diff options
author | jhb <jhb@FreeBSD.org> | 2014-07-19 22:13:12 +0000 |
---|---|---|
committer | jhb <jhb@FreeBSD.org> | 2014-07-19 22:13:12 +0000 |
commit | da073828809dcd249ccbc652fb7af05fa0c4d884 (patch) | |
tree | 0ed5805ca5a7c6ff91c28ad15331b3dfb7ff6e9d /usr.sbin | |
parent | 3da9c304ee7b72e7136f1708976a950b3b0a9d41 (diff) | |
download | FreeBSD-src-da073828809dcd249ccbc652fb7af05fa0c4d884.zip FreeBSD-src-da073828809dcd249ccbc652fb7af05fa0c4d884.tar.gz |
MFC 262884,263236,265407:
Various uart fixes:
- Open the uart emulation's backing tty in non-blocking mode.
- Support 16-bit register access.
- Disable the 'uart_drain()' callback when the emulated receive FIFO
is full.
Diffstat (limited to 'usr.sbin')
-rw-r--r-- | usr.sbin/bhyve/pci_lpc.c | 26 | ||||
-rw-r--r-- | usr.sbin/bhyve/uart_emul.c | 131 |
2 files changed, 102 insertions, 55 deletions
diff --git a/usr.sbin/bhyve/pci_lpc.c b/usr.sbin/bhyve/pci_lpc.c index 5b1b4a8..f5e4a69 100644 --- a/usr.sbin/bhyve/pci_lpc.c +++ b/usr.sbin/bhyve/pci_lpc.c @@ -130,15 +130,27 @@ lpc_uart_io_handler(struct vmctx *ctx, int vcpu, int in, int port, int bytes, int offset; struct lpc_uart_softc *sc = arg; - if (bytes != 1) - return (-1); - offset = port - sc->iobase; - if (in) - *eax = uart_read(sc->uart_softc, offset); - else - uart_write(sc->uart_softc, offset, *eax); + switch (bytes) { + case 1: + if (in) + *eax = uart_read(sc->uart_softc, offset); + else + uart_write(sc->uart_softc, offset, *eax); + break; + case 2: + if (in) { + *eax = uart_read(sc->uart_softc, offset); + *eax |= uart_read(sc->uart_softc, offset + 1) << 8; + } else { + uart_write(sc->uart_softc, offset, *eax); + uart_write(sc->uart_softc, offset + 1, *eax >> 8); + } + break; + default: + return (-1); + } return (0); } diff --git a/usr.sbin/bhyve/uart_emul.c b/usr.sbin/bhyve/uart_emul.c index 2fbbd15..ae4cab3 100644 --- a/usr.sbin/bhyve/uart_emul.c +++ b/usr.sbin/bhyve/uart_emul.c @@ -110,6 +110,7 @@ struct uart_softc { uint8_t dlh; /* Baudrate divisor latch MSB */ struct fifo rxfifo; + struct mevent *mev; struct ttyfd tty; bool thre_int_pending; /* THRE interrupt pending */ @@ -145,34 +146,15 @@ ttyopen(struct ttyfd *tf) } } -static bool -tty_char_available(struct ttyfd *tf) -{ - fd_set rfds; - struct timeval tv; - - FD_ZERO(&rfds); - FD_SET(tf->fd, &rfds); - tv.tv_sec = 0; - tv.tv_usec = 0; - if (select(tf->fd + 1, &rfds, NULL, NULL, &tv) > 0 ) { - return (true); - } else { - return (false); - } -} - static int ttyread(struct ttyfd *tf) { - char rb; + unsigned char rb; - if (tty_char_available(tf)) { - read(tf->fd, &rb, 1); - return (rb & 0xff); - } else { + if (read(tf->fd, &rb, 1) == 1) + return (rb); + else return (-1); - } } static void @@ -183,62 +165,111 @@ ttywrite(struct ttyfd *tf, unsigned char wb) } static void -fifo_reset(struct fifo *fifo, int size) +rxfifo_reset(struct uart_softc *sc, int size) { + char flushbuf[32]; + struct fifo *fifo; + ssize_t nread; + int error; + fifo = &sc->rxfifo; bzero(fifo, sizeof(struct fifo)); fifo->size = size; + + if (sc->tty.opened) { + /* + * Flush any unread input from the tty buffer. + */ + while (1) { + nread = read(sc->tty.fd, flushbuf, sizeof(flushbuf)); + if (nread != sizeof(flushbuf)) + break; + } + + /* + * Enable mevent to trigger when new characters are available + * on the tty fd. + */ + error = mevent_enable(sc->mev); + assert(error == 0); + } } static int -fifo_putchar(struct fifo *fifo, uint8_t ch) +rxfifo_available(struct uart_softc *sc) { + struct fifo *fifo; + + fifo = &sc->rxfifo; + return (fifo->num < fifo->size); +} + +static int +rxfifo_putchar(struct uart_softc *sc, uint8_t ch) +{ + struct fifo *fifo; + int error; + + fifo = &sc->rxfifo; if (fifo->num < fifo->size) { fifo->buf[fifo->windex] = ch; fifo->windex = (fifo->windex + 1) % fifo->size; fifo->num++; + if (!rxfifo_available(sc)) { + if (sc->tty.opened) { + /* + * Disable mevent callback if the FIFO is full. + */ + error = mevent_disable(sc->mev); + assert(error == 0); + } + } return (0); } else return (-1); } static int -fifo_getchar(struct fifo *fifo) +rxfifo_getchar(struct uart_softc *sc) { - int c; + struct fifo *fifo; + int c, error, wasfull; + wasfull = 0; + fifo = &sc->rxfifo; if (fifo->num > 0) { + if (!rxfifo_available(sc)) + wasfull = 1; c = fifo->buf[fifo->rindex]; fifo->rindex = (fifo->rindex + 1) % fifo->size; fifo->num--; + if (wasfull) { + if (sc->tty.opened) { + error = mevent_enable(sc->mev); + assert(error == 0); + } + } return (c); } else return (-1); } static int -fifo_numchars(struct fifo *fifo) +rxfifo_numchars(struct uart_softc *sc) { + struct fifo *fifo = &sc->rxfifo; return (fifo->num); } -static int -fifo_available(struct fifo *fifo) -{ - - return (fifo->num < fifo->size); -} - static void uart_opentty(struct uart_softc *sc) { - struct mevent *mev; ttyopen(&sc->tty); - mev = mevent_add(sc->tty.fd, EVF_READ, uart_drain, sc); - assert(mev); + sc->mev = mevent_add(sc->tty.fd, EVF_READ, uart_drain, sc); + assert(sc->mev != NULL); } /* @@ -255,7 +286,7 @@ uart_intr_reason(struct uart_softc *sc) if ((sc->lsr & LSR_OE) != 0 && (sc->ier & IER_ERLS) != 0) return (IIR_RLS); - else if (fifo_numchars(&sc->rxfifo) > 0 && (sc->ier & IER_ERXRDY) != 0) + else if (rxfifo_numchars(sc) > 0 && (sc->ier & IER_ERXRDY) != 0) return (IIR_RXTOUT); else if (sc->thre_int_pending && (sc->ier & IER_ETXRDY) != 0) return (IIR_TXRDY); @@ -274,7 +305,7 @@ uart_reset(struct uart_softc *sc) sc->dll = divisor; sc->dlh = divisor >> 16; - fifo_reset(&sc->rxfifo, 1); /* no fifo until enabled by software */ + rxfifo_reset(sc, 1); /* no fifo until enabled by software */ } /* @@ -315,9 +346,9 @@ uart_drain(int fd, enum ev_type ev, void *arg) if ((sc->mcr & MCR_LOOPBACK) != 0) { (void) ttyread(&sc->tty); } else { - while (fifo_available(&sc->rxfifo) && + while (rxfifo_available(sc) && ((ch = ttyread(&sc->tty)) != -1)) { - fifo_putchar(&sc->rxfifo, ch); + rxfifo_putchar(sc, ch); } uart_toggle_intr(sc); } @@ -351,7 +382,7 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value) switch (offset) { case REG_DATA: if (sc->mcr & MCR_LOOPBACK) { - if (fifo_putchar(&sc->rxfifo, value) != 0) + if (rxfifo_putchar(sc, value) != 0) sc->lsr |= LSR_OE; } else if (sc->tty.opened) { ttywrite(&sc->tty, value); @@ -372,7 +403,7 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value) */ if ((sc->fcr & FCR_ENABLE) ^ (value & FCR_ENABLE)) { fifosz = (value & FCR_ENABLE) ? FIFOSZ : 1; - fifo_reset(&sc->rxfifo, fifosz); + rxfifo_reset(sc, fifosz); } /* @@ -383,7 +414,7 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value) sc->fcr = 0; } else { if ((value & FCR_RCV_RST) != 0) - fifo_reset(&sc->rxfifo, FIFOSZ); + rxfifo_reset(sc, FIFOSZ); sc->fcr = value & (FCR_ENABLE | FCR_DMA | FCR_RX_MASK); @@ -480,7 +511,7 @@ uart_read(struct uart_softc *sc, int offset) switch (offset) { case REG_DATA: - reg = fifo_getchar(&sc->rxfifo); + reg = rxfifo_getchar(sc); break; case REG_IER: reg = sc->ier; @@ -511,7 +542,7 @@ uart_read(struct uart_softc *sc, int offset) sc->lsr |= LSR_TEMT | LSR_THRE; /* Check for new receive data */ - if (fifo_numchars(&sc->rxfifo) > 0) + if (rxfifo_numchars(sc) > 0) sc->lsr |= LSR_RXRDY; else sc->lsr &= ~LSR_RXRDY; @@ -585,7 +616,7 @@ uart_tty_backend(struct uart_softc *sc, const char *opts) retval = -1; - fd = open(opts, O_RDWR); + fd = open(opts, O_RDWR | O_NONBLOCK); if (fd > 0 && isatty(fd)) { sc->tty.fd = fd; sc->tty.opened = true; @@ -616,6 +647,10 @@ uart_set_backend(struct uart_softc *sc, const char *opts) retval = 0; } + /* Make the backend file descriptor non-blocking */ + if (retval == 0) + retval = fcntl(sc->tty.fd, F_SETFL, O_NONBLOCK); + if (retval == 0) uart_opentty(sc); |