Cortex-M7——Cache

Cortex-M7——Cache

小狼@http://blog.youkuaiyun.com/xiaolangyangyang

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1、M7 Cache基本参数

ARM Cortex-M系列从M7内核才开始有的Cache，M7 Cache参数如下：

• Cache Level：L1
• ICache Size：32K，2-way set-associative
• DCache Size：32K，4-way set associative
• Cache Line：32B

这样节省地址标签，不用每个行都标记一个地址。

2、M7 Cache处理函数（core_cm7.h）

SCB_EnableICache()
SCB_DisableICache()
SCB_InvalidateICache()
SCB_EnableDCache()
SCB_DisableDCache()
SCB_InvalidateDCache()
SCB_CleanDCache()
SCB_CleanInvalidateDCache()
SCB_InvalidateDCache_by_Addr()
SCB_CleanDCache_by_Addr()
SCB_CleanInvalidateDCache_by_Addr()

3、M7 Cahce处理函数原型

SCB_EnableICache

__STATIC_INLINE void SCB_EnableICache (void)
{
  #if defined (__ICACHE_PRESENT) && (__ICACHE_PRESENT == 1U)
    __DSB();
    __ISB();
    SCB->ICIALLU = 0UL;                     /* invalidate I-Cache */
    __DSB();
    __ISB();
    SCB->CCR |=  (uint32_t)SCB_CCR_IC_Msk;  /* enable I-Cache */
    __DSB();
    __ISB();
  #endif
}

SCB_DisableICache

__STATIC_INLINE void SCB_DisableICache (void)
{
  #if defined (__ICACHE_PRESENT) && (__ICACHE_PRESENT == 1U)
    __DSB();
    __ISB();
    SCB->CCR &= ~(uint32_t)SCB_CCR_IC_Msk;  /* disable I-Cache */
    SCB->ICIALLU = 0UL;                     /* invalidate I-Cache */
    __DSB();
    __ISB();
  #endif
}

SCB_InvalidateICache

__STATIC_INLINE void SCB_InvalidateICache (void)
{
  #if defined (__ICACHE_PRESENT) && (__ICACHE_PRESENT == 1U)
    __DSB();
    __ISB();
    SCB->ICIALLU = 0UL;
    __DSB();
    __ISB();
  #endif
}

SCB_EnableDCache

__STATIC_INLINE void SCB_EnableDCache (void)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
    uint32_t ccsidr;
    uint32_t sets;
    uint32_t ways;

    SCB->CSSELR = 0U; /*(0U << 1U) | 0U;*/  /* Level 1 data cache */
    __DSB();

    ccsidr = SCB->CCSIDR;

                                            /* invalidate D-Cache */
    sets = (uint32_t)(CCSIDR_SETS(ccsidr));
    do {
      ways = (uint32_t)(CCSIDR_WAYS(ccsidr));
      do {
        SCB->DCISW = (((sets << SCB_DCISW_SET_Pos) & SCB_DCISW_SET_Msk) |
                      ((ways << SCB_DCISW_WAY_Pos) & SCB_DCISW_WAY_Msk)  );
        #if defined ( __CC_ARM )
          __schedule_barrier();
        #endif
      } while (ways-- != 0U);
    } while(sets-- != 0U);
    __DSB();

    SCB->CCR |=  (uint32_t)SCB_CCR_DC_Msk;  /* enable D-Cache */

    __DSB();
    __ISB();
  #endif
}

SCB_DisableDCache

__STATIC_INLINE void SCB_DisableDCache (void)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
    register uint32_t ccsidr;
    register uint32_t sets;
    register uint32_t ways;

    SCB->CSSELR = 0U; /*(0U << 1U) | 0U;*/  /* Level 1 data cache */
    __DSB();

    SCB->CCR &= ~(uint32_t)SCB_CCR_DC_Msk;  /* disable D-Cache */
    __DSB();

    ccsidr = SCB->CCSIDR;

                                            /* clean & invalidate D-Cache */
    sets = (uint32_t)(CCSIDR_SETS(ccsidr));
    do {
      ways = (uint32_t)(CCSIDR_WAYS(ccsidr));
      do {
        SCB->DCCISW = (((sets << SCB_DCCISW_SET_Pos) & SCB_DCCISW_SET_Msk) |
                       ((ways << SCB_DCCISW_WAY_Pos) & SCB_DCCISW_WAY_Msk)  );
        #if defined ( __CC_ARM )
          __schedule_barrier();
        #endif
      } while (ways-- != 0U);
    } while(sets-- != 0U);

    __DSB();
    __ISB();
  #endif
}

SCB_InvalidateDCache

__STATIC_INLINE void SCB_CleanDCache (void)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
    uint32_t ccsidr;
    uint32_t sets;
    uint32_t ways;

     SCB->CSSELR = 0U; /*(0U << 1U) | 0U;*/  /* Level 1 data cache */
   __DSB();

    ccsidr = SCB->CCSIDR;

