1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 
3 /* From asm-compat.h */
4 #define __stringify_in_c(...)	#__VA_ARGS__
5 #define stringify_in_c(...)	__stringify_in_c(__VA_ARGS__) " "
6 
7 /*
8  * Macros taken from arch/powerpc/include/asm/ppc-opcode.h and other
9  * header files.
10  */
11 #define ___PPC_RA(a)    (((a) & 0x1f) << 16)
12 #define ___PPC_RB(b)    (((b) & 0x1f) << 11)
13 
14 #define PPC_INST_COPY                   0x7c20060c
15 #define PPC_INST_PASTE                  0x7c20070d
16 
17 #define PPC_COPY(a, b)          stringify_in_c(.long PPC_INST_COPY | \
18 						___PPC_RA(a) | ___PPC_RB(b))
19 #define PPC_PASTE(a, b)         stringify_in_c(.long PPC_INST_PASTE | \
20 						___PPC_RA(a) | ___PPC_RB(b))
21 #define CR0_SHIFT	28
22 #define CR0_MASK	0xF
23 /*
24  * Copy/paste instructions:
25  *
26  *	copy RA,RB
27  *		Copy contents of address (RA) + effective_address(RB)
28  *		to internal copy-buffer.
29  *
30  *	paste RA,RB
31  *		Paste contents of internal copy-buffer to the address
32  *		(RA) + effective_address(RB)
33  */
34 static inline int vas_copy(void *crb, int offset)
35 {
36 	asm volatile(PPC_COPY(%0, %1)";"
37 		:
38 		: "b" (offset), "b" (crb)
39 		: "memory");
40 
41 	return 0;
42 }
43 
44 static inline int vas_paste(void *paste_address, int offset)
45 {
46 	__u32 cr;
47 
48 	cr = 0;
49 	asm volatile(PPC_PASTE(%1, %2)";"
50 		"mfocrf %0, 0x80;"
51 		: "=r" (cr)
52 		: "b" (offset), "b" (paste_address)
53 		: "memory", "cr0");
54 
55 	return (cr >> CR0_SHIFT) & CR0_MASK;
56 }
57