2 * Copyright (c) 2012 Semihalf.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
34 #include <machine/bus.h>
36 #include <dev/uart/uart.h>
37 #include <dev/uart/uart_cpu.h>
38 #include <dev/uart/uart_cpu_fdt.h>
39 #include <dev/uart/uart_bus.h>
44 /* PL011 UART registers and masks*/
45 #define UART_DR 0x00 /* Data register */
46 #define DR_FE (1 << 8) /* Framing error */
47 #define DR_PE (1 << 9) /* Parity error */
48 #define DR_BE (1 << 10) /* Break error */
49 #define DR_OE (1 << 11) /* Overrun error */
51 #define UART_FR 0x06 /* Flag register */
52 #define FR_TXFF (1 << 5) /* Transmit FIFO/reg full */
53 #define FR_RXFF (1 << 6) /* Receive FIFO/reg full */
54 #define FR_TXFE (1 << 7) /* Transmit FIFO/reg empty */
56 #define UART_IBRD 0x09 /* Integer baud rate register */
57 #define IBRD_BDIVINT 0xffff /* Significant part of int. divisor value */
59 #define UART_FBRD 0x0a /* Fractional baud rate register */
60 #define FBRD_BDIVFRAC 0x3f /* Significant part of frac. divisor value */
62 #define UART_LCR_H 0x0b /* Line control register */
63 #define LCR_H_WLEN8 (0x3 << 5)
64 #define LCR_H_WLEN7 (0x2 << 5)
65 #define LCR_H_WLEN6 (0x1 << 5)
66 #define LCR_H_FEN (1 << 4) /* FIFO mode enable */
67 #define LCR_H_STP2 (1 << 3) /* 2 stop frames at the end */
68 #define LCR_H_EPS (1 << 2) /* Even parity select */
69 #define LCR_H_PEN (1 << 1) /* Parity enable */
71 #define UART_CR 0x0c /* Control register */
72 #define CR_RXE (1 << 9) /* Receive enable */
73 #define CR_TXE (1 << 8) /* Transmit enable */
74 #define CR_UARTEN (1 << 0) /* UART enable */
76 #define UART_IMSC 0x0e /* Interrupt mask set/clear register */
77 #define IMSC_MASK_ALL 0x7ff /* Mask all interrupts */
79 #define UART_RIS 0x0f /* Raw interrupt status register */
80 #define UART_RXREADY (1 << 4) /* RX buffer full */
81 #define UART_TXEMPTY (1 << 5) /* TX buffer empty */
82 #define RIS_RTIM (1 << 6) /* Receive timeout */
83 #define RIS_FE (1 << 7) /* Framing error interrupt status */
84 #define RIS_PE (1 << 8) /* Parity error interrupt status */
85 #define RIS_BE (1 << 9) /* Break error interrupt status */
86 #define RIS_OE (1 << 10) /* Overrun interrupt status */
88 #define UART_MIS 0x10 /* Masked interrupt status register */
89 #define UART_ICR 0x11 /* Interrupt clear register */
92 * FIXME: actual register size is SoC-dependent, we need to handle it
94 #define __uart_getreg(bas, reg) \
95 bus_space_read_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg))
96 #define __uart_setreg(bas, reg, value) \
97 bus_space_write_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value)
100 * Low-level UART interface.
