + +static int mtk_serial_getc(struct udevice *dev) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + + return _mtk_serial_getc(priv); +} + +static int mtk_serial_pending(struct udevice *dev, bool input) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + + return _mtk_serial_pending(priv, input); +} + +static int mtk_serial_probe(struct udevice *dev) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + + /* Disable interrupt */ + writel(0, &priv->regs->ier); + + writel(UART_MCRVAL, &priv->regs->mcr); + writel(UART_FCRVAL, &priv->regs->fcr); + + return 0; +} + +static int mtk_serial_of_to_plat(struct udevice *dev) +{ + struct mtk_serial_priv *priv = dev_get_priv(dev); + fdt_addr_t addr; + struct clk clk; + int err; + + addr = dev_read_addr(dev); + if (addr == FDT_ADDR_T_NONE) + return -EINVAL; + + priv->regs = map_physmem(addr, 0, MAP_NOCACHE); + + err = clk_get_by_index(dev, 0, &clk); + if (!err) { + err = clk_get_rate(&clk); + if (!IS_ERR_VALUE(err)) + priv->clock = err; + } else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) { + debug("mtk_serial: failed to get clock\n"); + return err; + } + + if (!priv->clock) + priv->clock = dev_read_u32_default(dev, "clock-frequency", 0); + + if (!priv->clock) { + debug("mtk_serial: clock not defined\n"); + return -EINVAL; + } + + priv->force_highspeed = dev_read_bool(dev, "mediatek,force-highspeed"); + + return 0; +} + +static const struct dm_serial_ops mtk_serial_ops = { + .putc = mtk_serial_putc, + .pending = mtk_serial_pending, + .getc = mtk_serial_getc, + .setbrg = mtk_serial_setbrg, +}; + +static const struct udevice_id mtk_serial_ids[] = { + { .compatible = "mediatek,hsuart" }, + { .compatible = "mediatek,mt6577-uart" }, + { } +}; + +U_BOOT_DRIVER(serial_mtk) = { + .name = "serial_mtk", + .id = UCLASS_SERIAL, + .of_match = mtk_serial_ids, + .of_to_plat = mtk_serial_of_to_plat, + .priv_auto = sizeof(struct mtk_serial_priv), + .probe = mtk_serial_probe, + .ops = &mtk_serial_ops, + .flags = DM_FLAG_PRE_RELOC, +}; +#else + +DECLARE_GLOBAL_DATA_PTR; + +#define DECLARE_HSUART_PRIV(port) \ + static struct mtk_serial_priv mtk_hsuart##port = { \ + .regs = (struct mtk_serial_regs *)CONFIG_SYS_NS16550_COM##port, \ + .clock = CONFIG_SYS_NS16550_CLK \ +}; + +#define DECLARE_HSUART_FUNCTIONS(port) \ + static int mtk_serial##port##_init(void) \ + { \ + writel(0, &mtk_hsuart##port.regs->ier); \ + writel(UART_MCRVAL, &mtk_hsuart##port.regs->mcr); \ + writel(UART_FCRVAL, &mtk_hsuart##port.regs->fcr); \ + _mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate); \ + return 0 ; \ + } \ + static void mtk_serial##port##_setbrg(void) \ + { \ + _mtk_serial_setbrg(&mtk_hsuart##port, gd->baudrate); \ + } \ + static int mtk_serial##port##_getc(void) \ + { \ + int err; \ + do { \ + err = _mtk_serial_getc(&mtk_hsuart##port); \ + if (err == -EAGAIN) \ + WATCHDOG_RESET(); \ + } while (err == -EAGAIN); \ + return err >= 0 ? err : 0; \ + } \ + static int mtk_serial##port##_tstc(void) \ + { \ + return _mtk_serial_pending(&mtk_hsuart##port, true); \ + } \ + static void mtk_serial##port##_putc(const char c) \ + { \ + int err; \ + if (c == '\n') \ + mtk_serial##port##_putc('\r'); \ + do { \ + err = _mtk_serial_putc(&mtk_hsuart##port, c); \ + } while (err == -EAGAIN); \ + } \ + static void mtk_serial##port##_puts(const char *s) \ + { \ + while (*s) { \ + mtk_serial##port##_putc(*s++); \ + } \ + } + +/* Serial device descriptor */ +#define INIT_HSUART_STRUCTURE(port, __name) { \ + .name = __name, \ + .start = mtk_serial##port##_init, \ + .stop = NULL, \ + .setbrg = mtk_serial##port##_setbrg, \ + .getc = mtk_serial##port##_getc, \ + .tstc = mtk_serial##port##_tstc, \ + .putc = mtk_serial##port##_putc, \ + .puts = mtk_serial##port##_puts, \ +} + +#define DECLARE_HSUART(port, __name) \ + DECLARE_HSUART_PRIV(port); \ + DECLARE_HSUART_FUNCTIONS(port); \ + struct serial_device mtk_hsuart##port##_device = \ + INIT_HSUART_STRUCTURE(port, __name); + +#if !defined(CONFIG_CONS_INDEX) +#elif (CONFIG_CONS_INDEX < 1) || (CONFIG_CONS_INDEX > 6) +#error "Invalid console index value." +#endif + +#if CONFIG_CONS_INDEX == 1 && !defined(CONFIG_SYS_NS16550_COM1) +#error "Console port 1 defined but not configured." +#elif CONFIG_CONS_INDEX == 2 && !defined(CONFIG_SYS_NS16550_COM2) +#error "Console port 2 defined but not configured." +#elif CONFIG_CONS_INDEX == 3 && !defined(CONFIG_SYS_NS16550_COM3) +#error "Console port 3 defined but not configured." +#elif CONFIG_CONS_INDEX == 4 && !defined(CONFIG_SYS_NS16550_COM4) +#error "Console port 4 defined but not configured." +#elif CONFIG_CONS_INDEX == 5 && !defined(CONFIG_SYS_NS16550_COM5) +#error "Console port 5 defined but not configured." +#elif CONFIG_CONS_INDEX == 6 && !defined(CONFIG_SYS_NS16550_COM6) +#error "Console port 6 defined but not configured." +#endif + +#if defined(CONFIG_SYS_NS16550_COM1) +DECLARE_HSUART(1, "mtk-hsuart0"); +#endif +#if defined(CONFIG_SYS_NS16550_COM2) +DECLARE_HSUART(2, "mtk-hsuart1"); +#endif +#if defined(CONFIG_SYS_NS16550_COM3) +DECLARE_HSUART(3, "mtk-hsuart2"); +#endif +#if defined(CONFIG_SYS_NS16550_COM4) +DECLARE_HSUART(4, "mtk-hsuart3"); +#endif +#if defined(CONFIG_SYS_NS16550_COM5) +DECLARE_HSUART(5, "mtk-hsuart4"); +#endif +#if defined(CONFIG_SYS_NS16550_COM6) +DECLARE_HSUART(6, "mtk-hsuart5"); +#endif + +__weak struct serial_device *default_serial_console(void) +{ +#if CONFIG_CONS_INDEX == 1 + return &mtk_hsuart1_device; +#elif CONFIG_CONS_INDEX == 2 + return &mtk_hsuart2_device; +#elif CONFIG_CONS_INDEX == 3 + return &mtk_hsuart3_device; +#elif CONFIG_CONS_INDEX == 4 + return &mtk_hsuart4_device; +#elif CONFIG_CONS_INDEX == 5 + return &mtk_hsuart5_device; +#elif CONFIG_CONS_INDEX == 6 + return &mtk_hsuart6_device; +#else +#error "Bad CONFIG_CONS_INDEX." +#endif +} + +void mtk_serial_initialize(void) +{ +#if defined(CONFIG_SYS_NS16550_COM1) + serial_register(&mtk_hsuart1_device); +#endif +#if defined(CONFIG_SYS_NS16550_COM2) + serial_register(&mtk_hsuart2_device); +#endif +#if defined(CONFIG_SYS_NS16550_COM3) + serial_register(&mtk_hsuart3_device); +#endif +#if defined(CONFIG_SYS_NS16550_COM4) + serial_register(&mtk_hsuart4_device); +#endif +#if defined(CONFIG_SYS_NS16550_COM5) + serial_register(&mtk_hsuart5_device); +#endif +#if defined(CONFIG_SYS_NS16550_COM6) + serial_register(&mtk_hsuart6_device); +#endif +} + +#endif + +#ifdef CONFIG_DEBUG_UART_MTK + +#include <debug_uart.h> + +static inline void _debug_uart_init(void) +{ + struct mtk_serial_priv priv; + + priv.regs = (void *) CONFIG_DEBUG_UART_BASE; + priv.clock = CONFIG_DEBUG_UART_CLOCK; + + writel(0, &priv.regs->ier); + writel(UART_MCRVAL, &priv.regs->mcr); + writel(UART_FCRVAL, &priv.regs->fcr); + + _mtk_serial_setbrg(&priv, CONFIG_BAUDRATE); +} + +static inline void _debug_uart_putc(int ch) +{ + struct mtk_serial_regs __iomem *regs = + (void *) CONFIG_DEBUG_UART_BASE; + + while (!(readl(®s->lsr) & UART_LSR_THRE)) + ; + + writel(ch, ®s->thr); +} + +DEBUG_UART_FUNCS + +#endif |