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Diffstat (limited to 'ANDROID_3.4.5/arch/microblaze/kernel/unwind.c')
-rw-r--r--ANDROID_3.4.5/arch/microblaze/kernel/unwind.c319
1 files changed, 0 insertions, 319 deletions
diff --git a/ANDROID_3.4.5/arch/microblaze/kernel/unwind.c b/ANDROID_3.4.5/arch/microblaze/kernel/unwind.c
deleted file mode 100644
index 6be4ae3c..00000000
--- a/ANDROID_3.4.5/arch/microblaze/kernel/unwind.c
+++ /dev/null
@@ -1,319 +0,0 @@
-/*
- * Backtrace support for Microblaze
- *
- * Copyright (C) 2010 Digital Design Corporation
- *
- * Based on arch/sh/kernel/cpu/sh5/unwind.c code which is:
- * Copyright (C) 2004 Paul Mundt
- * Copyright (C) 2004 Richard Curnow
- *
- * 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.
- */
-
-/* #define DEBUG 1 */
-#include <linux/kallsyms.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/stacktrace.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <linux/module.h>
-#include <linux/io.h>
-#include <asm/sections.h>
-#include <asm/exceptions.h>
-#include <asm/unwind.h>
-#include <asm/switch_to.h>
-
-struct stack_trace;
-
-/*
- * On Microblaze, finding the previous stack frame is a little tricky.
- * At this writing (3/2010), Microblaze does not support CONFIG_FRAME_POINTERS,
- * and even if it did, gcc (4.1.2) does not store the frame pointer at
- * a consistent offset within each frame. To determine frame size, it is
- * necessary to search for the assembly instruction that creates or reclaims
- * the frame and extract the size from it.
- *
- * Microblaze stores the stack pointer in r1, and creates a frame via
- *
- * addik r1, r1, -FRAME_SIZE
- *
- * The frame is reclaimed via
- *
- * addik r1, r1, FRAME_SIZE
- *
- * Frame creation occurs at or near the top of a function.
- * Depending on the compiler, reclaim may occur at the end, or before
- * a mid-function return.
- *
- * A stack frame is usually not created in a leaf function.
- *
- */
-
-/**
- * get_frame_size - Extract the stack adjustment from an
- * "addik r1, r1, adjust" instruction
- * @instr : Microblaze instruction
- *
- * Return - Number of stack bytes the instruction reserves or reclaims
- */
-inline long get_frame_size(unsigned long instr)
-{
- return abs((s16)(instr & 0xFFFF));
-}
-
-/**
- * find_frame_creation - Search backward to find the instruction that creates
- * the stack frame (hopefully, for the same function the
- * initial PC is in).
- * @pc : Program counter at which to begin the search
- *
- * Return - PC at which stack frame creation occurs
- * NULL if this cannot be found, i.e. a leaf function
- */
-static unsigned long *find_frame_creation(unsigned long *pc)
-{
- int i;
-
- /* NOTE: Distance to search is arbitrary
- * 250 works well for most things,
- * 750 picks up things like tcp_recvmsg(),
- * 1000 needed for fat_fill_super()
- */
- for (i = 0; i < 1000; i++, pc--) {
- unsigned long instr;
- s16 frame_size;
-
- if (!kernel_text_address((unsigned long) pc))
- return NULL;
-
- instr = *pc;
-
- /* addik r1, r1, foo ? */
- if ((instr & 0xFFFF0000) != 0x30210000)
- continue; /* No */
-
- frame_size = get_frame_size(instr);
- if ((frame_size < 8) || (frame_size & 3)) {
- pr_debug(" Invalid frame size %d at 0x%p\n",
- frame_size, pc);
- return NULL;
- }
-
- pr_debug(" Found frame creation at 0x%p, size %d\n", pc,
- frame_size);
- return pc;
- }
-
- return NULL;
-}
-
-/**
- * lookup_prev_stack_frame - Find the stack frame of the previous function.
- * @fp : Frame (stack) pointer for current function
- * @pc : Program counter within current function
- * @leaf_return : r15 value within current function. If the current function
- * is a leaf, this is the caller's return address.
- * @pprev_fp : On exit, set to frame (stack) pointer for previous function
- * @pprev_pc : On exit, set to current function caller's return address
- *
- * Return - 0 on success, -EINVAL if the previous frame cannot be found
- */
-static int lookup_prev_stack_frame(unsigned long fp, unsigned long pc,
- unsigned long leaf_return,
- unsigned long *pprev_fp,
- unsigned long *pprev_pc)
-{
- unsigned long *prologue = NULL;
-
- /* _switch_to is a special leaf function */
- if (pc != (unsigned long) &_switch_to)
- prologue = find_frame_creation((unsigned long *)pc);
-
- if (prologue) {
- long frame_size = get_frame_size(*prologue);
-
- *pprev_fp = fp + frame_size;
- *pprev_pc = *(unsigned long *)fp;
- } else {
- if (!leaf_return)
- return -EINVAL;
- *pprev_pc = leaf_return;
- *pprev_fp = fp;
- }
-
- /* NOTE: don't check kernel_text_address here, to allow display
- * of userland return address
- */
- return (!*pprev_pc || (*pprev_pc & 3)) ? -EINVAL : 0;
-}
-
-static void microblaze_unwind_inner(struct task_struct *task,
- unsigned long pc, unsigned long fp,
- unsigned long leaf_return,
- struct stack_trace *trace);
-
-/**
- * unwind_trap - Unwind through a system trap, that stored previous state
- * on the stack.
