git: 2b4745d2c193 - stable/14 - bhyve: Move device model-independent UART code into a separate file
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Date: Fri, 29 Mar 2024 18:11:55 UTC
The branch stable/14 has been updated by markj:
URL: https://cgit.FreeBSD.org/src/commit/?id=2b4745d2c193bede4b887f882e302c02c1f300ef
commit 2b4745d2c193bede4b887f882e302c02c1f300ef
Author: Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2024-03-21 04:20:37 +0000
Commit: Mark Johnston <markj@FreeBSD.org>
CommitDate: 2024-03-29 13:53:28 +0000
bhyve: Move device model-independent UART code into a separate file
Currently bhyve implements a ns16550-compatible UART in uart_emul.c.
This file also contains generic code to manage RX FIFOs and to handle
reading from and writing to a TTY. bhyve instantiates UARTs to
implement COM devices (via pci_lpc.c) and PCI UART devices.
The arm64 port will bring with it a PL011 device model which is used as
the default console (i.e., no COM ports). To simplify its integration,
add a UART "backend" layer which lets UART device models allocate an RX
FIFO and interact with TTYs without duplicating code. In particular,
code in uart_backend.* is to be shared among device models, and the
namespace for uart_emul.* is changed to uart_ns16550_*.
This is based on andrew@'s work in
https://github.com/zxombie/freebsd/tree/bhyvearm64 but I've made a
number of changes, particularly with respect to naming and source code
organization.
No functional change intended.
Reviewed by: corvink, jhb
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40993
(cherry picked from commit d1c5d0cfcc1733c243d87f20477b115db4cf24b6)
---
usr.sbin/bhyve/Makefile | 1 +
usr.sbin/bhyve/amd64/pci_lpc.c | 31 ++--
usr.sbin/bhyve/pci_uart.c | 13 +-
usr.sbin/bhyve/uart_backend.c | 348 +++++++++++++++++++++++++++++++++++++++++
usr.sbin/bhyve/uart_backend.h | 55 +++++++
usr.sbin/bhyve/uart_emul.c | 344 +++++-----------------------------------
usr.sbin/bhyve/uart_emul.h | 20 ++-
7 files changed, 478 insertions(+), 334 deletions(-)
diff --git a/usr.sbin/bhyve/Makefile b/usr.sbin/bhyve/Makefile
index c9d571daebbc..03ea77769754 100644
--- a/usr.sbin/bhyve/Makefile
+++ b/usr.sbin/bhyve/Makefile
@@ -56,6 +56,7 @@ SRCS= \
tpm_emul_passthru.c \
tpm_intf_crb.c \
tpm_ppi_qemu.c \
+ uart_backend.c \
uart_emul.c \
usb_emul.c \
usb_mouse.c \
diff --git a/usr.sbin/bhyve/amd64/pci_lpc.c b/usr.sbin/bhyve/amd64/pci_lpc.c
index 5c2a2a7965b0..c29fd115809d 100644
--- a/usr.sbin/bhyve/amd64/pci_lpc.c
+++ b/usr.sbin/bhyve/amd64/pci_lpc.c
@@ -70,7 +70,7 @@ static struct pci_devinst *lpc_bridge;
#define LPC_UART_NUM 4
static struct lpc_uart_softc {
- struct uart_softc *uart_softc;
+ struct uart_ns16550_softc *uart_softc;
int iobase;
int irq;
int enabled;
@@ -227,17 +227,19 @@ lpc_uart_io_handler(struct vmctx *ctx __unused, int in,
switch (bytes) {
case 1:
if (in)
- *eax = uart_read(sc->uart_softc, offset);
+ *eax = uart_ns16550_read(sc->uart_softc, offset);
