1627 lines
49 KiB
C
1627 lines
49 KiB
C
/*
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* arch/cris/arch-v32/kernel/kgdb.c
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*
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* CRIS v32 version by Orjan Friberg, Axis Communications AB.
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*
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* S390 version
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* Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
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* Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
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*
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* Originally written by Glenn Engel, Lake Stevens Instrument Division
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*
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* Contributed by HP Systems
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*
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* Modified for SPARC by Stu Grossman, Cygnus Support.
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*
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* Modified for Linux/MIPS (and MIPS in general) by Andreas Busse
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* Send complaints, suggestions etc. to <andy@waldorf-gmbh.de>
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*
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* Copyright (C) 1995 Andreas Busse
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*/
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/* FIXME: Check the documentation. */
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/*
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* kgdb usage notes:
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* -----------------
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*
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* If you select CONFIG_ETRAX_KGDB in the configuration, the kernel will be
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* built with different gcc flags: "-g" is added to get debug infos, and
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* "-fomit-frame-pointer" is omitted to make debugging easier. Since the
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* resulting kernel will be quite big (approx. > 7 MB), it will be stripped
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* before compresion. Such a kernel will behave just as usually, except if
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* given a "debug=<device>" command line option. (Only serial devices are
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* allowed for <device>, i.e. no printers or the like; possible values are
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* machine depedend and are the same as for the usual debug device, the one
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* for logging kernel messages.) If that option is given and the device can be
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* initialized, the kernel will connect to the remote gdb in trap_init(). The
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* serial parameters are fixed to 8N1 and 115200 bps, for easyness of
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* implementation.
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*
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* To start a debugging session, start that gdb with the debugging kernel
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* image (the one with the symbols, vmlinux.debug) named on the command line.
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* This file will be used by gdb to get symbol and debugging infos about the
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* kernel. Next, select remote debug mode by
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* target remote <device>
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* where <device> is the name of the serial device over which the debugged
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* machine is connected. Maybe you have to adjust the baud rate by
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* set remotebaud <rate>
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* or also other parameters with stty:
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* shell stty ... </dev/...
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* If the kernel to debug has already booted, it waited for gdb and now
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* connects, and you'll see a breakpoint being reported. If the kernel isn't
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* running yet, start it now. The order of gdb and the kernel doesn't matter.
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* Another thing worth knowing about in the getting-started phase is how to
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* debug the remote protocol itself. This is activated with
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* set remotedebug 1
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* gdb will then print out each packet sent or received. You'll also get some
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* messages about the gdb stub on the console of the debugged machine.
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*
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* If all that works, you can use lots of the usual debugging techniques on
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* the kernel, e.g. inspecting and changing variables/memory, setting
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* breakpoints, single stepping and so on. It's also possible to interrupt the
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* debugged kernel by pressing C-c in gdb. Have fun! :-)
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*
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* The gdb stub is entered (and thus the remote gdb gets control) in the
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* following situations:
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*
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* - If breakpoint() is called. This is just after kgdb initialization, or if
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* a breakpoint() call has been put somewhere into the kernel source.
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* (Breakpoints can of course also be set the usual way in gdb.)
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* In eLinux, we call breakpoint() in init/main.c after IRQ initialization.
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*
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* - If there is a kernel exception, i.e. bad_super_trap() or die_if_kernel()
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* are entered. All the CPU exceptions are mapped to (more or less..., see
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* the hard_trap_info array below) appropriate signal, which are reported
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* to gdb. die_if_kernel() is usually called after some kind of access
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* error and thus is reported as SIGSEGV.
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*
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* - When panic() is called. This is reported as SIGABRT.
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*
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* - If C-c is received over the serial line, which is treated as
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* SIGINT.
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*
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* Of course, all these signals are just faked for gdb, since there is no
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* signal concept as such for the kernel. It also isn't possible --obviously--
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* to set signal handlers from inside gdb, or restart the kernel with a
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* signal.
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*
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* Current limitations:
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*
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* - While the kernel is stopped, interrupts are disabled for safety reasons
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* (i.e., variables not changing magically or the like). But this also
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* means that the clock isn't running anymore, and that interrupts from the
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* hardware may get lost/not be served in time. This can cause some device
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* errors...
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*
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* - When single-stepping, only one instruction of the current thread is
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* executed, but interrupts are allowed for that time and will be serviced
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* if pending. Be prepared for that.
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*
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* - All debugging happens in kernel virtual address space. There's no way to
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* access physical memory not mapped in kernel space, or to access user
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* space. A way to work around this is using get_user_long & Co. in gdb
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* expressions, but only for the current process.
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*
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* - Interrupting the kernel only works if interrupts are currently allowed,
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* and the interrupt of the serial line isn't blocked by some other means
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* (IPL too high, disabled, ...)
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*
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* - The gdb stub is currently not reentrant, i.e. errors that happen therein
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* (e.g. accessing invalid memory) may not be caught correctly. This could
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* be removed in future by introducing a stack of struct registers.
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*
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*/
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/*
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* To enable debugger support, two things need to happen. One, a
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* call to kgdb_init() is necessary in order to allow any breakpoints
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* or error conditions to be properly intercepted and reported to gdb.
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* Two, a breakpoint needs to be generated to begin communication. This
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* is most easily accomplished by a call to breakpoint().
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*
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* The following gdb commands are supported:
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*
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* command function Return value
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*
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* g return the value of the CPU registers hex data or ENN
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* G set the value of the CPU registers OK or ENN
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*
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* mAA..AA,LLLL Read LLLL bytes at address AA..AA hex data or ENN
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* MAA..AA,LLLL: Write LLLL bytes at address AA.AA OK or ENN
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*
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* c Resume at current address SNN ( signal NN)
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* cAA..AA Continue at address AA..AA SNN
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*
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* s Step one instruction SNN
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* sAA..AA Step one instruction from AA..AA SNN
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*
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* k kill
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*
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* ? What was the last sigval ? SNN (signal NN)
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*
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* bBB..BB Set baud rate to BB..BB OK or BNN, then sets
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* baud rate
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*
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* All commands and responses are sent with a packet which includes a
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* checksum. A packet consists of
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*
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* $<packet info>#<checksum>.
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*
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* where
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* <packet info> :: <characters representing the command or response>
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* <checksum> :: < two hex digits computed as modulo 256 sum of <packetinfo>>
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*
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* When a packet is received, it is first acknowledged with either '+' or '-'.
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* '+' indicates a successful transfer. '-' indicates a failed transfer.
