-obj-y := entry.o
+obj-y := entry.o switchto.o
+
+obj-$(CONFIG_KALLSYMS) += unwind.o
--- /dev/null
+/*
+ * arch/sh64/kernel/switchto.S
+ *
+ * sh64 context switch
+ *
+ * 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.
+*/
+
+ .section .text..SHmedia32,"ax"
+ .little
+
+ .balign 32
+
+ .type sh64_switch_to,@function
+ .global sh64_switch_to
+ .global __sh64_switch_to_end
+sh64_switch_to:
+
+/* Incoming args
+ r2 - prev
+ r3 - &prev->thread
+ r4 - next
+ r5 - &next->thread
+
+ Outgoing results
+ r2 - last (=prev) : this just stays in r2 throughout
+
+ Want to create a full (struct pt_regs) on the stack to allow backtracing
+ functions to work. However, we only need to populate the callee-save
+ register slots in this structure; since we're a function our ancestors must
+ have themselves preserved all caller saved state in the stack. This saves
+ some wasted effort since we won't need to look at the values.
+
+ In particular, all caller-save registers are immediately available for
+ scratch use.
+
+*/
+
+#define FRAME_SIZE (76*8 + 8)
+
+ movi FRAME_SIZE, r0
+ sub.l r15, r0, r15
+ ! Do normal-style register save to support backtrace
+
+ st.l r15, 0, r18 ! save link reg
+ st.l r15, 4, r14 ! save fp
+ add.l r15, r63, r14 ! setup frame pointer
+
+ ! hopefully this looks normal to the backtrace now.
+
+ addi.l r15, 8, r1 ! base of pt_regs
+ addi.l r1, 24, r0 ! base of pt_regs.regs
+ addi.l r0, (63*8), r8 ! base of pt_regs.trregs
+
+ /* Note : to be fixed?
+ struct pt_regs is really designed for holding the state on entry
+ to an exception, i.e. pc,sr,regs etc. However, for the context
+ switch state, some of this is not required. But the unwinder takes
+ struct pt_regs * as an arg so we have to build this structure
+ to allow unwinding switched tasks in show_state() */
+
+ st.q r0, ( 9*8), r9
+ st.q r0, (10*8), r10
+ st.q r0, (11*8), r11
+ st.q r0, (12*8), r12
+ st.q r0, (13*8), r13
+ st.q r0, (14*8), r14 ! for unwind, want to look as though we took a trap at
+ ! the point where the process is left in suspended animation, i.e. current
+ ! fp here, not the saved one.
+ st.q r0, (16*8), r16
+
+ st.q r0, (24*8), r24
+ st.q r0, (25*8), r25
+ st.q r0, (26*8), r26
+ st.q r0, (27*8), r27
+ st.q r0, (28*8), r28
+ st.q r0, (29*8), r29
+ st.q r0, (30*8), r30
+ st.q r0, (31*8), r31
+ st.q r0, (32*8), r32
+ st.q r0, (33*8), r33
+ st.q r0, (34*8), r34
+ st.q r0, (35*8), r35
+
+ st.q r0, (44*8), r44
+ st.q r0, (45*8), r45
+ st.q r0, (46*8), r46
+ st.q r0, (47*8), r47
+ st.q r0, (48*8), r48
+ st.q r0, (49*8), r49
+ st.q r0, (50*8), r50
+ st.q r0, (51*8), r51
+ st.q r0, (52*8), r52
+ st.q r0, (53*8), r53
+ st.q r0, (54*8), r54
+ st.q r0, (55*8), r55
+ st.q r0, (56*8), r56
+ st.q r0, (57*8), r57
+ st.q r0, (58*8), r58
+ st.q r0, (59*8), r59
+
+ ! do this early as pta->gettr has no pipeline forwarding (=> 5 cycle latency)
+ ! Use a local label to avoid creating a symbol that will confuse the !
