diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh64/kernel/head.S |
Linux-2.6.12-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!
Diffstat (limited to 'arch/sh64/kernel/head.S')
-rw-r--r-- | arch/sh64/kernel/head.S | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/arch/sh64/kernel/head.S b/arch/sh64/kernel/head.S new file mode 100644 index 000000000000..cc0b628a9ea7 --- /dev/null +++ b/arch/sh64/kernel/head.S | |||
@@ -0,0 +1,373 @@ | |||
1 | /* | ||
2 | * This file is subject to the terms and conditions of the GNU General Public | ||
3 | * License. See the file "COPYING" in the main directory of this archive | ||
4 | * for more details. | ||
5 | * | ||
6 | * arch/sh64/kernel/head.S | ||
7 | * | ||
8 | * Copyright (C) 2000, 2001 Paolo Alberelli | ||
9 | * Copyright (C) 2003, 2004 Paul Mundt | ||
10 | * | ||
11 | * | ||
12 | * benedict.gaster@superh.com: 2nd May 2002 | ||
13 | * Moved definition of empty_zero_page to its own section allowing | ||
14 | * it to be placed at an absolute address known at load time. | ||
15 | * | ||
16 | * lethal@linux-sh.org: 9th May 2003 | ||
17 | * Kill off GLOBAL_NAME() usage. | ||
18 | * | ||
19 | * lethal@linux-sh.org: 8th May 2004 | ||
20 | * Add early SCIF console DTLB mapping. | ||
21 | */ | ||
22 | |||
23 | #include <linux/config.h> | ||
24 | |||
25 | #include <asm/page.h> | ||
26 | #include <asm/mmu_context.h> | ||
27 | #include <asm/cache.h> | ||
28 | #include <asm/tlb.h> | ||
29 | #include <asm/processor.h> | ||
30 | #include <asm/registers.h> | ||
31 | #include <asm/thread_info.h> | ||
32 | |||
33 | /* | ||
34 | * MMU defines: TLB boundaries. | ||
35 | */ | ||
36 | |||
37 | #define MMUIR_FIRST ITLB_FIXED | ||
38 | #define MMUIR_END ITLB_LAST_VAR_UNRESTRICTED+TLB_STEP | ||
39 | #define MMUIR_STEP TLB_STEP | ||
40 | |||
41 | #define MMUDR_FIRST DTLB_FIXED | ||
42 | #define MMUDR_END DTLB_LAST_VAR_UNRESTRICTED+TLB_STEP | ||
43 | #define MMUDR_STEP TLB_STEP | ||
44 | |||
45 | /* Safety check : CONFIG_CACHED_MEMORY_OFFSET has to be a multiple of 512Mb */ | ||
46 | #if (CONFIG_CACHED_MEMORY_OFFSET & ((1UL<<29)-1)) | ||
47 | #error "CONFIG_CACHED_MEMORY_OFFSET must be a multiple of 512Mb" | ||
48 | #endif | ||
49 | |||
50 | /* | ||
51 | * MMU defines: Fixed TLBs. | ||
52 | */ | ||
53 | /* Deal safely with the case where the base of RAM is not 512Mb aligned */ | ||
54 | |||
55 | #define ALIGN_512M_MASK (0xffffffffe0000000) | ||
56 | #define ALIGNED_EFFECTIVE ((CONFIG_CACHED_MEMORY_OFFSET + CONFIG_MEMORY_START) & ALIGN_512M_MASK) | ||
57 | #define ALIGNED_PHYSICAL (CONFIG_MEMORY_START & ALIGN_512M_MASK) | ||
58 | |||
59 | #define MMUIR_TEXT_H (0x0000000000000003 | ALIGNED_EFFECTIVE) | ||
60 | /* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */ | ||
61 | |||