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*
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* Example:
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*
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* Host: Reply:
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* $m0,10#2a +$00010203040506070809101112131415#42
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*
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*/
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#include <linux/string.h>
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#include <linux/signal.h>
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#include <linux/kernel.h>
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#include <linux/delay.h>
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#include <linux/linkage.h>
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#include <linux/reboot.h>
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#include <asm/setup.h>
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#include <asm/ptrace.h>
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#include <asm/irq.h>
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#include <hwregs/reg_map.h>
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#include <hwregs/reg_rdwr.h>
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#include <hwregs/intr_vect_defs.h>
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#include <hwregs/ser_defs.h>
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/* From entry.S. */
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extern void gdb_handle_exception(void);
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/* From kgdb_asm.S. */
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extern void kgdb_handle_exception(void);
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static int kgdb_started = 0;
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/********************************* Register image ****************************/
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typedef
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struct register_image
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{
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/* Offset */
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unsigned int r0; /* 0x00 */
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unsigned int r1; /* 0x04 */
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unsigned int r2; /* 0x08 */
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unsigned int r3; /* 0x0C */
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unsigned int r4; /* 0x10 */
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unsigned int r5; /* 0x14 */
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unsigned int r6; /* 0x18 */
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unsigned int r7; /* 0x1C */
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unsigned int r8; /* 0x20; Frame pointer (if any) */
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unsigned int r9; /* 0x24 */
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unsigned int r10; /* 0x28 */
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unsigned int r11; /* 0x2C */
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unsigned int r12; /* 0x30 */
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unsigned int r13; /* 0x34 */
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unsigned int sp; /* 0x38; R14, Stack pointer */
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unsigned int acr; /* 0x3C; R15, Address calculation register. */
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unsigned char bz; /* 0x40; P0, 8-bit zero register */
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unsigned char vr; /* 0x41; P1, Version register (8-bit) */
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unsigned int pid; /* 0x42; P2, Process ID */
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unsigned char srs; /* 0x46; P3, Support register select (8-bit) */
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unsigned short wz; /* 0x47; P4, 16-bit zero register */
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unsigned int exs; /* 0x49; P5, Exception status */
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unsigned int eda; /* 0x4D; P6, Exception data address */
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unsigned int mof; /* 0x51; P7, Multiply overflow register */
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unsigned int dz; /* 0x55; P8, 32-bit zero register */
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unsigned int ebp; /* 0x59; P9, Exception base pointer */
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unsigned int erp; /* 0x5D; P10, Exception return pointer. Contains the PC we are interested in. */
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unsigned int srp; /* 0x61; P11, Subroutine return pointer */
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unsigned int nrp; /* 0x65; P12, NMI return pointer */
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unsigned int ccs; /* 0x69; P13, Condition code stack */
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unsigned int usp; /* 0x6D; P14, User mode stack pointer */
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unsigned int spc; /* 0x71; P15, Single step PC */
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unsigned int pc; /* 0x75; Pseudo register (for the most part set to ERP). */
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} registers;
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typedef
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struct bp_register_image
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{
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/* Support register bank 0. */
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unsigned int s0_0;
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unsigned int s1_0;
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unsigned int s2_0;
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unsigned int s3_0;
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unsigned int s4_0;
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unsigned int s5_0;
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unsigned int s6_0;
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unsigned int s7_0;
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unsigned int s8_0;
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unsigned int s9_0;
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unsigned int s10_0;
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unsigned int s11_0;
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unsigned int s12_0;
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unsigned int s13_0;
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unsigned int s14_0;
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unsigned int s15_0;
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/* Support register bank 1. */
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unsigned int s0_1;
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unsigned int s1_1;
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unsigned int s2_1;
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unsigned int s3_1;
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unsigned int s4_1;
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unsigned int s5_1;
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unsigned int s6_1;
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unsigned int s7_1;
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unsigned int s8_1;
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unsigned int s9_1;
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unsigned int s10_1;
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unsigned int s11_1;
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unsigned int s12_1;
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unsigned int s13_1;
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unsigned int s14_1;
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unsigned int s15_1;
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/* Support register bank 2. */
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unsigned int s0_2;
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unsigned int s1_2;
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unsigned int s2_2;
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unsigned int s3_2;
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unsigned int s4_2;
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unsigned int s5_2;
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unsigned int s6_2;
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unsigned int s7_2;
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unsigned int s8_2;
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unsigned int s9_2;
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unsigned int s10_2;
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unsigned int s11_2;
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unsigned int s12_2;
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unsigned int s13_2;
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unsigned int s14_2;
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unsigned int s15_2;
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/* Support register bank 3. */
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unsigned int s0_3; /* BP_CTRL */
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unsigned int s1_3; /* BP_I0_START */
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unsigned int s2_3; /* BP_I0_END */
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unsigned int s3_3; /* BP_D0_START */
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unsigned int s4_3; /* BP_D0_END */
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unsigned int s5_3; /* BP_D1_START */
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unsigned int s6_3; /* BP_D1_END */
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unsigned int s7_3; /* BP_D2_START */
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unsigned int s8_3; /* BP_D2_END */
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unsigned int s9_3; /* BP_D3_START */
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unsigned int s10_3; /* BP_D3_END */
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unsigned int s11_3; /* BP_D4_START */
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unsigned int s12_3; /* BP_D4_END */
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unsigned int s13_3; /* BP_D5_START */
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unsigned int s14_3; /* BP_D5_END */
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unsigned int s15_3; /* BP_RESERVED */
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} support_registers;
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enum register_name
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{
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R0, R1, R2, R3,
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R4, R5, R6, R7,
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R8, R9, R10, R11,
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R12, R13, SP, ACR,
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BZ, VR, PID, SRS,
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WZ, EXS, EDA, MOF,
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DZ, EBP, ERP, SRP,
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NRP, CCS, USP, SPC,
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PC,
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S0, S1, S2, S3,
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S4, S5, S6, S7,
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S8, S9, S10, S11,
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S12, S13, S14, S15
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};
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/* The register sizes of the registers in register_name. An unimplemented register
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is designated by size 0 in this array. */
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static int register_size[] =
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{
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4, 4, 4, 4,
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4, 4, 4, 4,
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4, 4, 4, 4,
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4, 4, 4, 4,
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1, 1, 4, 1,
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2, 4, 4, 4,
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4, 4, 4, 4,
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4, 4, 4, 4,
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4,
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4, 4, 4, 4,
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4, 4, 4, 4,
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4, 4, 4, 4,
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4, 4, 4
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};
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/* Contains the register image of the kernel.
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(Global so that they can be reached from assembler code.) */
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registers reg;
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support_registers sreg;
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/************** Prototypes for local library functions ***********************/
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/* Copy of strcpy from libc. */
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static char *gdb_cris_strcpy(char *s1, const char *s2);
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/* Copy of strlen from libc. */
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static int gdb_cris_strlen(const char *s);
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/* Copy of memchr from libc. */
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static void *gdb_cris_memchr(const void *s, int c, int n);
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/* Copy of strtol from libc. Does only support base 16. */
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static int gdb_cris_strtol(const char *s, char **endptr, int base);
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/********************** Prototypes for local functions. **********************/
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/* Write a value to a specified register regno in the register image
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of the current thread. */
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static int write_register(int regno, char *val);
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/* Read a value from a specified register in the register image. Returns the
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status of the read operation. The register value is returned in valptr. */
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static int read_register(char regno, unsigned int *valptr);
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/* Serial port, reads one character. ETRAX 100 specific. from debugport.c */
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int getDebugChar(void);
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#ifdef CONFIG_ETRAX_VCS_SIM
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int getDebugChar(void)
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{
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return socketread();
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}
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#endif
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/* Serial port, writes one character. ETRAX 100 specific. from debugport.c */
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void putDebugChar(int val);
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#ifdef CONFIG_ETRAX_VCS_SIM
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void putDebugChar(int val)
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{
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socketwrite((char *)&val, 1);
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}
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#endif
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/* Returns the integer equivalent of a hexadecimal character. */
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static int hex(char ch);
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/* Convert the memory, pointed to by mem into hexadecimal representation.
