xref: /openbmc/linux/arch/arm/mm/proc-arm740.S (revision 588b48ca)
1/*
2 *  linux/arch/arm/mm/arm740.S: utility functions for ARM740
3 *
4 *  Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com)
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11#include <linux/linkage.h>
12#include <linux/init.h>
13#include <asm/assembler.h>
14#include <asm/asm-offsets.h>
15#include <asm/hwcap.h>
16#include <asm/pgtable-hwdef.h>
17#include <asm/pgtable.h>
18#include <asm/ptrace.h>
19
20#include "proc-macros.S"
21
22	.text
23/*
24 * cpu_arm740_proc_init()
25 * cpu_arm740_do_idle()
26 * cpu_arm740_dcache_clean_area()
27 * cpu_arm740_switch_mm()
28 *
29 * These are not required.
30 */
31ENTRY(cpu_arm740_proc_init)
32ENTRY(cpu_arm740_do_idle)
33ENTRY(cpu_arm740_dcache_clean_area)
34ENTRY(cpu_arm740_switch_mm)
35	ret	lr
36
37/*
38 * cpu_arm740_proc_fin()
39 */
40ENTRY(cpu_arm740_proc_fin)
41	mrc	p15, 0, r0, c1, c0, 0
42	bic	r0, r0, #0x3f000000		@ bank/f/lock/s
43	bic	r0, r0, #0x0000000c		@ w-buffer/cache
44	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
45	ret	lr
46
47/*
48 * cpu_arm740_reset(loc)
49 * Params  : r0 = address to jump to
50 * Notes   : This sets up everything for a reset
51 */
52	.pushsection	.idmap.text, "ax"
53ENTRY(cpu_arm740_reset)
54	mov	ip, #0
55	mcr	p15, 0, ip, c7, c0, 0		@ invalidate cache
56	mrc	p15, 0, ip, c1, c0, 0		@ get ctrl register
57	bic	ip, ip, #0x0000000c		@ ............wc..
58	mcr	p15, 0, ip, c1, c0, 0		@ ctrl register
59	ret	r0
60ENDPROC(cpu_arm740_reset)
61	.popsection
62
63	.type	__arm740_setup, #function
64__arm740_setup:
65	mov	r0, #0
66	mcr	p15, 0, r0, c7, c0, 0		@ invalidate caches
67
68	mcr	p15, 0, r0, c6, c3		@ disable area 3~7
69	mcr	p15, 0, r0, c6, c4
70	mcr	p15, 0, r0, c6, c5
71	mcr	p15, 0, r0, c6, c6
72	mcr	p15, 0, r0, c6, c7
73
74	mov	r0, #0x0000003F			@ base = 0, size = 4GB
75	mcr	p15, 0, r0, c6,	c0		@ set area 0, default
76
77	ldr	r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM
78	ldr	r3, =(CONFIG_DRAM_SIZE >> 12)	@ size of RAM (must be >= 4KB)
79	mov	r4, #10				@ 11 is the minimum (4KB)
801:	add	r4, r4, #1			@ area size *= 2
81	movs	r3, r3, lsr #1
82	bne	1b				@ count not zero r-shift
83	orr	r0, r0, r4, lsl #1		@ the area register value
84	orr	r0, r0, #1			@ set enable bit
85	mcr	p15, 0, r0, c6,	c1		@ set area 1, RAM
86
87	ldr	r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH
88	ldr	r3, =(CONFIG_FLASH_SIZE >> 12)	@ size of FLASH (must be >= 4KB)
89	cmp	r3, #0
90	moveq	r0, #0
91	beq	2f
92	mov	r4, #10				@ 11 is the minimum (4KB)
931:	add	r4, r4, #1			@ area size *= 2
94	movs	r3, r3, lsr #1
95	bne	1b				@ count not zero r-shift
96	orr	r0, r0, r4, lsl #1		@ the area register value
97	orr	r0, r0, #1			@ set enable bit
982:	mcr	p15, 0, r0, c6,	c2		@ set area 2, ROM/FLASH
99
100	mov	r0, #0x06
101	mcr	p15, 0, r0, c2, c0		@ Region 1&2 cacheable
102#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
103	mov	r0, #0x00			@ disable whole write buffer
104#else
105	mov	r0, #0x02			@ Region 1 write bufferred
106#endif
107	mcr	p15, 0, r0, c3, c0
108
109	mov	r0, #0x10000
110	sub	r0, r0, #1			@ r0 = 0xffff
111	mcr	p15, 0, r0, c5, c0		@ all read/write access
112
113	mrc	p15, 0, r0, c1, c0		@ get control register
114	bic	r0, r0, #0x3F000000		@ set to standard caching mode
115						@ need some benchmark
116	orr	r0, r0, #0x0000000d		@ MPU/Cache/WB
117
118	ret	lr
119
120	.size	__arm740_setup, . - __arm740_setup
121
122	__INITDATA
123
124	@ define struct processor (see <asm/proc-fns.h> and proc-macros.S)
125	define_processor_functions arm740, dabort=v4t_late_abort, pabort=legacy_pabort, nommu=1
126
127	.section ".rodata"
128
129	string	cpu_arch_name, "armv4"
130	string	cpu_elf_name, "v4"
131	string	cpu_arm740_name, "ARM740T"
132
133	.align
134
135	.section ".proc.info.init", #alloc, #execinstr
136	.type	__arm740_proc_info,#object
137__arm740_proc_info:
138	.long	0x41807400
139	.long	0xfffffff0
140	.long	0
141	.long	0
142	b	__arm740_setup
143	.long	cpu_arch_name
144	.long	cpu_elf_name
145	.long	HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB | HWCAP_26BIT
146	.long	cpu_arm740_name
147	.long	arm740_processor_functions
148	.long	0
149	.long	0
150	.long	v4_cache_fns			@ cache model
151	.size	__arm740_proc_info, . - __arm740_proc_info
152