xref: /rk3399_ARM-atf/lib/aarch32/misc_helpers.S (revision 3d8256b2a1ef1195aed86bef7378e83d0a61a91b)
1/*
2 * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are met:
6 *
7 * Redistributions of source code must retain the above copyright notice, this
8 * list of conditions and the following disclaimer.
9 *
10 * Redistributions in binary form must reproduce the above copyright notice,
11 * this list of conditions and the following disclaimer in the documentation
12 * and/or other materials provided with the distribution.
13 *
14 * Neither the name of ARM nor the names of its contributors may be used
15 * to endorse or promote products derived from this software without specific
16 * prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#include <arch.h>
32#include <asm_macros.S>
33#include <assert_macros.S>
34
35	.globl	smc
36	.globl	zeromem
37	.globl	memcpy4
38	.globl	disable_mmu_icache_secure
39	.globl	disable_mmu_secure
40
41func smc
42	/*
43	 * For AArch32 only r0-r3 will be in the registers;
44	 * rest r4-r6 will be pushed on to the stack. So here, we'll
45	 * have to load them from the stack to registers r4-r6 explicitly.
46	 * Clobbers: r4-r6
47	 */
48	ldm	sp, {r4, r5, r6}
49	smc	#0
50endfunc smc
51
52/* -----------------------------------------------------------------------
53 * void zeromem(void *mem, unsigned int length);
54 *
55 * Initialise a memory region to 0.
56 * The memory address and length must be 4-byte aligned.
57 * -----------------------------------------------------------------------
58 */
59func zeromem
60#if ASM_ASSERTION
61	tst	r0, #0x3
62	ASM_ASSERT(eq)
63	tst	r1, #0x3
64	ASM_ASSERT(eq)
65#endif
66	add	r2, r0, r1
67	mov	r1, #0
68z_loop:
69	cmp	r2, r0
70	beq	z_end
71	str	r1, [r0], #4
72	b	z_loop
73z_end:
74	bx	lr
75endfunc zeromem
76
77/* --------------------------------------------------------------------------
78 * void memcpy4(void *dest, const void *src, unsigned int length)
79 *
80 * Copy length bytes from memory area src to memory area dest.
81 * The memory areas should not overlap.
82 * Destination and source addresses must be 4-byte aligned.
83 * --------------------------------------------------------------------------
84 */
85func memcpy4
86#if ASM_ASSERTION
87	orr	r3, r0, r1
88	tst	r3, #0x3
89	ASM_ASSERT(eq)
90#endif
91/* copy 4 bytes at a time */
92m_loop4:
93	cmp	r2, #4
94	blt	m_loop1
95	ldr	r3, [r1], #4
96	str	r3, [r0], #4
97	sub	r2, r2, #4
98	b	m_loop4
99/* copy byte per byte */
100m_loop1:
101	cmp	r2,#0
102	beq	m_end
103	ldrb	r3, [r1], #1
104	strb	r3, [r0], #1
105	subs	r2, r2, #1
106	bne	m_loop1
107m_end:
108	bx	lr
109endfunc memcpy4
110
111/* ---------------------------------------------------------------------------
112 * Disable the MMU in Secure State
113 * ---------------------------------------------------------------------------
114 */
115
116func disable_mmu_secure
117	mov	r1, #(SCTLR_M_BIT | SCTLR_C_BIT)
118do_disable_mmu:
119	ldcopr	r0, SCTLR
120	bic	r0, r0, r1
121	stcopr	r0, SCTLR
122	isb				// ensure MMU is off
123	dsb	sy
124	bx	lr
125endfunc disable_mmu_secure
126
127
128func disable_mmu_icache_secure
129	ldr	r1, =(SCTLR_M_BIT | SCTLR_C_BIT | SCTLR_I_BIT)
130	b	do_disable_mmu
131endfunc disable_mmu_icache_secure
132