Merge tag 'nios2-v3.20-rc1' of git://git.rocketboards.org/linux-socfpga-next

Pull arch/nios2 update from Ley Foon Tan:
 "Here is the nios2 update for 3.20:

   - add early printk support
   - add kgdb support
   - add compressed kernel support
   - bugfixes"

* tag 'nios2-v3.20-rc1' of git://git.rocketboards.org/linux-socfpga-next:
  nios2: add kgdb support
  MAINTAINERS: update arch/nios2 git tree
  nios2: default CONFIG_NIOS2_BOOT_LINK_OFFSET to 8MB
  nios2: Add support for compressed kernel
  nios2: add early printk support
  nios2: Port OOM changes to do_page_fault()
  nios2: Remove unused prepare_to_copy()

1 files changed, 171 insertions, 0 deletions

diff --git a/arch/nios2/kernel/kgdb.c b/arch/nios2/kernel/kgdb.c
new file mode 100644
index 000000000000..117859122d1c
--- /dev/null
+++ b/arch/nios2/kernel/kgdb.c
@@ -0,0 +1,171 @@
+/*
+ * Nios2 KGDB support
+ *
+ * Copyright (C) 2015 Altera Corporation
+ * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
+ *
+ * Based on the code posted by Kazuyasu on the Altera Forum at:
+ * http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+#include <linux/ptrace.h>
+#include <linux/kgdb.h>
+#include <linux/kdebug.h>
+#include <linux/io.h>
+
+static int wait_for_remote_debugger;
+
+struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
+{
+	{ "zero", GDB_SIZEOF_REG, -1 },
+	{ "at", GDB_SIZEOF_REG, offsetof(struct pt_regs, r1) },
+	{ "r2", GDB_SIZEOF_REG, offsetof(struct pt_regs, r2) },
+	{ "r3", GDB_SIZEOF_REG, offsetof(struct pt_regs, r3) },
+	{ "r4", GDB_SIZEOF_REG, offsetof(struct pt_regs, r4) },
+	{ "r5", GDB_SIZEOF_REG, offsetof(struct pt_regs, r5) },
+	{ "r6", GDB_SIZEOF_REG, offsetof(struct pt_regs, r6) },
+	{ "r7", GDB_SIZEOF_REG, offsetof(struct pt_regs, r7) },
+	{ "r8", GDB_SIZEOF_REG, offsetof(struct pt_regs, r8) },
+	{ "r9", GDB_SIZEOF_REG, offsetof(struct pt_regs, r9) },
+	{ "r10", GDB_SIZEOF_REG, offsetof(struct pt_regs, r10) },
+	{ "r11", GDB_SIZEOF_REG, offsetof(struct pt_regs, r11) },
+	{ "r12", GDB_SIZEOF_REG, offsetof(struct pt_regs, r12) },
+	{ "r13", GDB_SIZEOF_REG, offsetof(struct pt_regs, r13) },
+	{ "r14", GDB_SIZEOF_REG, offsetof(struct pt_regs, r14) },
+	{ "r15", GDB_SIZEOF_REG, offsetof(struct pt_regs, r15) },
+	{ "r16", GDB_SIZEOF_REG, -1 },
+	{ "r17", GDB_SIZEOF_REG, -1 },
+	{ "r18", GDB_SIZEOF_REG, -1 },
+	{ "r19", GDB_SIZEOF_REG, -1 },
+	{ "r20", GDB_SIZEOF_REG, -1 },
+	{ "r21", GDB_SIZEOF_REG, -1 },
+	{ "r22", GDB_SIZEOF_REG, -1 },
+	{ "r23", GDB_SIZEOF_REG, -1 },
+	{ "et", GDB_SIZEOF_REG, -1 },
+	{ "bt", GDB_SIZEOF_REG, -1 },
+	{ "gp", GDB_SIZEOF_REG, offsetof(struct pt_regs, gp) },
+	{ "sp", GDB_SIZEOF_REG, offsetof(struct pt_regs, sp) },
+	{ "fp", GDB_SIZEOF_REG, offsetof(struct pt_regs, fp) },
+	{ "ea", GDB_SIZEOF_REG, -1 },