102 static int uart_pl011_probe(struct uart_bas *bas);
103 static void uart_pl011_init(struct uart_bas *bas, int, int, int, int);
104 static void uart_pl011_term(struct uart_bas *bas);
105 static void uart_pl011_putc(struct uart_bas *bas, int);
106 static int uart_pl011_rxready(struct uart_bas *bas);
107 static int uart_pl011_getc(struct uart_bas *bas, struct mtx *);
109 static struct uart_ops uart_pl011_ops = {
110 .probe = uart_pl011_probe,
111 .init = uart_pl011_init,
112 .term = uart_pl011_term,
113 .putc = uart_pl011_putc,
114 .rxready = uart_pl011_rxready,
115 .getc = uart_pl011_getc,
119 uart_pl011_probe(struct uart_bas *bas)
126 uart_pl011_param(struct uart_bas *bas, int baudrate, int databits, int stopbits,
133 * Zero all settings to make sure
134 * UART is disabled and not configured
137 __uart_setreg(bas, UART_CR, ctrl);
139 /* As we know UART is disabled we may setup the line */
163 /* Configure the rest */
165 ctrl |= (CR_RXE | CR_TXE | CR_UARTEN);
167 if (bas->rclk != 0 && baudrate != 0) {
168 baud = bas->rclk * 4 / baudrate;
169 __uart_setreg(bas, UART_IBRD, ((uint32_t)(baud >> 6)) & IBRD_BDIVINT);
170 __uart_setreg(bas, UART_FBRD, (uint32_t)(baud & 0x3F) & FBRD_BDIVFRAC);
173 /* Add config. to line before reenabling UART */
174 __uart_setreg(bas, UART_LCR_H, (__uart_getreg(bas, UART_LCR_H) &
177 __uart_setreg(bas, UART_CR, ctrl);
181 uart_pl011_init(struct uart_bas *bas, int baudrate, int databits, int stopbits,
184 /* Mask all interrupts */
185 __uart_setreg(bas, UART_IMSC, __uart_getreg(bas, UART_IMSC) &
188 uart_pl011_param(bas, baudrate, databits, stopbits, parity);
192 uart_pl011_term(struct uart_bas *bas)
197 uart_pl011_putc(struct uart_bas *bas, int c)
200 /* Wait when TX FIFO full. Push character otherwise. */
201 while (__uart_getreg(bas, UART_FR) & FR_TXFF)
203 __uart_setreg(bas, UART_DR, c & 0xff);
207 uart_pl011_rxready(struct uart_bas *bas)
210 return (__uart_getreg(bas, UART_FR) & FR_RXFF);
214 uart_pl011_getc(struct uart_bas *bas, struct mtx *hwmtx)
218 while (!uart_pl011_rxready(bas))
220 c = __uart_getreg(bas, UART_DR) & 0xff;
226 * High-level UART interface.
228 struct uart_pl011_softc {
229 struct uart_softc base;
238 static int uart_pl011_bus_attach(struct uart_softc *);
239 static int uart_pl011_bus_detach(struct uart_softc *);
240 static int uart_pl011_bus_flush(struct uart_softc *, int);
241 static int uart_pl011_bus_getsig(struct uart_softc *);
242 static int uart_pl011_bus_ioctl(struct uart_softc *, int, intptr_t);
243 static int uart_pl011_bus_ipend(struct uart_softc *);
244 static int uart_pl011_bus_param(struct uart_softc *, int, int, int, int);
245 static int uart_pl011_bus_probe(struct uart_softc *);
246 static int uart_pl011_bus_receive(struct uart_softc *);
247 static int uart_pl011_bus_setsig(struct uart_softc *, int);
248 static int uart_pl011_bus_transmit(struct uart_softc *);
249 static void uart_pl011_bus_grab(struct uart_softc *);
250 static void uart_pl011_bus_ungrab(struct uart_softc *);
252 static kobj_method_t uart_pl011_methods[] = {
253 KOBJMETHOD(uart_attach, uart_pl011_bus_attach),
254 KOBJMETHOD(uart_detach, uart_pl011_bus_detach),
255 KOBJMETHOD(uart_flush, uart_pl011_bus_flush),
256 KOBJMETHOD(uart_getsig, uart_pl011_bus_getsig),
257 KOBJMETHOD(uart_ioctl, uart_pl011_bus_ioctl),
258 KOBJMETHOD(uart_ipend, uart_pl011_bus_ipend),
259 KOBJMETHOD(uart_param, uart_pl011_bus_param),
260 KOBJMETHOD(uart_probe, uart_pl011_bus_probe),
261 KOBJMETHOD(uart_receive, uart_pl011_bus_receive),
262 KOBJMETHOD(uart_setsig, uart_pl011_bus_setsig),
263 KOBJMETHOD(uart_transmit, uart_pl011_bus_transmit),