else
- uart_write(sc->uart_softc, offset, *eax);
+ uart_ns16550_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;
+ *eax = uart_ns16550_read(sc->uart_softc, offset);
+ *eax |=
+ uart_ns16550_read(sc->uart_softc, offset + 1) << 8;
} else {
- uart_write(sc->uart_softc, offset, *eax);
- uart_write(sc->uart_softc, offset + 1, *eax >> 8);
+ uart_ns16550_write(sc->uart_softc, offset, *eax);
+ uart_ns16550_write(sc->uart_softc, offset + 1,
+ *eax >> 8);
}
break;
default:
@@ -276,13 +278,14 @@ lpc_init(struct vmctx *ctx)
}
pci_irq_reserve(sc->irq);
- sc->uart_softc = uart_init(lpc_uart_intr_assert,
- lpc_uart_intr_deassert, sc);
+ sc->uart_softc = uart_ns16550_init(lpc_uart_intr_assert,
+ lpc_uart_intr_deassert, sc);
asprintf(&node_name, "lpc.%s.path", name);
backend = get_config_value(node_name);
free(node_name);
- if (uart_set_backend(sc->uart_softc, backend) != 0) {
+ if (backend != NULL &&
+ uart_ns16550_tty_open(sc->uart_softc, backend) != 0) {
EPRINTLN("Unable to initialize backend '%s' "
"for LPC device %s", backend, name);
return (-1);
@@ -291,7 +294,7 @@ lpc_init(struct vmctx *ctx)
bzero(&iop, sizeof(struct inout_port));
iop.name = name;
iop.port = sc->iobase;
- iop.size = UART_IO_BAR_SIZE;
+ iop.size = UART_NS16550_IO_BAR_SIZE;
iop.flags = IOPORT_F_INOUT;
iop.handler = lpc_uart_io_handler;
iop.arg = sc;
@@ -424,7 +427,7 @@ pci_lpc_uart_dsdt(void)
dsdt_line(" Name (_CRS, ResourceTemplate ()");
dsdt_line(" {");
dsdt_indent(2);
- dsdt_fixed_ioport(sc->iobase, UART_IO_BAR_SIZE);
+ dsdt_fixed_ioport(sc->iobase, UART_NS16550_IO_BAR_SIZE);
dsdt_fixed_irq(sc->irq);
dsdt_unindent(2);
dsdt_line(" })");
@@ -589,12 +592,12 @@ static int
pci_lpc_snapshot(struct vm_snapshot_meta *meta)
{
int unit, ret;
- struct uart_softc *sc;
+ struct uart_ns16550_softc *sc;
for (unit = 0; unit < LPC_UART_NUM; unit++) {
sc = lpc_uart_softc[unit].uart_softc;
- ret = uart_snapshot(sc, meta);
+ ret = uart_ns16550_snapshot(sc, meta);
if (ret != 0)
goto done;
}
diff --git a/usr.sbin/bhyve/pci_uart.c b/usr.sbin/bhyve/pci_uart.c
index 362238bf3168..1e5278ba4d59 100644
--- a/usr.sbin/bhyve/pci_uart.c
+++ b/usr.sbin/bhyve/pci_uart.c
@@ -68,7 +68,7 @@ pci_uart_write(struct pci_devinst *pi, int baridx, uint64_t offset, int size,
assert(baridx == 0);
assert(size == 1);
- uart_write(pi->pi_arg, offset, value);
+ uart_ns16550_write(pi->pi_arg, offset, value);
}
static uint64_t
@@ -79,7 +79,7 @@ pci_uart_read(struct pci_devinst *pi, int baridx, uint64_t offset, int size)
assert(baridx == 0);
assert(size == 1);
- val = uart_read(pi->pi_arg, offset);
+ val = uart_ns16550_read(pi->pi_arg, offset);
return (val);
}
@@ -95,10 +95,10 @@ pci_uart_legacy_config(nvlist_t *nvl, const char *opts)
static int
pci_uart_init(struct pci_devinst *pi, nvlist_t *nvl)
{
- struct uart_softc *sc;
+ struct uart_ns16550_softc *sc;
const char *device;
- pci_emul_alloc_bar(pi, 0, PCIBAR_IO, UART_IO_BAR_SIZE);
+ pci_emul_alloc_bar(pi, 0, PCIBAR_IO, UART_NS16550_IO_BAR_SIZE);