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Put the result in buf, and return a pointer to the last character
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in buf (null). */
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static char *mem2hex(char *buf, unsigned char *mem, int count);
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/* Convert the array, in hexadecimal representation, pointed to by buf into
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binary representation. Put the result in mem, and return a pointer to
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the character after the last byte written. */
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static unsigned char *hex2mem(unsigned char *mem, char *buf, int count);
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/* Put the content of the array, in binary representation, pointed to by buf
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into memory pointed to by mem, and return a pointer to
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the character after the last byte written. */
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static unsigned char *bin2mem(unsigned char *mem, unsigned char *buf, int count);
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/* Await the sequence $<data>#<checksum> and store <data> in the array buffer
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returned. */
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static void getpacket(char *buffer);
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/* Send $<data>#<checksum> from the <data> in the array buffer. */
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static void putpacket(char *buffer);
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/* Build and send a response packet in order to inform the host the
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stub is stopped. */
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static void stub_is_stopped(int sigval);
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/* All expected commands are sent from remote.c. Send a response according
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to the description in remote.c. Not static since it needs to be reached
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from assembler code. */
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void handle_exception(int sigval);
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/* Performs a complete re-start from scratch. ETRAX specific. */
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static void kill_restart(void);
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/******************** Prototypes for global functions. ***********************/
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/* The string str is prepended with the GDB printout token and sent. */
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void putDebugString(const unsigned char *str, int len);
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/* A static breakpoint to be used at startup. */
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void breakpoint(void);
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/* Avoid warning as the internal_stack is not used in the C-code. */
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#define USEDVAR(name) { if (name) { ; } }
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#define USEDFUN(name) { void (*pf)(void) = (void *)name; USEDVAR(pf) }
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/********************************** Packet I/O ******************************/
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/* BUFMAX defines the maximum number of characters in
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inbound/outbound buffers */
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/* FIXME: How do we know it's enough? */
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#define BUFMAX 512
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/* Run-length encoding maximum length. Send 64 at most. */
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#define RUNLENMAX 64
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/* The inbound/outbound buffers used in packet I/O */
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static char input_buffer[BUFMAX];
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static char output_buffer[BUFMAX];
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/* Error and warning messages. */
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enum error_type
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{
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SUCCESS, E01, E02, E03, E04, E05, E06,
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};
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static char *error_message[] =
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{
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"",
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"E01 Set current or general thread - H[c,g] - internal error.",
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"E02 Change register content - P - cannot change read-only register.",
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"E03 Thread is not alive.", /* T, not used. */
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"E04 The command is not supported - [s,C,S,!,R,d,r] - internal error.",
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"E05 Change register content - P - the register is not implemented..",
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"E06 Change memory content - M - internal error.",
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};
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/********************************** Breakpoint *******************************/
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|
/* Use an internal stack in the breakpoint and interrupt response routines.
|
|
FIXME: How do we know the size of this stack is enough?
|
|
Global so it can be reached from assembler code. */
|
|
#define INTERNAL_STACK_SIZE 1024
|
|
char internal_stack[INTERNAL_STACK_SIZE];
|
|
|
|
/* Due to the breakpoint return pointer, a state variable is needed to keep
|
|
track of whether it is a static (compiled) or dynamic (gdb-invoked)
|
|
breakpoint to be handled. A static breakpoint uses the content of register
|
|
ERP as it is whereas a dynamic breakpoint requires subtraction with 2
|
|
in order to execute the instruction. The first breakpoint is static; all
|
|
following are assumed to be dynamic. */
|
|
static int dynamic_bp = 0;
|
|
|
|
/********************************* String library ****************************/
|
|
/* Single-step over library functions creates trap loops. */
|
|
|
|
/* Copy char s2[] to s1[]. */
|
|
static char*
|
|
gdb_cris_strcpy(char *s1, const char *s2)
|
|
{
|
|
char *s = s1;
|
|
|
|
for (s = s1; (*s++ = *s2++) != '\0'; )
|
|
;
|
|
return s1;
|
|
}
|
|
|
|
/* Find length of s[]. */
|
|
static int
|
|
gdb_cris_strlen(const char *s)
|
|
{
|
|
const char *sc;
|
|
|
|
for (sc = s; *sc != '\0'; sc++)
|
|
;
|
|
return (sc - s);
|
|
}
|
|
|
|
/* Find first occurrence of c in s[n]. */
|
|
static void*
|
|
gdb_cris_memchr(const void *s, int c, int n)
|
|
{
|
|
const unsigned char uc = c;
|
|
const unsigned char *su;
|
|
|
|
for (su = s; 0 < n; ++su, --n)
|
|
if (*su == uc)
|
|
return (void *)su;
|
|
return NULL;
|
|
}
|
|
/******************************* Standard library ****************************/
|
|
/* Single-step over library functions creates trap loops. */
|
|
/* Convert string to long. */
|
|
static int
|
|
gdb_cris_strtol(const char *s, char **endptr, int base)
|
|
{
|
|
char *s1;
|
|
char *sd;
|
|
int x = 0;
|
|
|
|
for (s1 = (char*)s; (sd = gdb_cris_memchr(hex_asc, *s1, base)) != NULL; ++s1)
|
|
x = x * base + (sd - hex_asc);
|
|
|
|
if (endptr) {
|
|
/* Unconverted suffix is stored in endptr unless endptr is NULL. */
|
|
*endptr = s1;
|
|
}
|
|
|
|
return x;
|
|
}
|
|
|
|
/********************************* Register image ****************************/
|
|
|
|
/* Write a value to a specified register in the register image of the current
|
|
thread. Returns status code SUCCESS, E02 or E05. */
|
|
static int
|
|
write_register(int regno, char *val)
|
|
{
|
|
int status = SUCCESS;
|
|
|
|
if (regno >= R0 && regno <= ACR) {
|
|
/* Consecutive 32-bit registers. */
|
|
hex2mem((unsigned char *)®.r0 + (regno - R0) * sizeof(unsigned int),
|
|
val, sizeof(unsigned int));
|
|
|
|
} else if (regno == BZ || regno == VR || regno == WZ || regno == DZ) {
|
|
/* Read-only registers. */
|
|
status = E02;
|
|
|
|
} else if (regno == PID) {
|
|
/* 32-bit register. (Even though we already checked SRS and WZ, we cannot
|
|
combine this with the EXS - SPC write since SRS and WZ have different size.) */
|
|
hex2mem((unsigned char *)®.pid, val, sizeof(unsigned int));
|
|
|
|
} else if (regno == SRS) {
|
|
/* 8-bit register. */
|
|
hex2mem((unsigned char *)®.srs, val, sizeof(unsigned char));
|
|
|
|
} else if (regno >= EXS && regno <= SPC) {
|
|
/* Consecutive 32-bit registers. */
|
|
hex2mem((unsigned char *)®.exs + (regno - EXS) * sizeof(unsigned int),
|
|
val, sizeof(unsigned int));
|
|
|
|
} else if (regno == PC) {
|
|
/* Pseudo-register. Treat as read-only. */
|
|
status = E02;
|
|
|
|
} else if (regno >= S0 && regno <= S15) {
|
|
/* 32-bit registers. */
|
|
hex2mem((unsigned char *)&sreg.s0_0 + (reg.srs * 16 * sizeof(unsigned int)) + (regno - S0) * sizeof(unsigned int), val, sizeof(unsigned int));
|
|
} else {
|
|
/* Non-existing register. */
|
|
status = E05;
|
|
}
|
|
return status;
|
|
}
|
|
|
|
/* Read a value from a specified register in the register image. Returns the
|
|
value in the register or -1 for non-implemented registers. */
|
|
static int
|
|
read_register(char regno, unsigned int *valptr)
|
|
{
|
|
int status = SUCCESS;
|
|
|
|
/* We read the zero registers from the register struct (instead of just returning 0)
|
|
to catch errors. */
|
|
|
|
if (regno >= R0 && regno <= ACR) {
|
|
/* Consecutive 32-bit registers. */
|
|
*valptr = *(unsigned int *)((char *)®.r0 + (regno - R0) * sizeof(unsigned int));
|
|
|
|
} else if (regno == BZ || regno == VR) {
|
|
/* Consecutive 8-bit registers. */
|
|
*valptr = (unsigned int)(*(unsigned char *)
|
|
((char *)®.bz + (regno - BZ) * sizeof(char)));
|
|
|
|
} else if (regno == PID) {
|
|
/* 32-bit register. */
|
|
*valptr = *(unsigned int *)((char *)®.pid);
|
|
|
|
} else if (regno == SRS) {
|
|
/* 8-bit register. */
|
|
*valptr = (unsigned int)(*(unsigned char *)((char *)®.srs));
|
|
|
|
} else if (regno == WZ) {
|
|
/* 16-bit register. */
|
|
*valptr = (unsigned int)(*(unsigned short *)(char *)®.wz);
|
|
|
|
} else if (regno >= EXS && regno <= PC) {
|
|
/* Consecutive 32-bit registers. */
|
|
*valptr = *(unsigned int *)((char *)®.exs + (regno - EXS) * sizeof(unsigned int));
|
|
|
|
} else if (regno >= S0 && regno <= S15) {
|
|
/* Consecutive 32-bit registers, located elsewhere. */
|
|
*valptr = *(unsigned int *)((char *)&sreg.s0_0 + (reg.srs * 16 * sizeof(unsigned int)) + (regno - S0) * sizeof(unsigned int));
|
|
|
|
} else {
|
|
/* Non-existing register. */
|
|
status = E05;
|
|
}
|
|
return status;
|
|
|
|
}
|
|
|
|
/********************************** Packet I/O ******************************/
|
|
/* Returns the integer equivalent of a hexadecimal character. */
|
|
static int
|
|
hex(char ch)
|
|
{
|
|
if ((ch >= 'a') && (ch <= 'f'))
|
|
return (ch - 'a' + 10);
|
|
if ((ch >= '0') && (ch <= '9'))
|
|
return (ch - '0');
|
|
if ((ch >= 'A') && (ch <= 'F'))
|
|
return (ch - 'A' + 10);
|
|
return -1;
|
|
}
|
|
|
|
/* Convert the memory, pointed to by mem into hexadecimal representation.