+ ! backtrace
+ pta .Lsave_pc, tr0
+
+ gettr tr5, r45
+ gettr tr6, r46
+ gettr tr7, r47
+ st.q r8, (5*8), r45
+ st.q r8, (6*8), r46
+ st.q r8, (7*8), r47
+
+ ! Now switch context
+ gettr tr0, r9
+ st.l r3, 0, r15 ! prev->thread.sp
+ st.l r3, 8, r1 ! prev->thread.kregs
+ st.l r3, 4, r9 ! prev->thread.pc
+ st.q r1, 0, r9 ! save prev->thread.pc into pt_regs->pc
+
+ ! Load PC for next task (init value or save_pc later)
+ ld.l r5, 4, r18 ! next->thread.pc
+ ! Switch stacks
+ ld.l r5, 0, r15 ! next->thread.sp
+ ptabs r18, tr0
+
+ ! Update current
+ ld.l r4, 4, r9 ! next->thread_info (2nd element of next task_struct)
+ putcon r9, kcr0 ! current = next->thread_info
+
+ ! go to save_pc for a reschedule, or the initial thread.pc for a new process
+ blink tr0, r63
+
+ ! Restore (when we come back to a previously saved task)
+.Lsave_pc:
+ addi.l r15, 32, r0 ! r0 = next's regs
+ addi.l r0, (63*8), r8 ! r8 = next's tr_regs
+
+ ld.q r8, (5*8), r45
+ ld.q r8, (6*8), r46
+ ld.q r8, (7*8), r47
+ ptabs r45, tr5
+ ptabs r46, tr6
+ ptabs r47, tr7
+
+ ld.q r0, ( 9*8), r9
+ ld.q r0, (10*8), r10
+ ld.q r0, (11*8), r11
+ ld.q r0, (12*8), r12
+ ld.q r0, (13*8), r13
+ ld.q r0, (14*8), r14
+ ld.q r0, (16*8), r16
+
+ ld.q r0, (24*8), r24
+ ld.q r0, (25*8), r25
+ ld.q r0, (26*8), r26
+ ld.q r0, (27*8), r27
+ ld.q r0, (28*8), r28
+ ld.q r0, (29*8), r29
+ ld.q r0, (30*8), r30
+ ld.q r0, (31*8), r31
+ ld.q r0, (32*8), r32
+ ld.q r0, (33*8), r33
+ ld.q r0, (34*8), r34
+ ld.q r0, (35*8), r35
+
+ ld.q r0, (44*8), r44
+ ld.q r0, (45*8), r45
+ ld.q r0, (46*8), r46
+ ld.q r0, (47*8), r47
+ ld.q r0, (48*8), r48
+ ld.q r0, (49*8), r49
+ ld.q r0, (50*8), r50
+ ld.q r0, (51*8), r51
+ ld.q r0, (52*8), r52
+ ld.q r0, (53*8), r53
+ ld.q r0, (54*8), r54
+ ld.q r0, (55*8), r55
+ ld.q r0, (56*8), r56
+ ld.q r0, (57*8), r57
+ ld.q r0, (58*8), r58
+ ld.q r0, (59*8), r59
+
+ ! epilogue
+ ld.l r15, 0, r18
+ ld.l r15, 4, r14
+ ptabs r18, tr0
+ movi FRAME_SIZE, r0
+ add r15, r0, r15
+ blink tr0, r63
+__sh64_switch_to_end:
+.LFE1:
+ .size sh64_switch_to,.LFE1-sh64_switch_to
+
--- /dev/null
+/*
+ * arch/sh64/kernel/unwind.c
+ *
+ * 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.
+ */
+#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>
+
+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: ", __FUNCTION__,
+ dest, op);
+
+ continue;
+ }
+
+ /* Sign extend */
+ regcache[dest] =
+ ((((s64)(u64)op >> 10) & 0xffff) << 54) >> 54;
+ 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 sh64_unwind
+ * 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(struct pt_regs *regs);
+
+static void unwind_nested (unsigned long pc, unsigned long fp)
+{
+ if ((fp >= __MEMORY_START) &&
+ ((fp & 7) == 0)) {
+ sh64_unwind_inner((struct pt_regs *) fp);
+ }
+}
+
+static void sh64_unwind_inner(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(pc,fp);
+ return;
+ }
+
+ if (pc == ((unsigned long) &ret_from_syscall & ~1)) {
+ printk("SYSCALL (PREEMPTED)\n");
+ unwind_nested(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(pc,fp);
+ return;
+ }
+
+ if (pc == ((unsigned long) &ret_from_irq & ~1)) {
+ printk("IRQ\n");
+ unwind_nested(pc,fp);
+ return;
+ }
+
+ cond = ((pc >= __MEMORY_START) && (fp >= __MEMORY_START) &&
+ ((pc & 3) == 0) && ((fp & 7) == 0));
+
+ pc -= ofs;
+
+ printk("[<%08lx>] ", pc);
+ print_symbol("%s\n", pc);
+
+ 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");
+
+}
+
+void sh64_unwind(struct pt_regs *regs)
+{
+ 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)
+ );
+ }
+
+ printk("\nCall Trace:\n");
+ sh64_unwind_inner(regs);
+}
+
+++ /dev/null
-/*
- * arch/sh64/kernel/switchto.S
- *
- * sh64 context switch
- *
- * 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.
