fsl_booke_mmu.c revision 0aef996b37d08757562ecf0bb0c1f6998e634c8b
1/* 2 * Modifications by Kumar Gala (galak@kernel.crashing.org) to support 3 * E500 Book E processors. 4 * 5 * Copyright 2004 Freescale Semiconductor, Inc 6 * 7 * This file contains the routines for initializing the MMU 8 * on the 4xx series of chips. 9 * -- paulus 10 * 11 * Derived from arch/ppc/mm/init.c: 12 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 13 * 14 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 15 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 16 * Copyright (C) 1996 Paul Mackerras 17 * 18 * Derived from "arch/i386/mm/init.c" 19 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 20 * 21 * This program is free software; you can redistribute it and/or 22 * modify it under the terms of the GNU General Public License 23 * as published by the Free Software Foundation; either version 24 * 2 of the License, or (at your option) any later version. 25 * 26 */ 27 28#include <linux/signal.h> 29#include <linux/sched.h> 30#include <linux/kernel.h> 31#include <linux/errno.h> 32#include <linux/string.h> 33#include <linux/types.h> 34#include <linux/ptrace.h> 35#include <linux/mman.h> 36#include <linux/mm.h> 37#include <linux/swap.h> 38#include <linux/stddef.h> 39#include <linux/vmalloc.h> 40#include <linux/init.h> 41#include <linux/delay.h> 42#include <linux/highmem.h> 43 44#include <asm/pgalloc.h> 45#include <asm/prom.h> 46#include <asm/io.h> 47#include <asm/mmu_context.h> 48#include <asm/pgtable.h> 49#include <asm/mmu.h> 50#include <asm/uaccess.h> 51#include <asm/smp.h> 52#include <asm/machdep.h> 53#include <asm/setup.h> 54 55#include "mmu_decl.h" 56 57extern void loadcam_entry(unsigned int index); 58unsigned int tlbcam_index; 59unsigned int num_tlbcam_entries; 60static unsigned long __cam0, __cam1, __cam2; 61 62#define NUM_TLBCAMS (16) 63 64struct tlbcam { 65 u32 MAS0; 66 u32 MAS1; 67 u32 MAS2; 68 u32 MAS3; 69 u32 MAS7; 70} TLBCAM[NUM_TLBCAMS]; 71 72struct tlbcamrange { 73 unsigned long start; 74 unsigned long limit; 75 phys_addr_t phys; 76} tlbcam_addrs[NUM_TLBCAMS]; 77 78extern unsigned int tlbcam_index; 79 80/* 81 * Return PA for this VA if it is mapped by a CAM, or 0 82 */ 83unsigned long v_mapped_by_tlbcam(unsigned long va) 84{ 85 int b; 86 for (b = 0; b < tlbcam_index; ++b) 87 if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit) 88 return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start); 89 return 0; 90} 91 92/* 93 * Return VA for a given PA or 0 if not mapped 94 */ 95unsigned long p_mapped_by_tlbcam(unsigned long pa) 96{ 97 int b; 98 for (b = 0; b < tlbcam_index; ++b) 99 if (pa >= tlbcam_addrs[b].phys 100 && pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start) 101 +tlbcam_addrs[b].phys) 102 return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys); 103 return 0; 104} 105 106/* 107 * Set up one of the I/D BAT (block address translation) register pairs. 