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Diffstat (limited to 'arch/sh/kernel/cpu/sh5/unwind.c')
-rw-r--r--arch/sh/kernel/cpu/sh5/unwind.c342
1 files changed, 0 insertions, 342 deletions
diff --git a/arch/sh/kernel/cpu/sh5/unwind.c b/arch/sh/kernel/cpu/sh5/unwind.c
deleted file mode 100644
index 3cb0cd9cea29..000000000000
--- a/arch/sh/kernel/cpu/sh5/unwind.c
+++ /dev/null
@@ -1,342 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * arch/sh/kernel/cpu/sh5/unwind.c
- *
- * Copyright (C) 2004 Paul Mundt
- * Copyright (C) 2004 Richard Curnow
- */
-#include <linux/kallsyms.h>
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/errno.h>
-#include <asm/page.h>
-#include <asm/ptrace.h>
-#include <asm/processor.h>
-#include <asm/io.h>
-#include <asm/unwinder.h>
-#include <asm/stacktrace.h>
-
-static u8 regcache[63];
-
-/*
- * Finding the previous stack frame isn't horribly straightforward as it is
- * on some other platforms. In the sh64 case, we don't have "linked" stack
- * frames, so we need to do a bit of work to determine the previous frame,
- * and in turn, the previous r14/r18 pair.
- *
- * There are generally a few cases which determine where we can find out
- * the r14/r18 values. In the general case, this can be determined by poking
- * around the prologue of the symbol PC is in (note that we absolutely must
- * have frame pointer support as well as the kernel symbol table mapped,
- * otherwise we can't even get this far).
- *
- * In other cases, such as the interrupt/exception path, we can poke around
- * the sp/fp.
- *
- * Notably, this entire approach is somewhat error prone, and in the event
- * that the previous frame cannot be determined, that's all we can do.
- * Either way, this still leaves us with a more correct backtrace then what
- * we would be able to come up with by walking the stack (which is garbage
- * for anything beyond the first frame).
- * -- PFM.
- */
-static int lookup_prev_stack_frame(unsigned long fp, unsigned long pc,
- unsigned long *pprev_fp, unsigned long *pprev_pc,
- struct pt_regs *regs)
-{
- const char *sym;
- char namebuf[128];
- unsigned long offset;
- unsigned long prologue = 0;
- unsigned long fp_displacement = 0;
- unsigned long fp_prev = 0;
- unsigned long offset_r14 = 0, offset_r18 = 0;
- int i, found_prologue_end = 0;
-
- sym = kallsyms_lookup(pc, NULL, &offset, NULL, namebuf);
- if (!sym)
- return -EINVAL;
-
- prologue = pc - offset;
- if (!prologue)
- return -EINVAL;
-
- /* Validate fp, to avoid risk of dereferencing a bad pointer later.
- Assume 128Mb since that's the amount of RAM on a Cayman. Modify
- when there is an SH-5 board with more. */
- if ((fp < (unsigned long) phys_to_virt(__MEMORY_START)) ||
- (fp >= (unsigned long)(phys_to_virt(__MEMORY_START)) + 128*1024*1024) ||
- ((fp & 7) != 0)) {
- return -EINVAL;
- }
-
- /*
- * Depth to walk, depth is completely arbitrary.
