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