-*/
-
- .section .text..SHmedia32,"ax"
- .little
-
- .balign 32
-
- .type sh64_switch_to,@function
- .global sh64_switch_to
- .global __sh64_switch_to_end
-sh64_switch_to:
-
-/* Incoming args
- r2 - prev
- r3 - &prev->thread
- r4 - next
- r5 - &next->thread
-
- Outgoing results
- r2 - last (=prev) : this just stays in r2 throughout
-
- Want to create a full (struct pt_regs) on the stack to allow backtracing
- functions to work. However, we only need to populate the callee-save
- register slots in this structure; since we're a function our ancestors must
- have themselves preserved all caller saved state in the stack. This saves
- some wasted effort since we won't need to look at the values.
-
- In particular, all caller-save registers are immediately available for
- scratch use.
-
-*/
-
-#define FRAME_SIZE (76*8 + 8)
-
- movi FRAME_SIZE, r0
- sub.l r15, r0, r15
- ! Do normal-style register save to support backtrace
-
- st.l r15, 0, r18 ! save link reg
- st.l r15, 4, r14 ! save fp
- add.l r15, r63, r14 ! setup frame pointer
-
- ! hopefully this looks normal to the backtrace now.
-
- addi.l r15, 8, r1 ! base of pt_regs
- addi.l r1, 24, r0 ! base of pt_regs.regs
- addi.l r0, (63*8), r8 ! base of pt_regs.trregs
-
- /* Note : to be fixed?
- struct pt_regs is really designed for holding the state on entry
- to an exception, i.e. pc,sr,regs etc. However, for the context
- switch state, some of this is not required. But the unwinder takes
- struct pt_regs * as an arg so we have to build this structure
- to allow unwinding switched tasks in show_state() */
-
- st.q r0, ( 9*8), r9
- st.q r0, (10*8), r10
- st.q r0, (11*8), r11
- st.q r0, (12*8), r12
- st.q r0, (13*8), r13
- st.q r0, (14*8), r14 ! for unwind, want to look as though we took a trap at
- ! the point where the process is left in suspended animation, i.e. current
- ! fp here, not the saved one.
- st.q r0, (16*8), r16
-
- st.q r0, (24*8), r24
- st.q r0, (25*8), r25
- st.q r0, (26*8), r26
- st.q r0, (27*8), r27
- st.q r0, (28*8), r28
- st.q r0, (29*8), r29
- st.q r0, (30*8), r30
- st.q r0, (31*8), r31
- st.q r0, (32*8), r32
- st.q r0, (33*8), r33
- st.q r0, (34*8), r34
- st.q r0, (35*8), r35
-
- st.q r0, (44*8), r44
- st.q r0, (45*8), r45
- st.q r0, (46*8), r46
- st.q r0, (47*8), r47
- st.q r0, (48*8), r48
- st.q r0, (49*8), r49
- st.q r0, (50*8), r50
- st.q r0, (51*8), r51
- st.q r0, (52*8), r52
- st.q r0, (53*8), r53
- st.q r0, (54*8), r54
- st.q r0, (55*8), r55
- st.q r0, (56*8), r56
- st.q r0, (57*8), r57
- st.q r0, (58*8), r58
- st.q r0, (59*8), r59
-
- ! do this early as pta->gettr has no pipeline forwarding (=> 5 cycle latency)
- ! Use a local label to avoid creating a symbol that will confuse the !