62 | #define MMUIR_TEXT_L (0x000000000000009a | ALIGNED_PHYSICAL) | ||
63 | /* 512 Mb, Cacheable, Write-back, execute, Not User, Ph. Add. */ | ||
64 | |||
65 | #define MMUDR_CACHED_H 0x0000000000000003 | ALIGNED_EFFECTIVE | ||
66 | /* Enabled, Shared, ASID 0, Eff. Add. 0xA0000000 */ | ||
67 | #define MMUDR_CACHED_L 0x000000000000015a | ALIGNED_PHYSICAL | ||
68 | /* 512 Mb, Cacheable, Write-back, read/write, Not User, Ph. Add. */ | ||
69 | |||
70 | #ifdef CONFIG_ICACHE_DISABLED | ||
71 | #define ICCR0_INIT_VAL ICCR0_OFF /* ICACHE off */ | ||
72 | #else | ||
73 | #define ICCR0_INIT_VAL ICCR0_ON | ICCR0_ICI /* ICE + ICI */ | ||
74 | #endif | ||
75 | #define ICCR1_INIT_VAL ICCR1_NOLOCK /* No locking */ | ||
76 | |||
77 | #if defined (CONFIG_DCACHE_DISABLED) | ||
78 | #define OCCR0_INIT_VAL OCCR0_OFF /* D-cache: off */ | ||
79 | #elif defined (CONFIG_DCACHE_WRITE_THROUGH) | ||
80 | #define OCCR0_INIT_VAL OCCR0_ON | OCCR0_OCI | OCCR0_WT /* D-cache: on, */ | ||
81 | /* WT, invalidate */ | ||
82 | #elif defined (CONFIG_DCACHE_WRITE_BACK) | ||
83 | #define OCCR0_INIT_VAL OCCR0_ON | OCCR0_OCI | OCCR0_WB /* D-cache: on, */ | ||
84 | /* WB, invalidate */ | ||
85 | #else | ||
86 | #error preprocessor flag CONFIG_DCACHE_... not recognized! | ||
87 | #endif | ||
88 | |||
89 | #define OCCR1_INIT_VAL OCCR1_NOLOCK /* No locking */ | ||
90 | |||
91 | .section .empty_zero_page, "aw" | ||
92 | .global empty_zero_page | ||
93 | |||
94 | empty_zero_page: | ||
95 | .long 1 /* MOUNT_ROOT_RDONLY */ | ||
96 | .long 0 /* RAMDISK_FLAGS */ | ||
97 | .long 0x0200 /* ORIG_ROOT_DEV */ | ||
98 | .long 1 /* LOADER_TYPE */ | ||
99 | .long 0x00800000 /* INITRD_START */ | ||
100 | .long 0x00800000 /* INITRD_SIZE */ | ||
101 | .long 0 | ||
102 | |||
103 | .text | ||
104 | .balign 4096,0,4096 | ||
105 | |||
106 | .section .data, "aw" | ||
107 | .balign PAGE_SIZE | ||
108 | |||
109 | .section .data, "aw" | ||
110 | .balign PAGE_SIZE | ||
111 | |||
112 | .global swapper_pg_dir | ||
113 | swapper_pg_dir: | ||
114 | .space PAGE_SIZE, 0 | ||
115 | |||
116 | .global empty_bad_page | ||
117 | empty_bad_page: | ||
118 | .space PAGE_SIZE, 0 | ||
119 | |||
120 | .global empty_bad_pte_table | ||
121 | empty_bad_pte_table: | ||
122 | .space PAGE_SIZE, 0 | ||
123 | |||
124 | .global fpu_in_use | ||
125 | fpu_in_use: .quad 0 | ||
126 | |||
127 | |||
128 | .section .text, "ax" | ||
129 | .balign L1_CACHE_BYTES | ||
130 | /* | ||
131 | * Condition at the entry of __stext: | ||
132 | * . Reset state: | ||
133 | * . SR.FD = 1 (FPU disabled) | ||
134 | * . SR.BL = 1 (Exceptions disabled) | ||
135 | * . SR.MD = 1 (Privileged Mode) | ||
136 | * . SR.MMU = 0 (MMU Disabled) | ||
137 | * . SR.CD = 0 (CTC User Visible) | ||
138 | * . SR.IMASK = Undefined (Interrupt Mask) | ||
139 | * | ||
