1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * linux/arch/arm/mm/arm740.S: utility functions for ARM740 4 * 5 * Copyright (C) 2004-2006 Hyok S. Choi (hyok.choi@samsung.com) 6 */ 7 #include <linux/linkage.h> 8 #include <linux/init.h> 9 #include <linux/pgtable.h> 10 #include <asm/assembler.h> 11 #include <asm/asm-offsets.h> 12 #include <asm/hwcap.h> 13 #include <asm/pgtable-hwdef.h> 14 #include <asm/ptrace.h> 15 16 #include "proc-macros.S" 17 18 .text 19 /* 20 * cpu_arm740_proc_init() 21 * cpu_arm740_do_idle() 22 * cpu_arm740_dcache_clean_area() 23 * cpu_arm740_switch_mm() 24 * 25 * These are not required. 26 */ 27 ENTRY(cpu_arm740_proc_init) 28 ENTRY(cpu_arm740_do_idle) 29 ENTRY(cpu_arm740_dcache_clean_area) 30 ENTRY(cpu_arm740_switch_mm) 31 ret lr 32 33 /* 34 * cpu_arm740_proc_fin() 35 */ 36 ENTRY(cpu_arm740_proc_fin) 37 mrc p15, 0, r0, c1, c0, 0 38 bic r0, r0, #0x3f000000 @ bank/f/lock/s 39 bic r0, r0, #0x0000000c @ w-buffer/cache 40 mcr p15, 0, r0, c1, c0, 0 @ disable caches 41 ret lr 42 43 /* 44 * cpu_arm740_reset(loc) 45 * Params : r0 = address to jump to 46 * Notes : This sets up everything for a reset 47 */ 48 .pushsection .idmap.text, "ax" 49 ENTRY(cpu_arm740_reset) 50 mov ip, #0 51 mcr p15, 0, ip, c7, c0, 0 @ invalidate cache 52 mrc p15, 0, ip, c1, c0, 0 @ get ctrl register 53 bic ip, ip, #0x0000000c @ ............wc.. 54 mcr p15, 0, ip, c1, c0, 0 @ ctrl register 55 ret r0 56 ENDPROC(cpu_arm740_reset) 57 .popsection 58 59 .type __arm740_setup, #function 60 __arm740_setup: 61 mov r0, #0 62 mcr p15, 0, r0, c7, c0, 0 @ invalidate caches 63 64 mcr p15, 0, r0, c6, c3 @ disable area 3~7 65 mcr p15, 0, r0, c6, c4 66 mcr p15, 0, r0, c6, c5 67 mcr p15, 0, r0, c6, c6 68 mcr p15, 0, r0, c6, c7 69 70 mov r0, #0x0000003F @ base = 0, size = 4GB 71 mcr p15, 0, r0, c6, c0 @ set area 0, default 72 73 ldr r0, =(CONFIG_DRAM_BASE & 0xFFFFF000) @ base[31:12] of RAM 74 ldr r3, =(CONFIG_DRAM_SIZE >> 12) @ size of RAM (must be >= 4KB) 75 mov r4, #10 @ 11 is the minimum (4KB) 76 1: add r4, r4, #1 @ area size *= 2 77 movs r3, r3, lsr #1 78 bne 1b @ count not zero r-shift 79 orr r0, r0, r4, lsl #1 @ the area register value 80 orr r0, r0, #1 @ set enable bit 81 mcr p15, 0, r0, c6, c1 @ set area 1, RAM 82 83 ldr r0, =(CONFIG_FLASH_MEM_BASE & 0xFFFFF000) @ base[31:12] of FLASH 84 ldr r3, =(CONFIG_FLASH_SIZE >> 12) @ size of FLASH (must be >= 4KB) 85 cmp r3, #0 86 moveq r0, #0 87 beq 2f 88 mov r4, #10 @ 11 is the minimum (4KB) 89 1: add r4, r4, #1 @ area size *= 2 90 movs r3, r3, lsr #1 91 bne 1b @ count not zero r-shift 92 orr r0, r0, r4, lsl #1 @ the area register value 93 orr r0, r0, #1 @ set enable bit 94 2: mcr p15, 0, r0, c6, c2 @ set area 2, ROM/FLASH 95 96 mov r0, #0x06 97 mcr p15, 0, r0, c2, c0 @ Region 1&2 cacheable 98 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH 99 mov r0, #0x00 @ disable whole write buffer 100 #else 101 mov r0, #0x02 @ Region 1 write bufferred 102 #endif 103 mcr p15, 0, r0, c3, c0 104 105 mov r0, #0x10000 106 sub r0, r0, #1 @ r0 = 0xffff 107 mcr p15, 0, r0, c5, c0 @ all read/write access 108 109 mrc p15, 0, r0, c1, c0 @ get control register 110 bic r0, r0, #0x3F000000 @ set to standard caching mode 111 @ need some benchmark 112 orr r0, r0, #0x0000000d @ MPU/Cache/WB 113 114 ret lr 115 116 .size __arm740_setup, . - __arm740_setup 117 118 __INITDATA 119 120 @ define struct processor (see <asm/proc-fns.h> and proc-macros.S) 121 define_processor_functions arm740, dabort=v4t_late_abort, pabort=legacy_pabort, nommu=1 122 123 .section ".rodata" 124 125 string cpu_arch_name, "armv4" 126 string cpu_elf_name, "v4" 127 string cpu_arm740_name, "ARM740T" 128 129 .align 130 131 .section ".proc.info.init", "a" 132 .type __arm740_proc_info,#object 133 __arm740_proc_info: 134 .long 0x41807400 135 .long 0xfffffff0 136 .long 0 137 .long 0 138 initfn __arm740_setup, __arm740_proc_info 139 .long cpu_arch_name 140 .long cpu_elf_name 141 .long HWCAP_SWP | HWCAP_HALF | HWCAP_THUMB | HWCAP_26BIT 142 .long cpu_arm740_name 143 .long arm740_processor_functions 144 .long 0 145 .long 0 146 .long v4_cache_fns @ cache model 147 .size __arm740_proc_info, . - __arm740_proc_info 148