|
|
Put the result in buf, and return a pointer to the last character
|
|
in buf (null). */
|
|
|
|
static char *
|
|
mem2hex(char *buf, unsigned char *mem, int count)
|
|
{
|
|
int i;
|
|
int ch;
|
|
|
|
if (mem == NULL) {
|
|
/* Invalid address, caught by 'm' packet handler. */
|
|
for (i = 0; i < count; i++) {
|
|
*buf++ = '0';
|
|
*buf++ = '0';
|
|
}
|
|
} else {
|
|
/* Valid mem address. */
|
|
for (i = 0; i < count; i++) {
|
|
ch = *mem++;
|
|
buf = hex_byte_pack(buf, ch);
|
|
}
|
|
}
|
|
/* Terminate properly. */
|
|
*buf = '\0';
|
|
return buf;
|
|
}
|
|
|
|
/* Same as mem2hex, but puts it in network byte order. */
|
|
static char *
|
|
mem2hex_nbo(char *buf, unsigned char *mem, int count)
|
|
{
|
|
int i;
|
|
int ch;
|
|
|
|
mem += count - 1;
|
|
for (i = 0; i < count; i++) {
|
|
ch = *mem--;
|
|
buf = hex_byte_pack(buf, ch);
|
|
}
|
|
|
|
/* Terminate properly. */
|
|
*buf = '\0';
|
|
return buf;
|
|
}
|
|
|
|
/* Convert the array, in hexadecimal representation, pointed to by buf into
|
|
binary representation. Put the result in mem, and return a pointer to
|
|
the character after the last byte written. */
|
|
static unsigned char*
|
|
hex2mem(unsigned char *mem, char *buf, int count)
|
|
{
|
|
int i;
|
|
unsigned char ch;
|
|
for (i = 0; i < count; i++) {
|
|
ch = hex (*buf++) << 4;
|
|
ch = ch + hex (*buf++);
|
|
*mem++ = ch;
|
|
}
|
|
return mem;
|
|
}
|
|
|
|
/* Put the content of the array, in binary representation, pointed to by buf
|
|
into memory pointed to by mem, and return a pointer to the character after
|
|
the last byte written.
|
|
Gdb will escape $, #, and the escape char (0x7d). */
|
|
static unsigned char*
|
|
bin2mem(unsigned char *mem, unsigned char *buf, int count)
|
|
{
|
|
int i;
|
|
unsigned char *next;
|
|
for (i = 0; i < count; i++) {
|
|
/* Check for any escaped characters. Be paranoid and
|
|
only unescape chars that should be escaped. */
|
|
if (*buf == 0x7d) {
|
|
next = buf + 1;
|
|
if (*next == 0x3 || *next == 0x4 || *next == 0x5D) {
|
|
/* #, $, ESC */
|
|
buf++;
|
|
*buf += 0x20;
|
|
}
|
|
}
|
|
*mem++ = *buf++;
|
|
}
|
|
return mem;
|
|
}
|
|
|
|
/* Await the sequence $<data>#<checksum> and store <data> in the array buffer
|
|
returned. */
|
|
static void
|
|
getpacket(char *buffer)
|
|
{
|
|
unsigned char checksum;
|
|
unsigned char xmitcsum;
|
|
int i;
|
|
int count;
|
|
char ch;
|
|
|
|
do {
|
|
while((ch = getDebugChar ()) != '$')
|
|
/* Wait for the start character $ and ignore all other characters */;
|
|
checksum = 0;
|
|
xmitcsum = -1;
|
|
count = 0;
|
|
/* Read until a # or the end of the buffer is reached */
|
|
while (count < BUFMAX) {
|
|
ch = getDebugChar();
|
|
if (ch == '#')
|
|
break;
|
|
checksum = checksum + ch;
|
|
buffer[count] = ch;
|
|
count = count + 1;
|
|
}
|
|
|
|
if (count >= BUFMAX)
|
|
continue;
|
|
|
|
buffer[count] = 0;
|
|
|
|
if (ch == '#') {
|
|
xmitcsum = hex(getDebugChar()) << 4;
|
|
xmitcsum += hex(getDebugChar());
|
|
if (checksum != xmitcsum) {
|
|
/* Wrong checksum */
|
|
putDebugChar('-');
|
|
} else {
|
|
/* Correct checksum */
|
|
putDebugChar('+');
|
|
/* If sequence characters are received, reply with them */
|
|
if (buffer[2] == ':') {
|
|
putDebugChar(buffer[0]);
|
|
putDebugChar(buffer[1]);
|
|
/* Remove the sequence characters from the buffer */
|
|
count = gdb_cris_strlen(buffer);
|
|
for (i = 3; i <= count; i++)
|
|
buffer[i - 3] = buffer[i];
|
|
}
|
|
}
|
|
}
|
|
} while (checksum != xmitcsum);
|
|
}
|
|
|
|
/* Send $<data>#<checksum> from the <data> in the array buffer. */
|
|
|
|
static void
|
|
putpacket(char *buffer)
|
|
{
|
|
int checksum;
|
|
int runlen;
|
|
int encode;
|
|
|
|
do {
|
|
char *src = buffer;
|
|
putDebugChar('$');
|
|
checksum = 0;
|
|
while (*src) {
|
|
/* Do run length encoding */
|
|
putDebugChar(*src);
|
|
checksum += *src;
|
|
runlen = 0;
|
|
while (runlen < RUNLENMAX && *src == src[runlen]) {
|
|
runlen++;
|
|
}
|
|
if (runlen > 3) {
|
|
/* Got a useful amount */
|
|
putDebugChar ('*');
|
|
checksum += '*';
|
|
encode = runlen + ' ' - 4;
|
|
putDebugChar(encode);
|
|
checksum += encode;
|
|
src += runlen;
|
|
} else {
|
|
src++;
|
|
}
|
|
}
|
|
putDebugChar('#');
|
|
putDebugChar(hex_asc_hi(checksum));
|
|
putDebugChar(hex_asc_lo(checksum));
|
|
} while(kgdb_started && (getDebugChar() != '+'));
|
|
}
|
|
|
|
/* The string str is prepended with the GDB printout token and sent. Required
|
|
in traditional implementations. */
|
|
void
|
|
putDebugString(const unsigned char *str, int len)
|
|
{
|
|
/* Move SPC forward if we are single-stepping. */
|
|
asm("spchere:");
|
|
asm("move $spc, $r10");
|
|
asm("cmp.d spchere, $r10");
|
|
asm("bne nosstep");
|
|
asm("nop");
|
|
asm("move.d spccont, $r10");
|
|
asm("move $r10, $spc");
|
|
asm("nosstep:");
|
|
|
|
output_buffer[0] = 'O';
|
|
mem2hex(&output_buffer[1], (unsigned char *)str, len);
|
|
putpacket(output_buffer);
|
|
|
|
asm("spccont:");
|
|
}
|
|
|
|
/********************************** Handle exceptions ************************/
|
|
/* Build and send a response packet in order to inform the host the
|
|
stub is stopped. TAAn...:r...;n...:r...;n...:r...;
|
|
AA = signal number
|
|
n... = register number (hex)
|
|
r... = register contents
|
|
n... = `thread'
|
|
r... = thread process ID. This is a hex integer.