                                            /* clean D-Cache */
    sets = (uint32_t)(CCSIDR_SETS(ccsidr));
    do {
      ways = (uint32_t)(CCSIDR_WAYS(ccsidr));
      do {
        SCB->DCCSW = (((sets << SCB_DCCSW_SET_Pos) & SCB_DCCSW_SET_Msk) |
                      ((ways << SCB_DCCSW_WAY_Pos) & SCB_DCCSW_WAY_Msk)  );
        #if defined ( __CC_ARM )
          __schedule_barrier();
        #endif
      } while (ways-- != 0U);
    } while(sets-- != 0U);

    __DSB();
    __ISB();
  #endif
}

SCB_CleanDCache

__STATIC_INLINE void SCB_CleanDCache (void)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
    uint32_t ccsidr;
    uint32_t sets;
    uint32_t ways;

     SCB->CSSELR = 0U; /*(0U << 1U) | 0U;*/  /* Level 1 data cache */
   __DSB();

    ccsidr = SCB->CCSIDR;

                                            /* clean D-Cache */
    sets = (uint32_t)(CCSIDR_SETS(ccsidr));
    do {
      ways = (uint32_t)(CCSIDR_WAYS(ccsidr));
      do {
        SCB->DCCSW = (((sets << SCB_DCCSW_SET_Pos) & SCB_DCCSW_SET_Msk) |
                      ((ways << SCB_DCCSW_WAY_Pos) & SCB_DCCSW_WAY_Msk)  );
        #if defined ( __CC_ARM )
          __schedule_barrier();
        #endif
      } while (ways-- != 0U);
    } while(sets-- != 0U);

    __DSB();
    __ISB();
  #endif
}

SCB_CleanInvalidateDCache

__STATIC_INLINE void SCB_CleanInvalidateDCache (void)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
    uint32_t ccsidr;
    uint32_t sets;
    uint32_t ways;

    SCB->CSSELR = 0U; /*(0U << 1U) | 0U;*/  /* Level 1 data cache */
    __DSB();

    ccsidr = SCB->CCSIDR;

                                            /* clean & invalidate D-Cache */
    sets = (uint32_t)(CCSIDR_SETS(ccsidr));
    do {
      ways = (uint32_t)(CCSIDR_WAYS(ccsidr));
      do {
        SCB->DCCISW = (((sets << SCB_DCCISW_SET_Pos) & SCB_DCCISW_SET_Msk) |
                       ((ways << SCB_DCCISW_WAY_Pos) & SCB_DCCISW_WAY_Msk)  );
        #if defined ( __CC_ARM )
          __schedule_barrier();
        #endif
      } while (ways-- != 0U);
    } while(sets-- != 0U);

    __DSB();
    __ISB();
  #endif
}

SCB_InvalidateDCache_by_Addr

__STATIC_INLINE void SCB_InvalidateDCache_by_Addr (uint32_t *addr, int32_t dsize)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
     int32_t op_size = dsize;
    uint32_t op_addr = (uint32_t)addr;
     int32_t linesize = 32;           /* in Cortex-M7 size of cache line is fixed to 8 words (32 bytes) */

    __DSB();

    while (op_size > 0) {
      SCB->DCIMVAC = op_addr;
      op_addr += (uint32_t)linesize;
      op_size -=           linesize;
    }

    __DSB();
    __ISB();
  #endif
}

SCB_CleanDCache_by_Addr

__STATIC_INLINE void SCB_CleanDCache_by_Addr (uint32_t *addr, int32_t dsize)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
     int32_t op_size = dsize;
    uint32_t op_addr = (uint32_t) addr;
     int32_t linesize = 32;            /* in Cortex-M7 size of cache line is fixed to 8 words (32 bytes) */

    __DSB();

    while (op_size > 0) {
      SCB->DCCMVAC = op_addr;
      op_addr += (uint32_t)linesize;
      op_size -=           linesize;
    }

    __DSB();
    __ISB();
  #endif
}

SCB_CleanInvalidateDCache_by_Addr

__STATIC_INLINE void SCB_CleanInvalidateDCache_by_Addr (uint32_t *addr, int32_t dsize)
{
  #if defined (__DCACHE_PRESENT) && (__DCACHE_PRESENT == 1U)
     int32_t op_size = dsize;
    uint32_t op_addr = (uint32_t) addr;
     int32_t linesize = 32;          /* in Cortex-M7 size of cache line is fixed to 8 words (32 bytes) */

    __DSB();

    while (op_size > 0) {
      SCB->DCCIMVAC = op_addr;
      op_addr += (uint32_t)linesize;
      op_size -=           linesize;
    }

    __DSB();
    __ISB();
  #endif
}

• 参数addr：Cache Line对齐（32Byte）；
• 参数dsize：Cache Line整数倍（32Byte*N）。