- */
- for (i = 0; i < 100; i++, prologue += sizeof(unsigned long)) {
- unsigned long op;
- u8 major, minor;
- u8 src, dest, disp;
-
- op = *(unsigned long *)prologue;
-
- major = (op >> 26) & 0x3f;
- src = (op >> 20) & 0x3f;
- minor = (op >> 16) & 0xf;
- disp = (op >> 10) & 0x3f;
- dest = (op >> 4) & 0x3f;
-
- /*
- * Stack frame creation happens in a number of ways.. in the
- * general case when the stack frame is less than 511 bytes,
- * it's generally created by an addi or addi.l:
- *
- * addi/addi.l r15, -FRAME_SIZE, r15
- *
- * in the event that the frame size is bigger than this, it's
- * typically created using a movi/sub pair as follows:
- *
- * movi FRAME_SIZE, rX
- * sub r15, rX, r15
- */
-
- switch (major) {
- case (0x00 >> 2):
- switch (minor) {
- case 0x8: /* add.l */
- case 0x9: /* add */
- /* Look for r15, r63, r14 */
- if (src == 15 && disp == 63 && dest == 14)
- found_prologue_end = 1;
-
- break;
- case 0xa: /* sub.l */
- case 0xb: /* sub */
- if (src != 15 || dest != 15)
- continue;
-
- fp_displacement -= regcache[disp];
- fp_prev = fp - fp_displacement;
- break;
- }
- break;
- case (0xa8 >> 2): /* st.l */
- if (src != 15)
- continue;
-
- switch (dest) {
- case 14:
- if (offset_r14 || fp_displacement == 0)
- continue;
-
- offset_r14 = (u64)(((((s64)op >> 10) & 0x3ff) << 54) >> 54);
- offset_r14 *= sizeof(unsigned long);
- offset_r14 += fp_displacement;
- break;
- case 18:
- if (offset_r18 || fp_displacement == 0)
- continue;
-
- offset_r18 = (u64)(((((s64)op >> 10) & 0x3ff) << 54) >> 54);
- offset_r18 *= sizeof(unsigned long);
- offset_r18 += fp_displacement;
- break;
- }
-
- break;
- case (0xcc >> 2): /* movi */
- if (dest >= 63) {
- printk(KERN_NOTICE "%s: Invalid dest reg %d "
- "specified in movi handler. Failed "
- "opcode was 0x%lx: ", __func__,
- dest, op);
-
- continue;
- }
-
- /* Sign extend */
- regcache[dest] =
- sign_extend64((((u64)op >> 10) & 0xffff), 9);
- break;
- case (0xd0 >> 2): /* addi */
- case (0xd4 >> 2): /* addi.l */
- /* Look for r15, -FRAME_SIZE, r15 */
- if (src != 15 || dest != 15)
- continue;
-
- /* Sign extended frame size.. */
- fp_displacement +=
- (u64)(((((s64)op >> 10) & 0x3ff) << 54) >> 54);
- fp_prev = fp - fp_displacement;
- break;
- }
-
- if (found_prologue_end && offset_r14 && (offset_r18 || *pprev_pc) && fp_prev)
- break;
- }
-
- if (offset_r14 == 0 || fp_prev == 0) {
- if (!offset_r14)
- pr_debug("Unable to find r14 offset\n");
- if (!fp_prev)
- pr_debug("Unable to find previous fp\n");
-
- return -EINVAL;
- }
-
- /* For innermost leaf function, there might not be a offset_r18 */
- if (!*pprev_pc && (offset_r18 == 0))
- return -EINVAL;
-
- *pprev_fp = *(unsigned long *)(fp_prev + offset_r14);
-
- if (offset_r18)
- *pprev_pc = *(unsigned long *)(fp_prev + offset_r18);
-
- *pprev_pc &= ~1;
-
- return 0;
-}
-
-/*
- * Don't put this on the stack since we'll want to call in to
- * sh64_unwinder_dump() when we're close to underflowing the stack
- * anyway.
