xref: /openbmc/u-boot/arch/arm/cpu/armv8/cache.S (revision ee7bb5be)
1/*
2 * (C) Copyright 2013
3 * David Feng <fenghua@phytium.com.cn>
4 *
5 * This file is based on sample code from ARMv8 ARM.
6 *
7 * SPDX-License-Identifier:	GPL-2.0+
8 */
9
10#include <asm-offsets.h>
11#include <config.h>
12#include <asm/macro.h>
13#include <asm/system.h>
14#include <linux/linkage.h>
15
16/*
17 * void __asm_flush_dcache_level(level)
18 *
19 * clean and invalidate one level cache.
20 *
21 * x0: cache level
22 * x1: 0 flush & invalidate, 1 invalidate only
23 * x2~x9: clobbered
24 */
25ENTRY(__asm_flush_dcache_level)
26	lsl	x12, x0, #1
27	msr	csselr_el1, x12		/* select cache level */
28	isb				/* sync change of cssidr_el1 */
29	mrs	x6, ccsidr_el1		/* read the new cssidr_el1 */
30	and	x2, x6, #7		/* x2 <- log2(cache line size)-4 */
31	add	x2, x2, #4		/* x2 <- log2(cache line size) */
32	mov	x3, #0x3ff
33	and	x3, x3, x6, lsr #3	/* x3 <- max number of #ways */
34	clz	w5, w3			/* bit position of #ways */
35	mov	x4, #0x7fff
36	and	x4, x4, x6, lsr #13	/* x4 <- max number of #sets */
37	/* x12 <- cache level << 1 */
38	/* x2 <- line length offset */
39	/* x3 <- number of cache ways - 1 */
40	/* x4 <- number of cache sets - 1 */
41	/* x5 <- bit position of #ways */
42
43loop_set:
44	mov	x6, x3			/* x6 <- working copy of #ways */
45loop_way:
46	lsl	x7, x6, x5
47	orr	x9, x12, x7		/* map way and level to cisw value */
48	lsl	x7, x4, x2
49	orr	x9, x9, x7		/* map set number to cisw value */
50	tbz	w1, #0, 1f
51	dc	isw, x9
52	b	2f
531:	dc	cisw, x9		/* clean & invalidate by set/way */
542:	subs	x6, x6, #1		/* decrement the way */
55	b.ge	loop_way
56	subs	x4, x4, #1		/* decrement the set */
57	b.ge	loop_set
58
59	ret
60ENDPROC(__asm_flush_dcache_level)
61
62/*
63 * void __asm_flush_dcache_all(int invalidate_only)
64 *
65 * x0: 0 flush & invalidate, 1 invalidate only
66 *
67 * clean and invalidate all data cache by SET/WAY.
