arch/powerpc/mm/nohash/fsl_booke.c

   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
  52 unsigned int tlbcam_index;
  53
  54 #define NUM_TLBCAMS     (64)
  55 struct tlbcam TLBCAM[NUM_TLBCAMS];
  56
  57 struct tlbcamrange {
  58         unsigned long start;
  59         unsigned long limit;
  60         phys_addr_t phys;
  61 } tlbcam_addrs[NUM_TLBCAMS];
  62
  63 unsigned 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  */
  72 phys_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  */
  84 unsigned 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  */
 103 static 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
 141 unsigned 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
 166 static 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
 203 unsigned 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
 217 unsigned 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
 222 void 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  */
 235 void __init MMU_init_hw(void)
 236 {
 237         flush_instruction_cache();
 238 }
 239
 240 void __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
 261 void 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
 271 int __initdata is_second_reloc;
 272 notrace 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