/*- * Copyright (c) 2012 Semihalf. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include "uart_if.h" #include /* PL011 UART registers and masks*/ #define UART_DR 0x00 /* Data register */ #define DR_FE (1 << 8) /* Framing error */ #define DR_PE (1 << 9) /* Parity error */ #define DR_BE (1 << 10) /* Break error */ #define DR_OE (1 << 11) /* Overrun error */ #define UART_FR 0x06 /* Flag register */ #define FR_TXFF (1 << 5) /* Transmit FIFO/reg full */ #define FR_RXFF (1 << 6) /* Receive FIFO/reg full */ #define FR_TXFE (1 << 7) /* Transmit FIFO/reg empty */ #define UART_IBRD 0x09 /* Integer baud rate register */ #define IBRD_BDIVINT 0xffff /* Significant part of int. divisor value */ #define UART_FBRD 0x0a /* Fractional baud rate register */ #define FBRD_BDIVFRAC 0x3f /* Significant part of frac. divisor value */ #define UART_LCR_H 0x0b /* Line control register */ #define LCR_H_WLEN8 (0x3 << 5) #define LCR_H_WLEN7 (0x2 << 5) #define LCR_H_WLEN6 (0x1 << 5) #define LCR_H_FEN (1 << 4) /* FIFO mode enable */ #define LCR_H_STP2 (1 << 3) /* 2 stop frames at the end */ #define LCR_H_EPS (1 << 2) /* Even parity select */ #define LCR_H_PEN (1 << 1) /* Parity enable */ #define UART_CR 0x0c /* Control register */ #define CR_RXE (1 << 9) /* Receive enable */ #define CR_TXE (1 << 8) /* Transmit enable */ #define CR_UARTEN (1 << 0) /* UART enable */ #define UART_IMSC 0x0e /* Interrupt mask set/clear register */ #define IMSC_MASK_ALL 0x7ff /* Mask all interrupts */ #define UART_RIS 0x0f /* Raw interrupt status register */ #define UART_RXREADY (1 << 4) /* RX buffer full */ #define UART_TXEMPTY (1 << 5) /* TX buffer empty */ #define RIS_RTIM (1 << 6) /* Receive timeout */ #define RIS_FE (1 << 7) /* Framing error interrupt status */ #define RIS_PE (1 << 8) /* Parity error interrupt status */ #define RIS_BE (1 << 9) /* Break error interrupt status */ #define RIS_OE (1 << 10) /* Overrun interrupt status */ #define UART_MIS 0x10 /* Masked interrupt status register */ #define UART_ICR 0x11 /* Interrupt clear register */ /* * FIXME: actual register size is SoC-dependent, we need to handle it */ #define __uart_getreg(bas, reg) \ bus_space_read_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg)) #define __uart_setreg(bas, reg, value) \ bus_space_write_4((bas)->bst, (bas)->bsh, uart_regofs(bas, reg), value) /* * Low-level UART interface. */ static int uart_pl011_probe(struct uart_bas *bas); static void uart_pl011_init(struct uart_bas *bas, int, int, int, int); static void uart_pl011_term(struct uart_bas *bas); static void uart_pl011_putc(struct uart_bas *bas, int); static int uart_pl011_rxready(struct uart_bas *bas); static int uart_pl011_getc(struct uart_bas *bas, struct mtx *); static struct uart_ops uart_pl011_ops = { .probe = uart_pl011_probe, .init = uart_pl011_init, .term = uart_pl011_term, .putc = uart_pl011_putc, .rxready = uart_pl011_rxready, .getc = uart_pl011_getc, }; static int uart_pl011_probe(struct uart_bas *bas) { return (0); } static void uart_pl011_param(struct uart_bas *bas, int baudrate, int databits, int stopbits, int parity) { uint32_t ctrl, line; uint32_t baud; /* * Zero all settings to make sure * UART is disabled and not configured */ ctrl = line = 0x0; __uart_setreg(bas, UART_CR, ctrl); /* As we know UART is disabled we may setup the line */ switch (databits) { case 7: line |= LCR_H_WLEN7; break; case 6: line |= LCR_H_WLEN6; break; case 8: default: line |= LCR_H_WLEN8; break; } if (stopbits == 2) line |= LCR_H_STP2; else line &= ~LCR_H_STP2; if (parity) line |= LCR_H_PEN; else line &= ~LCR_H_PEN; /* Configure the rest */ line &= ~LCR_H_FEN; ctrl |= (CR_RXE | CR_TXE | CR_UARTEN); if (bas->rclk != 0 && baudrate != 0) { baud = bas->rclk * 4 / baudrate; __uart_setreg(bas, UART_IBRD, ((uint32_t)(baud >> 6)) & IBRD_BDIVINT); __uart_setreg(bas, UART_FBRD, (uint32_t)(baud & 0x3F) & FBRD_BDIVFRAC); } /* Add config. to line before reenabling UART */ __uart_setreg(bas, UART_LCR_H, (__uart_getreg(bas, UART_LCR_H) & ~0xff) | line); __uart_setreg(bas, UART_CR, ctrl); } static void uart_pl011_init(struct uart_bas *bas, int baudrate, int databits, int stopbits, int parity) { /* Mask all interrupts */ __uart_setreg(bas, UART_IMSC, __uart_getreg(bas, UART_IMSC) & ~IMSC_MASK_ALL); uart_pl011_param(bas, baudrate, databits, stopbits, parity); } static void uart_pl011_term(struct uart_bas *bas) { } static void uart_pl011_putc(struct uart_bas *bas, int c) { /* Wait when TX FIFO full. Push character otherwise. */ while (__uart_getreg(bas, UART_FR) & FR_TXFF) ; __uart_setreg(bas, UART_DR, c & 0xff); } static int uart_pl011_rxready(struct uart_bas *bas) { return (__uart_getreg(bas, UART_FR) & FR_RXFF); } static int uart_pl011_getc(struct uart_bas *bas, struct mtx *hwmtx) { int c; while (!uart_pl011_rxready(bas)) ; c = __uart_getreg(bas, UART_DR) & 0xff; return (c); } /* * High-level UART interface. */ struct uart_pl011_softc { struct uart_softc base; uint8_t fcr; uint8_t ier; uint8_t mcr; uint8_t ier_mask; uint8_t ier_rxbits; }; static int uart_pl011_bus_attach(struct uart_softc *); static int uart_pl011_bus_detach(struct uart_softc *); static int uart_pl011_bus_flush(struct uart_softc *, int); static int uart_pl011_bus_getsig(struct uart_softc *); static int uart_pl011_bus_ioctl(struct uart_softc *, int, intptr_t); static int uart_pl011_bus_ipend(struct uart_softc *); static int uart_pl011_bus_param(struct uart_softc *, int, int, int, int); static int uart_pl011_bus_probe(struct uart_softc *); static int uart_pl011_bus_receive(struct uart_softc *); static int uart_pl011_bus_setsig(struct uart_softc *, int); static int uart_pl011_bus_transmit(struct uart_softc *); static void uart_pl011_bus_grab(struct uart_softc *); static void uart_pl011_bus_ungrab(struct uart_softc *); static kobj_method_t uart_pl011_methods[] = { KOBJMETHOD(uart_attach, uart_pl011_bus_attach), KOBJMETHOD(uart_detach, uart_pl011_bus_detach), KOBJMETHOD(uart_flush, uart_pl011_bus_flush), KOBJMETHOD(uart_getsig, uart_pl011_bus_getsig), KOBJMETHOD(uart_ioctl, uart_pl011_bus_ioctl), KOBJMETHOD(uart_ipend, uart_pl011_bus_ipend), KOBJMETHOD(uart_param, uart_pl011_bus_param), KOBJMETHOD(uart_probe, uart_pl011_bus_probe), KOBJMETHOD(uart_receive, uart_pl011_bus_receive), KOBJMETHOD(uart_setsig, uart_pl011_bus_setsig), KOBJMETHOD(uart_transmit, uart_pl011_bus_transmit), KOBJMETHOD(uart_grab, uart_pl011_bus_grab), KOBJMETHOD(uart_ungrab, uart_pl011_bus_ungrab), { 0, 0 } }; static struct uart_class uart_pl011_class = { "uart_pl011", uart_pl011_methods, sizeof(struct uart_pl011_softc), .uc_ops = &uart_pl011_ops, .uc_range = 0x48, .uc_rclk = 0 }; static struct ofw_compat_data compat_data[] = { {"arm,pl011", (uintptr_t)&uart_pl011_class}, {NULL, (uintptr_t)NULL}, }; UART_FDT_CLASS_AND_DEVICE(compat_data); static int uart_pl011_bus_attach(struct uart_softc *sc) { struct uart_bas *bas; int reg; bas = &sc->sc_bas; /* Enable