patch-2.4.22 linux-2.4.22/arch/sh64/kernel/traps.c

• Lines: 305
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/arch/sh64/kernel/traps.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/arch/sh64/kernel/traps.c linux-2.4.22/arch/sh64/kernel/traps.c
@@ -0,0 +1,304 @@
+/*
+ * 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.
+ *
+ * arch/sh64/kernel/traps.c
+ *
+ * Copyright (C) 2000, 2001  Paolo Alberelli
+ * Copyright (C) 2003  Paul Mundt
+ *
+ */
+
+/*
+ * 'Traps.c' handles hardware traps and faults after we have saved some
+ * state in 'entry.S'.
+ */
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/ptrace.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/spinlock.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/atomic.h>
+#include <asm/processor.h>
+
+#undef DEBUG_EXCEPTION
+#ifdef DEBUG_EXCEPTION
+/* implemented in ../lib/dbg.c */
+extern void show_excp_regs(char *fname, int trapnr, int signr,
+			   struct pt_regs *regs);
+#else
+#define show_excp_regs(a, b, c, d)
+#endif
+
+#define DO_ERROR(trapnr, signr, str, name, tsk) \
+asmlinkage void do_##name(unsigned long error_code, struct pt_regs *regs) \
+{ \
+	show_excp_regs(__FUNCTION__, trapnr, signr, regs); \
+	tsk->thread.error_code = error_code; \
+	tsk->thread.trap_no = trapnr; \
+	if (user_mode(regs)) force_sig(signr, tsk); \
+	die_if_no_fixup(str,regs,error_code); \
+}
+
+spinlock_t die_lock;
+
+void die(const char * str, struct pt_regs * regs, long err)
+{
+	console_verbose();
+	spin_lock_irq(&die_lock);
+	printk("%s: %lx\n", str, (err & 0xffffff));
+	show_regs(regs);
+	spin_unlock_irq(&die_lock);
+	do_exit(SIGSEGV);
+}
+
+static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
+{
+	if (!user_mode(regs))
+		die(str, regs, err);
+}
+
+static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
+{
+	if (!user_mode(regs))
+	{
+		unsigned long fixup;
+		fixup = search_exception_table(regs->pc);
+		if (fixup) {
+			regs->pc = fixup;
+			return;
+		}
+		die(str, regs, err);
+	}
+}
+
+DO_ERROR( 7, SIGSEGV, "address error (load)", address_error_load, current)
+DO_ERROR( 8, SIGSEGV, "address error (store)", address_error_store, current)
+DO_ERROR(13, SIGILL,  "illegal slot instruction", illegal_slot_inst, current)
+DO_ERROR(87, SIGSEGV, "address error (exec)", address_error_exec, current)
+
+#if defined(CONFIG_SH64_ID2815_WORKAROUND)
+
+#define OPCODE_INVALID      0
+#define OPCODE_USER_VALID   1
+#define OPCODE_PRIV_VALID   2
+
+/* getcon/putcon - requires checking which control register is referenced. */
+#define OPCODE_CTRL_REG     3
+
+/* Table of valid opcodes for SHmedia mode.
+   Form a 10-bit value by concatenating the major/minor opcodes i.e.
+   opcode[31:26,20:16].  The 6 MSBs of this value index into the following
+   array.  The 4 LSBs select the bit-pair in the entry (bits 1:0 correspond to
+   LSBs==4'b0000 etc). */
+static unsigned long shmedia_opcode_table[64] = {
+	0x55554044,0x54445055,0x15141514,0x14541414,0x00000000,0x10001000,0x01110055,0x04050015,
+	0x00000444,0xc0000000,0x44545515,0x40405555,0x55550015,0x10005555,0x55555505,0x04050000,
+	0x00000555,0x00000404,0x00040445,0x15151414,0x00000000,0x00000000,0x00000000,0x00000000,
+	0x00000055,0x40404444,0x00000404,0xc0009495,0x00000000,0x00000000,0x00000000,0x00000000,
+	0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
+	0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
+	0x80005050,0x04005055,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
+	0x81055554,0x00000404,0x55555555,0x55555555,0x00000000,0x00000000,0x00000000,0x00000000
+};
+
+void do_reserved_inst(unsigned long error_code, struct pt_regs *regs)
+{
+	/* Workaround SH5-101 cut2 silicon defect #2815 :
+	   in some situations, inter-mode branches from SHcompact -> SHmedia
+	   which should take ITLBMISS or EXECPROT exceptions at the target
+	   falsely take RESINST at the target instead. */
+
+	unsigned long opcode;
+	unsigned long pc, aligned_pc;
+	int get_user_error;
+	int trapnr = 12;
+	int signr = SIGILL;
+	char *exception_name = "reserved_instruction";
+
+	pc = regs->pc;
+	if ((pc & 3) == 1) {
+		/* SHmedia : check for defect.  This requires executable vmas
+		   to be readable too. */
+		aligned_pc = pc & ~3;
+		if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
+			get_user_error = -EFAULT;
+		} else {
+			get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
+		}
+		if (get_user_error >= 0) {
+			unsigned long index, shift;