140 | * Operations supposed to be performed by __stext: | ||
141 | * . prevent speculative fetch onto device memory while MMU is off | ||
142 | * . reflect as much as possible SH5 ABI (r15, r26, r27, r18) | ||
143 | * . first, save CPU state and set it to something harmless | ||
144 | * . any CPU detection and/or endianness settings (?) | ||
145 | * . initialize EMI/LMI (but not TMU/RTC/INTC/SCIF): TBD | ||
146 | * . set initial TLB entries for cached and uncached regions | ||
147 | * (no fine granularity paging) | ||
148 | * . set initial cache state | ||
149 | * . enable MMU and caches | ||
150 | * . set CPU to a consistent state | ||
151 | * . registers (including stack pointer and current/KCR0) | ||
152 | * . NOT expecting to set Exception handling nor VBR/RESVEC/DCR | ||
153 | * at this stage. This is all to later Linux initialization steps. | ||
154 | * . initialize FPU | ||
155 | * . clear BSS | ||
156 | * . jump into start_kernel() | ||
157 | * . be prepared to hopeless start_kernel() returns. | ||
158 | * | ||
159 | */ | ||
160 | .global _stext | ||
161 | _stext: | ||
162 | /* | ||
163 | * Prevent speculative fetch on device memory due to | ||
164 | * uninitialized target registers. | ||
165 | */ | ||
166 | ptabs/u ZERO, tr0 | ||
167 | ptabs/u ZERO, tr1 | ||
168 | ptabs/u ZERO, tr2 | ||
169 | ptabs/u ZERO, tr3 | ||
170 | ptabs/u ZERO, tr4 | ||
171 | ptabs/u ZERO, tr5 | ||
172 | ptabs/u ZERO, tr6 | ||
173 | ptabs/u ZERO, tr7 | ||
174 | synci | ||
175 | |||
176 | /* | ||
177 | * Read/Set CPU state. After this block: | ||
178 | * r29 = Initial SR | ||
179 | */ | ||
180 | getcon SR, r29 | ||
181 | movi SR_HARMLESS, r20 | ||
182 | putcon r20, SR | ||
183 | |||
184 | /* | ||
185 | * Initialize EMI/LMI. To Be Done. | ||
186 | */ | ||
187 | |||
188 | /* | ||
189 | * CPU detection and/or endianness settings (?). To Be Done. | ||
190 | * Pure PIC code here, please ! Just save state into r30. | ||
191 | * After this block: | ||
192 | * r30 = CPU type/Platform Endianness | ||
193 | */ | ||
194 | |||
195 | /* | ||
196 | * Set initial TLB entries for cached and uncached regions. | ||
197 | * Note: PTA/BLINK is PIC code, PTABS/BLINK isn't ! | ||
198 | */ | ||
199 | /* Clear ITLBs */ | ||
200 | pta clear_ITLB, tr1 | ||
201 | movi MMUIR_FIRST, r21 | ||
202 | movi MMUIR_END, r22 | ||
203 | clear_ITLB: | ||
204 | putcfg r21, 0, ZERO /* Clear MMUIR[n].PTEH.V */ | ||
205 | addi r21, MMUIR_STEP, r21 | ||
206 | bne r21, r22, tr1 | ||
207 | |||
208 | /* Clear DTLBs */ | ||
209 | pta clear_DTLB, tr1 | ||
210 | movi MMUDR_FIRST, r21 | ||
211 | movi MMUDR_END, r22 | ||
212 | clear_DTLB: | ||
213 | putcfg r21, 0, ZERO /* Clear MMUDR[n].PTEH.V */ | ||
214 | addi r21, MMUDR_STEP, r21 | ||
215 | bne r21, r22, tr1 | ||
216 | |||
