LXR linux/arch/powerpc/mm/nohash/fsl

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Modifications by Kumar Gala (galak@kernel.crashing.org) to support
   4 * E500 Book E processors.
   5 *
   6 * Copyright 2004,2010 Freescale Semiconductor, Inc.
   7 *
   8 * This file contains the routines for initializing the MMU
   9 * on the 4xx series of chips.
  10 *  -- paulus
  11 *
  12 *  Derived from arch/ppc/mm/init.c:
  13 *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  14 *
  15 *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
  16 *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
  17 *    Copyright (C) 1996 Paul Mackerras
  18 *
  19 *  Derived from "arch/i386/mm/init.c"
  20 *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
  21 */
  22
  23#include <linux/signal.h>
  24#include <linux/sched.h>
  25#include <linux/kernel.h>
  26#include <linux/errno.h>
  27#include <linux/string.h>
  28#include <linux/types.h>
  29#include <linux/ptrace.h>
  30#include <linux/mman.h>
  31#include <linux/mm.h>
  32#include <linux/swap.h>
  33#include <linux/stddef.h>
  34#include <linux/vmalloc.h>
  35#include <linux/init.h>
  36#include <linux/delay.h>
  37#include <linux/highmem.h>
  38#include <linux/memblock.h>
  39
  40#include <asm/prom.h>
  41#include <asm/io.h>
  42#include <asm/mmu_context.h>
  43#include <asm/mmu.h>
  44#include <linux/uaccess.h>
  45#include <asm/smp.h>
  46#include <asm/machdep.h>
  47#include <asm/setup.h>
  48#include <asm/paca.h>
  49
  50#include <mm/mmu_decl.h>
  51
  52unsigned int tlbcam_index;
  53
  54#define NUM_TLBCAMS     (64)
  55struct tlbcam TLBCAM[NUM_TLBCAMS];
  56
  57struct tlbcamrange {
  58        unsigned long start;
  59        unsigned long limit;
  60        phys_addr_t phys;
  61} tlbcam_addrs[NUM_TLBCAMS];
  62
  63unsigned long tlbcam_sz(int idx)
  64{
  65        return tlbcam_addrs[idx].limit - tlbcam_addrs[idx].start + 1;
  66}
  67
  68#ifdef CONFIG_FSL_BOOKE
  69/*
  70 * Return PA for this VA if it is mapped by a CAM, or 0
  71 */
  72phys_addr_t v_block_mapped(unsigned long va)
  73{
  74        int b;
  75        for (b = 0; b < tlbcam_index; ++b)
  76                if (va >= tlbcam_addrs[b].start && va < tlbcam_addrs[b].limit)
  77                        return tlbcam_addrs[b].phys + (va - tlbcam_addrs[b].start);
  78        return 0;
  79}
  80
  81/*
  82 * Return VA for a given PA or 0 if not mapped
  83 */
  84unsigned long p_block_mapped(phys_addr_t pa)
  85{
  86        int b;
  87        for (b = 0; b < tlbcam_index; ++b)
  88                if (pa >= tlbcam_addrs[b].phys
  89                        && pa < (tlbcam_addrs[b].limit-tlbcam_addrs[b].start)
  90                              +tlbcam_addrs[b].phys)
  91                        return tlbcam_addrs[b].start+(pa-tlbcam_addrs[b].phys);
  92        return 0;
  93}
  94#endif
  95
  96/*
  97 * Set up a variable-size TLB entry (tlbcam). The parameters are not checked;
  98 * in particular size must be a power of 4 between 4k and the max supported by
  99 * an implementation; max may further be limited by what can be represented in
 100 * an unsigned long (for example, 32-bit implementations cannot support a 4GB
 101 * size).