- */
-static struct pt_regs here_regs;
-
-extern const char syscall_ret;
-extern const char ret_from_syscall;
-extern const char ret_from_exception;
-extern const char ret_from_irq;
-
-static void sh64_unwind_inner(const struct stacktrace_ops *ops,
- void *data, struct pt_regs *regs);
-
-static inline void unwind_nested(const struct stacktrace_ops *ops, void *data,
- unsigned long pc, unsigned long fp)
-{
- if ((fp >= __MEMORY_START) &&
- ((fp & 7) == 0))
- sh64_unwind_inner(ops, data, (struct pt_regs *)fp);
-}
-
-static void sh64_unwind_inner(const struct stacktrace_ops *ops,
- void *data, struct pt_regs *regs)
-{
- unsigned long pc, fp;
- int ofs = 0;
- int first_pass;
-
- pc = regs->pc & ~1;
- fp = regs->regs[14];
-
- first_pass = 1;
- for (;;) {
- int cond;
- unsigned long next_fp, next_pc;
-
- if (pc == ((unsigned long)&syscall_ret & ~1)) {
- printk("SYSCALL\n");
- unwind_nested(ops, data, pc, fp);
- return;
- }
-
- if (pc == ((unsigned long)&ret_from_syscall & ~1)) {
- printk("SYSCALL (PREEMPTED)\n");
- unwind_nested(ops, data, pc, fp);
- return;
- }
-
- /* In this case, the PC is discovered by lookup_prev_stack_frame but
- it has 4 taken off it to look like the 'caller' */
- if (pc == ((unsigned long)&ret_from_exception & ~1)) {
- printk("EXCEPTION\n");
- unwind_nested(ops, data, pc, fp);
- return;
- }
-
- if (pc == ((unsigned long)&ret_from_irq & ~1)) {
- printk("IRQ\n");
- unwind_nested(ops, data, pc, fp);
- return;
- }
-
- cond = ((pc >= __MEMORY_START) && (fp >= __MEMORY_START) &&
- ((pc & 3) == 0) && ((fp & 7) == 0));
-
- pc -= ofs;
-
- ops->address(data, pc, 1);
-
- if (first_pass) {
- /* If the innermost frame is a leaf function, it's
- * possible that r18 is never saved out to the stack.
- */
- next_pc = regs->regs[18];
- } else {
- next_pc = 0;
- }
-
- if (lookup_prev_stack_frame(fp, pc, &next_fp, &next_pc, regs) == 0) {
- ofs = sizeof(unsigned long);
- pc = next_pc & ~1;
- fp = next_fp;
- } else {
- printk("Unable to lookup previous stack frame\n");
- break;
- }
- first_pass = 0;
- }
-
- printk("\n");
-}
-
-static void sh64_unwinder_dump(struct task_struct *task,
- struct pt_regs *regs,
- unsigned long *sp,
- const struct stacktrace_ops *ops,
- void *data)
-{
- if (!regs) {
- /*
- * Fetch current regs if we have no other saved state to back
- * trace from.
- */
- regs = &here_regs;
-
- __asm__ __volatile__ ("ori r14, 0, %0" : "=r" (regs->regs[14]));
- __asm__ __volatile__ ("ori r15, 0, %0" : "=r" (regs->regs[15]));
- __asm__ __volatile__ ("ori r18, 0, %0" : "=r" (regs->regs[18]));
-
- __asm__ __volatile__ ("gettr tr0, %0" : "=r" (regs->tregs[0]));
- __asm__ __volatile__ ("gettr tr1, %0" : "=r" (regs->tregs[1]));
- __asm__ __volatile__ ("gettr tr2, %0" : "=r" (regs->tregs[2]));
- __asm__ __volatile__ ("gettr tr3, %0" : "=r" (regs->tregs[3]));
- __asm__ __volatile__ ("gettr tr4, %0" : "=r" (regs->tregs[4]));
- __asm__ __volatile__ ("gettr tr5, %0" : "=r" (regs->tregs[5]));
- __asm__ __volatile__ ("gettr tr6, %0" : "=r" (regs->tregs[6]));
- __asm__ __volatile__ ("gettr tr7, %0" : "=r" (regs->tregs[7]));
-
- __asm__ __volatile__ (
- "pta 0f, tr0\n\t"
- "blink tr0, %0\n\t"
- "0: nop"
- : "=r" (regs->pc)
- );
- }
-
- sh64_unwind_inner(ops, data, regs);
-}
-
-static struct unwinder sh64_unwinder = {
- .name = "sh64-unwinder",
- .dump = sh64_unwinder_dump,
- .rating = 150,
-};
-
-static int __init sh64_unwinder_init(void)
-{
- return unwinder_register(&sh64_unwinder);
-}
-early_initcall(sh64_unwinder_init);
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