108 * The parameters are not checked; in particular size must be a power 109 * of 4 between 4k and 256M. 110 */ 111void settlbcam(int index, unsigned long virt, phys_addr_t phys, 112 unsigned int size, int flags, unsigned int pid) 113{ 114 unsigned int tsize, lz; 115 116 asm ("cntlzw %0,%1" : "=r" (lz) : "r" (size)); 117 tsize = (21 - lz) / 2; 118 119#ifdef CONFIG_SMP 120 if ((flags & _PAGE_NO_CACHE) == 0) 121 flags |= _PAGE_COHERENT; 122#endif 123 124 TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1); 125 TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid); 126 TLBCAM[index].MAS2 = virt & PAGE_MASK; 127 128 TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0; 129 TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0; 130 TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0; 131 TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0; 132 TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0; 133 134 TLBCAM[index].MAS3 = (phys & PAGE_MASK) | MAS3_SX | MAS3_SR; 135 TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0); 136 137#ifndef CONFIG_KGDB /* want user access for breakpoints */ 138 if (flags & _PAGE_USER) { 139 TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR; 140 TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0); 141 } 142#else 143 TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR; 144 TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0); 145#endif 146 147 tlbcam_addrs[index].start = virt; 148 tlbcam_addrs[index].limit = virt + size - 1; 149 tlbcam_addrs[index].phys = phys; 150 151 loadcam_entry(index); 152} 153 154void invalidate_tlbcam_entry(int index) 155{ 156 TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index); 157 TLBCAM[index].MAS1 = ~MAS1_VALID; 158 159 loadcam_entry(index); 160} 161 162void __init cam_mapin_ram(unsigned long cam0, unsigned long cam1, 163 unsigned long cam2) 164{ 165 settlbcam(0, PAGE_OFFSET, memstart_addr, cam0, _PAGE_KERNEL, 0); 166 tlbcam_index++; 167 if (cam1) { 168 tlbcam_index++; 169 settlbcam(1, PAGE_OFFSET+cam0, memstart_addr+cam0, cam1, _PAGE_KERNEL, 0); 170 } 171 if (cam2) { 172 tlbcam_index++; 173 settlbcam(2, PAGE_OFFSET+cam0+cam1, memstart_addr+cam0+cam1, cam2, _PAGE_KERNEL, 0); 174 } 175} 176 177/* 178 * MMU_init_hw does the chip-specific initialization of the MMU hardware. 179 */ 180void __init MMU_init_hw(void) 181{ 182 flush_instruction_cache(); 183} 184 185unsigned long __init mmu_mapin_ram(void) 186{ 187 cam_mapin_ram(__cam0, __cam1, __cam2); 188 189 return __cam0 + __cam1 + __cam2; 190} 191 192 193void __init 194adjust_total_lowmem(void) 195{ 196 phys_addr_t max_lowmem_size = __max_low_memory; 197 phys_addr_t cam_max_size = 0x10000000; 198 phys_addr_t ram; 199 200 /* adjust CAM size to max_lowmem_size */ 201 if (max_lowmem_size < cam_max_size) 202 cam_max_size = max_lowmem_size; 203 204 /* adjust lowmem size to max_lowmem_size */ 205 ram = min(max_lowmem_size, total_lowmem); 206 207 /* Calculate CAM values */ 208 __cam0 = 1UL << 2 * (__ilog2(ram) / 2); 209 if (__cam0 > cam_max_size) 210 __cam0 = cam_max_size; 211 ram -= __cam0; 212 if (ram) { 213 __cam1 = 1UL << 2 * (__ilog2(ram) / 2); 214 if (__cam1 > cam_max_size) 215 __cam1 = cam_max_size; 216 ram -= __cam1; 217 } 218 if (ram) { 219 __cam2 = 1UL << 2 * (__ilog2(ram) / 2); 220 if (__cam2 > cam_max_size) 221 __cam2 = cam_max_size; 222 ram -= __cam2; 223 } 224 225 printk(KERN_INFO "Memory CAM mapping: CAM0=%ldMb, CAM1=%ldMb," 226 " CAM2=%ldMb residual: %ldMb\n", 227 __cam0 >> 20, __cam1 >> 20, __cam2 >> 20, 228 (total_lowmem - __cam0 - __cam1 - __cam2) >> 20); 229 __max_low_memory = __cam0 + __cam1 + __cam2; 230 __initial_memory_limit = memstart_addr + __max_low_memory; 231} 232