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authorChris Dearman <chris@mips.com>2007-09-13 07:32:02 -0400
committerRalf Baechle <ralf@linux-mips.org>2008-04-28 12:14:23 -0400
commit0b6d497fcbb72b356c9d6446810a9597ee55c432 (patch)
tree73460a333895a5b9b382fcd5bd13c235234514a9
parentfb2a27e743cd565c25cd896911e494482a8b7251 (diff)
[MIPS] Basic SPRAM support
Signed-off-by: Chris Dearman <chris@mips.com> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
-rw-r--r--arch/mips/kernel/Makefile1
-rw-r--r--arch/mips/kernel/cpu-probe.c8
-rw-r--r--arch/mips/kernel/spram.c221
3 files changed, 230 insertions, 0 deletions
diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile
index 6fcdb6fda2e2..67d97fb02c38 100644
--- a/arch/mips/kernel/Makefile
+++ b/arch/mips/kernel/Makefile
@@ -50,6 +50,7 @@ obj-$(CONFIG_MIPS_MT) += mips-mt.o
50obj-$(CONFIG_MIPS_MT_FPAFF) += mips-mt-fpaff.o 50obj-$(CONFIG_MIPS_MT_FPAFF) += mips-mt-fpaff.o
51obj-$(CONFIG_MIPS_MT_SMTC) += smtc.o smtc-asm.o smtc-proc.o 51obj-$(CONFIG_MIPS_MT_SMTC) += smtc.o smtc-asm.o smtc-proc.o
52obj-$(CONFIG_MIPS_MT_SMP) += smp-mt.o 52obj-$(CONFIG_MIPS_MT_SMP) += smp-mt.o
53obj-$(CONFIG_CPU_MIPSR2) += spram.o
53 54
54obj-$(CONFIG_MIPS_APSP_KSPD) += kspd.o 55obj-$(CONFIG_MIPS_APSP_KSPD) += kspd.o
55obj-$(CONFIG_MIPS_VPE_LOADER) += vpe.o 56obj-$(CONFIG_MIPS_VPE_LOADER) += vpe.o
diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
index 89c3304cb93c..add717dccf77 100644
--- a/arch/mips/kernel/cpu-probe.c
+++ b/arch/mips/kernel/cpu-probe.c
@@ -675,6 +675,12 @@ static void __cpuinit decode_configs(struct cpuinfo_mips *c)
675 return; 675 return;
676} 676}
677 677
678#ifdef CONFIG_CPU_MIPSR2
679extern void spram_config(void);
680#else
681static inline void spram_config(void) {}
682#endif
683
678static inline void cpu_probe_mips(struct cpuinfo_mips *c) 684static inline void cpu_probe_mips(struct cpuinfo_mips *c)
679{ 685{
680 decode_configs(c); 686 decode_configs(c);
@@ -712,6 +718,8 @@ static inline void cpu_probe_mips(struct cpuinfo_mips *c)
712 c->cputype = CPU_74K; 718 c->cputype = CPU_74K;
713 break; 719 break;
714 } 720 }
721
722 spram_config();
715} 723}
716 724
717static inline void cpu_probe_alchemy(struct cpuinfo_mips *c) 725static inline void cpu_probe_alchemy(struct cpuinfo_mips *c)
diff --git a/arch/mips/kernel/spram.c b/arch/mips/kernel/spram.c
new file mode 100644
index 000000000000..6ddb507a87ef
--- /dev/null
+++ b/arch/mips/kernel/spram.c
@@ -0,0 +1,221 @@
1/*
2 * MIPS SPRAM support
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Copyright (C) 2007, 2008 MIPS Technologies, Inc.
10 */
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/ptrace.h>
14#include <linux/stddef.h>
15
16#include <asm/cpu.h>
17#include <asm/fpu.h>
18#include <asm/mipsregs.h>
19#include <asm/system.h>
20#include <asm/r4kcache.h>
21#include <asm/hazards.h>
22
23/*
24 * These definitions are correct for the 24K/34K/74K SPRAM sample
25 * implementation. The 4KS interpreted the tags differently...
