sys/powerpc/powernv/opal_dbg.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (C) 2019 Leandro Lupori
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  18  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  19  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  20  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  21  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  22  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  23  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  24  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 #include <sys/cdefs.h>
  28 __FBSDID("$FreeBSD$");
  29
  30 #include <sys/linker_set.h>
  31 #include <sys/param.h>
  32 #include <sys/types.h>
  33
  34 struct thread;
  35
  36 #include <vm/vm.h>
  37 #include <vm/pmap.h>
  38
  39 #include <dev/ofw/openfirm.h>
  40 #include <gdb/gdb.h>
  41
  42 #include "opal.h"
  43
  44 static gdb_probe_f uart_opal_dbg_probe;
  45 static gdb_init_f uart_opal_dbg_init;
  46 static gdb_term_f uart_opal_dbg_term;
  47 static gdb_getc_f uart_opal_dbg_getc;
  48 static gdb_putc_f uart_opal_dbg_putc;
  49
  50 GDB_DBGPORT(uart_opal, uart_opal_dbg_probe,
  51     uart_opal_dbg_init, uart_opal_dbg_term,
  52     uart_opal_dbg_getc, uart_opal_dbg_putc);
  53
  54 static int64_t termnum;
  55
  56 static int
  57 uart_opal_dbg_probe(void)
  58 {
  59         char buf[64];
  60         cell_t reg;
  61         phandle_t dev;
  62
  63         if (!getenv_string("hw.uart.dbgport", buf, sizeof(buf)))
  64                 return (-1);
  65         if ((dev = OF_finddevice(buf)) == -1)
  66                 return (-1);
  67
  68         if (OF_getprop(dev, "device_type", buf, sizeof(buf)) == -1)
  69                 return (-1);
  70         if (strcmp(buf, "serial") != 0)
  71                 return (-1);
  72
  73         if (OF_getprop(dev, "compatible", buf, sizeof(buf)) == -1)
  74                 return (-1);
  75         if (strcmp(buf, "ibm,opal-console-raw") != 0)
  76                 return (-1);
  77
  78         reg = ~0U;
  79         OF_getencprop(dev, "reg", &reg, sizeof(reg));
  80         if (reg == ~0U)
  81                 return (-1);
  82         termnum = reg;
  83
  84         return (0);
  85 }
  86
  87 static void
  88 uart_opal_dbg_init(void)
  89 {
  90 }
  91
  92 static void
  93 uart_opal_dbg_term(void)
  94 {
  95 }
  96
  97 static int
  98 uart_opal_dbg_getc(void)
  99 {
 100         char c;
 101         int err;
 102         int64_t len;
 103         uint64_t lenp, bufp;
 104
 105         len = 1;
 106         if (pmap_bootstrapped) {
 107                 lenp = vtophys(&len);
 108                 bufp = vtophys(&c);
 109         } else {
 110                 lenp = (uint64_t)&len;
 111                 bufp = (uint64_t)&c;
 112         }
 113
 114         err = opal_call(OPAL_CONSOLE_READ, termnum, lenp, bufp);
 115         if (err != OPAL_SUCCESS || len != 1)
 116                 return (-1);
 117
 118         opal_call(OPAL_POLL_EVENTS, NULL);
 119
 120         return (c);
 121 }
 122
 123 static void
 124 uart_opal_dbg_putc(int c)
 125 {
 126         char ch;
 127         int err;
 128         int64_t len;
 129         uint64_t lenp, bufp;
 130
 131         ch = (unsigned char)c;
 132         len = 1;
 133         if (pmap_bootstrapped) {
 134                 lenp = vtophys(&len);
 135                 bufp = vtophys(&ch);
 136         } else {
 137                 lenp = (uint64_t)&len;
 138                 bufp = (uint64_t)&ch;
 139         }
 140
 141         for (;;) {
 142                 err = opal_call(OPAL_CONSOLE_WRITE, termnum, lenp, bufp);
 143                 /* Clear FIFO if needed. */
 144                 if (err == OPAL_BUSY_EVENT)
 145                         opal_call(OPAL_POLL_EVENTS, NULL);
 146                 else
 147                         /* break on success or unrecoverable errors */
 148                         break;
 149         }
 150         DELAY(100);
 151 }