xref: /OK3568_Linux_fs/kernel/arch/sh/include/asm/uncached.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef __ASM_SH_UNCACHED_H
3*4882a593Smuzhiyun #define __ASM_SH_UNCACHED_H
4*4882a593Smuzhiyun 
5*4882a593Smuzhiyun #include <linux/bug.h>
6*4882a593Smuzhiyun 
7*4882a593Smuzhiyun #ifdef CONFIG_UNCACHED_MAPPING
8*4882a593Smuzhiyun extern unsigned long cached_to_uncached;
9*4882a593Smuzhiyun extern unsigned long uncached_size;
10*4882a593Smuzhiyun extern unsigned long uncached_start, uncached_end;
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun extern int virt_addr_uncached(unsigned long kaddr);
13*4882a593Smuzhiyun extern void uncached_init(void);
14*4882a593Smuzhiyun extern void uncached_resize(unsigned long size);
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun /*
17*4882a593Smuzhiyun  * Jump to uncached area.
18*4882a593Smuzhiyun  * When handling TLB or caches, we need to do it from an uncached area.
19*4882a593Smuzhiyun  */
20*4882a593Smuzhiyun #define jump_to_uncached()			\
21*4882a593Smuzhiyun do {						\
22*4882a593Smuzhiyun 	unsigned long __dummy;			\
23*4882a593Smuzhiyun 						\
24*4882a593Smuzhiyun 	__asm__ __volatile__(			\
25*4882a593Smuzhiyun 		"mova	1f, %0\n\t"		\
26*4882a593Smuzhiyun 		"add	%1, %0\n\t"		\
27*4882a593Smuzhiyun 		"jmp	@%0\n\t"		\
28*4882a593Smuzhiyun 		" nop\n\t"			\
29*4882a593Smuzhiyun 		".balign 4\n"			\
30*4882a593Smuzhiyun 		"1:"				\
31*4882a593Smuzhiyun 		: "=&z" (__dummy)		\
32*4882a593Smuzhiyun 		: "r" (cached_to_uncached));	\
33*4882a593Smuzhiyun } while (0)
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun /*
36*4882a593Smuzhiyun  * Back to cached area.
37*4882a593Smuzhiyun  */
38*4882a593Smuzhiyun #define back_to_cached()				\
39*4882a593Smuzhiyun do {							\
40*4882a593Smuzhiyun 	unsigned long __dummy;				\
41*4882a593Smuzhiyun 	ctrl_barrier();					\
42*4882a593Smuzhiyun 	__asm__ __volatile__(				\
43*4882a593Smuzhiyun 		"mov.l	1f, %0\n\t"			\
44*4882a593Smuzhiyun 		"jmp	@%0\n\t"			\
45*4882a593Smuzhiyun 		" nop\n\t"				\
46*4882a593Smuzhiyun 		".balign 4\n"				\
47*4882a593Smuzhiyun 		"1:	.long 2f\n"			\
48*4882a593Smuzhiyun 		"2:"					\
49*4882a593Smuzhiyun 		: "=&r" (__dummy));			\
50*4882a593Smuzhiyun } while (0)
51*4882a593Smuzhiyun #else
52*4882a593Smuzhiyun #define virt_addr_uncached(kaddr)	(0)
53*4882a593Smuzhiyun #define uncached_init()			do { } while (0)
54*4882a593Smuzhiyun #define uncached_resize(size)		BUG()
55*4882a593Smuzhiyun #define jump_to_uncached()		do { } while (0)
56*4882a593Smuzhiyun #define back_to_cached()		do { } while (0)
57*4882a593Smuzhiyun #endif
58*4882a593Smuzhiyun 
59*4882a593Smuzhiyun #endif /* __ASM_SH_UNCACHED_H */
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