uboot/arch/arm/lib/cache-cp15.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * (C) Copyright 2002
   4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   5 */
   6
   7#include <common.h>
   8#include <cpu_func.h>
   9#include <log.h>
  10#include <asm/global_data.h>
  11#include <asm/system.h>
  12#include <asm/cache.h>
  13#include <linux/compiler.h>
  14#include <asm/armv7_mpu.h>
  15
  16#if !(CONFIG_IS_ENABLED(SYS_ICACHE_OFF) && CONFIG_IS_ENABLED(SYS_DCACHE_OFF))
  17
  18DECLARE_GLOBAL_DATA_PTR;
  19
  20#ifdef CONFIG_SYS_ARM_MMU
  21__weak void arm_init_before_mmu(void)
  22{
  23}
  24
  25__weak void arm_init_domains(void)
  26{
  27}
  28
  29static void set_section_phys(int section, phys_addr_t phys,
  30                             enum dcache_option option)
  31{
  32#ifdef CONFIG_ARMV7_LPAE
  33        u64 *page_table = (u64 *)gd->arch.tlb_addr;
  34        /* Need to set the access flag to not fault */
  35        u64 value = TTB_SECT_AP | TTB_SECT_AF;
  36#else
  37        u32 *page_table = (u32 *)gd->arch.tlb_addr;
  38        u32 value = TTB_SECT_AP;
  39#endif
  40
  41        /* Add the page offset */
  42        value |= phys;
  43
  44        /* Add caching bits */
  45        value |= option;
  46
  47        /* Set PTE */
  48        page_table[section] = value;
  49}
  50
  51void set_section_dcache(int section, enum dcache_option option)
  52{
  53        set_section_phys(section, (u32)section << MMU_SECTION_SHIFT, option);
  54}
  55
  56__weak void mmu_page_table_flush(unsigned long start, unsigned long stop)
  57{
  58        debug("%s: Warning: not implemented\n", __func__);
  59}
  60
  61void mmu_set_region_dcache_behaviour_phys(phys_addr_t start, phys_addr_t phys,
  62                                        size_t size, enum dcache_option option)
  63{
  64#ifdef CONFIG_ARMV7_LPAE
  65        u64 *page_table = (u64 *)gd->arch.tlb_addr;
  66#else
  67        u32 *page_table = (u32 *)gd->arch.tlb_addr;
  68#endif
  69        unsigned long startpt, stoppt;
  70        unsigned long upto, end;
  71
  72        /* div by 2 before start + size to avoid phys_addr_t overflow */
  73        end = ALIGN((start / 2) + (size / 2), MMU_SECTION_SIZE / 2)
  74              >> (MMU_SECTION_SHIFT - 1);
  75        start = start >> MMU_SECTION_SHIFT;
  76
  77#ifdef CONFIG_ARMV7_LPAE
  78        debug("%s: start=%pa, size=%zu, option=%llx\n", __func__, &start, size,
  79              option);
  80#else
  81        debug("%s: start=%pa, size=%zu, option=0x%x\n", __func__, &start, size,
  82              option);
  83#endif
  84        for (upto = start; upto < end; upto++, phys += MMU_SECTION_SIZE)
  85                set_section_phys(upto, phys, option);
  86
  87        /*
  88         * Make sure range is cache line aligned
  89         * Only CPU maintains page tables, hence it is safe to always
  90         * flush complete cache lines...
  91         */
  92
  93        startpt = (unsigned long)&page_table[start];
  94        startpt &= ~(CONFIG_SYS_CACHELINE_SIZE - 1);
  95        stoppt = (unsigned long)&page_table[end];
  96        stoppt = ALIGN(stoppt, CONFIG_SYS_CACHELINE_SIZE);
  97        mmu_page_table_flush(startpt, stoppt);
  98}
  99
 100void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
 101                                     enum dcache_option option)
 102{
 103        mmu_set_region_dcache_behaviour_phys(start, start, size, option);
 104}
 105
 106__weak void dram_bank_mmu_setup(int bank)
 107{
 108        struct bd_info *bd = gd->bd;
 109        int     i;
 110
 111        /* bd->bi_dram is available only after relocation */
 112        if ((gd->flags & GD_FLG_RELOC) == 0)
 113                return;
 114
 115        debug("%s: bank: %d\n", __func__, bank);
 116        for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
 117             i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
 118                 (bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
 119             i++)
 120                set_section_dcache(i, DCACHE_DEFAULT_OPTION);
 121}
 122
 123/* to activate the MMU we need to set up virtual memory: use 1M areas */
 124static inline void mmu_setup(void)
 125{
 126        int i;
 127        u32 reg;
 128
 129        arm_init_before_mmu();
 130        /* Set up an identity-mapping for all 4GB, rw for everyone */
 131        for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
 132                set_section_dcache(i, DCACHE_OFF);
 133
 134        for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
 135                dram_bank_mmu_setup(i);
 136        }
 137
 138#if defined(CONFIG_ARMV7_LPAE) && __LINUX_ARM_ARCH__ != 4
 139        /* Set up 4 PTE entries pointing to our 4 1GB page tables */
 140        for (i = 0; i < 4; i++) {
 141                u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
 142                u64 tpt = gd->arch.tlb_addr + (4096 * i);
 143                page_table[i] = tpt | TTB_PAGETABLE;
 144        }
 145
 146        reg = TTBCR_EAE;
 147#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
 148        reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
 149#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
 150        reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
 151#else
 152        reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
 153#endif
 154
 155        if (is_hyp()) {
