freebsd-dev/sys/dev/uart/uart_subr.c
Pedro F. Giffuni 718cf2ccb9 sys/dev: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 14:52:40 +00:00

323 lines
7.2 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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 struct uart_class *uart_classes[] = {
&uart_ns8250_class,
&uart_sab82532_class,
&uart_z8530_class,
#if defined(__arm__)
&uart_s3c2410_class,
#endif
};
static bus_addr_t
uart_parse_addr(const char **p)
{
return (strtoul(*p, (char**)(uintptr_t)p, 0));
}
static struct uart_class *
uart_parse_class(struct uart_class *class, const char **p)
{
struct uart_class *uc;
const char *nm;
size_t len;
u_int i;
for (i = 0; i < nitems(uart_classes); i++) {
uc = uart_classes[i];
nm = uart_getname(uc);
if (nm == NULL || *nm == '\0')
continue;
len = strlen(nm);
if (strncmp(nm, *p, len) == 0) {
*p += len;
return (uc);
}
}
return (class);
}
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
* separated by commas. Each attribute is a tag-value pair with the tag and
* value separated 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, struct uart_class *class)
{
const char *spec;
char *cp;
bus_addr_t addr = ~0U;
int error;
/*
* All uart_class references are weak. Make sure the default
* device class has been compiled-in.
*/
if (class == NULL)
return (ENXIO);
/*
* 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).
*/
switch (devtype) {
case UART_DEV_CONSOLE:
cp = kern_getenv("hw.uart.console");
break;
case UART_DEV_DBGPORT:
cp = kern_getenv("hw.uart.dbgport");
break;
default:
cp = NULL;
break;
}
if (cp == NULL)
return (ENXIO);
/* Set defaults. */
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. */
spec = cp;
for (;;) {
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:
class = uart_parse_class(class, &spec);
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:
freeenv(cp);
return (EINVAL);
}
if (*spec == '\0')
break;
if (*spec != ',') {
freeenv(cp);
return (EINVAL);
}
spec++;
}
freeenv(cp);
/*
* 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);
/*
* Accept only the well-known baudrates. Any invalid baudrate
* is silently replaced with a 0-valued baudrate. The 0 baudrate
* has special meaning. It means that we're not supposed to
* program the baudrate and simply communicate with whatever
* speed the hardware is currently programmed for.
*/
if (di->baudrate >= 19200) {
if (di->baudrate % 19200)
di->baudrate = 0;
} else if (di->baudrate >= 1200) {
if (di->baudrate % 1200)
di->baudrate = 0;
} else if (di->baudrate > 0) {
if (di->baudrate % 75)
di->baudrate = 0;
} else
di->baudrate = 0;
/* Set the ops and create a bus space handle. */
di->ops = uart_getops(class);
error = bus_space_map(di->bas.bst, addr, uart_getrange(class), 0,
&di->bas.bsh);
return (error);
}