[PATCH] xtensa: Architecture support for Tensilica Xtensa Part 6

The attached patches provides part 6 of an architecture implementation for the
Tensilica Xtensa CPU series.

Signed-off-by: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 135 insertions, 0 deletions

diff --git a/include/asm-xtensa/ptrace.h b/include/asm-xtensa/ptrace.h
new file mode 100644
index 000000000000..2848a5ff8349
--- /dev/null
+++ b/include/asm-xtensa/ptrace.h
@@ -0,0 +1,135 @@
+/*
+ * include/asm-xtensa/ptrace.h
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2001 - 2005 Tensilica Inc.
+ */
+
+#ifndef _XTENSA_PTRACE_H
+#define _XTENSA_PTRACE_H
+
+#include <xtensa/config/core.h>
+
+/*
+ * Kernel stack
+ *
+ *              +-----------------------+  -------- STACK_SIZE
+ *              |     register file     |  |
+ *              +-----------------------+  |
+ *              |    struct pt_regs     |  |
+ *              +-----------------------+  | ------ PT_REGS_OFFSET
+ * double       :  16 bytes spill area  :  |  ^
+ * excetion     :- - - - - - - - - - - -:  |  |
+ * frame        :    struct pt_regs     :  |  |
+ *              :- - - - - - - - - - - -:  |  |
+ *              |                       |  |  |
+ *              |     memory stack      |  |  |
+ *              |                       |  |  |
+ *              ~                       ~  ~  ~
+ *              ~                       ~  ~  ~
+ *              |                       |  |  |
+ *              |                       |  |  |
+ *              +-----------------------+  |  | --- STACK_BIAS
+ *              |  struct task_struct   |  |  |  ^
+ *  current --> +-----------------------+  |  |  |
+ *              |  struct thread_info   |  |  |  |
+ *              +-----------------------+ --------
+ */
+
+#define KERNEL_STACK_SIZE (2 * PAGE_SIZE)
+
+/*  Offsets for exception_handlers[] (3 x 64-entries x 4-byte tables). */
+
+#define EXC_TABLE_KSTK          0x004   /* Kernel Stack */
+#define EXC_TABLE_DOUBLE_SAVE   0x008   /* Double exception save area for a0 */
+#define EXC_TABLE_FIXUP         0x00c   /* Fixup handler */
+#define EXC_TABLE_PARAM         0x010   /* For passing a parameter to fixup */
+#define EXC_TABLE_SYSCALL_SAVE  0x014   /* For fast syscall handler */
+#define EXC_TABLE_FAST_USER     0x100   /* Fast user exception handler */
+#define EXC_TABLE_FAST_KERNEL   0x200   /* Fast kernel exception handler */
+#define EXC_TABLE_DEFAULT       0x300   /* Default C-Handler */
+#define EXC_TABLE_SIZE          0x400
+
+/* Registers used by strace */
+
+#define REG_A_BASE      0xfc000000
+#define REG_AR_BASE     0x04000000
+#define REG_PC          0x14000000
+#define REG_PS          0x080000e6
+#define REG_WB          0x08000048
+#define REG_WS          0x08000049
+#define REG_LBEG        0x08000000
+#define REG_LEND        0x08000001
+#define REG_LCOUNT      0x08000002
+#define REG_SAR         0x08000003
+#define REG_DEPC        0x080000c0
+#define REG_EXCCAUSE    0x080000e8
+#define REG_EXCVADDR    0x080000ee
+#define SYSCALL_NR      0x1
+
+#define AR_REGNO_TO_A_REGNO(ar, wb) (ar - wb*4) & ~(XCHAL_NUM_AREGS - 1)
+
+/* Other PTRACE_ values defined in <linux/ptrace.h> using values 0-9,16,17,24 */
+
+#define PTRACE_GETREGS            12
+#define PTRACE_SETREGS            13
+#define PTRACE_GETFPREGS          14
+#define PTRACE_SETFPREGS          15
+#define PTRACE_GETFPREGSIZE       18
+
+#ifndef __ASSEMBLY__
+
+/*
+ * This struct defines the way the registers are stored on the
+ * kernel stack during a system call or other kernel entry.
+ */
+struct pt_regs {
+        unsigned long pc;               /*   4 */
+        unsigned long ps;               /*   8 */
+        unsigned long depc;             /*  12 */
+        unsigned long exccause;         /*  16 */
+        unsigned long excvaddr;         /*  20 */
+        unsigned long debugcause;       /*  24 */
+        unsigned long wmask;            /*  28 */
+        unsigned long lbeg;             /*  32 */
+        unsigned long lend;             /*  36 */
+        unsigned long lcount;           /*  40 */
+        unsigned long sar;              /*  44 */
+        unsigned long windowbase;       /*  48 */
+        unsigned long windowstart;      /*  52 */
+        unsigned long syscall;          /*  56 */
+        int reserved[2];                /*  64 */
+
+        /* Make sure the areg field is 16 bytes aligned. */
+        int align[0] __attribute__ ((aligned(16)));
+
+        /* current register frame.
+         * Note: The ESF for kernel exceptions ends after 16 registers!
+         */
+        unsigned long areg[16];         /* 128 (64) */
+};
+
+#ifdef __KERNEL__
+# define xtensa_pt_regs(tsk) ((struct pt_regs*) \
+  (((long)(tsk)->thread_info + KERNEL_STACK_SIZE - (XCHAL_NUM_AREGS-16)*4)) - 1)
+# define user_mode(regs) (((regs)->ps & 0x00000020)!=0)
+# define instruction_pointer(regs) ((regs)->pc)
+extern void show_regs(struct pt_regs *);
+
+# ifndef CONFIG_SMP
+#  define profile_pc(regs) instruction_pointer(regs)
+# endif
+#endif /* __KERNEL__ */
+
+#else   /* __ASSEMBLY__ */
+
+#ifdef __KERNEL__
+# include <asm/offsets.h>
+#define PT_REGS_OFFSET    (KERNEL_STACK_SIZE - PT_USER_SIZE)
+#endif
+
+#endif  /* !__ASSEMBLY__ */
+#endif  /* _XTENSA_PTRACE_H */