Commit 50722f0b authored by Max Filippov's avatar Max Filippov
Browse files

xtensa: move fast exception handlers close to vectors 



On XIP kernels it makes sense to have exception vectors and fast
exception handlers together (in a fast memory). In addition, with MTD
XIP support both vectors and fast exception handlers must be outside of
the FLASH.

Add section .exception.text and move fast exception handlers to it.
Put it together with vectors when vectors are outside of the .text.

Signed-off-by: default avatarMax Filippov <jcmvbkbc@gmail.com>
parent 58bc6c69

arch/xtensa/include/asm/asmmacro.h

+2 −0
Original line number Diff line number Diff line
@@ -237,4 +237,6 @@ 
#error Unsupported Xtensa ABI

#endif



#define __XTENSA_HANDLER	.section ".exception.text", "ax"



#endif /* _XTENSA_ASMMACRO_H */

arch/xtensa/kernel/coprocessor.S

+2 −3
Original line number Diff line number Diff line
@@ -58,6 +58,8 @@ 
	.endif;								\

	.long THREAD_XTREGS_CP##x



	__XTENSA_HANDLER



	SAVE_CP_REGS(0)

	SAVE_CP_REGS(1)

	SAVE_CP_REGS(2)
@@ -76,7 +78,6 @@ 
	LOAD_CP_REGS(6)

	LOAD_CP_REGS(7)



	.section ".rodata", "a"

	.align 4

.Lsave_cp_regs_jump_table:

	SAVE_CP_REGS_TAB(0)
@@ -98,8 +99,6 @@ 
	LOAD_CP_REGS_TAB(6)

	LOAD_CP_REGS_TAB(7)



	.previous



/*

 * coprocessor_flush(struct thread_info*, index)

 *                             a2        a3

arch/xtensa/kernel/entry.S

+12 −6
Original line number Diff line number Diff line
@@ -939,6 +939,9 @@ ENDPROC(unrecoverable_exception) 


/* -------------------------- FAST EXCEPTION HANDLERS ----------------------- */



	__XTENSA_HANDLER

	.literal_position



/*

 * Fast-handler for alloca exceptions

 *
@@ -1024,7 +1027,7 @@ ENDPROC(fast_alloca) 
ENTRY(fast_illegal_instruction_user)



	rsr	a0, ps

	bbsi.l	a0, PS_WOE_BIT, user_exception

	bbsi.l	a0, PS_WOE_BIT, 1f

	s32i	a3, a2, PT_AREG3

	movi	a3, PS_WOE_MASK

	or	a0, a0, a3
@@ -1033,6 +1036,8 @@ ENTRY(fast_illegal_instruction_user) 
	l32i	a0, a2, PT_AREG0

	rsr	a2, depc

	rfe

1:

	call0	user_exception



ENDPROC(fast_illegal_instruction_user)

#endif
@@ -1071,7 +1076,7 @@ ENTRY(fast_syscall_user) 
	_beqz	a0, fast_syscall_spill_registers

	_beqi	a0, __NR_xtensa, fast_syscall_xtensa



	j	user_exception

	call0	user_exception



ENDPROC(fast_syscall_user)
@@ -1762,8 +1767,8 @@ ENTRY(fast_second_level_miss) 


	rsr	a2, ps

	bbsi.l	a2, PS_UM_BIT, 1f

	j	_kernel_exception

1:	j	_user_exception

	call0	_kernel_exception

1:	call0	_user_exception



ENDPROC(fast_second_level_miss)
@@ -1859,13 +1864,14 @@ ENTRY(fast_store_prohibited) 


	rsr	a2, ps

	bbsi.l	a2, PS_UM_BIT, 1f

	j	_kernel_exception

1:	j	_user_exception

	call0	_kernel_exception

1:	call0	_user_exception



ENDPROC(fast_store_prohibited)



#endif /* CONFIG_MMU */



	.text

/*

 * System Calls.

 *

arch/xtensa/kernel/setup.c

+4 −0
Original line number Diff line number Diff line
@@ -284,6 +284,8 @@ extern char _UserExceptionVector_text_start; 
extern char _UserExceptionVector_text_end;

extern char _DoubleExceptionVector_text_start;

extern char _DoubleExceptionVector_text_end;

extern char _exception_text_start;

extern char _exception_text_end;

#if XCHAL_EXCM_LEVEL >= 2

extern char _Level2InterruptVector_text_start;

extern char _Level2InterruptVector_text_end;
@@ -363,6 +365,8 @@ void __init setup_arch(char **cmdline_p) 
	mem_reserve(__pa(&_DoubleExceptionVector_text_start),

		    __pa(&_DoubleExceptionVector_text_end));



	mem_reserve(__pa(&_exception_text_start),

		    __pa(&_exception_text_end));

#if XCHAL_EXCM_LEVEL >= 2

	mem_reserve(__pa(&_Level2InterruptVector_text_start),

		    __pa(&_Level2InterruptVector_text_end));

arch/xtensa/kernel/vectors.S

+2 −1
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ 
 */



#include <linux/linkage.h>

#include <asm/asmmacro.h>

#include <asm/ptrace.h>

#include <asm/current.h>

#include <asm/asm-offsets.h>
@@ -477,7 +478,6 @@ _DoubleExceptionVector_handle_exception: 


ENDPROC(_DoubleExceptionVector)



	.text

/*

 * Fixup handler for TLB miss in double exception handler for window owerflow.

 * We get here with windowbase set to the window that was being spilled and
@@ -505,6 +505,7 @@ ENDPROC(_DoubleExceptionVector) 
 * a3: exctable, original value in excsave1

 */



	__XTENSA_HANDLER

	.literal_position



ENTRY(window_overflow_restore_a0_fixup)

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