diff options
Diffstat (limited to 'sys/dev/uart/uart_subr.c')
| -rw-r--r-- | sys/dev/uart/uart_subr.c | 247 |
1 files changed, 247 insertions, 0 deletions
diff --git a/sys/dev/uart/uart_subr.c b/sys/dev/uart/uart_subr.c new file mode 100644 index 0000000..9a3cb85 --- /dev/null +++ b/sys/dev/uart/uart_subr.c @@ -0,0 +1,247 @@ +/* + * Copyright (c) 2004 Marcel Moolenaar + * 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 ``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 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/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/bus.h> + +#include <machine/bus.h> +#include <machine/vmparam.h> + +#include <dev/uart/uart.h> +#include <dev/uart/uart_cpu.h> + +#define UART_TAG_BR 0 +#define UART_TAG_CH 1 +#define UART_TAG_DB 2 +#define UART_TAG_DT 3 +#define UART_TAG_IO 4 +#define UART_TAG_MM 5 +#define UART_TAG_PA 6 +#define UART_TAG_RS 7 +#define UART_TAG_SB 8 +#define UART_TAG_XO 9 + +static bus_addr_t +uart_parse_addr(__const char **p) +{ + return (strtoul(*p, (char**)(uintptr_t)p, 0)); +} + +static long +uart_parse_long(__const char **p) +{ + return (strtol(*p, (char**)(uintptr_t)p, 0)); +} + +static int +uart_parse_parity(__const char **p) +{ + if (!strncmp(*p, "even", 4)) { + *p += 4; + return UART_PARITY_EVEN; + } + if (!strncmp(*p, "mark", 4)) { + *p += 4; + return UART_PARITY_MARK; + } + if (!strncmp(*p, "none", 4)) { + *p += 4; + return UART_PARITY_NONE; + } + if (!strncmp(*p, "odd", 3)) { + *p += 3; + return UART_PARITY_ODD; + } + if (!strncmp(*p, "space", 5)) { + *p += 5; + return UART_PARITY_SPACE; + } + return (-1); +} + +static int +uart_parse_tag(__const char **p) +{ + int tag; + + if ((*p)[0] == 'b' && (*p)[1] == 'r') { + tag = UART_TAG_BR; + goto out; + } + if ((*p)[0] == 'c' && (*p)[1] == 'h') { + tag = UART_TAG_CH; + goto out; + } + if ((*p)[0] == 'd' && (*p)[1] == 'b') { + tag = UART_TAG_DB; + goto out; + } + if ((*p)[0] == 'd' && (*p)[1] == 't') { + tag = UART_TAG_DT; + goto out; + } + if ((*p)[0] == 'i' && (*p)[1] == 'o') { + tag = UART_TAG_IO; + goto out; + } + if ((*p)[0] == 'm' && (*p)[1] == 'm') { + tag = UART_TAG_MM; + goto out; + } + if ((*p)[0] == 'p' && (*p)[1] == 'a') { + tag = UART_TAG_PA; + goto out; + } + if ((*p)[0] == 'r' && (*p)[1] == 's') { + tag = UART_TAG_RS; + goto out; + } + if ((*p)[0] == 's' && (*p)[1] == 'b') { + tag = UART_TAG_SB; + goto out; + } + if ((*p)[0] == 'x' && (*p)[1] == 'o') { + tag = UART_TAG_XO; + goto out; + } + return (-1); + +out: + *p += 2; + if ((*p)[0] != ':') + return (-1); + (*p)++; + return (tag); +} + +/* + * Parse a device specification. The specification is a list of attributes + * seperated by commas. Each attribute is a tag-value pair with the tag and + * value seperated by a colon. Supported tags are: + * + * br = Baudrate + * ch = Channel + * db = Data bits + * dt = Device type + * io = I/O port address + * mm = Memory mapped I/O address + * pa = Parity + * rs = Register shift + * sb = Stopbits + * xo = Device clock (xtal oscillator) + * + * The io and mm tags are mutually exclusive. + */ + +int +uart_getenv(int devtype, struct uart_devinfo *di) +{ + __const char *spec; + bus_addr_t addr = ~0U; + + /* + * Check the environment variables "hw.uart.console" and + * "hw.uart.dbgport". These variables, when present, specify + * which UART port is to be used as serial console or debug + * port (resp). + */ + if (devtype == UART_DEV_CONSOLE) + spec = getenv("hw.uart.console"); + else if (devtype == UART_DEV_DBGPORT) + spec = getenv("hw.uart.dbgport"); + else + return (ENXIO); + + /* Set defaults. */ + di->ops = uart_ns8250_ops; + di->bas.chan = 0; + di->bas.regshft = 0; + di->bas.rclk = 0; + di->baudrate = 0; + di->databits = 8; + di->stopbits = 1; + di->parity = UART_PARITY_NONE; + + /* Parse the attributes. */ + while (1) { + switch (uart_parse_tag(&spec)) { + case UART_TAG_BR: + di->baudrate = uart_parse_long(&spec); + break; + case UART_TAG_CH: + di->bas.chan = uart_parse_long(&spec); + break; + case UART_TAG_DB: + di->databits = uart_parse_long(&spec); + break; + case UART_TAG_DT: + return (EINVAL); /* XXX not yet implemented. */ + break; + case UART_TAG_IO: + di->bas.bst = uart_bus_space_io; + addr = uart_parse_addr(&spec); + break; + case UART_TAG_MM: + di->bas.bst = uart_bus_space_mem; + addr = uart_parse_addr(&spec); + break; + case UART_TAG_PA: + di->parity = uart_parse_parity(&spec); + break; + case UART_TAG_RS: + di->bas.regshft = uart_parse_long(&spec); + break; + case UART_TAG_SB: + di->stopbits = uart_parse_long(&spec); + break; + case UART_TAG_XO: + di->bas.rclk = uart_parse_long(&spec); + break; + default: + return (EINVAL); + } + if (*spec == '\0') + break; + if (*spec != ',') + return (EINVAL); + spec++; + } + + /* + * If we still have an invalid address, the specification must be + * missing an I/O port or memory address. We don't like that. + */ + if (addr == ~0U) + return (EINVAL); + /* XXX the size of the mapping depends on the UART class. */ + if (bus_space_map(di->bas.bst, addr, 8, 0, &di->bas.bsh) != 0) + return (EINVAL); + return (0); +} |