pci_lintr_request(pi);
/* initialize config space */
@@ -106,11 +106,12 @@ pci_uart_init(struct pci_devinst *pi, nvlist_t *nvl)
pci_set_cfgdata16(pi, PCIR_VENDOR, COM_VENDOR);
pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_SIMPLECOMM);
- sc = uart_init(pci_uart_intr_assert, pci_uart_intr_deassert, pi);
+ sc = uart_ns16550_init(pci_uart_intr_assert, pci_uart_intr_deassert,
+ pi);
pi->pi_arg = sc;
device = get_config_value_node(nvl, "path");
- if (uart_set_backend(sc, device) != 0) {
+ if (device != NULL && uart_ns16550_tty_open(sc, device) != 0) {
EPRINTLN("Unable to initialize backend '%s' for "
"pci uart at %d:%d", device, pi->pi_slot, pi->pi_func);
return (-1);
diff --git a/usr.sbin/bhyve/uart_backend.c b/usr.sbin/bhyve/uart_backend.c
new file mode 100644
index 000000000000..8d91f4f671e1
--- /dev/null
+++ b/usr.sbin/bhyve/uart_backend.c
@@ -0,0 +1,348 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2012 NetApp, Inc.
+ * Copyright (c) 2013 Neel Natu <neel@freebsd.org>
+ * 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 NETAPP, INC ``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 NETAPP, INC 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 <sys/types.h>
+
+#include <machine/vmm.h>
+#include <machine/vmm_snapshot.h>
+
+#include <assert.h>
+#include <capsicum_helpers.h>
+#include <err.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sysexits.h>
+#include <termios.h>
+#include <unistd.h>
+
+#include "debug.h"
+#include "mevent.h"
+#include "uart_backend.h"
+
+struct ttyfd {
+ bool opened;
+ int rfd; /* fd for reading */
+ int wfd; /* fd for writing, may be == rfd */
+};
+
+#define FIFOSZ 16
+
+struct fifo {
+ uint8_t buf[FIFOSZ];
+ int rindex; /* index to read from */
+ int windex; /* index to write to */
+ int num; /* number of characters in the fifo */
+ int size; /* size of the fifo */
+};
+
+struct uart_softc {
+ struct ttyfd tty;
+ struct fifo rxfifo;
+ struct mevent *mev;
+};
+
+static bool uart_stdio; /* stdio in use for i/o */
+static struct termios tio_stdio_orig;
+
+static void
+ttyclose(void)
+{
+ tcsetattr(STDIN_FILENO, TCSANOW, &tio_stdio_orig);
+}
+
+static void
+ttyopen(struct ttyfd *tf)
+{
+ struct termios orig, new;
+
+ tcgetattr(tf->rfd, &orig);
+ new = orig;
+ cfmakeraw(&new);
+ new.c_cflag |= CLOCAL;
+ tcsetattr(tf->rfd, TCSANOW, &new);
+ if (uart_stdio) {
+ tio_stdio_orig = orig;
+ atexit(ttyclose);
+ }
+ raw_stdio = 1;
+}
+
+static int
+ttyread(struct ttyfd *tf)
+{
+ unsigned char rb;
+
+ if (read(tf->rfd, &rb, 1) == 1)
+ return (rb);
+ else
+ return (-1);
+}
+
+static void
+ttywrite(struct ttyfd *tf, unsigned char wb)
+{
+ (void)write(tf->wfd, &wb, 1);
+}
+
+static bool
+rxfifo_available(struct uart_softc *sc)
+{
+ return (sc->rxfifo.num < sc->rxfifo.size);
+}
+
+int
+uart_rxfifo_getchar(struct uart_softc *sc)
+{
+ 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);
+}
+
+int
+uart_rxfifo_numchars(struct uart_softc *sc)
+{
+ return (sc->rxfifo.num);
+}