- ! backtrace
- pta .Lsave_pc, tr0
-
- gettr tr5, r45
- gettr tr6, r46
- gettr tr7, r47
- st.q r8, (5*8), r45
- st.q r8, (6*8), r46
- st.q r8, (7*8), r47
-
- ! Now switch context
- gettr tr0, r9
- st.l r3, 0, r15 ! prev->thread.sp
- st.l r3, 8, r1 ! prev->thread.kregs
- st.l r3, 4, r9 ! prev->thread.pc
- st.q r1, 0, r9 ! save prev->thread.pc into pt_regs->pc
-
- ! Load PC for next task (init value or save_pc later)
- ld.l r5, 4, r18 ! next->thread.pc
- ! Switch stacks
- ld.l r5, 0, r15 ! next->thread.sp
- ptabs r18, tr0
-
- ! Update current
- ld.l r4, 4, r9 ! next->thread_info (2nd element of next task_struct)
- putcon r9, kcr0 ! current = next->thread_info
-
- ! go to save_pc for a reschedule, or the initial thread.pc for a new process
- blink tr0, r63
-
- ! Restore (when we come back to a previously saved task)
-.Lsave_pc:
- addi.l r15, 32, r0 ! r0 = next's regs
- addi.l r0, (63*8), r8 ! r8 = next's tr_regs
-
- ld.q r8, (5*8), r45
- ld.q r8, (6*8), r46
- ld.q r8, (7*8), r47
- ptabs r45, tr5
- ptabs r46, tr6
- ptabs r47, tr7
-
- ld.q r0, ( 9*8), r9
- ld.q r0, (10*8), r10
- ld.q r0, (11*8), r11
- ld.q r0, (12*8), r12
- ld.q r0, (13*8), r13
- ld.q r0, (14*8), r14
- ld.q r0, (16*8), r16
-
- ld.q r0, (24*8), r24
- ld.q r0, (25*8), r25
- ld.q r0, (26*8), r26
- ld.q r0, (27*8), r27
- ld.q r0, (28*8), r28
- ld.q r0, (29*8), r29
- ld.q r0, (30*8), r30
- ld.q r0, (31*8), r31
- ld.q r0, (32*8), r32
- ld.q r0, (33*8), r33
- ld.q r0, (34*8), r34
- ld.q r0, (35*8), r35
-
- ld.q r0, (44*8), r44
- ld.q r0, (45*8), r45
- ld.q r0, (46*8), r46
- ld.q r0, (47*8), r47
- ld.q r0, (48*8), r48
- ld.q r0, (49*8), r49
- ld.q r0, (50*8), r50
- ld.q r0, (51*8), r51
- ld.q r0, (52*8), r52
- ld.q r0, (53*8), r53
- ld.q r0, (54*8), r54
- ld.q r0, (55*8), r55
- ld.q r0, (56*8), r56
- ld.q r0, (57*8), r57
- ld.q r0, (58*8), r58
- ld.q r0, (59*8), r59
-
- ! epilogue
- ld.l r15, 0, r18
- ld.l r15, 4, r14
- ptabs r18, tr0
- movi FRAME_SIZE, r0
- add r15, r0, r15
- blink tr0, r63
-__sh64_switch_to_end:
-.LFE1:
- .size sh64_switch_to,.LFE1-sh64_switch_to
-
+++ /dev/null
-/*
- * arch/sh64/kernel/unwind.c
- *
- * 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.
- */
-#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>
-
-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: ", __FUNCTION__,
- dest, op);
-
- continue;
- }
-
- /* Sign extend */
- regcache[dest] =
- ((((s64)(u64)op >> 10) & 0xffff) << 54) >> 54;
- 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 sh64_unwind
- * 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(struct pt_regs *regs);
-
-static void unwind_nested (unsigned long pc, unsigned long fp)
-{
- if ((fp >= __MEMORY_START) &&
- ((fp & 7) == 0)) {
- sh64_unwind_inner((struct pt_regs *) fp);
- }
-}
-
-static void sh64_unwind_inner(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(pc,fp);
- return;
- }
-
- if (pc == ((unsigned long) &ret_from_syscall & ~1)) {
- printk("SYSCALL (PREEMPTED)\n");
- unwind_nested(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(pc,fp);
- return;
- }
-
- if (pc == ((unsigned long) &ret_from_irq & ~1)) {
- printk("IRQ\n");
- unwind_nested(pc,fp);
- return;
- }
-
- cond = ((pc >= __MEMORY_START) && (fp >= __MEMORY_START) &&
- ((pc & 3) == 0) && ((fp & 7) == 0));
-
- pc -= ofs;
-
- printk("[<%08lx>] ", pc);
- print_symbol("%s\n", pc);
-
- 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");
-
-}
-
-void sh64_unwind(struct pt_regs *regs)
-{
- 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)
- );
- }
-
- printk("\nCall Trace:\n");
- sh64_unwind_inner(regs);
-}
-
projects / openwrt / staging / blogic.git / commitdiff