/*
 * arch/arm/kernel/kprobes-test.h
 *
 * Copyright (C) 2011 Jon Medhurst <tixy@yxit.co.uk>.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#define VERBOSE 0 /* Set to '1' for more logging of test cases */

#ifdef CONFIG_THUMB2_KERNEL
#define NORMAL_ISA "16"
#else
#define NORMAL_ISA "32"
#endif


/* Flags used in kprobe_test_flags */
#define TEST_FLAG_NO_ITBLOCK	(1<<0)
#define TEST_FLAG_FULL_ITBLOCK	(1<<1)
#define TEST_FLAG_NARROW_INSTR	(1<<2)

extern int kprobe_test_flags;
extern int kprobe_test_cc_position;


#define TEST_MEMORY_SIZE 256


/*
 * Test case structures.
 *
 * The arguments given to test cases can be one of three types.
 *
 *   ARG_TYPE_REG
 *	Load a register with the given value.
 *
 *   ARG_TYPE_PTR
 *	Load a register with a pointer into the stack buffer (SP + given value).
 *
 *   ARG_TYPE_MEM
 *	Store the given value into the stack buffer at [SP+index].
 *
 */

#define	ARG_TYPE_END	0
#define	ARG_TYPE_REG	1
#define	ARG_TYPE_PTR	2
#define	ARG_TYPE_MEM	3

#define ARG_FLAG_UNSUPPORTED	0x01
#define ARG_FLAG_SUPPORTED	0x02
#define ARG_FLAG_THUMB		0x10	/* Must be 16 so TEST_ISA can be used */
#define ARG_FLAG_ARM		0x20	/* Must be 32 so TEST_ISA can be used */

struct test_arg {
	u8	type;		/* ARG_TYPE_x */
	u8	_padding[7];
};

struct test_arg_regptr {
	u8	type;		/* ARG_TYPE_REG or ARG_TYPE_PTR */
	u8	reg;
	u8	_padding[2];
	u32	val;
};

struct test_arg_mem {
	u8	type;		/* ARG_TYPE_MEM */
	u8	index;
	u8	_padding[2];
	u32	val;
};

struct test_arg_end {
	u8	type;		/* ARG_TYPE_END */
	u8	flags;		/* ARG_FLAG_x */
	u16	code_offset;
	u16	branch_offset;
	u16	end_offset;
};


/*
 * Building blocks for test cases.
 *
 * Each test case is wrapped between TESTCASE_START and TESTCASE_END.
 *
 * To specify arguments for a test case the TEST_ARG_{REG,PTR,MEM} macros are
 * used followed by a terminating TEST_ARG_END.
 *
 * After this, the instruction to be tested is defined with TEST_INSTRUCTION.
 * Or for branches, TEST_BRANCH_B and TEST_BRANCH_F (branch forwards/backwards).
 *
 * Some specific test cases may make use of other custom constructs.
 */

#if VERBOSE
#define verbose(fmt, ...) pr_info(fmt, ##__VA_ARGS__)
#else
#define verbose(fmt, ...)
#endif

#define TEST_GROUP(title)					\
	verbose("\n");						\
	verbose(title"\n");					\
	verbose("---------------------------------------------------------\n");

#define TESTCASE_START(title)					\
	__asm__ __volatile__ (					\
	"bl	__kprobes_test_case_start		\n\t"	\
	/* don't use .asciz here as 'title' may be */		\
	/* multiple strings to be concatenated.  */		\
	".ascii "#title"				\n\t"	\
	".byte	0					\n\t"	\
	".align	2					\n\t"

#define	TEST_ARG_REG(reg, val)					\
	".byte	"__stringify(ARG_TYPE_REG)"		\n\t"	\
	".byte	"#reg"					\n\t"	\
	".short	0					\n\t"	\
	".word	"#val"					\n\t"

#define	TEST_ARG_PTR(reg, val)					\
	".byte	"__stringify(ARG_TYPE_PTR)"		\n\t"	\
	".byte	"#reg"					\n\t"	\
	".short	0					\n\t"	\
	".word	"#val"					\n\t"

#define	TEST_ARG_MEM(index, val)				\
	".byte	"__stringify(ARG_TYPE_MEM)"		\n\t"	\
	".byte	"#index"				\n\t"	\
	".short	0					\n\t"	\
	".word	"#val"					\n\t"

#define	TEST_ARG_END(flags)					\
	".byte	"__stringify(ARG_TYPE_END)"		\n\t"	\
	".byte	"TEST_ISA flags"			\n\t"	\
	".short	50f-0f					\n\t"	\
	".short	2f-0f					\n\t"	\
	".short	99f-0f					\n\t"	\
	".code "TEST_ISA"				\n\t"	\
	"0:						\n\t"

#define TEST_INSTRUCTION(instruction)				\
	"50:	nop					\n\t"	\
	"1:	"instruction"				\n\t"	\
	"	nop					\n\t"