68 */
69ENTRY(__asm_dcache_all)
70	mov	x1, x0
71	dsb	sy
72	mrs	x10, clidr_el1		/* read clidr_el1 */
73	lsr	x11, x10, #24
74	and	x11, x11, #0x7		/* x11 <- loc */
75	cbz	x11, finished		/* if loc is 0, exit */
76	mov	x15, lr
77	mov	x0, #0			/* start flush at cache level 0 */
78	/* x0  <- cache level */
79	/* x10 <- clidr_el1 */
80	/* x11 <- loc */
81	/* x15 <- return address */
82
83loop_level:
84	lsl	x12, x0, #1
85	add	x12, x12, x0		/* x0 <- tripled cache level */
86	lsr	x12, x10, x12
87	and	x12, x12, #7		/* x12 <- cache type */
88	cmp	x12, #2
89	b.lt	skip			/* skip if no cache or icache */
90	bl	__asm_flush_dcache_level	/* x1 = 0 flush, 1 invalidate */
91skip:
92	add	x0, x0, #1		/* increment cache level */
93	cmp	x11, x0
94	b.gt	loop_level
95
96	mov	x0, #0
97	msr	csselr_el1, x0		/* restore csselr_el1 */
98	dsb	sy
99	isb
100	mov	lr, x15
101
102finished:
103	ret
104ENDPROC(__asm_dcache_all)
105
106ENTRY(__asm_flush_dcache_all)
107	mov	x16, lr
108	mov	x0, #0
109	bl	__asm_dcache_all
110	mov	lr, x16
111	ret
112ENDPROC(__asm_flush_dcache_all)
113
114ENTRY(__asm_invalidate_dcache_all)
115	mov	x16, lr
116	mov	x0, #0x1
117	bl	__asm_dcache_all
118	mov	lr, x16
119	ret
120ENDPROC(__asm_invalidate_dcache_all)
121
122/*
123 * void __asm_flush_dcache_range(start, end)
124 *
125 * clean & invalidate data cache in the range
126 *
127 * x0: start address
128 * x1: end address
129 */
130ENTRY(__asm_flush_dcache_range)
131	mrs	x3, ctr_el0
132	lsr	x3, x3, #16
133	and	x3, x3, #0xf
134	mov	x2, #4
135	lsl	x2, x2, x3		/* cache line size */
136
137	/* x2 <- minimal cache line size in cache system */
138	sub	x3, x2, #1
139	bic	x0, x0, x3
1401:	dc	civac, x0	/* clean & invalidate data or unified cache */
141	add	x0, x0, x2
142	cmp	x0, x1
143	b.lo	1b
144	dsb	sy
145	ret
146ENDPROC(__asm_flush_dcache_range)
147
148/*
149 * void __asm_invalidate_icache_all(void)
150 *
151 * invalidate all tlb entries.
152 */
153ENTRY(__asm_invalidate_icache_all)
154	ic	ialluis
155	isb	sy
156	ret
157ENDPROC(__asm_invalidate_icache_all)
158
159ENTRY(__asm_flush_l3_cache)
160	mov	x0, #0			/* return status as success */
161	ret
162ENDPROC(__asm_flush_l3_cache)
163	.weak	__asm_flush_l3_cache
164
165/*
166 * void __asm_switch_ttbr(ulong new_ttbr)
167 *
168 * Safely switches to a new page table.
169 */
170ENTRY(__asm_switch_ttbr)
171	/* x2 = SCTLR (alive throghout the function) */
172	switch_el x4, 3f, 2f, 1f
1733:	mrs	x2, sctlr_el3
174	b	0f
1752:	mrs	x2, sctlr_el2
176	b	0f
1771:	mrs	x2, sctlr_el1
1780:
179
180	/* Unset CR_M | CR_C | CR_I from SCTLR to disable all caches */
181	movn	x1, #(CR_M | CR_C | CR_I)
182	and	x1, x2, x1
183	switch_el x4, 3f, 2f, 1f
1843:	msr	sctlr_el3, x1
185	b	0f
1862:	msr	sctlr_el2, x1
187	b	0f
1881:	msr	sctlr_el1, x1
1890:	isb
190
191	/* This call only clobbers x30 (lr) and x9 (unused) */
192	mov	x3, x30
193	bl	__asm_invalidate_tlb_all
194
195	/* From here on we're running safely with caches disabled */
196
197	/* Set TTBR to our first argument */
198	switch_el x4, 3f, 2f, 1f
1993:	msr	ttbr0_el3, x0
200	b	0f
2012:	msr	ttbr0_el2, x0
202	b	0f
2031:	msr	ttbr0_el1, x0
2040:	isb
205
206	/* Restore original SCTLR and thus enable caches again */
207	switch_el x4, 3f, 2f, 1f
2083:	msr	sctlr_el3, x2
209	b	0f
2102:	msr	sctlr_el2, x2
211	b	0f
2121:	msr	sctlr_el1, x2
2130:	isb
214
215	ret	x3
216ENDPROC(__asm_switch_ttbr)
217