 102 */
 103static void settlbcam(int index, unsigned long virt, phys_addr_t phys,
 104                unsigned long size, unsigned long flags, unsigned int pid)
 105{
 106        unsigned int tsize;
 107
 108        tsize = __ilog2(size) - 10;
 109
 110#if defined(CONFIG_SMP) || defined(CONFIG_PPC_E500MC)
 111        if ((flags & _PAGE_NO_CACHE) == 0)
 112                flags |= _PAGE_COHERENT;
 113#endif
 114
 115        TLBCAM[index].MAS0 = MAS0_TLBSEL(1) | MAS0_ESEL(index) | MAS0_NV(index+1);
 116        TLBCAM[index].MAS1 = MAS1_VALID | MAS1_IPROT | MAS1_TSIZE(tsize) | MAS1_TID(pid);
 117        TLBCAM[index].MAS2 = virt & PAGE_MASK;
 118
 119        TLBCAM[index].MAS2 |= (flags & _PAGE_WRITETHRU) ? MAS2_W : 0;
 120        TLBCAM[index].MAS2 |= (flags & _PAGE_NO_CACHE) ? MAS2_I : 0;
 121        TLBCAM[index].MAS2 |= (flags & _PAGE_COHERENT) ? MAS2_M : 0;
 122        TLBCAM[index].MAS2 |= (flags & _PAGE_GUARDED) ? MAS2_G : 0;
 123        TLBCAM[index].MAS2 |= (flags & _PAGE_ENDIAN) ? MAS2_E : 0;
 124
 125        TLBCAM[index].MAS3 = (phys & MAS3_RPN) | MAS3_SX | MAS3_SR;
 126        TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_SW : 0);
 127        if (mmu_has_feature(MMU_FTR_BIG_PHYS))
 128                TLBCAM[index].MAS7 = (u64)phys >> 32;
 129
 130        /* Below is unlikely -- only for large user pages or similar */
 131        if (pte_user(__pte(flags))) {
 132           TLBCAM[index].MAS3 |= MAS3_UX | MAS3_UR;
 133           TLBCAM[index].MAS3 |= ((flags & _PAGE_RW) ? MAS3_UW : 0);
 134        }
 135
 136        tlbcam_addrs[index].start = virt;
 137        tlbcam_addrs[index].limit = virt + size - 1;
 138        tlbcam_addrs[index].phys = phys;
 139}
 140
 141unsigned long calc_cam_sz(unsigned long ram, unsigned long virt,
 142                          phys_addr_t phys)
 143{
 144        unsigned int camsize = __ilog2(ram);
 145        unsigned int align = __ffs(virt | phys);
 146        unsigned long max_cam;
 147
 148        if ((mfspr(SPRN_MMUCFG) & MMUCFG_MAVN) == MMUCFG_MAVN_V1) {
 149                /* Convert (4^max) kB to (2^max) bytes */
 150                max_cam = ((mfspr(SPRN_TLB1CFG) >> 16) & 0xf) * 2 + 10;
 151                camsize &= ~1U;
 152                align &= ~1U;
 153        } else {
 154                /* Convert (2^max) kB to (2^max) bytes */
 155                max_cam = __ilog2(mfspr(SPRN_TLB1PS)) + 10;
 156        }
 157
 158        if (camsize > align)
 159                camsize = align;
 160        if (camsize > max_cam)
 161                camsize = max_cam;
 162
 163        return 1UL << camsize;
 164}
 165
 166static unsigned long map_mem_in_cams_addr(phys_addr_t phys, unsigned long virt,
 167                                        unsigned long ram, int max_cam_idx,
 168                                        bool dryrun)
 169{
 170        int i;
 171        unsigned long amount_mapped = 0;
 172
 173        /* Calculate CAM values */
 174        for (i = 0; ram && i < max_cam_idx; i++) {
 175                unsigned long cam_sz;
 176
 177                cam_sz = calc_cam_sz(ram, virt, phys);
 178                if (!dryrun)
 179                        settlbcam(i, virt, phys, cam_sz,
 180                                  pgprot_val(PAGE_KERNEL_X), 0);
 181
 182                ram -= cam_sz;
 183                amount_mapped += cam_sz;
 184                virt += cam_sz;
 185                phys += cam_sz;
 186        }
 187
 188        if (dryrun)
 189                return amount_mapped;
 190
 191        loadcam_multi(0, i, max_cam_idx);
 192        tlbcam_index = i;
 193
 194#ifdef CONFIG_PPC64
 195        get_paca()->tcd.esel_next = i;
 196        get_paca()->tcd.esel_max = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
 197        get_paca()->tcd.esel_first = i;
 198#endif
 199
 200        return amount_mapped;
 201}
 202
 203unsigned long map_mem_in_cams(unsigned long ram, int max_cam_idx, bool dryrun)
 204{
 205        unsigned long virt = PAGE_OFFSET;
 206        phys_addr_t phys = memstart_addr;
 207
 208        return map_mem_in_cams_addr(phys, virt, ram, max_cam_idx, dryrun);
 209}
 210
 211#ifdef CONFIG_PPC32
 212
 213#if defined(CONFIG_LOWMEM_CAM_NUM_BOOL) && (CONFIG_LOWMEM_CAM_NUM >= NUM_TLBCAMS)
 214#error "LOWMEM_CAM_NUM must be less than NUM_TLBCAMS"
 215#endif
 216
 217unsigned long __init mmu_mapin_ram(unsigned long base, unsigned long top)
 218{
 219        return tlbcam_addrs[tlbcam_index - 1].limit - PAGE_OFFSET + 1;
 220}
 221
 222void flush_instruction_cache(void)
 223{
 224        unsigned long tmp;
 225
 226        tmp = mfspr(SPRN_L1CSR1);
 227        tmp |= L1CSR1_ICFI | L1CSR1_ICLFR;
 228        mtspr(SPRN_L1CSR1, tmp);
 229        isync();
 230}
 231
 232/*
 233 * MMU_init_hw does the chip-specific initialization of the MMU hardware.