+	{ "ba", GDB_SIZEOF_REG, -1 },
+	{ "ra", GDB_SIZEOF_REG, offsetof(struct pt_regs, ra) },
+	{ "pc", GDB_SIZEOF_REG, offsetof(struct pt_regs, ea) },
+	{ "status", GDB_SIZEOF_REG, -1 },
+	{ "estatus", GDB_SIZEOF_REG, offsetof(struct pt_regs, estatus) },
+	{ "bstatus", GDB_SIZEOF_REG, -1 },
+	{ "ienable", GDB_SIZEOF_REG, -1 },
+	{ "ipending", GDB_SIZEOF_REG, -1},
+	{ "cpuid", GDB_SIZEOF_REG, -1 },
+	{ "ctl6", GDB_SIZEOF_REG, -1 },
+	{ "exception", GDB_SIZEOF_REG, -1 },
+	{ "pteaddr", GDB_SIZEOF_REG, -1 },
+	{ "tlbacc", GDB_SIZEOF_REG, -1 },
+	{ "tlbmisc", GDB_SIZEOF_REG, -1 },
+	{ "eccinj", GDB_SIZEOF_REG, -1 },
+	{ "badaddr", GDB_SIZEOF_REG, -1 },
+	{ "config", GDB_SIZEOF_REG, -1 },
+	{ "mpubase", GDB_SIZEOF_REG, -1 },
+	{ "mpuacc", GDB_SIZEOF_REG, -1 },
+};
+
+char *dbg_get_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return NULL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy(mem, (void *)regs + dbg_reg_def[regno].offset,
+		       dbg_reg_def[regno].size);
+	else
+		memset(mem, 0, dbg_reg_def[regno].size);
+
+	return dbg_reg_def[regno].name;
+}
+
+int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)
+{
+	if (regno >= DBG_MAX_REG_NUM || regno < 0)
+		return -EINVAL;
+
+	if (dbg_reg_def[regno].offset != -1)
+		memcpy((void *)regs + dbg_reg_def[regno].offset, mem,
+		       dbg_reg_def[regno].size);
+
+	return 0;
+}
+
+void sleeping_thread_to_gdb_regs(unsigned long *gdb_regs, struct task_struct *p)
+{
+	memset((char *)gdb_regs, 0, NUMREGBYTES);
+	gdb_regs[GDB_SP] = p->thread.kregs->sp;
+	gdb_regs[GDB_PC] = p->thread.kregs->ea;
+}
+
+void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc)
+{
+	regs->ea = pc;
+}
+
+int kgdb_arch_handle_exception(int vector, int signo, int err_code,
+				char *remcom_in_buffer, char *remcom_out_buffer,
+				struct pt_regs *regs)
+{
+	char *ptr;
+	unsigned long addr;
+
+	switch (remcom_in_buffer[0]) {
+	case 's':
+	case 'c':
+		/* handle the optional parameters */
+		ptr = &remcom_in_buffer[1];
+		if (kgdb_hex2long(&ptr, &addr))
+			regs->ea = addr;
+
+		return 0;
+	}
+
+	return -1; /* this means that we do not want to exit from the handler */
+}
+
+asmlinkage void kgdb_breakpoint_c(struct pt_regs *regs)
+{
+	/*
+	 * The breakpoint entry code has moved the PC on by 4 bytes, so we must
+	 * move it back.  This could be done on the host but we do it here
+	 */
+	if (!wait_for_remote_debugger)
+		regs->ea -= 4;
+	else	/* pass the first trap 30 code */
+		wait_for_remote_debugger = 0;
+
+	kgdb_handle_exception(30, SIGTRAP, 0, regs);
+}
+
+int kgdb_arch_init(void)
+{
+	wait_for_remote_debugger = 1;
+	return 0;
+}
+
+void kgdb_arch_exit(void)
+{
+	/* Nothing to do */
+}
+
+struct kgdb_arch arch_kgdb_ops = {
+	/* Breakpoint instruction: trap 30 */
+	.gdb_bpt_instr = { 0xba, 0x6f, 0x3b, 0x00 },
+};