26 */
27#define SPRAM_TAG0_ENABLE 0x00000080
28#define SPRAM_TAG0_PA_MASK 0xfffff000
29#define SPRAM_TAG1_SIZE_MASK 0xfffff000
30
31#define SPRAM_TAG_STRIDE 8
32
33#define ERRCTL_SPRAM (1 << 28)
34
35/* errctl access */
36#define read_c0_errctl(x) read_c0_ecc(x)
37#define write_c0_errctl(x) write_c0_ecc(x)
38
39/*
40 * Different semantics to the set_c0_* function built by __BUILD_SET_C0
41 */
42static __cpuinit unsigned int bis_c0_errctl(unsigned int set)
43{
44 unsigned int res;
45 res = read_c0_errctl();
46 write_c0_errctl(res | set);
47 return res;
48}
49
50static __cpuinit void ispram_store_tag(unsigned int offset, unsigned int data)
51{
52 unsigned int errctl;
53
54 /* enable SPRAM tag access */
55 errctl = bis_c0_errctl(ERRCTL_SPRAM);
56 ehb();
57
58 write_c0_taglo(data);
59 ehb();
60
61 cache_op(Index_Store_Tag_I, CKSEG0|offset);
62 ehb();
63
64 write_c0_errctl(errctl);
65 ehb();
66}
67
68
69static __cpuinit unsigned int ispram_load_tag(unsigned int offset)
70{
71 unsigned int data;
72 unsigned int errctl;
73
74 /* enable SPRAM tag access */
75 errctl = bis_c0_errctl(ERRCTL_SPRAM);
76 ehb();
77 cache_op(Index_Load_Tag_I, CKSEG0 | offset);
78 ehb();
79 data = read_c0_taglo();
80 ehb();
81 write_c0_errctl(errctl);
82 ehb();
83
84 return data;
85}
86
87static __cpuinit void dspram_store_tag(unsigned int offset, unsigned int data)
88{
89 unsigned int errctl;
90
91 /* enable SPRAM tag access */
92 errctl = bis_c0_errctl(ERRCTL_SPRAM);
93 ehb();
94 write_c0_dtaglo(data);
95 ehb();
96 cache_op(Index_Store_Tag_D, CKSEG0 | offset);
97 ehb();
98 write_c0_errctl(errctl);
99 ehb();
100}
101
102
103static __cpuinit unsigned int dspram_load_tag(unsigned int offset)
104{
105 unsigned int data;
106 unsigned int errctl;
107
108 errctl = bis_c0_errctl(ERRCTL_SPRAM);
109 ehb();
110 cache_op(Index_Load_Tag_D, CKSEG0 | offset);
111 ehb();
112 data = read_c0_dtaglo();
113 ehb();
114 write_c0_errctl(errctl);
115 ehb();
116
117 return data;
118}
119
120static __cpuinit void probe_spram(char *type,
121 unsigned int base,
122 unsigned int (*read)(unsigned int),
123 void (*write)(unsigned int, unsigned int))
124{
125 unsigned int firstsize = 0, lastsize = 0;
126 unsigned int firstpa = 0, lastpa = 0, pa = 0;
127 unsigned int offset = 0;
128 unsigned int size, tag0, tag1;
129 unsigned int enabled;
130 int i;
131
132 /*
133 * The limit is arbitrary but avoids the loop running away if
134 * the SPRAM tags are implemented differently
135 */
136
137 for (i = 0; i < 8; i++) {
138 tag0 = read(offset);
139 tag1 = read(offset+SPRAM_TAG_STRIDE);
140 pr_debug("DBG %s%d: tag0=%08x tag1=%08x\n",
141 type, i, tag0, tag1);
142
143 size = tag1 & SPRAM_TAG1_SIZE_MASK;
144
145 if (size == 0)
146 break;
147
148 if (i != 0) {
149 /* tags may repeat... */
150 if ((pa == firstpa && size == firstsize) ||
151 (pa == lastpa && size == lastsize))
152 break;
153 }
154
155 /* Align base with size */
156 base = (base + size - 1) & ~(size-1);
157
158 /* reprogram the base address base address and enable */
159 tag0 = (base & SPRAM_TAG0_PA_MASK) | SPRAM_TAG0_ENABLE;
160 write(offset, tag0);
161
162 base += size;
163
164 /* reread the tag */
165 tag0 = read(offset);
166 pa = tag0 & SPRAM_TAG0_PA_MASK;
167 enabled = tag0 & SPRAM_TAG0_ENABLE;
168
169 if (i == 0) {
170 firstpa = pa;
171 firstsize = size;
172 }
173
174 lastpa = pa;
175 lastsize = size;
176
177 if (strcmp(type, "DSPRAM") == 0) {
178 unsigned int *vp = (unsigned int *)(CKSEG1 | pa);
179 unsigned int v;
180#define TDAT 0x5a5aa5a5
181 vp[0] = TDAT;
182 vp[1] = ~TDAT;
183
184 mb();
185
186 v = vp[0];
187 if (v != TDAT)
188 printk(KERN_ERR "vp=%p wrote=%08x got=%08x\n",
189 vp, TDAT, v);
190 v = vp[1];
191 if (v != ~TDAT)
192 printk(KERN_ERR "vp=%p wrote=%08x got=%08x\n",
193 vp+1, ~TDAT, v);
194 }
195
196 pr_info("%s%d: PA=%08x,Size=%08x%s\n",
197 type, i, pa, size, enabled ? ",enabled" : "");
198 offset += 2 * SPRAM_TAG_STRIDE;
199 }
200}
201
202__cpuinit void spram_config(void)
203{
204 struct cpuinfo_mips *c = &current_cpu_data;
205 unsigned int config0;
206
207 switch (c->cputype) {
208 case CPU_24K:
209 case CPU_34K:
210 case CPU_74K:
211 config0 = read_c0_config();
212 /* FIXME: addresses are Malta specific */
213 if (config0 & (1<<24)) {
214 probe_spram("ISPRAM", 0x1c000000,
215 &ispram_load_tag, &ispram_store_tag);
216 }
217 if (config0 & (1<<23))
218 probe_spram("DSPRAM", 0x1c100000,
219 &dspram_load_tag, &dspram_store_tag);
220 }
221}