~funderscore blog cgit wiki get in touch
aboutsummaryrefslogtreecommitdiff
blob: 9f5547e552d830b335b44aafb925f3256f899d04 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
 */

#include <asm-offsets.h>
#include <config.h>
#include <linux/linkage.h>
#include <asm/arcregs.h>
#include <system-constants.h>

ENTRY(_start)
	/* Setup interrupt vector base that matches "__text_start" */
	sr	__ivt_start, [ARC_AUX_INTR_VEC_BASE]

	; Disable/enable I-cache according to configuration
	lr	r5, [ARC_BCR_IC_BUILD]
	breq	r5, 0, 1f		; I$ doesn't exist
	lr	r5, [ARC_AUX_IC_CTRL]
#if !CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
	bclr	r5, r5, 0		; 0 - Enable, 1 is Disable
#else
	bset	r5, r5, 0		; I$ exists, but is not used
#endif
	sr	r5, [ARC_AUX_IC_CTRL]

	mov	r5, 1
	sr	r5, [ARC_AUX_IC_IVIC]
	; As per ARC HS databook (see chapter 5.3.3.2)
	; it is required to add 3 NOPs after each write to IC_IVIC.
	nop
	nop
	nop

1:
	; Disable/enable D-cache according to configuration
	lr	r5, [ARC_BCR_DC_BUILD]
	breq	r5, 0, 1f		; D$ doesn't exist
	lr	r5, [ARC_AUX_DC_CTRL]
	bclr	r5, r5, 6		; Invalidate (discard w/o wback)
#if !CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
	bclr	r5, r5, 0		; Enable (+Inv)
#else
	bset	r5, r5, 0		; Disable (+Inv)
#endif
	sr	r5, [ARC_AUX_DC_CTRL]

	mov	r5, 1
	sr	r5, [ARC_AUX_DC_IVDC]


1:
#ifdef CONFIG_ISA_ARCV2
	; Disable System-Level Cache (SLC)
	lr	r5, [ARC_BCR_SLC]
	breq	r5, 0, 1f		; SLC doesn't exist
	lr	r5, [ARC_AUX_SLC_CTRL]
	bclr	r5, r5, 6		; Invalidate (discard w/o wback)
	bclr	r5, r5, 0		; Enable (+Inv)
	sr	r5, [ARC_AUX_SLC_CTRL]

1:
#endif

#ifdef CONFIG_ISA_ARCV2
	; In case of DSP extension presence in HW some instructions
	; (related to integer multiply, multiply-accumulate, and divide
	; operation) executes on this DSP execution unit. So their
	; execution will depend on dsp configuration register (DSP_CTRL)
	; As we want these instructions to execute the same way regardless
	; of DSP presence we need to set DSP_CTRL properly.
	lr	r5, [ARC_AUX_DSP_BUILD]
	bmsk	r5, r5, 7
	breq    r5, 0, 1f
	mov	r5, 0
	sr	r5, [ARC_AUX_DSP_CTRL]
1:
#endif

#ifdef __ARC_UNALIGNED__
	/*
	 * Enable handling of unaligned access in the CPU as by default
	 * this HW feature is disabled while GCC starting from 8.1.0
	 * unconditionally uses it for ARC HS cores.
	 */
	flag	1 << STATUS_AD_BIT
#endif

	/* Establish C runtime stack and frame */
	mov	%sp, SYS_INIT_SP_ADDR
	mov	%fp, %sp

	/* Allocate reserved area from current top of stack */
	mov	%r0, %sp
	bl	board_init_f_alloc_reserve
	/* Set stack below reserved area, adjust frame pointer accordingly */
	mov	%sp, %r0
	mov	%fp, %sp

	/* Initialize reserved area - note: r0 already contains address */
	bl	board_init_f_init_reserve

#ifdef CONFIG_DEBUG_UART
	/* Earliest point to set up early debug uart */
	bl	debug_uart_init
#endif

	/* Zero the one and only argument of "board_init_f" */
	mov_s	%r0, 0
	bl	board_init_f

	/* We only get here if relocation is disabled by GD_FLG_SKIP_RELOC */
	/* Make sure we don't lose GD overwritten by zero new GD */
	mov	%r0, %r25
	mov	%r1, 0
	bl	board_init_r
ENDPROC(_start)

/*
 * void board_init_f_r_trampoline(stack-pointer address)
 *
 * This "function" does not return, instead it continues in RAM
 * after relocating the monitor code.
 *
 * r0 = new stack-pointer
 */
ENTRY(board_init_f_r_trampoline)
	/* Set up the stack- and frame-pointers */
	mov	%sp, %r0
	mov	%fp, %sp

	/* Update position of intterupt vector table */
	lr	%r0, [ARC_AUX_INTR_VEC_BASE]
	ld	%r1, [%r25, GD_RELOC_OFF]
	add	%r0, %r0, %r1
	sr	%r0, [ARC_AUX_INTR_VEC_BASE]

	/* Re-enter U-Boot by calling board_init_f_r */
	j	board_init_f_r
ENDPROC(board_init_f_r_trampoline)