Add initial support for kgdb(1) on PowerPC.

2 files changed, 186 insertions, 5 deletions

diff --git a/gnu/usr.bin/gdb/Makefile b/gnu/usr.bin/gdb/Makefile
index 8eabacb..74a3598 100644
--- a/gnu/usr.bin/gdb/Makefile
+++ b/gnu/usr.bin/gdb/Makefile
@@ -1,9 +1,5 @@
 # $FreeBSD$
 
-SUBDIR=	doc libgdb gdb gdbtui
-
-.if ${MACHINE_ARCH} != "powerpc"
-SUBDIR+= kgdb
-.endif
+SUBDIR=	doc libgdb gdb gdbtui kgdb
 
 .include <bsd.subdir.mk>
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_powerpc.c b/gnu/usr.bin/gdb/kgdb/trgt_powerpc.c
new file mode 100644
index 0000000..8ca07b4
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_powerpc.c
@@ -0,0 +1,185 @@
+/*-
+ * Copyright (c) 2006 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/types.h>
+#include <machine/pcb.h>
+#include <machine/frame.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+#include <frame-unwind.h>
+#include <ppc-tdep.h>
+
+#include "kgdb.h"
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;	
+	struct gdbarch_tdep *tdep;
+	int i;
+
+	tdep = gdbarch_tdep (current_gdbarch);
+
+	kt = kgdb_thr_lookup_tid(ptid_get_tid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+
+	/*
+	 * r14-r31 are saved in the pcb
+	 */
+	for (i = 14; i <= 31; i++) {
+		supply_register(tdep->ppc_gp0_regnum + i,
+		    (char *)&pcb.pcb_context[i]);
+	}
+	
+	/* r1 is saved in the sp field */
+	supply_register(tdep->ppc_gp0_regnum + 1, (char *)&pcb.pcb_sp);
+
+	supply_register(tdep->ppc_lr_regnum, (char *)&pcb.pcb_lr);
+	supply_register(tdep->ppc_cr_regnum, (char *)&pcb.pcb_cr);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}
+
+struct kgdb_frame_cache {
+	CORE_ADDR	pc;
+	CORE_ADDR	sp;
+};
+
+static struct kgdb_frame_cache *
+kgdb_trgt_frame_cache(struct frame_info *next_frame, void **this_cache)
+{
+	char buf[MAX_REGISTER_SIZE];
+	struct kgdb_frame_cache *cache;
+
+	cache = *this_cache;
+	if (cache == NULL) {
+		cache = FRAME_OBSTACK_ZALLOC(struct kgdb_frame_cache);
+		*this_cache = cache;
+		cache->pc = frame_func_unwind(next_frame);
+		frame_unwind_register(next_frame, SP_REGNUM, buf);
+		cache->sp = extract_unsigned_integer(buf,
+		    register_size(current_gdbarch, SP_REGNUM));
+	}
+	return (cache);
+}
+
+static void
+kgdb_trgt_trapframe_this_id(struct frame_info *next_frame, void **this_cache,
+    struct frame_id *this_id)
+{
+	struct kgdb_frame_cache *cache;
+
+	cache = kgdb_trgt_frame_cache(next_frame, this_cache);
+	*this_id = frame_id_build(cache->sp, cache->pc);
+}
+
+static void
+kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
+    void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
+    CORE_ADDR *addrp, int *realnump, void *valuep)
+{
+	char dummy_valuep[MAX_REGISTER_SIZE];
+	struct gdbarch_tdep *tdep;
+	struct kgdb_frame_cache *cache;
+	int ofs, regsz;
+
+	tdep = gdbarch_tdep(current_gdbarch);
+	regsz = register_size(current_gdbarch, regnum);
+
+	if (valuep == NULL)
+		valuep = dummy_valuep;
+	memset(valuep, 0, regsz);
+	*optimizedp = 0;
+	*addrp = 0;
+	*lvalp = not_lval;
+	*realnump = -1;
+
+	if (regnum >= tdep->ppc_gp0_regnum &&
+	    regnum <= tdep->ppc_gplast_regnum)
+		ofs = offsetof(struct trapframe,
+		    fixreg[regnum - tdep->ppc_gp0_regnum]);
+	else if (regnum == tdep->ppc_lr_regnum)
+		ofs = offsetof(struct trapframe, lr);
+	else if (regnum == tdep->ppc_cr_regnum)
+		ofs = offsetof(struct trapframe, cr);
+	else if (regnum == tdep->ppc_xer_regnum)
+		ofs = offsetof(struct trapframe, xer);
+	else if (regnum == tdep->ppc_ctr_regnum)
+		ofs = offsetof(struct trapframe, ctr);
+	else if (regnum == PC_REGNUM)
+		ofs = offsetof(struct trapframe, srr0);
+	else
+		return;
+
+	cache = kgdb_trgt_frame_cache(next_frame, this_cache);
+	*addrp = cache->sp + 8 + ofs;
+	*lvalp = lval_memory;
+	target_read_memory(*addrp, valuep, regsz);
+}
+
+static const struct frame_unwind kgdb_trgt_trapframe_unwind = {
+        UNKNOWN_FRAME,
+        &kgdb_trgt_trapframe_this_id,
+        &kgdb_trgt_trapframe_prev_register
+};
+
+const struct frame_unwind *
+kgdb_trgt_trapframe_sniffer(struct frame_info *next_frame)
+{
+	char *pname;
+	CORE_ADDR pc;
+
+	pc = frame_pc_unwind(next_frame);
+	pname = NULL;
+	find_pc_partial_function(pc, &pname, NULL, NULL);
+	if (pname == NULL)
+		return (NULL);
+	if (strcmp(pname, "asttrapexit") == 0 ||
+	    strcmp(pname, "trapexit") == 0)
+		return (&kgdb_trgt_trapframe_unwind);
+	/* printf("%s: %llx =%s\n", __func__, pc, pname); */
+	return (NULL);
+}