|
|
n... = other string not starting with valid hex digit.
|
|
gdb should ignore this n,r pair and go on to the next.
|
|
This way we can extend the protocol. */
|
|
static void
|
|
stub_is_stopped(int sigval)
|
|
{
|
|
char *ptr = output_buffer;
|
|
unsigned int reg_cont;
|
|
|
|
/* Send trap type (converted to signal) */
|
|
|
|
*ptr++ = 'T';
|
|
ptr = hex_byte_pack(ptr, sigval);
|
|
|
|
if (((reg.exs & 0xff00) >> 8) == 0xc) {
|
|
|
|
/* Some kind of hardware watchpoint triggered. Find which one
|
|
and determine its type (read/write/access). */
|
|
int S, bp, trig_bits = 0, rw_bits = 0;
|
|
int trig_mask = 0;
|
|
unsigned int *bp_d_regs = &sreg.s3_3;
|
|
/* In a lot of cases, the stopped data address will simply be EDA.
|
|
In some cases, we adjust it to match the watched data range.
|
|
(We don't want to change the actual EDA though). */
|
|
unsigned int stopped_data_address;
|
|
/* The S field of EXS. */
|
|
S = (reg.exs & 0xffff0000) >> 16;
|
|
|
|
if (S & 1) {
|
|
/* Instruction watchpoint. */
|
|
/* FIXME: Check against, and possibly adjust reported EDA. */
|
|
} else {
|
|
/* Data watchpoint. Find the one that triggered. */
|
|
for (bp = 0; bp < 6; bp++) {
|
|
|
|
/* Dx_RD, Dx_WR in the S field of EXS for this BP. */
|
|
int bitpos_trig = 1 + bp * 2;
|
|
/* Dx_BPRD, Dx_BPWR in BP_CTRL for this BP. */
|
|
int bitpos_config = 2 + bp * 4;
|
|
|
|
/* Get read/write trig bits for this BP. */
|
|
trig_bits = (S & (3 << bitpos_trig)) >> bitpos_trig;
|
|
|
|
/* Read/write config bits for this BP. */
|
|
rw_bits = (sreg.s0_3 & (3 << bitpos_config)) >> bitpos_config;
|
|
if (trig_bits) {
|
|
/* Sanity check: the BP shouldn't trigger for accesses
|
|
that it isn't configured for. */
|
|
if ((rw_bits == 0x1 && trig_bits != 0x1) ||
|
|
(rw_bits == 0x2 && trig_bits != 0x2))
|
|
panic("Invalid r/w trigging for this BP");
|
|
|
|
/* Mark this BP as trigged for future reference. */
|
|
trig_mask |= (1 << bp);
|
|
|
|
if (reg.eda >= bp_d_regs[bp * 2] &&
|
|
reg.eda <= bp_d_regs[bp * 2 + 1]) {
|
|
/* EDA within range for this BP; it must be the one
|
|
we're looking for. */
|
|
stopped_data_address = reg.eda;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if (bp < 6) {
|
|
/* Found a trigged BP with EDA within its configured data range. */
|
|
} else if (trig_mask) {
|
|
/* Something triggered, but EDA doesn't match any BP's range. */
|
|
for (bp = 0; bp < 6; bp++) {
|
|
/* Dx_BPRD, Dx_BPWR in BP_CTRL for this BP. */
|
|
int bitpos_config = 2 + bp * 4;
|
|
|
|
/* Read/write config bits for this BP (needed later). */
|
|
rw_bits = (sreg.s0_3 & (3 << bitpos_config)) >> bitpos_config;
|
|
|
|
if (trig_mask & (1 << bp)) {
|
|
/* EDA within 31 bytes of the configured start address? */
|
|
if (reg.eda + 31 >= bp_d_regs[bp * 2]) {
|
|
/* Changing the reported address to match
|
|
the start address of the first applicable BP. */
|
|
stopped_data_address = bp_d_regs[bp * 2];
|
|
break;
|
|
} else {
|
|
/* We continue since we might find another useful BP. */
|
|
printk("EDA doesn't match trigged BP's range");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/* No match yet? */
|
|
BUG_ON(bp >= 6);
|
|
/* Note that we report the type according to what the BP is configured
|
|
for (otherwise we'd never report an 'awatch'), not according to how
|
|
it trigged. We did check that the trigged bits match what the BP is
|
|
configured for though. */
|
|
if (rw_bits == 0x1) {
|
|
/* read */
|
|
strncpy(ptr, "rwatch", 6);
|
|
ptr += 6;
|
|
} else if (rw_bits == 0x2) {
|
|
/* write */
|
|
strncpy(ptr, "watch", 5);
|
|
ptr += 5;
|
|
} else if (rw_bits == 0x3) {
|
|
/* access */
|
|
strncpy(ptr, "awatch", 6);
|
|
ptr += 6;
|
|
} else {
|
|
panic("Invalid r/w bits for this BP.");
|
|
}
|
|
|
|
*ptr++ = ':';
|
|
/* Note that we don't read_register(EDA, ...) */
|
|
ptr = mem2hex_nbo(ptr, (unsigned char *)&stopped_data_address, register_size[EDA]);
|
|
*ptr++ = ';';
|
|
}
|
|
}
|
|
/* Only send PC, frame and stack pointer. */
|
|
read_register(PC, ®_cont);
|
|
ptr = hex_byte_pack(ptr, PC);
|
|
*ptr++ = ':';
|
|
ptr = mem2hex(ptr, (unsigned char *)®_cont, register_size[PC]);
|
|
*ptr++ = ';';
|
|
|
|
read_register(R8, ®_cont);
|
|
ptr = hex_byte_pack(ptr, R8);
|
|
*ptr++ = ':';
|
|
ptr = mem2hex(ptr, (unsigned char *)®_cont, register_size[R8]);
|
|
*ptr++ = ';';
|
|
|
|
read_register(SP, ®_cont);
|
|
ptr = hex_byte_pack(ptr, SP);
|
|
*ptr++ = ':';
|
|
ptr = mem2hex(ptr, (unsigned char *)®_cont, register_size[SP]);
|
|
*ptr++ = ';';
|
|
|
|
/* Send ERP as well; this will save us an entire register fetch in some cases. */
|
|
read_register(ERP, ®_cont);
|
|
ptr = hex_byte_pack(ptr, ERP);
|
|
*ptr++ = ':';
|
|
ptr = mem2hex(ptr, (unsigned char *)®_cont, register_size[ERP]);
|
|
*ptr++ = ';';
|
|
|
|
/* null-terminate and send it off */
|
|
*ptr = 0;
|
|
putpacket(output_buffer);
|
|
}
|
|
|
|
/* Returns the size of an instruction that has a delay slot. */
|
|
|
|
int insn_size(unsigned long pc)
|
|
{
|
|
unsigned short opcode = *(unsigned short *)pc;
|
|
int size = 0;
|
|
|
|
switch ((opcode & 0x0f00) >> 8) {
|
|
case 0x0:
|
|
case 0x9:
|
|
case 0xb:
|
|
size = 2;
|
|
break;
|
|
case 0xe:
|
|
case 0xf:
|
|
size = 6;
|
|
break;
|
|
case 0xd:
|
|
/* Could be 4 or 6; check more bits. */
|
|
if ((opcode & 0xff) == 0xff)
|
|
size = 4;
|
|
else
|
|
size = 6;
|
|
break;
|
|
default:
|
|
panic("Couldn't find size of opcode 0x%x at 0x%lx\n", opcode, pc);
|
|
}
|
|
|
|
return size;
|
|
}
|
|
|
|
void register_fixup(int sigval)
|
|
{
|
|
/* Compensate for ACR push at the beginning of exception handler. */
|
|
reg.sp += 4;
|
|
|
|
/* Standard case. */
|
|
reg.pc = reg.erp;
|
|
if (reg.erp & 0x1) {
|
|
/* Delay slot bit set. Report as stopped on proper instruction. */
|
|
if (reg.spc) {
|
|
/* Rely on SPC if set. */
|
|
reg.pc = reg.spc;
|
|
} else {
|
|
/* Calculate the PC from the size of the instruction
|
|
that the delay slot we're in belongs to. */
|
|
reg.pc += insn_size(reg.erp & ~1) - 1 ;
|
|
}
|
|
}
|
|
|
|
if ((reg.exs & 0x3) == 0x0) {
|
|
/* Bits 1 - 0 indicate the type of memory operation performed
|
|
by the interrupted instruction. 0 means no memory operation,
|
|
and EDA is undefined in that case. We zero it to avoid confusion. */
|
|
reg.eda = 0;
|
|
}
|
|
|
|
if (sigval == SIGTRAP) {
|
|
/* Break 8, single step or hardware breakpoint exception. */
|
|
|
|
/* Check IDX field of EXS. */
|
|
if (((reg.exs & 0xff00) >> 8) == 0x18) {