217 | /* Map one big (512Mb) page for ITLB */ | ||
218 | movi MMUIR_FIRST, r21 | ||
219 | movi MMUIR_TEXT_L, r22 /* PTEL first */ | ||
220 | add.l r22, r63, r22 /* Sign extend */ | ||
221 | putcfg r21, 1, r22 /* Set MMUIR[0].PTEL */ | ||
222 | movi MMUIR_TEXT_H, r22 /* PTEH last */ | ||
223 | add.l r22, r63, r22 /* Sign extend */ | ||
224 | putcfg r21, 0, r22 /* Set MMUIR[0].PTEH */ | ||
225 | |||
226 | /* Map one big CACHED (512Mb) page for DTLB */ | ||
227 | movi MMUDR_FIRST, r21 | ||
228 | movi MMUDR_CACHED_L, r22 /* PTEL first */ | ||
229 | add.l r22, r63, r22 /* Sign extend */ | ||
230 | putcfg r21, 1, r22 /* Set MMUDR[0].PTEL */ | ||
231 | movi MMUDR_CACHED_H, r22 /* PTEH last */ | ||
232 | add.l r22, r63, r22 /* Sign extend */ | ||
233 | putcfg r21, 0, r22 /* Set MMUDR[0].PTEH */ | ||
234 | |||
235 | #ifdef CONFIG_EARLY_PRINTK | ||
236 | /* | ||
237 | * Setup a DTLB translation for SCIF phys. | ||
238 | */ | ||
239 | addi r21, MMUDR_STEP, r21 | ||
240 | movi 0x0a03, r22 /* SCIF phys */ | ||
241 | shori 0x0148, r22 | ||
242 | putcfg r21, 1, r22 /* PTEL first */ | ||
243 | movi 0xfa03, r22 /* 0xfa030000, fixed SCIF virt */ | ||
244 | shori 0x0003, r22 | ||
245 | putcfg r21, 0, r22 /* PTEH last */ | ||
246 | #endif | ||
247 | |||
248 | /* | ||
249 | * Set cache behaviours. | ||
250 | */ | ||
251 | /* ICache */ | ||
252 | movi ICCR_BASE, r21 | ||
253 | movi ICCR0_INIT_VAL, r22 | ||
254 | movi ICCR1_INIT_VAL, r23 | ||
255 | putcfg r21, ICCR_REG0, r22 | ||
256 | putcfg r21, ICCR_REG1, r23 | ||
257 | |||
258 | /* OCache */ | ||
259 | movi OCCR_BASE, r21 | ||
260 | movi OCCR0_INIT_VAL, r22 | ||
261 | movi OCCR1_INIT_VAL, r23 | ||
262 | putcfg r21, OCCR_REG0, r22 | ||
263 | putcfg r21, OCCR_REG1, r23 | ||
264 | |||
265 | |||
266 | /* | ||
267 | * Enable Caches and MMU. Do the first non-PIC jump. | ||
268 | * Now head.S global variables, constants and externs | ||
269 | * can be used. | ||
270 | */ | ||
271 | getcon SR, r21 | ||
272 | movi SR_ENABLE_MMU, r22 | ||
273 | or r21, r22, r21 | ||
274 | putcon r21, SSR | ||
275 | movi hyperspace, r22 | ||
276 | ori r22, 1, r22 /* Make it SHmedia, not required but..*/ | ||
277 | putcon r22, SPC | ||
278 | synco | ||
279 | rte /* And now go into the hyperspace ... */ | ||
280 | hyperspace: /* ... that's the next instruction ! */ | ||
281 | |||
282 | /* | ||
283 | * Set CPU to a consistent state. | ||
284 | * r31 = FPU support flag | ||
285 | * tr0/tr7 in use. Others give a chance to loop somewhere safe | ||
286 | */ | ||
287 | movi start_kernel, r32 | ||
288 | ori r32, 1, r32 | ||
289 | |||
290 | ptabs r32, tr0 /* r32 = _start_kernel address */ | ||
291 | pta/u hopeless, tr1 | ||
292 | pta/u hopeless, tr2 | ||
293 | pta/u hopeless, tr3 | ||
294 | pta/u hopeless, tr4 | ||
295 | pta/u hopeless, tr5 | ||
