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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/frv/kernel/cmode.S
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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diff --git a/arch/frv/kernel/cmode.S b/arch/frv/kernel/cmode.S
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1/* cmode.S: clock mode management
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Woodhouse (dwmw2@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 *
11 */
12
13#include <linux/sys.h>
14#include <linux/config.h>
15#include <linux/linkage.h>
16#include <asm/setup.h>
17#include <asm/segment.h>
18#include <asm/ptrace.h>
19#include <asm/errno.h>
20#include <asm/cache.h>
21#include <asm/spr-regs.h>
22
23#define __addr_MASK 0xfeff9820 /* interrupt controller mask */
24
25#define __addr_SDRAMC 0xfe000400 /* SDRAM controller regs */
26#define SDRAMC_DSTS 0x28 /* SDRAM status */
27#define SDRAMC_DSTS_SSI 0x00000001 /* indicates that the SDRAM is in self-refresh mode */
28#define SDRAMC_DRCN 0x30 /* SDRAM refresh control */
29#define SDRAMC_DRCN_SR 0x00000001 /* transition SDRAM into self-refresh mode */
30#define __addr_CLKC 0xfeff9a00
31#define CLKC_SWCMODE 0x00000008
32#define __addr_LEDS 0xe1200004
33
34.macro li v r
35 sethi.p %hi(\v),\r
36 setlo %lo(\v),\r
37.endm
38
39 .text
40 .balign 4
41
42
43###############################################################################
44#
45# Change CMODE
46# - void frv_change_cmode(int cmode)
47#
48###############################################################################
49 .globl frv_change_cmode
50 .type frv_change_cmode,@function
51
52.macro LEDS v
53#ifdef DEBUG_CMODE
54 setlos #~\v,gr10
55 sti gr10,@(gr11,#0)
56 membar
57#endif
58.endm
59
60frv_change_cmode:
61 movsg lr,gr9
62#ifdef DEBUG_CMODE
63 li __addr_LEDS,gr11
64#endif
65 dcef @(gr0,gr0),#1
66
67 # Shift argument left by 24 bits to fit in SWCMODE register later.
68 slli gr8,#24,gr8
69
70 # (1) Set '0' in the PSR.ET bit, and prohibit interrupts.
71 movsg psr,gr14
72 andi gr14,#~PSR_ET,gr3
73 movgs gr3,psr
74
75#if 0 // Fujitsu recommend to skip this and will update docs.
76 # (2) Set '0' to all bits of the MASK register of the interrupt
77 # controller, and mask interrupts.
78 li __addr_MASK,gr12
79 ldi @(gr12,#0),gr13
80 li 0xffff0000,gr4
81 sti gr4,@(gr12,#0)
82#endif
83
84 # (3) Stop the transfer function of DMAC. Stop all the bus masters
85 # to access SDRAM and the internal resources.
86
87 # (already done by caller)
88
89 # (4) Preload a series of following instructions to the instruction
90 # cache.
91 li #__cmode_icache_lock_start,gr3
92 li #__cmode_icache_lock_end,gr4
93
941: icpl gr3,gr0,#1
95 addi gr3,#L1_CACHE_BYTES,gr3
96 cmp gr4,gr3,icc0
97 bhi icc0,#0,1b
98
99 # Set up addresses in regs for later steps.
100 setlos SDRAMC_DRCN_SR,gr3
101 li __addr_SDRAMC,gr4
102 li __addr_CLKC,gr5
103 ldi @(gr5,#0),gr6
104 li #0x80000000,gr7
105 or gr6,gr7,gr6
106
107 bra __cmode_icache_lock_start
108
109 .balign L1_CACHE_BYTES
110__cmode_icache_lock_start:
111
112 # (5) Flush the content of all caches by the DCEF instruction.
113 dcef @(gr0,gr0),#1
114
115 # (6) Execute loading the dummy for SDRAM.
116 ldi @(gr9,#0),gr0
117
118 # (7) Set '1' to the DRCN.SR bit, and change SDRAM to the
119 # self-refresh mode. Execute the dummy load to all memory
120 # devices set to cacheable on the external bus side in parallel
121 # with this.
122 sti gr3,@(gr4,#SDRAMC_DRCN)
123
124 # (8) Execute memory barrier instruction (MEMBAR).
125 membar
126
127 # (9) Read the DSTS register repeatedly until '1' stands in the
128 # DSTS.SSI field.
1291: ldi @(gr4,#SDRAMC_DSTS),gr3
130 andicc gr3,#SDRAMC_DSTS_SSI,gr3,icc0
131 beq icc0,#0,1b
132
133 # (10) Execute memory barrier instruction (MEMBAR).
134 membar
135
136#if 1
137 # (11) Set the value of CMODE that you want to change to
138 # SWCMODE.SWCM[3:0].
139 sti gr8,@(gr5,#CLKC_SWCMODE)
140
141 # (12) Set '1' to the CLKC.SWEN bit. In that case, do not change
142 # fields other than SWEN of the CLKC register.
143 sti gr6,@(gr5,#0)
144#endif
145 # (13) Execute the instruction just after the memory barrier
146 # instruction that executes the self-loop 256 times. (Meanwhile,
147 # the CMODE switch is done.)
148 membar
149 setlos #256,gr7
1502: subicc gr7,#1,gr7,icc0
151 bne icc0,#2,2b
152
153 LEDS 0x36
154
155 # (14) Release the self-refresh of SDRAM.
156 sti gr0,@(gr4,#SDRAMC_DRCN)
157
158 # Wait for it...
1593: ldi @(gr4,#SDRAMC_DSTS),gr3
160 andicc gr3,#SDRAMC_DSTS_SSI,gr3,icc0
161 bne icc0,#2,3b
162
163#if 0
164 li 0x0100000,gr10
1654: subicc gr10,#1,gr10,icc0
166
167 bne icc0,#0,4b
168#endif
169
170__cmode_icache_lock_end:
171
172 li #__cmode_icache_lock_start,gr3
173 li #__cmode_icache_lock_end,gr4
174
1754: icul gr3
176 addi gr3,#L1_CACHE_BYTES,gr3
177 cmp gr4,gr3,icc0
178 bhi icc0,#0,4b
179
180#if 0 // Fujitsu recommend to skip this and will update docs.
181 # (15) Release the interrupt mask setting of the MASK register of
182 # the interrupt controller if necessary.
183 sti gr13,@(gr12,#0)
184#endif
185 # (16) Set 1' in the PSR.ET bit, and permit interrupt.
186 movgs gr14,psr
187
188 bralr
189
190 .size frv_change_cmode, .-frv_change_cmode