|
|
|
|
/* Break 8. */
|
|
|
|
/* Static (compiled) breakpoints must return to the next instruction
|
|
in order to avoid infinite loops (default value of ERP). Dynamic
|
|
(gdb-invoked) must subtract the size of the break instruction from
|
|
the ERP so that the instruction that was originally in the break
|
|
instruction's place will be run when we return from the exception. */
|
|
if (!dynamic_bp) {
|
|
/* Assuming that all breakpoints are dynamic from now on. */
|
|
dynamic_bp = 1;
|
|
} else {
|
|
|
|
/* Only if not in a delay slot. */
|
|
if (!(reg.erp & 0x1)) {
|
|
reg.erp -= 2;
|
|
reg.pc -= 2;
|
|
}
|
|
}
|
|
|
|
} else if (((reg.exs & 0xff00) >> 8) == 0x3) {
|
|
/* Single step. */
|
|
/* Don't fiddle with S1. */
|
|
|
|
} else if (((reg.exs & 0xff00) >> 8) == 0xc) {
|
|
|
|
/* Hardware watchpoint exception. */
|
|
|
|
/* SPC has been updated so that we will get a single step exception
|
|
when we return, but we don't want that. */
|
|
reg.spc = 0;
|
|
|
|
/* Don't fiddle with S1. */
|
|
}
|
|
|
|
} else if (sigval == SIGINT) {
|
|
/* Nothing special. */
|
|
}
|
|
}
|
|
|
|
static void insert_watchpoint(char type, int addr, int len)
|
|
{
|
|
/* Breakpoint/watchpoint types (GDB terminology):
|
|
0 = memory breakpoint for instructions
|
|
(not supported; done via memory write instead)
|
|
1 = hardware breakpoint for instructions (supported)
|
|
2 = write watchpoint (supported)
|
|
3 = read watchpoint (supported)
|
|
4 = access watchpoint (supported) */
|
|
|
|
if (type < '1' || type > '4') {
|
|
output_buffer[0] = 0;
|
|
return;
|
|
}
|
|
|
|
/* Read watchpoints are set as access watchpoints, because of GDB's
|
|
inability to deal with pure read watchpoints. */
|
|
if (type == '3')
|
|
type = '4';
|
|
|
|
if (type == '1') {
|
|
/* Hardware (instruction) breakpoint. */
|
|
/* Bit 0 in BP_CTRL holds the configuration for I0. */
|
|
if (sreg.s0_3 & 0x1) {
|
|
/* Already in use. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
return;
|
|
}
|
|
/* Configure. */
|
|
sreg.s1_3 = addr;
|
|
sreg.s2_3 = (addr + len - 1);
|
|
sreg.s0_3 |= 1;
|
|
} else {
|
|
int bp;
|
|
unsigned int *bp_d_regs = &sreg.s3_3;
|
|
|
|
/* The watchpoint allocation scheme is the simplest possible.
|
|
For example, if a region is watched for read and
|
|
a write watch is requested, a new watchpoint will
|
|
be used. Also, if a watch for a region that is already
|
|
covered by one or more existing watchpoints, a new
|
|
watchpoint will be used. */
|
|
|
|
/* First, find a free data watchpoint. */
|
|
for (bp = 0; bp < 6; bp++) {
|
|
/* Each data watchpoint's control registers occupy 2 bits
|
|
(hence the 3), starting at bit 2 for D0 (hence the 2)
|
|
with 4 bits between for each watchpoint (yes, the 4). */
|
|
if (!(sreg.s0_3 & (0x3 << (2 + (bp * 4))))) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (bp > 5) {
|
|
/* We're out of watchpoints. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
return;
|
|
}
|
|
|
|
/* Configure the control register first. */
|
|
if (type == '3' || type == '4') {
|
|
/* Trigger on read. */
|
|
sreg.s0_3 |= (1 << (2 + bp * 4));
|
|
}
|
|
if (type == '2' || type == '4') {
|
|
/* Trigger on write. */
|
|
sreg.s0_3 |= (2 << (2 + bp * 4));
|
|
}
|
|
|
|
/* Ugly pointer arithmetics to configure the watched range. */
|
|
bp_d_regs[bp * 2] = addr;
|
|
bp_d_regs[bp * 2 + 1] = (addr + len - 1);
|
|
}
|
|
|
|
/* Set the S1 flag to enable watchpoints. */
|
|
reg.ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT));
|
|
gdb_cris_strcpy(output_buffer, "OK");
|
|
}
|
|
|
|
static void remove_watchpoint(char type, int addr, int len)
|
|
{
|
|
/* Breakpoint/watchpoint types:
|
|
0 = memory breakpoint for instructions
|
|
(not supported; done via memory write instead)
|
|
1 = hardware breakpoint for instructions (supported)
|
|
2 = write watchpoint (supported)
|
|
3 = read watchpoint (supported)
|
|
4 = access watchpoint (supported) */
|
|
if (type < '1' || type > '4') {
|
|
output_buffer[0] = 0;
|
|
return;
|
|
}
|
|
|
|
/* Read watchpoints are set as access watchpoints, because of GDB's
|
|
inability to deal with pure read watchpoints. */
|
|
if (type == '3')
|
|
type = '4';
|
|
|
|
if (type == '1') {
|
|
/* Hardware breakpoint. */
|
|
/* Bit 0 in BP_CTRL holds the configuration for I0. */
|
|
if (!(sreg.s0_3 & 0x1)) {
|
|
/* Not in use. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
return;
|
|
}
|
|
/* Deconfigure. */
|
|
sreg.s1_3 = 0;
|
|
sreg.s2_3 = 0;
|
|
sreg.s0_3 &= ~1;
|
|
} else {
|
|
int bp;
|
|
unsigned int *bp_d_regs = &sreg.s3_3;
|
|
/* Try to find a watchpoint that is configured for the
|
|
specified range, then check that read/write also matches. */
|
|
|
|
/* Ugly pointer arithmetic, since I cannot rely on a
|
|
single switch (addr) as there may be several watchpoints with
|
|
the same start address for example. */
|
|
|
|
for (bp = 0; bp < 6; bp++) {
|
|
if (bp_d_regs[bp * 2] == addr &&
|
|
bp_d_regs[bp * 2 + 1] == (addr + len - 1)) {
|
|
/* Matching range. */
|
|
int bitpos = 2 + bp * 4;
|
|
int rw_bits;
|
|
|
|
/* Read/write bits for this BP. */
|
|
rw_bits = (sreg.s0_3 & (0x3 << bitpos)) >> bitpos;
|
|
|
|
if ((type == '3' && rw_bits == 0x1) ||
|
|
(type == '2' && rw_bits == 0x2) ||
|
|
(type == '4' && rw_bits == 0x3)) {
|
|
/* Read/write matched. */
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (bp > 5) {
|
|
/* No watchpoint matched. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
return;
|
|
}
|
|
|
|
/* Found a matching watchpoint. Now, deconfigure it by
|
|
both disabling read/write in bp_ctrl and zeroing its
|
|
start/end addresses. */
|
|
sreg.s0_3 &= ~(3 << (2 + (bp * 4)));
|
|
bp_d_regs[bp * 2] = 0;
|
|
bp_d_regs[bp * 2 + 1] = 0;
|
|
}
|
|
|
|
/* Note that we don't clear the S1 flag here. It's done when continuing. */
|
|
gdb_cris_strcpy(output_buffer, "OK");
|
|
}
|
|
|
|
|
|
|
|
/* All expected commands are sent from remote.c. Send a response according
|
|
to the description in remote.c. */
|
|
void
|
|
handle_exception(int sigval)
|
|
{
|
|
/* Avoid warning of not used. */
|
|
|
|
USEDFUN(handle_exception);
|
|
USEDVAR(internal_stack[0]);
|
|
|
|
register_fixup(sigval);
|
|
|
|
/* Send response. */
|
|
stub_is_stopped(sigval);
|
|
|
|
for (;;) {
|
|
output_buffer[0] = '\0';
|
|
getpacket(input_buffer);
|
|
switch (input_buffer[0]) {
|
|
case 'g':
|
|
/* Read registers: g
|
|
Success: Each byte of register data is described by two hex digits.