+			unsigned long major, minor, combined;
+			unsigned long reserved_field;
+			reserved_field = opcode & 0xf; /* These bits are currently reserved as zero in all valid opcodes */
+			major = (opcode >> 26) & 0x3f;
+			minor = (opcode >> 16) & 0xf;
+			combined = (major << 4) | minor;
+			index = major;
+			shift = minor << 1;
+			if (reserved_field == 0) {
+				int opcode_state = (shmedia_opcode_table[index] >> shift) & 0x3;
+				switch (opcode_state) {
+					case OPCODE_INVALID:
+						/* Trap. */
+						break;
+					case OPCODE_USER_VALID:
+						/* Restart the instruction : the branch to the instruction will now be from an RTE
+						   not from SHcompact so the silicon defect won't be triggered. */
+						return;
+					case OPCODE_PRIV_VALID:
+						if (!user_mode(regs)) {
+							/* Should only ever get here if a module has
+							   SHcompact code inside it.  If so, the same fix up is needed. */
+							return; /* same reason */
+						}
+						/* Otherwise, user mode trying to execute a privileged instruction - 
+						   fall through to trap. */
+						break;
+					case OPCODE_CTRL_REG:
+						/* If in privileged mode, return as above. */
+						if (!user_mode(regs)) return; 
+						/* In user mode ... */
+						if (combined == 0x9f) { /* GETCON */
+							unsigned long regno = (opcode >> 20) & 0x3f;
+							if (regno >= 62) {
+								return;
+							}
+							/* Otherwise, reserved or privileged control register, => trap */
+						} else if (combined == 0x1bf) { /* PUTCON */
+							unsigned long regno = (opcode >> 4) & 0x3f;
+							if (regno >= 62) {
+								return;
+							}
+							/* Otherwise, reserved or privileged control register, => trap */
+						} else {
+							/* Trap */
+						}
+						break;
+					default:
+						/* Fall through to trap. */
+						break;
+				}
+			}
+			/* fall through to normal resinst processing */
+		} else {
+			/* Error trying to read opcode.  This typically means a
+			   real fault, not a RESINST any more.  So change the
+			   codes. */
+			trapnr = 87;
+			exception_name = "address error (exec)";
+			signr = SIGSEGV;
+		}
+	}
+
+	show_excp_regs("do_reserved_inst", trapnr, signr, regs);
+	current->thread.error_code = error_code;
+	current->thread.trap_no = trapnr;
+	if (user_mode(regs)) force_sig(signr, current);
+	die_if_no_fixup(exception_name, regs, error_code);
+}
+
+#else /* CONFIG_SH64_ID2815_WORKAROUND */
+
+/* If the workaround isn't needed, this is just a straightforward reserved
+   instruction */
+DO_ERROR(12, SIGILL,  "reserved instruction", reserved_inst, current)
+
+#endif /* CONFIG_SH64_ID2815_WORKAROUND */
+
+
+#include <asm/system.h>
+
+/* Called with interrupts disabled */
+asmlinkage void do_exception_error(unsigned long ex, struct pt_regs *regs)
+{
+	PLS();
+	show_excp_regs(__FUNCTION__, -1, -1, regs);
+	die_if_kernel("exception", regs, ex);
+}
+
+int do_unknown_trapa(unsigned long scId, struct pt_regs *regs)
+{	
+	/* Syscall debug */
+        printk("System call ID error: [0x1#args:8 #syscall:16  0x%lx]\n", scId);
+
+	die_if_kernel("unknown trapa", regs, scId);
+
+	return -ENOSYS;
+}
+
+void show_task(unsigned long *sp)
+{
+	unsigned long module_start, module_end;
+	unsigned long kernel_start, kernel_end;
+	unsigned long *stack;
+	extern int _text, _etext;
+	int i = 1;
+
+	kernel_start = (unsigned long)&_text;
+	kernel_end   = (unsigned long)&_etext;
+
+	module_start = VMALLOC_START;
+	module_end   = VMALLOC_END;
+
+	if (!sp) {
+		/*
+		 * If we haven't specified a sane sp, fetch it..
+		 */
+		__asm__ __volatile__ (
+			"or	r15, r63, %0\n\t"
+			"getcon " __c17 ", %1\n\t"
+			: "=r" (module_start),
+			  "=r" (module_end)
+		);
+
+		sp = (unsigned long *)module_start;
+	}
+
+	stack = sp;
+
+	printk("\nCall Trace: ");
+
+	while ((unsigned long)stack & (PAGE_SIZE - 1)) {
+		unsigned long addr = *stack++;
+
+		if ((addr >= kernel_start && addr < kernel_end) ||
+		    (addr >= module_start && addr < module_end)) {
+			/* 
+			 * Do a bit of formatting here.. on an 80 column
+			 * display, 6 entries is the most we can deal with
+			 * per-line, since each address will take up 13 spaces.
+			 */
+			if (i && ((i % 6) == 0))
+				printk("\n       ");
+
+			printk("[<%08lx>] ", addr);
+			i++;
+		}
+	}
+
+	printk("\n");
+}
+
+void show_trace_task(struct task_struct *tsk)
+{
+	show_task((unsigned long *)tsk->thread.sp);
+}
+
+void dump_stack(void)
+{
+	show_task(NULL);
+}
+