2 * linux/arch/arm/mm/proc-v6.S
4 * Copyright (C) 2001 Deep Blue Solutions Ltd.
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.
10 * This is the "shell" of the ARMv6 processor support.
12 #include <linux/linkage.h>
13 #include <asm/assembler.h>
14 #include <asm/asm-offsets.h>
15 #include <asm/procinfo.h>
16 #include <asm/pgtable.h>
18 #include "proc-macros.S"
20 #define D_CACHE_LINE_SIZE 32
54 ENTRY(cpu_v6_proc_init)
57 ENTRY(cpu_v6_proc_fin)
59 cpsid if @ disable interrupts
60 bl v6_flush_kern_cache_all
61 mrc p15, 0, r0, c1, c0, 0 @ ctrl register
62 bic r0, r0, #0x1000 @ ...i............
63 bic r0, r0, #0x0006 @ .............ca.
64 mcr p15, 0, r0, c1, c0, 0 @ disable caches
70 * Perform a soft reset of the system. Put the CPU into the
71 * same state as it would be if it had been reset, and branch
72 * to what would be the reset vector.
74 * - loc - location to jump to for soft reset
85 * Idle the processor (eg, wait for interrupt).
87 * IRQs are already disabled.
90 mcr p15, 0, r1, c7, c0, 4 @ wait for interrupt
93 ENTRY(cpu_v6_dcache_clean_area)
94 #ifndef TLB_CAN_READ_FROM_L1_CACHE
95 1: mcr p15, 0, r0, c7, c10, 1 @ clean D entry
96 add r0, r0, #D_CACHE_LINE_SIZE
97 subs r1, r1, #D_CACHE_LINE_SIZE
103 * cpu_arm926_switch_mm(pgd_phys, tsk)
105 * Set the translation table base pointer to be pgd_phys
107 * - pgd_phys - physical address of new TTB
109 * It is assumed that:
110 * - we are not using split page tables
112 ENTRY(cpu_v6_switch_mm)
114 ldr r1, [r1, #MM_CONTEXT_ID] @ get mm->context.id
116 orr r0, r0, #2 @ set shared pgtable
118 mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
119 mcr p15, 0, r2, c7, c10, 4 @ drain write buffer
120 mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
121 mcr p15, 0, r1, c13, c0, 1 @ set context ID
125 * cpu_v6_set_pte(ptep, pte)
127 * Set a level 2 translation table entry.
129 * - ptep - pointer to level 2 translation table entry
130 * (hardware version is stored at -1024 bytes)
131 * - pte - PTE value to store
134 * YUWD APX AP1 AP0 SVC User
135 * 0xxx 0 0 0 no acc no acc
136 * 100x 1 0 1 r/o no acc
137 * 10x0 1 0 1 r/o no acc
138 * 1011 0 0 1 r/w no acc
143 ENTRY(cpu_v6_set_pte)
144 str r1, [r0], #-2048 @ linux version
146 bic r2, r1, #0x000003f0
147 bic r2, r2, #0x00000003
148 orr r2, r2, #PTE_EXT_AP0 | 2
151 tstne r1, #L_PTE_DIRTY
152 orreq r2, r2, #PTE_EXT_APX
155 orrne r2, r2, #PTE_EXT_AP1
156 tstne r2, #PTE_EXT_APX
157 bicne r2, r2, #PTE_EXT_APX | PTE_EXT_AP0
160 biceq r2, r2, #PTE_EXT_APX | PTE_EXT_AP_MASK
162 @ tst r1, #L_PTE_EXEC
163 @ orreq r2, r2, #PTE_EXT_XN
165 tst r1, #L_PTE_PRESENT
169 mcr p15, 0, r0, c7, c10, 1 @ flush_pte
176 .asciz "Some Random V6 Processor"
179 .section ".text.init", #alloc, #execinstr
184 * Initialise TLB, Caches, and MMU state ready to switch the MMU
185 * on. Return in r0 the new CP15 C1 control register setting.
187 * We automatically detect if we have a Harvard cache, and use the
188 * Harvard cache control instructions insead of the unified cache
189 * control instructions.
191 * This should be able to cover all ARMv6 cores.
193 * It is assumed that:
194 * - cache type register is implemented
198 mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache
199 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
200 mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache
201 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
202 mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs
203 mcr p15, 0, r0, c2, c0, 2 @ TTB control register
205 orr r4, r4, #2 @ set shared pgtable
207 mcr p15, 0, r4, c2, c0, 1 @ load TTB1
209 mrc p15, 0, r0, c1, c0, 2
210 orr r0, r0, #(0xf << 20)
211 mcr p15, 0, r0, c1, c0, 2 @ Enable full access to VFP
213 mrc p15, 0, r0, c1, c0, 0 @ read control register
214 ldr r5, v6_cr1_clear @ get mask for bits to clear
215 bic r0, r0, r5 @ clear bits them
216 ldr r5, v6_cr1_set @ get mask for bits to set
217 orr r0, r0, r5 @ set them
218 mov pc, lr @ return to head.S:__ret
222 * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
223 * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
224 * 0 110 0011 1.00 .111 1101 < we want
226 .type v6_cr1_clear, #object
227 .type v6_cr1_set, #object
233 .type v6_processor_functions, #object
234 ENTRY(v6_processor_functions)
236 .word cpu_v6_proc_init
237 .word cpu_v6_proc_fin
240 .word cpu_v6_dcache_clean_area
241 .word cpu_v6_switch_mm
243 .size v6_processor_functions, . - v6_processor_functions
245 .type cpu_arch_name, #object
248 .size cpu_arch_name, . - cpu_arch_name
250 .type cpu_elf_name, #object
253 .size cpu_elf_name, . - cpu_elf_name
256 .section ".proc.info.init", #alloc, #execinstr
259 * Match any ARMv6 processor core.
261 .type __v6_proc_info, #object
265 .long PMD_TYPE_SECT | \
266 PMD_SECT_BUFFERABLE | \
267 PMD_SECT_CACHEABLE | \
268 PMD_SECT_AP_WRITE | \
273 .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_VFP|HWCAP_EDSP|HWCAP_JAVA
275 .long v6_processor_functions
279 .size __v6_proc_info, . - __v6_proc_info