2 * Copyright 2013 Freescale Semiconductor, Inc.
4 * SPDX-License-Identifier: GPL-2.0+
11 #include <linux/compiler.h>
12 #include <asm/arch/imx-regs.h>
13 #include <asm/arch/clock.h>
15 #define US1_TDRE (1 << 7)
16 #define US1_RDRF (1 << 5)
17 #define US1_OR (1 << 3)
18 #define UC2_TE (1 << 3)
19 #define UC2_RE (1 << 2)
20 #define CFIFO_TXFLUSH (1 << 7)
21 #define CFIFO_RXFLUSH (1 << 6)
22 #define SFIFO_RXOF (1 << 2)
23 #define SFIFO_RXUF (1 << 0)
25 #define STAT_LBKDIF (1 << 31)
26 #define STAT_RXEDGIF (1 << 30)
27 #define STAT_TDRE (1 << 23)
28 #define STAT_RDRF (1 << 21)
29 #define STAT_IDLE (1 << 20)
30 #define STAT_OR (1 << 19)
31 #define STAT_NF (1 << 18)
32 #define STAT_FE (1 << 17)
33 #define STAT_PF (1 << 16)
34 #define STAT_MA1F (1 << 15)
35 #define STAT_MA2F (1 << 14)
36 #define STAT_FLAGS (STAT_LBKDIF | STAT_RXEDGIF | STAT_IDLE | STAT_OR | \
37 STAT_NF | STAT_FE | STAT_PF | STAT_MA1F | STAT_MA2F)
39 #define CTRL_TE (1 << 19)
40 #define CTRL_RE (1 << 18)
42 #define FIFO_TXFE 0x80
43 #define FIFO_RXFE 0x40
45 #define WATER_TXWATER_OFF 1
46 #define WATER_RXWATER_OFF 16
48 DECLARE_GLOBAL_DATA_PTR;
50 struct lpuart_fsl *base = (struct lpuart_fsl *)LPUART_BASE;
52 #ifndef CONFIG_LPUART_32B_REG
53 static void lpuart_serial_setbrg(void)
55 u32 clk = mxc_get_clock(MXC_UART_CLK);
59 gd->baudrate = CONFIG_BAUDRATE;
61 sbr = (u16)(clk / (16 * gd->baudrate));
63 /* place adjustment later - n/32 BRFA */
64 __raw_writeb(sbr >> 8, &base->ubdh);
65 __raw_writeb(sbr & 0xff, &base->ubdl);
68 static int lpuart_serial_getc(void)
70 while (!(__raw_readb(&base->us1) & (US1_RDRF | US1_OR)))
75 return __raw_readb(&base->ud);
78 static void lpuart_serial_putc(const char c)
81 lpuart_serial_putc('\r');
83 while (!(__raw_readb(&base->us1) & US1_TDRE))
86 __raw_writeb(c, &base->ud);
89 /* Test whether a character is in the RX buffer */
90 static int lpuart_serial_tstc(void)
92 if (__raw_readb(&base->urcfifo) == 0)
99 * Initialise the serial port with the given baudrate. The settings
100 * are always 8 data bits, no parity, 1 stop bit, no start bits.
102 static int lpuart_serial_init(void)
106 ctrl = __raw_readb(&base->uc2);
109 __raw_writeb(ctrl, &base->uc2);
111 __raw_writeb(0, &base->umodem);
112 __raw_writeb(0, &base->uc1);
114 /* Disable FIFO and flush buffer */
115 __raw_writeb(0x0, &base->upfifo);
116 __raw_writeb(0x0, &base->utwfifo);
117 __raw_writeb(0x1, &base->urwfifo);
118 __raw_writeb(CFIFO_TXFLUSH | CFIFO_RXFLUSH, &base->ucfifo);
120 /* provide data bits, parity, stop bit, etc */
121 lpuart_serial_setbrg();
123 __raw_writeb(UC2_RE | UC2_TE, &base->uc2);
128 static struct serial_device lpuart_serial_drv = {
129 .name = "lpuart_serial",
130 .start = lpuart_serial_init,
132 .setbrg = lpuart_serial_setbrg,
133 .putc = lpuart_serial_putc,
134 .puts = default_serial_puts,
135 .getc = lpuart_serial_getc,
136 .tstc = lpuart_serial_tstc,
139 static void lpuart32_serial_setbrg(void)
141 u32 clk = CONFIG_SYS_CLK_FREQ;
145 gd->baudrate = CONFIG_BAUDRATE;
147 sbr = (clk / (16 * gd->baudrate));
149 /* place adjustment later - n/32 BRFA */
150 out_be32(&base->baud, sbr);
153 static int lpuart32_serial_getc(void)
157 while (((stat = in_be32(&base->stat)) & STAT_RDRF) == 0) {
158 out_be32(&base->stat, STAT_FLAGS);
162 return in_be32(&base->data) & 0x3ff;
165 static void lpuart32_serial_putc(const char c)
168 lpuart32_serial_putc('\r');
170 while (!(in_be32(&base->stat) & STAT_TDRE))
173 out_be32(&base->data, c);
176 /* Test whether a character is in the RX buffer */
177 static int lpuart32_serial_tstc(void)
179 if ((in_be32(&base->water) >> 24) == 0)
186 * Initialise the serial port with the given baudrate. The settings
187 * are always 8 data bits, no parity, 1 stop bit, no start bits.
189 static int lpuart32_serial_init(void)
193 ctrl = in_be32(&base->ctrl);
196 out_be32(&base->ctrl, ctrl);
198 out_be32(&base->modir, 0);
199 out_be32(&base->fifo, ~(FIFO_TXFE | FIFO_RXFE));
201 out_be32(&base->match, 0);
203 /* provide data bits, parity, stop bit, etc */
204 lpuart32_serial_setbrg();
206 out_be32(&base->ctrl, CTRL_RE | CTRL_TE);
211 static struct serial_device lpuart32_serial_drv = {
212 .name = "lpuart32_serial",
213 .start = lpuart32_serial_init,
215 .setbrg = lpuart32_serial_setbrg,
216 .putc = lpuart32_serial_putc,
217 .puts = default_serial_puts,
218 .getc = lpuart32_serial_getc,
219 .tstc = lpuart32_serial_tstc,
223 void lpuart_serial_initialize(void)
225 #ifdef CONFIG_LPUART_32B_REG
226 serial_register(&lpuart32_serial_drv);
228 serial_register(&lpuart_serial_drv);
232 __weak struct serial_device *default_serial_console(void)
234 #ifdef CONFIG_LPUART_32B_REG
235 return &lpuart32_serial_drv;
237 return &lpuart_serial_drv;