freebsd-skq/sys/powerpc/powernv/opal_dbg.c
Leandro Lupori a16111e6a2 [PPC64] Enable opal console use as a GDB DBGPORT
This change makes it possible to use OPAL console as a GDB debug port.

Similar to uart and uart_phyp debug ports, it has to be enabled by
setting the hw.uart.dbgport variable to the serial console node
of the device tree.

Reviewed by:	jhibbits
Differential Revision:	https://reviews.freebsd.org/D22649
2019-12-09 13:09:32 +00:00

152 lines
3.5 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 2019 Leandro Lupori
*
* 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 TOOLS GMBH 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/linker_set.h>
#include <sys/param.h>
#include <sys/types.h>
struct thread;
#include <vm/vm.h>
#include <vm/pmap.h>
#include <dev/ofw/openfirm.h>
#include <gdb/gdb.h>
#include "opal.h"
static gdb_probe_f uart_opal_dbg_probe;
static gdb_init_f uart_opal_dbg_init;
static gdb_term_f uart_opal_dbg_term;
static gdb_getc_f uart_opal_dbg_getc;
static gdb_putc_f uart_opal_dbg_putc;
GDB_DBGPORT(uart_opal, uart_opal_dbg_probe,
uart_opal_dbg_init, uart_opal_dbg_term,
uart_opal_dbg_getc, uart_opal_dbg_putc);
static int64_t termnum;
static int
uart_opal_dbg_probe(void)
{
char buf[64];
cell_t reg;
phandle_t dev;
if (!getenv_string("hw.uart.dbgport", buf, sizeof(buf)))
return (-1);
if ((dev = OF_finddevice(buf)) == -1)
return (-1);
if (OF_getprop(dev, "device_type", buf, sizeof(buf)) == -1)
return (-1);
if (strcmp(buf, "serial") != 0)
return (-1);
if (OF_getprop(dev, "compatible", buf, sizeof(buf)) == -1)
return (-1);
if (strcmp(buf, "ibm,opal-console-raw") != 0)
return (-1);
reg = ~0U;
OF_getencprop(dev, "reg", &reg, sizeof(reg));
if (reg == ~0U)
return (-1);
termnum = reg;
return (0);
}
static void
uart_opal_dbg_init(void)
{
}
static void
uart_opal_dbg_term(void)
{
}
static int
uart_opal_dbg_getc(void)
{
char c;
int err;
int64_t len;
uint64_t lenp, bufp;
len = 1;
if (pmap_bootstrapped) {
lenp = vtophys(&len);
bufp = vtophys(&c);
} else {
lenp = (uint64_t)&len;
bufp = (uint64_t)&c;
}
err = opal_call(OPAL_CONSOLE_READ, termnum, lenp, bufp);
if (err != OPAL_SUCCESS || len != 1)
return (-1);
opal_call(OPAL_POLL_EVENTS, NULL);
return (c);
}
static void
uart_opal_dbg_putc(int c)
{
char ch;
int err;
int64_t len;
uint64_t lenp, bufp;
ch = (unsigned char)c;
len = 1;
if (pmap_bootstrapped) {
lenp = vtophys(&len);
bufp = vtophys(&ch);
} else {
lenp = (uint64_t)&len;
bufp = (uint64_t)&ch;
}
for (;;) {
err = opal_call(OPAL_CONSOLE_WRITE, termnum, lenp, bufp);
/* Clear FIFO if needed. */
if (err == OPAL_BUSY_EVENT)
opal_call(OPAL_POLL_EVENTS, NULL);
else
/* break on success or unrecoverable errors */
break;
}
DELAY(100);
}