|
|
Registers are in the internal order for GDB, and the bytes
|
|
in a register are in the same order the machine uses.
|
|
Failure: void. */
|
|
{
|
|
char *buf;
|
|
/* General and special registers. */
|
|
buf = mem2hex(output_buffer, (char *)®, sizeof(registers));
|
|
/* Support registers. */
|
|
/* -1 because of the null termination that mem2hex adds. */
|
|
mem2hex(buf,
|
|
(char *)&sreg + (reg.srs * 16 * sizeof(unsigned int)),
|
|
16 * sizeof(unsigned int));
|
|
break;
|
|
}
|
|
case 'G':
|
|
/* Write registers. GXX..XX
|
|
Each byte of register data is described by two hex digits.
|
|
Success: OK
|
|
Failure: void. */
|
|
/* General and special registers. */
|
|
hex2mem((char *)®, &input_buffer[1], sizeof(registers));
|
|
/* Support registers. */
|
|
hex2mem((char *)&sreg + (reg.srs * 16 * sizeof(unsigned int)),
|
|
&input_buffer[1] + sizeof(registers),
|
|
16 * sizeof(unsigned int));
|
|
gdb_cris_strcpy(output_buffer, "OK");
|
|
break;
|
|
|
|
case 'P':
|
|
/* Write register. Pn...=r...
|
|
Write register n..., hex value without 0x, with value r...,
|
|
which contains a hex value without 0x and two hex digits
|
|
for each byte in the register (target byte order). P1f=11223344 means
|
|
set register 31 to 44332211.
|
|
Success: OK
|
|
Failure: E02, E05 */
|
|
{
|
|
char *suffix;
|
|
int regno = gdb_cris_strtol(&input_buffer[1], &suffix, 16);
|
|
int status;
|
|
|
|
status = write_register(regno, suffix+1);
|
|
|
|
switch (status) {
|
|
case E02:
|
|
/* Do not support read-only registers. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E02]);
|
|
break;
|
|
case E05:
|
|
/* Do not support non-existing registers. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E05]);
|
|
break;
|
|
default:
|
|
/* Valid register number. */
|
|
gdb_cris_strcpy(output_buffer, "OK");
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
|
|
case 'm':
|
|
/* Read from memory. mAA..AA,LLLL
|
|
AA..AA is the address and LLLL is the length.
|
|
Success: XX..XX is the memory content. Can be fewer bytes than
|
|
requested if only part of the data may be read. m6000120a,6c means
|
|
retrieve 108 byte from base address 6000120a.
|
|
Failure: void. */
|
|
{
|
|
char *suffix;
|
|
unsigned char *addr = (unsigned char *)gdb_cris_strtol(&input_buffer[1],
|
|
&suffix, 16);
|
|
int len = gdb_cris_strtol(suffix+1, 0, 16);
|
|
|
|
/* Bogus read (i.e. outside the kernel's
|
|
segment)? . */
|
|
if (!((unsigned int)addr >= 0xc0000000 &&
|
|
(unsigned int)addr < 0xd0000000))
|
|
addr = NULL;
|
|
|
|
mem2hex(output_buffer, addr, len);
|
|
}
|
|
break;
|
|
|
|
case 'X':
|
|
/* Write to memory. XAA..AA,LLLL:XX..XX
|
|
AA..AA is the start address, LLLL is the number of bytes, and
|
|
XX..XX is the binary data.
|
|
Success: OK
|
|
Failure: void. */
|
|
case 'M':
|
|
/* Write to memory. MAA..AA,LLLL:XX..XX
|
|
AA..AA is the start address, LLLL is the number of bytes, and
|
|
XX..XX is the hexadecimal data.
|
|
Success: OK
|
|
Failure: void. */
|
|
{
|
|
char *lenptr;
|
|
char *dataptr;
|
|
unsigned char *addr = (unsigned char *)gdb_cris_strtol(&input_buffer[1],
|
|
&lenptr, 16);
|
|
int len = gdb_cris_strtol(lenptr+1, &dataptr, 16);
|
|
if (*lenptr == ',' && *dataptr == ':') {
|
|
if (input_buffer[0] == 'M') {
|
|
hex2mem(addr, dataptr + 1, len);
|
|
} else /* X */ {
|
|
bin2mem(addr, dataptr + 1, len);
|
|
}
|
|
gdb_cris_strcpy(output_buffer, "OK");
|
|
}
|
|
else {
|
|
gdb_cris_strcpy(output_buffer, error_message[E06]);
|
|
}
|
|
}
|
|
break;
|
|
|
|
case 'c':
|
|
/* Continue execution. cAA..AA
|
|
AA..AA is the address where execution is resumed. If AA..AA is
|
|
omitted, resume at the present address.
|
|
Success: return to the executing thread.
|
|
Failure: will never know. */
|
|
|
|
if (input_buffer[1] != '\0') {
|
|
/* FIXME: Doesn't handle address argument. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
break;
|
|
}
|
|
|
|
/* Before continuing, make sure everything is set up correctly. */
|
|
|
|
/* Set the SPC to some unlikely value. */
|
|
reg.spc = 0;
|
|
/* Set the S1 flag to 0 unless some watchpoint is enabled (since setting
|
|
S1 to 0 would also disable watchpoints). (Note that bits 26-31 in BP_CTRL
|
|
are reserved, so don't check against those). */
|
|
if ((sreg.s0_3 & 0x3fff) == 0) {
|
|
reg.ccs &= ~(1 << (S_CCS_BITNR + CCS_SHIFT));
|
|
}
|
|
|
|
return;
|
|
|
|
case 's':
|
|
/* Step. sAA..AA
|
|
AA..AA is the address where execution is resumed. If AA..AA is
|
|
omitted, resume at the present address. Success: return to the
|
|
executing thread. Failure: will never know. */
|
|
|
|
if (input_buffer[1] != '\0') {
|
|
/* FIXME: Doesn't handle address argument. */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
break;
|
|
}
|
|
|
|
/* Set the SPC to PC, which is where we'll return
|
|
(deduced previously). */
|
|
reg.spc = reg.pc;
|
|
|
|
/* Set the S1 (first stacked, not current) flag, which will
|
|
kick into action when we rfe. */
|
|
reg.ccs |= (1 << (S_CCS_BITNR + CCS_SHIFT));
|
|
return;
|
|
|
|
case 'Z':
|
|
|
|
/* Insert breakpoint or watchpoint, Ztype,addr,length.
