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
115 mcr p15, 0, r2, c7, c5, 6 @ flush BTAC/BTB
116 mcr p15, 0, r2, c7, c10, 4 @ drain write buffer
117 mcr p15, 0, r0, c2, c0, 0 @ set TTB 0
118 mcr p15, 0, r1, c13, c0, 1 @ set context ID
122 * cpu_v6_set_pte(ptep, pte)
124 * Set a level 2 translation table entry.
126 * - ptep - pointer to level 2 translation table entry
127 * (hardware version is stored at -1024 bytes)
128 * - pte - PTE value to store
131 * YUWD APX AP1 AP0 SVC User
132 * 0xxx 0 0 0 no acc no acc
133 * 100x 1 0 1 r/o no acc
134 * 10x0 1 0 1 r/o no acc
135 * 1011 0 0 1 r/w no acc
140 ENTRY(cpu_v6_set_pte)
141 str r1, [r0], #-2048 @ linux version
143 bic r2, r1, #0x000007f0
144 bic r2, r2, #0x00000003
145 orr r2, r2, #PTE_EXT_AP0 | 2
148 tstne r1, #L_PTE_DIRTY
149 orreq r2, r2, #PTE_EXT_APX
152 orrne r2, r2, #PTE_EXT_AP1
153 tstne r2, #PTE_EXT_APX
154 bicne r2, r2, #PTE_EXT_APX | PTE_EXT_AP0
157 biceq r2, r2, #PTE_EXT_APX | PTE_EXT_AP_MASK
159 @ tst r1, #L_PTE_EXEC
160 @ orreq r2, r2, #PTE_EXT_XN
162 tst r1, #L_PTE_PRESENT
166 mcr p15, 0, r0, c7, c10, 1 @ flush_pte
173 .asciz "Some Random V6 Processor"
176 .section ".text.init", #alloc, #execinstr
181 * Initialise TLB, Caches, and MMU state ready to switch the MMU
182 * on. Return in r0 the new CP15 C1 control register setting.
184 * We automatically detect if we have a Harvard cache, and use the
185 * Harvard cache control instructions insead of the unified cache
186 * control instructions.
188 * This should be able to cover all ARMv6 cores.
190 * It is assumed that:
191 * - cache type register is implemented
195 mcr p15, 0, r0, c7, c14, 0 @ clean+invalidate D cache
196 mcr p15, 0, r0, c7, c5, 0 @ invalidate I cache
197 mcr p15, 0, r0, c7, c15, 0 @ clean+invalidate cache
198 mcr p15, 0, r0, c7, c10, 4 @ drain write buffer
199 mcr p15, 0, r0, c8, c7, 0 @ invalidate I + D TLBs
200 mcr p15, 0, r0, c2, c0, 2 @ TTB control register
201 mcr p15, 0, r4, c2, c0, 1 @ load TTB1
203 mrc p15, 0, r0, c1, c0, 2
204 orr r0, r0, #(0xf << 20)
205 mcr p15, 0, r0, c1, c0, 2 @ Enable full access to VFP
207 mrc p15, 0, r0, c1, c0, 0 @ read control register
208 ldr r5, v6_cr1_clear @ get mask for bits to clear
209 bic r0, r0, r5 @ clear bits them
210 ldr r5, v6_cr1_set @ get mask for bits to set
211 orr r0, r0, r5 @ set them
212 mov pc, lr @ return to head.S:__ret
216 * .... ...E PUI. .T.T 4RVI ZFRS BLDP WCAM
217 * rrrr rrrx xxx0 0101 xxxx xxxx x111 xxxx < forced
218 * 0 110 0011 1.00 .111 1101 < we want
220 .type v6_cr1_clear, #object
221 .type v6_cr1_set, #object
227 .type v6_processor_functions, #object
228 ENTRY(v6_processor_functions)
230 .word cpu_v6_proc_init
231 .word cpu_v6_proc_fin
234 .word cpu_v6_dcache_clean_area
235 .word cpu_v6_switch_mm
237 .size v6_processor_functions, . - v6_processor_functions
239 .type cpu_arch_name, #object
242 .size cpu_arch_name, . - cpu_arch_name
244 .type cpu_elf_name, #object
247 .size cpu_elf_name, . - cpu_elf_name
250 .section ".proc.info.init", #alloc, #execinstr
253 * Match any ARMv6 processor core.
255 .type __v6_proc_info, #object
259 .long PMD_TYPE_SECT | \
260 PMD_SECT_BUFFERABLE | \
261 PMD_SECT_CACHEABLE | \
262 PMD_SECT_AP_WRITE | \
267 .long HWCAP_SWP|HWCAP_HALF|HWCAP_THUMB|HWCAP_FAST_MULT|HWCAP_VFP|HWCAP_EDSP|HWCAP_JAVA
269 .long v6_processor_functions
273 .size __v6_proc_info, . - __v6_proc_info