+
+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);
+}
+
+void
+uart_rxfifo_drain(struct uart_softc *sc, bool loopback)
+{
+ int ch;
+
+ if (loopback) {
+ (void)ttyread(&sc->tty);
+ } else {
+ while (rxfifo_available(sc) &&
+ ((ch = ttyread(&sc->tty)) != -1))
+ rxfifo_putchar(sc, ch);
+ }
+}
+
+int
+uart_rxfifo_putchar(struct uart_softc *sc, uint8_t ch, bool loopback)
+{
+ if (loopback) {
+ return (rxfifo_putchar(sc, ch));
+ } else if (sc->tty.opened) {
+ ttywrite(&sc->tty, ch);
+ return (0);
+ } else {
+ /* Drop on the floor. */
+ return (0);
+ }
+}
+
+void
+uart_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.rfd, 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);
+ }
+}
+
+int
+uart_rxfifo_size(struct uart_softc *sc __unused)
+{
+ return (FIFOSZ);
+}
+
+#ifdef BHYVE_SNAPSHOT
+int
+uart_rxfifo_snapshot(struct uart_softc *sc, struct vm_snapshot_meta *meta)
+{
+ int ret;
+
+ SNAPSHOT_VAR_OR_LEAVE(sc->rxfifo.rindex, meta, ret, done);
+ SNAPSHOT_VAR_OR_LEAVE(sc->rxfifo.windex, meta, ret, done);
+ SNAPSHOT_VAR_OR_LEAVE(sc->rxfifo.num, meta, ret, done);
+ SNAPSHOT_VAR_OR_LEAVE(sc->rxfifo.size, meta, ret, done);
+ SNAPSHOT_BUF_OR_LEAVE(sc->rxfifo.buf, sizeof(sc->rxfifo.buf),
+ meta, ret, done);
+
+done:
+ return (ret);
+}
+#endif
+
+static int
+uart_stdio_backend(struct uart_softc *sc)
+{
+#ifndef WITHOUT_CAPSICUM
+ cap_rights_t rights;
+ cap_ioctl_t cmds[] = { TIOCGETA, TIOCSETA, TIOCGWINSZ };
+#endif
+
+ if (uart_stdio)
+ return (-1);
+
+ sc->tty.rfd = STDIN_FILENO;
+ sc->tty.wfd = STDOUT_FILENO;
+ sc->tty.opened = true;
+
+ if (fcntl(sc->tty.rfd, F_SETFL, O_NONBLOCK) != 0)
+ return (-1);
+ if (fcntl(sc->tty.wfd, F_SETFL, O_NONBLOCK) != 0)
+ return (-1);
+
+#ifndef WITHOUT_CAPSICUM
+ cap_rights_init(&rights, CAP_EVENT, CAP_IOCTL, CAP_READ);
+ if (caph_rights_limit(sc->tty.rfd, &rights) == -1)
+ errx(EX_OSERR, "Unable to apply rights for sandbox");
+ if (caph_ioctls_limit(sc->tty.rfd, cmds, nitems(cmds)) == -1)
+ errx(EX_OSERR, "Unable to apply rights for sandbox");
+#endif
+
+ uart_stdio = true;
+
+ return (0);
+}
+
+static int
+uart_tty_backend(struct uart_softc *sc, const char *path)
+{
+#ifndef WITHOUT_CAPSICUM
+ cap_rights_t rights;
+ cap_ioctl_t cmds[] = { TIOCGETA, TIOCSETA, TIOCGWINSZ };
+#endif
+ int fd;
+
+ fd = open(path, O_RDWR | O_NONBLOCK);
+ if (fd < 0)
+ return (-1);
+
+ if (!isatty(fd)) {
+ close(fd);
+ return (-1);
+ }
+
+ sc->tty.rfd = sc->tty.wfd = fd;
+ sc->tty.opened = true;
+
+#ifndef WITHOUT_CAPSICUM
+ cap_rights_init(&rights, CAP_EVENT, CAP_IOCTL, CAP_READ, CAP_WRITE);
+ if (caph_rights_limit(fd, &rights) == -1)
+ errx(EX_OSERR, "Unable to apply rights for sandbox");
+ if (caph_ioctls_limit(fd, cmds, nitems(cmds)) == -1)
+ errx(EX_OSERR, "Unable to apply rights for sandbox");
+#endif
+
+ return (0);
+}
+
+struct uart_softc *
+uart_init(void)
+{
+ return (calloc(1, sizeof(struct uart_softc)));
+}
+
+int
+uart_tty_open(struct uart_softc *sc, const char *path,
