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armv6: bcm2835 & qvpb have nearly identical locore _start
It makes sense to common-ize _start for all armv6 machines. They will all
have to do the same basic setup. If there is any machine specific setup
they need to do, they can do so in the new _mach_start function.
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--- old/usr/src/uts/armv6/qvpb/ml/locore.s
+++ new/usr/src/uts/armv6/qvpb/ml/locore.s
1 1 /*
2 2 * This file and its contents are supplied under the terms of the
3 3 * Common Development and Distribution License ("CDDL"), version 1.0.
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4 4 * You may only use this file in accordance with the terms of version
5 5 * 1.0 of the CDDL.
6 6 *
7 7 * A full copy of the text of the CDDL should have accompanied this
8 8 * source. A copy of the CDDL is also available via the Internet at
9 9 * http://www.illumos.org/license/CDDL.
10 10 */
11 11
12 12 /*
13 13 * Copyright 2013 (c) Joyent, Inc. All rights reserved.
14 + * Copyright 2015 (c) Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
14 15 */
15 16
16 17 #include <sys/asm_linkage.h>
17 18 #include <sys/machparam.h>
18 19 #include <sys/cpu_asm.h>
19 20
20 -/*
21 - * Every story needs a beginning. This is ours.
22 - */
23 -
24 -/*
25 - * We are in a primordial world here. The BMC2835 is going to come along and
26 - * boot us at _start. Normally we would go ahead and use a main() function, but
27 - * for now, we'll do that ourselves. As we've started the world, we also need to
28 - * set up a few things about us, for example our stack pointer. To help us out,
29 - * it's useful to remember the rough memory map. Remember, this is for physcial
30 - * addresses. There is no virtual memory here. These sizes are often manipulated
31 - * by the 'configuration' in the bootloader.
32 - *
33 - * +----------------+ <---- Max physical memory
34 - * | |
35 - * | |
36 - * | |
37 - * +----------------+
38 - * | |
39 - * | I/O |
40 - * | Peripherals |
41 - * | |
42 - * +----------------+ <---- I/O base 0x20000000 (corresponds to 0x7E000000)
43 - * | |
44 - * | Main |
45 - * | Memory |
46 - * | |
47 - * +----------------+ <---- Top of SDRAM
48 - * | |
49 - * | VC |
50 - * | SDRAM |
51 - * | |
52 - * +----------------+ <---- Split determined by bootloader config
53 - * | |
54 - * | ARM |
55 - * | SDRAM |
56 - * | |
57 - * +----------------+ <---- Bottom of physical memory 0x00000000
58 - *
59 - * With the Raspberry Pi Model B, we have 512 MB of SDRAM. That means we have a
60 - * range of addresses from [0, 0x20000000). If we assume that the minimum amount
61 - * of DRAM is given to the GPU - 32 MB, that means we really have the following
62 - * range: [0, 0x1e000000).
63 - *
64 - * By default, this binary will be loaded into 0x8000. For now, that means we
65 - * will set our initial stack to 0x10000000.
66 - */
67 -
68 -/*
69 - * Recall that _start is the traditional entry point for an ELF binary.
70 - */
71 - ENTRY(_start)
72 - ldr sp, =t0stack
73 - ldr r4, =DEFAULTSTKSZ
74 - add sp, r4
75 - bic sp, sp, #0xff
76 -
77 - /*
78 - * establish bogus stacks for exceptional CPU states, our exception
79 - * code should never make use of these, and we want loud and violent
80 - * failure should we accidentally try.
81 - */
82 - cps #(CPU_MODE_UND)
83 - mov sp, #-1
84 - cps #(CPU_MODE_ABT)
85 - mov sp, #-1
86 - cps #(CPU_MODE_FIQ)
87 - mov sp, #-1
88 - cps #(CPU_MODE_IRQ)
89 - mov sp, #-1
90 - cps #(CPU_MODE_SVC)
91 -
92 - /* Enable highvecs (moves the base of the exception vector) */
93 - mrc p15, 0, r3, c1, c0, 0
94 - mov r4, #1
95 - lsl r4, r4, #13
96 - orr r3, r3, r4
97 - mcr p15, 0, r3, c1, c0, 0
98 -
99 - bl _fakebop_start
100 - SET_SIZE(_start)
101 -
102 - ENTRY(arm_reg_read)
103 - ldr r0, [r0]
104 - bx lr
105 - SET_SIZE(arm_reg_read)
106 -
107 - ENTRY(arm_reg_write)
108 - str r1, [r0]
109 - bx lr
110 - SET_SIZE(arm_reg_write)
21 + ENTRY(_mach_start)
22 + /* nothing to do */
23 + bx r14
24 + SET_SIZE(_mach_start)
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