296 | pta/u hopeless, tr6 | ||
297 | pta/u hopeless, tr7 | ||
298 | gettr tr1, r28 /* r28 = hopeless address */ | ||
299 | |||
300 | /* Set initial stack pointer */ | ||
301 | movi init_thread_union, SP | ||
302 | putcon SP, KCR0 /* Set current to init_task */ | ||
303 | movi THREAD_SIZE, r22 /* Point to the end */ | ||
304 | add SP, r22, SP | ||
305 | |||
306 | /* | ||
307 | * Initialize FPU. | ||
308 | * Keep FPU flag in r31. After this block: | ||
309 | * r31 = FPU flag | ||
310 | */ | ||
311 | movi fpu_in_use, r31 /* Temporary */ | ||
312 | |||
313 | #ifdef CONFIG_SH_FPU | ||
314 | getcon SR, r21 | ||
315 | movi SR_ENABLE_FPU, r22 | ||
316 | and r21, r22, r22 | ||
317 | putcon r22, SR /* Try to enable */ | ||
318 | getcon SR, r22 | ||
319 | xor r21, r22, r21 | ||
320 | shlri r21, 15, r21 /* Supposedly 0/1 */ | ||
321 | st.q r31, 0 , r21 /* Set fpu_in_use */ | ||
322 | #else | ||
323 | movi 0, r21 | ||
324 | st.q r31, 0 , r21 /* Set fpu_in_use */ | ||
325 | #endif | ||
326 | or r21, ZERO, r31 /* Set FPU flag at last */ | ||
327 | |||
328 | #ifndef CONFIG_SH_NO_BSS_INIT | ||
329 | /* Don't clear BSS if running on slow platforms such as an RTL simulation, | ||
330 | remote memory via SHdebug link, etc. For these the memory can be guaranteed | ||
331 | to be all zero on boot anyway. */ | ||
332 | /* | ||
333 | * Clear bss | ||
334 | */ | ||
335 | pta clear_quad, tr1 | ||
336 | movi __bss_start, r22 | ||
337 | movi _end, r23 | ||
338 | clear_quad: | ||
339 | st.q r22, 0, ZERO | ||
340 | addi r22, 8, r22 | ||
341 | bne r22, r23, tr1 /* Both quad aligned, see vmlinux.lds.S */ | ||
342 | #endif | ||
343 | pta/u hopeless, tr1 | ||
344 | |||
345 | /* Say bye to head.S but be prepared to wrongly get back ... */ | ||
346 | blink tr0, LINK | ||
347 | |||
348 | /* If we ever get back here through LINK/tr1-tr7 */ | ||
349 | pta/u hopeless, tr7 | ||
350 | |||
351 | hopeless: | ||
352 | /* | ||
353 | * Something's badly wrong here. Loop endlessly, | ||
354 | * there's nothing more we can do about it. | ||
355 | * | ||
356 | * Note on hopeless: it can be jumped into invariably | ||
357 | * before or after jumping into hyperspace. The only | ||
358 | * requirement is to be PIC called (PTA) before and | ||
359 | * any way (PTA/PTABS) after. According to Virtual | ||
360 | * to Physical mapping a simulator/emulator can easily | ||
361 | * tell where we came here from just looking at hopeless | ||
362 | * (PC) address. | ||
363 | * | ||
364 | * For debugging purposes: | ||
365 | * (r28) hopeless/loop address | ||
366 | * (r29) Original SR | ||
367 | * (r30) CPU type/Platform endianness | ||
368 | * (r31) FPU Support | ||
369 | * (r32) _start_kernel address | ||
370 | */ | ||
371 | blink tr7, ZERO | ||
372 | |||
373 | |||