+ void (*drain)(int, enum ev_type, void *), void *arg)
+{
+ int retval;
+
+ if (strcmp("stdio", path) == 0)
+ retval = uart_stdio_backend(sc);
+ else
+ retval = uart_tty_backend(sc, path);
+ if (retval == 0) {
+ ttyopen(&sc->tty);
+ sc->mev = mevent_add(sc->tty.rfd, EVF_READ, drain, arg);
+ assert(sc->mev != NULL);
+ }
+
+ return (retval);
+}
diff --git a/usr.sbin/bhyve/uart_backend.h b/usr.sbin/bhyve/uart_backend.h
new file mode 100644
index 000000000000..fa7949ad6d1c
--- /dev/null
+++ b/usr.sbin/bhyve/uart_backend.h
@@ -0,0 +1,55 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2012 NetApp, Inc.
+ * Copyright (c) 2013 Neel Natu <neel@freebsd.org>
+ * 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 NETAPP, INC ``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 NETAPP, INC 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.
+ */
+
+#ifndef _UART_BACKEND_H_
+#define _UART_BACKEND_H_
+
+#include <stdbool.h>
+
+#include "mevent.h"
+
+struct uart_softc;
+struct vm_snapshot_meta;
+
+void uart_rxfifo_drain(struct uart_softc *sc, bool loopback);
+int uart_rxfifo_getchar(struct uart_softc *sc);
+int uart_rxfifo_numchars(struct uart_softc *sc);
+int uart_rxfifo_putchar(struct uart_softc *sc, uint8_t ch, bool loopback);
+void uart_rxfifo_reset(struct uart_softc *sc, int size);
+int uart_rxfifo_size(struct uart_softc *sc);
+#ifdef BHYVE_SNAPSHOT
+int uart_rxfifo_snapshot(struct uart_softc *sc,
+ struct vm_snapshot_meta *meta);
+#endif
+
+struct uart_softc *uart_init(void);
+int uart_tty_open(struct uart_softc *sc, const char *path,
+ void (*drain)(int, enum ev_type, void *), void *arg);
+
+#endif /* _UART_BACKEND_H_ */
diff --git a/usr.sbin/bhyve/uart_emul.c b/usr.sbin/bhyve/uart_emul.c
index 917ce36b67f6..05f552021bbf 100644
--- a/usr.sbin/bhyve/uart_emul.c
+++ b/usr.sbin/bhyve/uart_emul.c
@@ -30,29 +30,20 @@
#include <sys/cdefs.h>
#include <sys/types.h>
#include <dev/ic/ns16550.h>
-#ifndef WITHOUT_CAPSICUM
-#include <sys/capsicum.h>
-#include <capsicum_helpers.h>
-#endif
#include <machine/vmm_snapshot.h>
+#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
-#include <assert.h>
-#include <err.h>
#include <errno.h>
-#include <fcntl.h>
-#include <termios.h>
#include <unistd.h>
#include <stdbool.h>
#include <string.h>
#include <pthread.h>
-#include <sysexits.h>
-#include "mevent.h"
+#include "uart_backend.h"
#include "uart_emul.h"
-#include "debug.h"
#define COM1_BASE 0x3F8
#define COM1_IRQ 4
@@ -77,11 +68,6 @@
#define REG_SCR com_scr
#endif
-#define FIFOSZ 16
-
-static bool uart_stdio; /* stdio in use for i/o */
-static struct termios tio_stdio_orig;
-
static struct {
int baseaddr;
int irq;
@@ -95,21 +81,9 @@ static struct {
#define UART_NLDEVS (sizeof(uart_lres) / sizeof(uart_lres[0]))
-struct fifo {
- uint8_t buf[FIFOSZ];
- int rindex; /* index to read from */
- int windex; /* index to write to */
- int num; /* number of characters in the fifo */
- int size; /* size of the fifo */
-};
-
-struct ttyfd {
- bool opened;
