/*
 *  Copyright (C) 2006 Giridhar Pemmasani
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *  GNU General Public License for more details.
 *
 */

#ifdef CONFIG_X86_64

/* Windows functions must have 32 bytes of shadow space for arguments
 * above return address, irrespective of number of args. So argc >= 4
 */

#define alloc_win_stack_frame(argc)		\
	"sub $(" #argc "+1)*8, %%rsp\n\t"
#define free_win_stack_frame(argc)		\
	"add $(" #argc "+1)*8, %%rsp\n\t"

/* m is index of Windows arg required; Windows arg 1 should be at
 * 0(%rsp), arg 2 at 8(%rsp) and so on after the frame is allocated.
*/

#define lin2win_win_arg(m) "(" #m "-1)*8(%%rsp)"

/* args for Windows function must be in clobber / output list */

#define outputs()							\
	"=a" (_ret), "=c" (_dummy), "=d" (_dummy),			\
		"=r" (r8), "=r" (r9), "=r" (r10), "=r" (r11)

#define clobbers() "cc"

#define LIN2WIN0(func)							\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8");					\
	register u64 r9 __asm__("r9");					\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(4)				\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(4)					\
		: outputs()						\
		: [fptr] "r" (func)					\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN1(func, arg1)						\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8");					\
	register u64 r9 __asm__("r9");					\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(4)				\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(4)					\
		: outputs()						\
		: "c" (arg1), [fptr] "r" (func)				\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN2(func, arg1, arg2)					\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8");					\
	register u64 r9 __asm__("r9");					\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(4)				\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(4)					\
		: outputs()						\
		: "c" (arg1), "d" (arg2), [fptr] "r" (func)		\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN3(func, arg1, arg2, arg3)				\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8") = (u64)arg3;			\
	register u64 r9 __asm__("r9");					\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(4)				\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(4)					\
		: outputs()						\
		: "c" (arg1), "d" (arg2), "r" (r8),			\
		  [fptr] "r" (func)					\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN4(func, arg1, arg2, arg3, arg4)				\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8") = (u64)arg3;			\
	register u64 r9 __asm__("r9") = (u64)arg4;			\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(4)				\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(4)					\
		: outputs()						\
		: "c" (arg1), "d" (arg2), "r" (r8), "r" (r9),		\
		  [fptr] "r" (func)					\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN5(func, arg1, arg2, arg3, arg4, arg5)			\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8") = (u64)arg3;			\
	register u64 r9 __asm__("r9") = (u64)arg4;			\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(5)				\
		"movq %[rarg5], " lin2win_win_arg(5) "\n\t"		\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(5)					\
		: outputs()						\
		: "c" (arg1), "d" (arg2), "r" (r8), "r" (r9),		\
		  [rarg5] "ri" ((u64)arg5),				\
		  [fptr] "r" (func)					\
		: clobbers());						\
	_ret;								\
})

#define LIN2WIN6(func, arg1, arg2, arg3, arg4, arg5, arg6)		\
({									\
	u64 _ret, _dummy;						\
	register u64 r8 __asm__("r8") = (u64)arg3;			\
	register u64 r9 __asm__("r9") = (u64)arg4;			\
	register u64 r10 __asm__("r10");				\
	register u64 r11 __asm__("r11");				\
	__asm__ __volatile__(						\
		alloc_win_stack_frame(6)				\
		"movq %[rarg5], " lin2win_win_arg(5) "\n\t"		\
		"movq %[rarg6], " lin2win_win_arg(6) "\n\t"		\
		"callq *%[fptr]\n\t"					\
		free_win_stack_frame(6)					\
		: outputs()						\
		: "c" (arg1), "d" (arg2), "r" (r8), "r" (r9),		\
		  [rarg5] "ri" ((u64)arg5), [rarg6] "ri" ((u64)arg6),	\
		  [fptr] "r" (func)					\
		: clobbers());						\
	_ret;								\
})

#else // CONFIG_X86_64

#define LIN2WIN1(func, arg1)						\
({									\
	TRACE6("calling %p", func);					\
	func(arg1);							\
})
#define LIN2WIN2(func, arg1, arg2)					\
({									\
	TRACE6("calling %p", func);					\
	func(arg1, arg2);						\
})
#define LIN2WIN3(func, arg1, arg2, arg3)				\
({									\
	TRACE6("calling %p", func);					\
	func(arg1, arg2, arg3);						\
})
#define LIN2WIN4(func, arg1, arg2, arg3, arg4)				\
({									\
	TRACE6("calling %p", func);					\
	func(arg1, arg2, arg3, arg4);					\
})
#define LIN2WIN5(func, arg1, arg2, arg3, arg4, arg5)			\
({									\
	TRACE6("calling %p", func);					\
	func(arg1, arg2, arg3, arg4, arg5);				\
})
#define LIN2WIN6(func, arg1, arg2, arg3, arg4, arg5, arg6)		\
({									\
	TRACE6("calling %p", func);					\
	func(arg1, arg2, arg3, arg4, arg5, arg6);			\
})

#endif // CONFIG_X86_64