 156                /* Set HTCR to enable LPAE */
 157                asm volatile("mcr p15, 4, %0, c2, c0, 2"
 158                        : : "r" (reg) : "memory");
 159                /* Set HTTBR0 */
 160                asm volatile("mcrr p15, 4, %0, %1, c2"
 161                        :
 162                        : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
 163                        : "memory");
 164                /* Set HMAIR */
 165                asm volatile("mcr p15, 4, %0, c10, c2, 0"
 166                        : : "r" (MEMORY_ATTRIBUTES) : "memory");
 167        } else {
 168                /* Set TTBCR to enable LPAE */
 169                asm volatile("mcr p15, 0, %0, c2, c0, 2"
 170                        : : "r" (reg) : "memory");
 171                /* Set 64-bit TTBR0 */
 172                asm volatile("mcrr p15, 0, %0, %1, c2"
 173                        :
 174                        : "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
 175                        : "memory");
 176                /* Set MAIR */
 177                asm volatile("mcr p15, 0, %0, c10, c2, 0"
 178                        : : "r" (MEMORY_ATTRIBUTES) : "memory");
 179        }
 180#elif defined(CONFIG_CPU_V7A)
 181        if (is_hyp()) {
 182                /* Set HTCR to disable LPAE */
 183                asm volatile("mcr p15, 4, %0, c2, c0, 2"
 184                        : : "r" (0) : "memory");
 185        } else {
 186                /* Set TTBCR to disable LPAE */
 187                asm volatile("mcr p15, 0, %0, c2, c0, 2"
 188                        : : "r" (0) : "memory");
 189        }
 190        /* Set TTBR0 */
 191        reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
 192#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
 193        reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT;
 194#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
 195        reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA;
 196#else
 197        reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB;
 198#endif
 199        asm volatile("mcr p15, 0, %0, c2, c0, 0"
 200                     : : "r" (reg) : "memory");
 201#else
 202        /* Copy the page table address to cp15 */
 203        asm volatile("mcr p15, 0, %0, c2, c0, 0"
 204                     : : "r" (gd->arch.tlb_addr) : "memory");
 205#endif
 206        /* Set the access control to all-supervisor */
 207        asm volatile("mcr p15, 0, %0, c3, c0, 0"
 208                     : : "r" (~0));
 209
 210        arm_init_domains();
 211
 212        /* and enable the mmu */
 213        reg = get_cr(); /* get control reg. */
 214        set_cr(reg | CR_M);
 215}
 216
 217static int mmu_enabled(void)
 218{
 219        return get_cr() & CR_M;
 220}
 221#endif /* CONFIG_SYS_ARM_MMU */
 222
 223/* cache_bit must be either CR_I or CR_C */
 224static void cache_enable(uint32_t cache_bit)
 225{
 226        uint32_t reg;
 227
 228        /* The data cache is not active unless the mmu/mpu is enabled too */
 229#ifdef CONFIG_SYS_ARM_MMU
 230        if ((cache_bit == CR_C) && !mmu_enabled())
 231                mmu_setup();
 232#elif defined(CONFIG_SYS_ARM_MPU)
 233        if ((cache_bit == CR_C) && !mpu_enabled()) {
 234                printf("Consider enabling MPU before enabling caches\n");
 235                return;
 236        }
 237#endif
 238        reg = get_cr(); /* get control reg. */
 239        set_cr(reg | cache_bit);
 240}
 241
 242/* cache_bit must be either CR_I or CR_C */
 243static void cache_disable(uint32_t cache_bit)
 244{
 245        uint32_t reg;
 246
 247        reg = get_cr();
 248
 249        if (cache_bit == CR_C) {
 250                /* if cache isn;t enabled no need to disable */
 251                if ((reg & CR_C) != CR_C)
 252                        return;
 253#ifdef CONFIG_SYS_ARM_MMU
 254                /* if disabling data cache, disable mmu too */
 255                cache_bit |= CR_M;
 256#endif
 257        }
 258        reg = get_cr();
 259
 260#ifdef CONFIG_SYS_ARM_MMU
 261        if (cache_bit == (CR_C | CR_M))
 262#elif defined(CONFIG_SYS_ARM_MPU)
 263        if (cache_bit == CR_C)
 264#endif
 265                flush_dcache_all();
 266        set_cr(reg & ~cache_bit);
 267}
 268#endif
 269
 270#if CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
 271void icache_enable(void)
 272{
 273        return;
 274}
 275
 276void icache_disable(void)
 277{
 278        return;
 279}
 280
 281int icache_status(void)
 282{
 283        return 0;                                       /* always off */
 284}
 285#else
 286void icache_enable(void)
 287{
 288        cache_enable(CR_I);
 289}
 290
 291void icache_disable(void)
 292{
 293        cache_disable(CR_I);
 294}
 295
 296int icache_status(void)
 297{
 298        return (get_cr() & CR_I) != 0;
 299}
 300#endif
 301
 302#if CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
 303void dcache_enable(void)
 304{
 305        return;
 306}
 307
 308void dcache_disable(void)
 309{
 310        return;
 311}
 312
 313int dcache_status(void)
 314{
 315        return 0;                                       /* always off */
 316}
 317#else
 318void dcache_enable(void)
 319{
 320        cache_enable(CR_C);
 321}
 322
 323void dcache_disable(void)
 324{
 325        cache_disable(CR_C);
 326}
 327
 328int dcache_status(void)
 329{
 330        return (get_cr() & CR_C) != 0;
 331}
 332#endif
 333