- int rfd; /* fd for reading */
- int wfd; /* fd for writing, may be == rfd */
-};
+struct uart_ns16550_softc {
+ struct uart_softc *backend;
-struct uart_softc {
pthread_mutex_t mtx; /* protects all softc elements */
uint8_t data; /* Data register (R/W) */
uint8_t ier; /* Interrupt enable register (R/W) */
@@ -123,10 +97,6 @@ struct uart_softc {
uint8_t dll; /* Baudrate divisor latch LSB */
uint8_t dlh; /* Baudrate divisor latch MSB */
- struct fifo rxfifo;
- struct mevent *mev;
-
- struct ttyfd tty;
bool thre_int_pending; /* THRE interrupt pending */
void *arg;
@@ -134,158 +104,6 @@ struct uart_softc {
uart_intr_func_t intr_deassert;
};
-static void uart_drain(int fd, enum ev_type ev, void *arg);
-
-static void
-ttyclose(void)
-{
-
- tcsetattr(STDIN_FILENO, TCSANOW, &tio_stdio_orig);
-}
-
-static void
-ttyopen(struct ttyfd *tf)
-{
- struct termios orig, new;
-
- tcgetattr(tf->rfd, &orig);
- new = orig;
- cfmakeraw(&new);
- new.c_cflag |= CLOCAL;
- tcsetattr(tf->rfd, TCSANOW, &new);
- if (uart_stdio) {
- tio_stdio_orig = orig;
- atexit(ttyclose);
- }
- raw_stdio = 1;
-}
-
-static int
-ttyread(struct ttyfd *tf)
-{
- unsigned char rb;
-
- if (read(tf->rfd, &rb, 1) == 1)
- return (rb);
- else
- return (-1);
-}
-
-static void
-ttywrite(struct ttyfd *tf, unsigned char wb)
-{
-
- (void)write(tf->wfd, &wb, 1);
-}
-
-static void
-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.rfd, 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
-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
-rxfifo_getchar(struct uart_softc *sc)
-{
- 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
-rxfifo_numchars(struct uart_softc *sc)
-{
- struct fifo *fifo = &sc->rxfifo;
-
- return (fifo->num);
-}
-
-static void
-uart_opentty(struct uart_softc *sc)
-{
-
- ttyopen(&sc->tty);
- sc->mev = mevent_add(sc->tty.rfd, EVF_READ, uart_drain, sc);
- assert(sc->mev != NULL);
-}
-
static uint8_t
modem_status(uint8_t mcr)
{
@@ -326,12 +144,13 @@ modem_status(uint8_t mcr)
* Return an interrupt reason if one is available.
*/
static int
-uart_intr_reason(struct uart_softc *sc)
+uart_intr_reason(struct uart_ns16550_softc *sc)
{
if ((sc->lsr & LSR_OE) != 0 && (sc->ier & IER_ERLS) != 0)
return (IIR_RLS);
- else if (rxfifo_numchars(sc) > 0 && (sc->ier & IER_ERXRDY) != 0)
+ else if (uart_rxfifo_numchars(sc->backend) > 0 &&
+ (sc->ier & IER_ERXRDY) != 0)
return (IIR_RXTOUT);
else if (sc->thre_int_pending && (sc->ier & IER_ETXRDY) != 0)
return (IIR_TXRDY);
@@ -342,7 +161,7 @@ uart_intr_reason(struct uart_softc *sc)
}
static void
-uart_reset(struct uart_softc *sc)
+uart_reset(struct uart_ns16550_softc *sc)
{
uint16_t divisor;
@@ -351,7 +170,7 @@ uart_reset(struct uart_softc *sc)
sc->dlh = divisor >> 16;
sc->msr = modem_status(sc->mcr);
- rxfifo_reset(sc, 1); /* no fifo until enabled by software */
+ uart_rxfifo_reset(sc->backend, 1);
}
/*
@@ -359,7 +178,7 @@ uart_reset(struct uart_softc *sc)
* interrupt condition to report to the processor.