264 KOBJMETHOD(uart_grab, uart_pl011_bus_grab),
265 KOBJMETHOD(uart_ungrab, uart_pl011_bus_ungrab),
270 static struct uart_class uart_pl011_class = {
273 sizeof(struct uart_pl011_softc),
274 .uc_ops = &uart_pl011_ops,
280 static struct ofw_compat_data compat_data[] = {
281 {"arm,pl011", (uintptr_t)&uart_pl011_class},
282 {NULL, (uintptr_t)NULL},
284 UART_FDT_CLASS_AND_DEVICE(compat_data);
287 uart_pl011_bus_attach(struct uart_softc *sc)
289 struct uart_bas *bas;
294 /* Enable interrupts */
295 reg = (UART_RXREADY | RIS_RTIM | UART_TXEMPTY);
296 __uart_setreg(bas, UART_IMSC, reg);
298 /* Clear interrupts */
299 __uart_setreg(bas, UART_ICR, IMSC_MASK_ALL);
305 uart_pl011_bus_detach(struct uart_softc *sc)
312 uart_pl011_bus_flush(struct uart_softc *sc, int what)
319 uart_pl011_bus_getsig(struct uart_softc *sc)
326 uart_pl011_bus_ioctl(struct uart_softc *sc, int request, intptr_t data)
328 struct uart_bas *bas;
333 uart_lock(sc->sc_hwmtx);
335 case UART_IOCTL_BREAK:
337 case UART_IOCTL_BAUD:
338 *(int*)data = 115200;
344 uart_unlock(sc->sc_hwmtx);
350 uart_pl011_bus_ipend(struct uart_softc *sc)
352 struct uart_bas *bas;
358 uart_lock(sc->sc_hwmtx);
359 ints = __uart_getreg(bas, UART_MIS);
362 if (ints & (UART_RXREADY | RIS_RTIM))
363 ipend |= SER_INT_RXREADY;
365 ipend |= SER_INT_BREAK;
367 ipend |= SER_INT_OVERRUN;
368 if (ints & UART_TXEMPTY) {
370 ipend |= SER_INT_TXIDLE;
372 /* Disable TX interrupt */
373 reg = __uart_getreg(bas, UART_IMSC);
374 reg &= ~(UART_TXEMPTY);
375 __uart_setreg(bas, UART_IMSC, reg);
378 uart_unlock(sc->sc_hwmtx);
384 uart_pl011_bus_param(struct uart_softc *sc, int baudrate, int databits,
385 int stopbits, int parity)
388 uart_lock(sc->sc_hwmtx);
389 uart_pl011_param(&sc->sc_bas, baudrate, databits, stopbits, parity);
390 uart_unlock(sc->sc_hwmtx);
396 uart_pl011_bus_probe(struct uart_softc *sc)
399 device_set_desc(sc->sc_dev, "PrimeCell UART (PL011)");
408 uart_pl011_bus_receive(struct uart_softc *sc)
410 struct uart_bas *bas;
415 uart_lock(sc->sc_hwmtx);
417 ints = __uart_getreg(bas, UART_MIS);
418 while (ints & (UART_RXREADY | RIS_RTIM)) {
419 if (uart_rx_full(sc)) {
420 sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN;
423 xc = __uart_getreg(bas, UART_DR);
427 rx |= UART_STAT_FRAMERR;
429 rx |= UART_STAT_PARERR;
431 __uart_setreg(bas, UART_ICR, (UART_RXREADY | RIS_RTIM));
434 ints = __uart_getreg(bas, UART_MIS);
437 uart_unlock(sc->sc_hwmtx);
443 uart_pl011_bus_setsig(struct uart_softc *sc, int sig)
450 uart_pl011_bus_transmit(struct uart_softc *sc)
452 struct uart_bas *bas;
457 uart_lock(sc->sc_hwmtx);
459 for (i = 0; i < sc->sc_txdatasz; i++) {
460 __uart_setreg(bas, UART_DR, sc->sc_txbuf[i]);
464 /* If not empty wait until it is */
465 if ((__uart_getreg(bas, UART_FR) & FR_TXFE) != FR_TXFE) {
468 /* Enable TX interrupt */
469 reg = __uart_getreg(bas, UART_IMSC);
470 reg |= (UART_TXEMPTY);
471 __uart_setreg(bas, UART_IMSC, reg);
474 uart_unlock(sc->sc_hwmtx);
476 /* No interrupt expected, schedule the next fifo write */
478 uart_sched_softih(sc, SER_INT_TXIDLE);
484 uart_pl011_bus_grab(struct uart_softc *sc)
486 struct uart_bas *bas;
489 uart_lock(sc->sc_hwmtx);
490 __uart_setreg(bas, UART_IMSC, /* Switch to RX polling while grabbed */
491 ~UART_RXREADY & __uart_getreg(bas, UART_IMSC));
492 uart_unlock(sc->sc_hwmtx);
496 uart_pl011_bus_ungrab(struct uart_softc *sc)
498 struct uart_bas *bas;
501 uart_lock(sc->sc_hwmtx);
502 __uart_setreg(bas, UART_IMSC, /* Switch to RX interrupts while not grabbed */
503 UART_RXREADY | __uart_getreg(bas, UART_IMSC));
504 uart_unlock(sc->sc_hwmtx);