- */
-#ifdef CONFIG_MMU
-static inline void unwind_trap(struct task_struct *task, unsigned long pc,
- unsigned long fp, struct stack_trace *trace)
-{
- /* To be implemented */
-}
-#else
-static inline void unwind_trap(struct task_struct *task, unsigned long pc,
- unsigned long fp, struct stack_trace *trace)
-{
- const struct pt_regs *regs = (const struct pt_regs *) fp;
- microblaze_unwind_inner(task, regs->pc, regs->r1, regs->r15, trace);
-}
-#endif
-
-/**
- * microblaze_unwind_inner - Unwind the stack from the specified point
- * @task : Task whose stack we are to unwind (may be NULL)
- * @pc : Program counter from which we start unwinding
- * @fp : Frame (stack) pointer from which we start unwinding
- * @leaf_return : Value of r15 at pc. If the function is a leaf, this is
- * the caller's return address.
- * @trace : Where to store stack backtrace (PC values).
- * NULL == print backtrace to kernel log
- */
-static void microblaze_unwind_inner(struct task_struct *task,
- unsigned long pc, unsigned long fp,
- unsigned long leaf_return,
- struct stack_trace *trace)
-{
- int ofs = 0;
-
- pr_debug(" Unwinding with PC=%p, FP=%p\n", (void *)pc, (void *)fp);
- if (!pc || !fp || (pc & 3) || (fp & 3)) {
- pr_debug(" Invalid state for unwind, aborting\n");
- return;
- }
- for (; pc != 0;) {
- unsigned long next_fp, next_pc = 0;
- unsigned long return_to = pc + 2 * sizeof(unsigned long);
- const struct trap_handler_info *handler =
- &microblaze_trap_handlers;
-
- /* Is previous function the HW exception handler? */
- if ((return_to >= (unsigned long)&_hw_exception_handler)
- &&(return_to < (unsigned long)&ex_handler_unhandled)) {
- /*
- * HW exception handler doesn't save all registers,
- * so we open-code a special case of unwind_trap()
- */
-#ifndef CONFIG_MMU
- const struct pt_regs *regs =
- (const struct pt_regs *) fp;
-#endif
- pr_info("HW EXCEPTION\n");
-#ifndef CONFIG_MMU
- microblaze_unwind_inner(task, regs->r17 - 4,
- fp + EX_HANDLER_STACK_SIZ,
- regs->r15, trace);
-#endif
- return;
- }
-
- /* Is previous function a trap handler? */
- for (; handler->start_addr; ++handler) {
- if ((return_to >= handler->start_addr)
- && (return_to <= handler->end_addr)) {
- if (!trace)
- pr_info("%s\n", handler->trap_name);
- unwind_trap(task, pc, fp, trace);
- return;
- }
- }
- pc -= ofs;
-
- if (trace) {
-#ifdef CONFIG_STACKTRACE
- if (trace->skip > 0)
- trace->skip--;
- else
- trace->entries[trace->nr_entries++] = pc;
-
- if (trace->nr_entries >= trace->max_entries)
- break;
-#endif
- } else {
- /* Have we reached userland? */
- if (unlikely(pc == task_pt_regs(task)->pc)) {
- pr_info("[<%p>] PID %lu [%s]\n",
- (void *) pc,
- (unsigned long) task->pid,
- task->comm);
- break;
- } else
- print_ip_sym(pc);
- }
-
- /* Stop when we reach anything not part of the kernel */
- if (!kernel_text_address(pc))
- break;
-
- if (lookup_prev_stack_frame(fp, pc, leaf_return, &next_fp,
- &next_pc) == 0) {
- ofs = sizeof(unsigned long);
- pc = next_pc & ~3;
- fp = next_fp;
- leaf_return = 0;
- } else {
- pr_debug(" Failed to find previous stack frame\n");
- break;
- }
-
- pr_debug(" Next PC=%p, next FP=%p\n",
- (void *)next_pc, (void *)next_fp);
- }
-}
-
-/**
- * microblaze_unwind - Stack unwinder for Microblaze (external entry point)
- * @task : Task whose stack we are to unwind (NULL == current)
- * @trace : Where to store stack backtrace (PC values).
- * NULL == print backtrace to kernel log
- */
-void microblaze_unwind(struct task_struct *task, struct stack_trace *trace)
-{
- if (task) {
- if (task == current) {
- const struct pt_regs *regs = task_pt_regs(task);
- microblaze_unwind_inner(task, regs->pc, regs->r1,
- regs->r15, trace);
- } else {
- struct thread_info *thread_info =
- (struct thread_info *)(task->stack);
- const struct cpu_context *cpu_context =
- &thread_info->cpu_context;
-
- microblaze_unwind_inner(task,
- (unsigned long) &_switch_to,
- cpu_context->r1,
- cpu_context->r15, trace);
- }
- } else {
- unsigned long pc, fp;
-
- __asm__ __volatile__ ("or %0, r1, r0" : "=r" (fp));
-
- __asm__ __volatile__ (
- "brlid %0, 0f;"
- "nop;"
- "0:"
- : "=r" (pc)
- );
-
- /* Since we are not a leaf function, use leaf_return = 0 */
- microblaze_unwind_inner(current, pc, fp, 0, trace);
- }
-}
-
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