interrupts */ reg = (UART_RXREADY | RIS_RTIM | UART_TXEMPTY); __uart_setreg(bas, UART_IMSC, reg); /* Clear interrupts */ __uart_setreg(bas, UART_ICR, IMSC_MASK_ALL); return (0); } static int uart_pl011_bus_detach(struct uart_softc *sc) { return (0); } static int uart_pl011_bus_flush(struct uart_softc *sc, int what) { return (0); } static int uart_pl011_bus_getsig(struct uart_softc *sc) { return (0); } static int uart_pl011_bus_ioctl(struct uart_softc *sc, int request, intptr_t data) { struct uart_bas *bas; int error; bas = &sc->sc_bas; error = 0; uart_lock(sc->sc_hwmtx); switch (request) { case UART_IOCTL_BREAK: break; case UART_IOCTL_BAUD: *(int*)data = 115200; break; default: error = EINVAL; break; } uart_unlock(sc->sc_hwmtx); return (error); } static int uart_pl011_bus_ipend(struct uart_softc *sc) { struct uart_bas *bas; uint32_t ints; int ipend; int reg; bas = &sc->sc_bas; uart_lock(sc->sc_hwmtx); ints = __uart_getreg(bas, UART_MIS); ipend = 0; if (ints & (UART_RXREADY | RIS_RTIM)) ipend |= SER_INT_RXREADY; if (ints & RIS_BE) ipend |= SER_INT_BREAK; if (ints & RIS_OE) ipend |= SER_INT_OVERRUN; if (ints & UART_TXEMPTY) { if (sc->sc_txbusy) ipend |= SER_INT_TXIDLE; /* Disable TX interrupt */ reg = __uart_getreg(bas, UART_IMSC); reg &= ~(UART_TXEMPTY); __uart_setreg(bas, UART_IMSC, reg); } uart_unlock(sc->sc_hwmtx); return (ipend); } static int uart_pl011_bus_param(struct uart_softc *sc, int baudrate, int databits, int stopbits, int parity) { uart_lock(sc->sc_hwmtx); uart_pl011_param(&sc->sc_bas, baudrate, databits, stopbits, parity); uart_unlock(sc->sc_hwmtx); return (0); } static int uart_pl011_bus_probe(struct uart_softc *sc) { device_set_desc(sc->sc_dev, "PrimeCell UART (PL011)"); sc->sc_rxfifosz = 1; sc->sc_txfifosz = 1; return (0); } static int uart_pl011_bus_receive(struct uart_softc *sc) { struct uart_bas *bas; uint32_t ints, xc; int rx; bas = &sc->sc_bas; uart_lock(sc->sc_hwmtx); ints = __uart_getreg(bas, UART_MIS); while (ints & (UART_RXREADY | RIS_RTIM)) { if (uart_rx_full(sc)) { sc->sc_rxbuf[sc->sc_rxput] = UART_STAT_OVERRUN; break; } xc = __uart_getreg(bas, UART_DR); rx = xc & 0xff; if (xc & DR_FE) rx |= UART_STAT_FRAMERR; if (xc & DR_PE) rx |= UART_STAT_PARERR; __uart_setreg(bas, UART_ICR, (UART_RXREADY | RIS_RTIM)); uart_rx_put(sc, rx); ints = __uart_getreg(bas, UART_MIS); } uart_unlock(sc->sc_hwmtx); return (0); } static int uart_pl011_bus_setsig(struct uart_softc *sc, int sig) { return (0); } static int uart_pl011_bus_transmit(struct uart_softc *sc) { struct uart_bas *bas; int reg; int i; bas = &sc->sc_bas; uart_lock(sc->sc_hwmtx); for (i = 0; i < sc->sc_txdatasz; i++) { __uart_setreg(bas, UART_DR, sc->sc_txbuf[i]); uart_barrier(bas); } sc->sc_txbusy = 1; /* Enable TX interrupt */ reg = __uart_getreg(bas, UART_IMSC); reg |= (UART_TXEMPTY); __uart_setreg(bas, UART_IMSC, reg); uart_unlock(sc->sc_hwmtx); return (0); } static void uart_pl011_bus_grab(struct uart_softc *sc) { struct uart_bas *bas; bas = &sc->sc_bas; uart_lock(sc->sc_hwmtx); __uart_setreg(bas, UART_IMSC, /* Switch to RX polling while grabbed */ ~UART_RXREADY & __uart_getreg(bas, UART_IMSC)); uart_unlock(sc->sc_hwmtx); } static void uart_pl011_bus_ungrab(struct uart_softc *sc) { struct uart_bas *bas; bas = &sc->sc_bas; uart_lock(sc->sc_hwmtx); __uart_setreg(bas, UART_IMSC, /* Switch to RX interrupts while not grabbed */ UART_RXREADY | __uart_getreg(bas, UART_IMSC)); uart_unlock(sc->sc_hwmtx); }