*/
static void
-uart_toggle_intr(struct uart_softc *sc)
+uart_toggle_intr(struct uart_ns16550_softc *sc)
{
uint8_t intr_reason;
@@ -372,14 +191,13 @@ uart_toggle_intr(struct uart_softc *sc)
}
static void
-uart_drain(int fd, enum ev_type ev, void *arg)
+uart_drain(int fd __unused, enum ev_type ev, void *arg)
{
- struct uart_softc *sc;
- int ch;
+ struct uart_ns16550_softc *sc;
+ bool loopback;
sc = arg;
- assert(fd == sc->tty.rfd);
assert(ev == EVF_READ);
/*
@@ -389,21 +207,16 @@ uart_drain(int fd, enum ev_type ev, void *arg)
*/
pthread_mutex_lock(&sc->mtx);
- if ((sc->mcr & MCR_LOOPBACK) != 0) {
- (void) ttyread(&sc->tty);
- } else {
- while (rxfifo_available(sc) &&
- ((ch = ttyread(&sc->tty)) != -1)) {
- rxfifo_putchar(sc, ch);
- }
+ loopback = (sc->mcr & MCR_LOOPBACK) != 0;
+ uart_rxfifo_drain(sc->backend, loopback);
+ if (!loopback)
uart_toggle_intr(sc);
- }
pthread_mutex_unlock(&sc->mtx);
}
void
-uart_write(struct uart_softc *sc, int offset, uint8_t value)
+uart_ns16550_write(struct uart_ns16550_softc *sc, int offset, uint8_t value)
{
int fifosz;
uint8_t msr;
@@ -427,12 +240,9 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value)
switch (offset) {
case REG_DATA:
- if (sc->mcr & MCR_LOOPBACK) {
- if (rxfifo_putchar(sc, value) != 0)
- sc->lsr |= LSR_OE;
- } else if (sc->tty.opened) {
- ttywrite(&sc->tty, value);
- } /* else drop on floor */
+ if (uart_rxfifo_putchar(sc->backend, value,
+ (sc->mcr & MCR_LOOPBACK) != 0))
+ sc->lsr |= LSR_OE;
sc->thre_int_pending = true;
break;
case REG_IER:
@@ -451,8 +261,9 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value)
* the FIFO contents are reset.
*/
if ((sc->fcr & FCR_ENABLE) ^ (value & FCR_ENABLE)) {
- fifosz = (value & FCR_ENABLE) ? FIFOSZ : 1;
- rxfifo_reset(sc, fifosz);
+ fifosz = (value & FCR_ENABLE) ?
+ uart_rxfifo_size(sc->backend) : 1;
+ uart_rxfifo_reset(sc->backend, fifosz);
}
/*
@@ -463,7 +274,8 @@ uart_write(struct uart_softc *sc, int offset, uint8_t value)
sc->fcr = 0;
} else {
if ((value & FCR_RCV_RST) != 0)
- rxfifo_reset(sc, FIFOSZ);
+ uart_rxfifo_reset(sc->backend,
+ uart_rxfifo_size(sc->backend));
sc->fcr = value &
(FCR_ENABLE | FCR_DMA | FCR_RX_MASK);
@@ -522,7 +334,7 @@ done:
}
uint8_t
-uart_read(struct uart_softc *sc, int offset)
*** 193 LINES SKIPPED ***