|
|
Remote protocol says: A remote target shall return an empty string
|
|
for an unrecognized breakpoint or watchpoint packet type. */
|
|
{
|
|
char *lenptr;
|
|
char *dataptr;
|
|
int addr = gdb_cris_strtol(&input_buffer[3], &lenptr, 16);
|
|
int len = gdb_cris_strtol(lenptr + 1, &dataptr, 16);
|
|
char type = input_buffer[1];
|
|
|
|
insert_watchpoint(type, addr, len);
|
|
break;
|
|
}
|
|
|
|
case 'z':
|
|
/* Remove breakpoint or watchpoint, Ztype,addr,length.
|
|
Remote protocol says: A remote target shall return an empty string
|
|
for an unrecognized breakpoint or watchpoint packet type. */
|
|
{
|
|
char *lenptr;
|
|
char *dataptr;
|
|
int addr = gdb_cris_strtol(&input_buffer[3], &lenptr, 16);
|
|
int len = gdb_cris_strtol(lenptr + 1, &dataptr, 16);
|
|
char type = input_buffer[1];
|
|
|
|
remove_watchpoint(type, addr, len);
|
|
break;
|
|
}
|
|
|
|
|
|
case '?':
|
|
/* The last signal which caused a stop. ?
|
|
Success: SAA, where AA is the signal number.
|
|
Failure: void. */
|
|
output_buffer[0] = 'S';
|
|
output_buffer[1] = hex_asc_hi(sigval);
|
|
output_buffer[2] = hex_asc_lo(sigval);
|
|
output_buffer[3] = 0;
|
|
break;
|
|
|
|
case 'D':
|
|
/* Detach from host. D
|
|
Success: OK, and return to the executing thread.
|
|
Failure: will never know */
|
|
putpacket("OK");
|
|
return;
|
|
|
|
case 'k':
|
|
case 'r':
|
|
/* kill request or reset request.
|
|
Success: restart of target.
|
|
Failure: will never know. */
|
|
kill_restart();
|
|
break;
|
|
|
|
case 'C':
|
|
case 'S':
|
|
case '!':
|
|
case 'R':
|
|
case 'd':
|
|
/* Continue with signal sig. Csig;AA..AA
|
|
Step with signal sig. Ssig;AA..AA
|
|
Use the extended remote protocol. !
|
|
Restart the target system. R0
|
|
Toggle debug flag. d
|
|
Search backwards. tAA:PP,MM
|
|
Not supported: E04 */
|
|
|
|
/* FIXME: What's the difference between not supported
|
|
and ignored (below)? */
|
|
gdb_cris_strcpy(output_buffer, error_message[E04]);
|
|
break;
|
|
|
|
default:
|
|
/* The stub should ignore other request and send an empty
|
|
response ($#<checksum>). This way we can extend the protocol and GDB
|
|
can tell whether the stub it is talking to uses the old or the new. */
|
|
output_buffer[0] = 0;
|
|
break;
|
|
}
|
|
putpacket(output_buffer);
|
|
}
|
|
}
|
|
|
|
void
|
|
kgdb_init(void)
|
|
{
|
|
reg_intr_vect_rw_mask intr_mask;
|
|
reg_ser_rw_intr_mask ser_intr_mask;
|
|
|
|
/* Configure the kgdb serial port. */
|
|
#if defined(CONFIG_ETRAX_KGDB_PORT0)
|
|
/* Note: no shortcut registered (not handled by multiple_interrupt).
|
|
See entry.S. */
|
|
set_exception_vector(SER0_INTR_VECT, kgdb_handle_exception);
|
|
/* Enable the ser irq in the global config. */
|
|
intr_mask = REG_RD(intr_vect, regi_irq, rw_mask);
|
|
intr_mask.ser0 = 1;
|
|
REG_WR(intr_vect, regi_irq, rw_mask, intr_mask);
|
|
|
|
ser_intr_mask = REG_RD(ser, regi_ser0, rw_intr_mask);
|
|
ser_intr_mask.dav = regk_ser_yes;
|
|
REG_WR(ser, regi_ser0, rw_intr_mask, ser_intr_mask);
|
|
#elif defined(CONFIG_ETRAX_KGDB_PORT1)
|
|
/* Note: no shortcut registered (not handled by multiple_interrupt).
|
|
See entry.S. */
|
|
set_exception_vector(SER1_INTR_VECT, kgdb_handle_exception);
|
|
/* Enable the ser irq in the global config. */
|
|
intr_mask = REG_RD(intr_vect, regi_irq, rw_mask);
|
|
intr_mask.ser1 = 1;
|
|
REG_WR(intr_vect, regi_irq, rw_mask, intr_mask);
|
|
|
|
ser_intr_mask = REG_RD(ser, regi_ser1, rw_intr_mask);
|
|
ser_intr_mask.dav = regk_ser_yes;
|
|
REG_WR(ser, regi_ser1, rw_intr_mask, ser_intr_mask);
|
|
#elif defined(CONFIG_ETRAX_KGDB_PORT2)
|
|
/* Note: no shortcut registered (not handled by multiple_interrupt).
|
|
See entry.S. */
|
|
set_exception_vector(SER2_INTR_VECT, kgdb_handle_exception);
|
|
/* Enable the ser irq in the global config. */
|
|
intr_mask = REG_RD(intr_vect, regi_irq, rw_mask);
|
|
intr_mask.ser2 = 1;
|
|
REG_WR(intr_vect, regi_irq, rw_mask, intr_mask);
|
|
|
|
ser_intr_mask = REG_RD(ser, regi_ser2, rw_intr_mask);
|
|
ser_intr_mask.dav = regk_ser_yes;
|
|
REG_WR(ser, regi_ser2, rw_intr_mask, ser_intr_mask);
|
|
#elif defined(CONFIG_ETRAX_KGDB_PORT3)
|
|
/* Note: no shortcut registered (not handled by multiple_interrupt).
|
|
See entry.S. */
|
|
set_exception_vector(SER3_INTR_VECT, kgdb_handle_exception);
|
|
/* Enable the ser irq in the global config. */
|
|
intr_mask = REG_RD(intr_vect, regi_irq, rw_mask);
|
|
intr_mask.ser3 = 1;
|
|
REG_WR(intr_vect, regi_irq, rw_mask, intr_mask);
|
|
|
|
ser_intr_mask = REG_RD(ser, regi_ser3, rw_intr_mask);
|
|
ser_intr_mask.dav = regk_ser_yes;
|
|
REG_WR(ser, regi_ser3, rw_intr_mask, ser_intr_mask);
|
|
#endif
|
|
|
|
}
|
|
/* Performs a complete re-start from scratch. */
|
|
static void
|
|
kill_restart(void)
|
|
{
|
|
machine_restart("");
|
|
}
|
|
|
|
/* Use this static breakpoint in the start-up only. */
|
|
|
|
void
|
|
breakpoint(void)
|
|
{
|
|
kgdb_started = 1;
|
|
dynamic_bp = 0; /* This is a static, not a dynamic breakpoint. */
|
|
__asm__ volatile ("break 8"); /* Jump to kgdb_handle_breakpoint. */
|
|
}
|
|
|
|
/****************************** End of file **********************************/
|