 234 */
 235void __init MMU_init_hw(void)
 236{
 237        flush_instruction_cache();
 238}
 239
 240void __init adjust_total_lowmem(void)
 241{
 242        unsigned long ram;
 243        int i;
 244
 245        /* adjust lowmem size to __max_low_memory */
 246        ram = min((phys_addr_t)__max_low_memory, (phys_addr_t)total_lowmem);
 247
 248        i = switch_to_as1();
 249        __max_low_memory = map_mem_in_cams(ram, CONFIG_LOWMEM_CAM_NUM, false);
 250        restore_to_as0(i, 0, 0, 1);
 251
 252        pr_info("Memory CAM mapping: ");
 253        for (i = 0; i < tlbcam_index - 1; i++)
 254                pr_cont("%lu/", tlbcam_sz(i) >> 20);
 255        pr_cont("%lu Mb, residual: %dMb\n", tlbcam_sz(tlbcam_index - 1) >> 20,
 256                (unsigned int)((total_lowmem - __max_low_memory) >> 20));
 257
 258        memblock_set_current_limit(memstart_addr + __max_low_memory);
 259}
 260
 261void setup_initial_memory_limit(phys_addr_t first_memblock_base,
 262                                phys_addr_t first_memblock_size)
 263{
 264        phys_addr_t limit = first_memblock_base + first_memblock_size;
 265
 266        /* 64M mapped initially according to head_fsl_booke.S */
 267        memblock_set_current_limit(min_t(u64, limit, 0x04000000));
 268}
 269
 270#ifdef CONFIG_RELOCATABLE
 271int __initdata is_second_reloc;
 272notrace void __init relocate_init(u64 dt_ptr, phys_addr_t start)
 273{
 274        unsigned long base = kernstart_virt_addr;
 275        phys_addr_t size;
 276
 277        kernstart_addr = start;
 278        if (is_second_reloc) {
 279                virt_phys_offset = PAGE_OFFSET - memstart_addr;
 280                kaslr_late_init();
 281                return;
 282        }
 283
 284        /*
 285         * Relocatable kernel support based on processing of dynamic
 286         * relocation entries. Before we get the real memstart_addr,
 287         * We will compute the virt_phys_offset like this:
 288         * virt_phys_offset = stext.run - kernstart_addr
 289         *
 290         * stext.run = (KERNELBASE & ~0x3ffffff) +
 291         *                              (kernstart_addr & 0x3ffffff)
 292         * When we relocate, we have :
 293         *
 294         *      (kernstart_addr & 0x3ffffff) = (stext.run & 0x3ffffff)
 295         *
 296         * hence:
 297         *  virt_phys_offset = (KERNELBASE & ~0x3ffffff) -
 298         *                              (kernstart_addr & ~0x3ffffff)
 299         *
 300         */
 301        start &= ~0x3ffffff;
 302        base &= ~0x3ffffff;
 303        virt_phys_offset = base - start;
 304        early_get_first_memblock_info(__va(dt_ptr), &size);
 305        /*
 306         * We now get the memstart_addr, then we should check if this
 307         * address is the same as what the PAGE_OFFSET map to now. If
 308         * not we have to change the map of PAGE_OFFSET to memstart_addr
 309         * and do a second relocation.
 310         */
 311        if (start != memstart_addr) {
 312                int n;
 313                long offset = start - memstart_addr;
 314
 315                is_second_reloc = 1;
 316                n = switch_to_as1();
 317                /* map a 64M area for the second relocation */
 318                if (memstart_addr > start)
 319                        map_mem_in_cams(0x4000000, CONFIG_LOWMEM_CAM_NUM,
 320                                        false);
 321                else
 322                        map_mem_in_cams_addr(start, PAGE_OFFSET + offset,
 323                                        0x4000000, CONFIG_LOWMEM_CAM_NUM,
 324                                        false);
 325                restore_to_as0(n, offset, __va(dt_ptr), 1);
 326                /* We should never reach here */
 327                panic("Relocation error");
 328        }
 329
 330        kaslr_early_init(__va(dt_ptr), size);
 331}
 332#endif
 333#endif
 334