Commit f21a79ca authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: clean up exception handling structure 



Instead of using flat array of longs use normal C structure and generate
EXC_TABLE_* constants in the asm-offsets.c

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent c130d3be

arch/xtensa/include/asm/ptrace.h

+0 −12
Original line number Diff line number Diff line
@@ -39,18 +39,6 @@ 
 *		+-----------------------+ --------

 */



/*  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



#ifndef __ASSEMBLY__



#include <asm/coprocessor.h>

arch/xtensa/include/asm/regs.h

+1 −0
Original line number Diff line number Diff line
@@ -76,6 +76,7 @@ 
#define EXCCAUSE_COPROCESSOR5_DISABLED		37

#define EXCCAUSE_COPROCESSOR6_DISABLED		38

#define EXCCAUSE_COPROCESSOR7_DISABLED		39

#define EXCCAUSE_N				64



/*  PS register fields.  */

arch/xtensa/include/asm/traps.h

+23 −0
Original line number Diff line number Diff line
@@ -12,6 +12,29 @@ 


#include <asm/ptrace.h>



/*

 * Per-CPU exception handling data structure.

 * EXCSAVE1 points to it.

 */

struct exc_table {

	/* Kernel Stack */

	void *kstk;

	/* Double exception save area for a0 */

	unsigned long double_save;

	/* Fixup handler */

	void *fixup;

	/* For passing a parameter to fixup */

	void *fixup_param;

	/* For fast syscall handler */

	unsigned long syscall_save;

	/* Fast user exception handlers */

	void *fast_user_handler[EXCCAUSE_N];

	/* Fast kernel exception handlers */

	void *fast_kernel_handler[EXCCAUSE_N];

	/* Default C-Handlers */

	void *default_handler[EXCCAUSE_N];

};



/*

 * handler must be either of the following:

 *  void (*)(struct pt_regs *regs);

arch/xtensa/kernel/asm-offsets.c

+13 −0
Original line number Diff line number Diff line
@@ -132,5 +132,18 @@ int main(void) 
	       offsetof(struct debug_table, icount_level_save));

#endif



	/* struct exc_table */

	DEFINE(EXC_TABLE_KSTK, offsetof(struct exc_table, kstk));

	DEFINE(EXC_TABLE_DOUBLE_SAVE, offsetof(struct exc_table, double_save));

	DEFINE(EXC_TABLE_FIXUP, offsetof(struct exc_table, fixup));

	DEFINE(EXC_TABLE_PARAM, offsetof(struct exc_table, fixup_param));

	DEFINE(EXC_TABLE_SYSCALL_SAVE,

	       offsetof(struct exc_table, syscall_save));

	DEFINE(EXC_TABLE_FAST_USER,

	       offsetof(struct exc_table, fast_user_handler));

	DEFINE(EXC_TABLE_FAST_KERNEL,

	       offsetof(struct exc_table, fast_kernel_handler));

	DEFINE(EXC_TABLE_DEFAULT, offsetof(struct exc_table, default_handler));



	return 0;

}

arch/xtensa/kernel/traps.c

+19 −20
Original line number Diff line number Diff line
@@ -159,8 +159,7 @@ COPROCESSOR(7), 
 * 2. it is a temporary memory buffer for the exception handlers.

 */



DEFINE_PER_CPU(unsigned long, exc_table[EXC_TABLE_SIZE/4]);



DEFINE_PER_CPU(struct exc_table, exc_table);

DEFINE_PER_CPU(struct debug_table, debug_table);



void die(const char*, struct pt_regs*, long);
@@ -368,28 +367,28 @@ do_debug(struct pt_regs *regs) 
}





static void set_handler(int idx, void *handler)

{

	unsigned int cpu;



	for_each_possible_cpu(cpu)

		per_cpu(exc_table, cpu)[idx] = (unsigned long)handler;

}

#define set_handler(type, cause, handler)				\

	do {								\

		unsigned int cpu;					\

									\

		for_each_possible_cpu(cpu)				\

			per_cpu(exc_table, cpu).type[cause] = (handler);\

	} while (0)



/* Set exception C handler - for temporary use when probing exceptions */



void * __init trap_set_handler(int cause, void *handler)

{

	void *previous = (void *)per_cpu(exc_table, 0)[

		EXC_TABLE_DEFAULT / 4 + cause];

	set_handler(EXC_TABLE_DEFAULT / 4 + cause, handler);

	void *previous = per_cpu(exc_table, 0).default_handler[cause];



	set_handler(default_handler, cause, handler);

	return previous;

}





static void trap_init_excsave(void)

{

	unsigned long excsave1 = (unsigned long)this_cpu_ptr(exc_table);

	unsigned long excsave1 = (unsigned long)this_cpu_ptr(&exc_table);

	__asm__ __volatile__("wsr  %0, excsave1\n" : : "a" (excsave1));

}
@@ -421,10 +420,10 @@ void __init trap_init(void) 


	/* Setup default vectors. */



	for(i = 0; i < 64; i++) {

		set_handler(EXC_TABLE_FAST_USER/4   + i, user_exception);

		set_handler(EXC_TABLE_FAST_KERNEL/4 + i, kernel_exception);

		set_handler(EXC_TABLE_DEFAULT/4 + i, do_unhandled);

	for (i = 0; i < EXCCAUSE_N; i++) {

		set_handler(fast_user_handler, i, user_exception);

		set_handler(fast_kernel_handler, i, kernel_exception);

		set_handler(default_handler, i, do_unhandled);

	}



	/* Setup specific handlers. */
@@ -436,11 +435,11 @@ void __init trap_init(void) 
		void *handler = dispatch_init_table[i].handler;



		if (fast == 0)

			set_handler (EXC_TABLE_DEFAULT/4 + cause, handler);

			set_handler(default_handler, cause, handler);

		if (fast && fast & USER)

			set_handler (EXC_TABLE_FAST_USER/4 + cause, handler);

			set_handler(fast_user_handler, cause, handler);

		if (fast && fast & KRNL)

			set_handler (EXC_TABLE_FAST_KERNEL/4 + cause, handler);

			set_handler(fast_kernel_handler, cause, handler);

	}



	/* Initialize EXCSAVE_1 to hold the address of the exception table. */