hal_cache.h

移植到WLIT项目的redboot源代码

    asm volatile (                                                      \
        "mrc  p15,0,r1,c1,c0,0;"                                        \
        "orr  r1,r1,#0x000F;" /* enable DCache (also ensures    */      \
                              /* the MMU, alignment faults, and */      \
                              /* write buffer are enabled)      */      \
        "mcr  p15,0,r1,c1,c0,0"                                         \
        :                                                               \
        :                                                               \
        : "r1" /* Clobber list */                                       \
        );                                                              \
CYG_MACRO_END

// Disable the data cache (and invalidate it, required semanitcs)
#define HAL_DCACHE_DISABLE()                                            \
CYG_MACRO_START                                                         \
    asm volatile (                                                      \
        "mrc  p15,0,r1,c1,c0,0;"                                        \
        "bic  r1,r1,#0x000C;" /* disable DCache AND write buffer  */    \
                              /* but not MMU and alignment faults */    \
        "mcr  p15,0,r1,c1,c0,0;"                                        \
        "mcr  p15,0,r1,c7,c6,0" /* clear data cache */                  \
        :                                                               \
        :                                                               \
        : "r1" /* Clobber list */                                       \
        );                                                              \
CYG_MACRO_END

// Query the state of the data cache
#define HAL_DCACHE_IS_ENABLED(_state_)                                   \
CYG_MACRO_START                                                          \
    register int reg;                                                    \
    asm volatile ("mrc  p15,0,%0,c1,c0,0;"                               \
                  : "=r"(reg)                                            \
                  :                                                      \
        );                                                               \
    (_state_) = (0 != (4 & reg)); /* Bit 2 is DCache enable */           \
CYG_MACRO_END

// Flush the entire dcache (and then both TLBs, just in case)
#define HAL_DCACHE_INVALIDATE_ALL()                                     \
CYG_MACRO_START                                                         \
    /* this macro can discard dirty cache lines. */                     \
    asm volatile ("mcr    p15,0,r1,c7,c6,0;"                            \
                  "mcr    p15,0,r1,c8,c7,0;"                            \
                  : : );                                                \
CYG_MACRO_END


// Synchronize the contents of the cache with memory.
#define HAL_DCACHE_SYNC()                                               \
CYG_MACRO_START                                                         \
    /* This is slightly naff in that the only way to force a dirty */   \
    /* line out is by loading other data into its slot, so         */   \
    /* invalidating that slot.                                     */   \
    asm volatile (                                                      \
        "mov    r0, #0xE0000000;" /* SA11X0 zeros bank (128Mb) */       \
        "add    r1, r0, #0x2000;" /* We read 8kB of it */               \
 "667: "                                                                \
        "ldr    r2, [r0], #32;"                                         \
        "teq    r1, r0;"                                                \
        "bne    667b;"                                                  \
        "mcr    p15,0,r0,c7,c6,0;"  /* flush DCache */                  \
        "mcr    p15,0,r0,c7,c10,4;" /* and drain the write buffer */    \
        "nop;"  /* wait for the writebacks to occur...     */           \
        "nop;"                                                          \
        "nop;"                                                          \
        "nop;"                                                          \
        "nop;"                                                          \
        "nop;"                                                          \
        :                                                               \
        :                                                               \
        : "r0","r1","r2" /* Clobber list */                             \
        );                                                              \
CYG_MACRO_END

// Set the data cache refill burst size
//#define HAL_DCACHE_BURST_SIZE(_size_)
// This feature is not available on the SA11X0.

// Set the data cache write mode
//#define HAL_DCACHE_WRITE_MODE( _mode_ )
// This feature is not available on the SA11X0.

#define HAL_DCACHE_WRITETHRU_MODE       0
#define HAL_DCACHE_WRITEBACK_MODE       1

// Get the current writeback mode - or only writeback mode if fixed
#define HAL_DCACHE_QUERY_WRITE_MODE( _mode_ ) CYG_MACRO_START           \
    _mode_ = HAL_DCACHE_WRITEBACK_MODE;                                 \
CYG_MACRO_END

// Load the contents of the given address range into the data cache
// and then lock the cache so that it stays there.
//#define HAL_DCACHE_LOCK(_base_, _size_)
// This feature is not available on the SA11X0.

// Undo a previous lock operation
//#define HAL_DCACHE_UNLOCK(_base_, _size_)
// This feature is not available on the SA11X0.

// Unlock entire cache
//#define HAL_DCACHE_UNLOCK_ALL()
// This feature is not available on the SA11X0.

//-----------------------------------------------------------------------------
// Data cache line control

// Allocate cache lines for the given address range without reading its
// contents from memory.
//#define HAL_DCACHE_ALLOCATE( _base_ , _size_ )
// This feature is not available on the SA11X0.

// Write dirty cache lines to memory and invalidate the cache entries
// for the given address range.
// ---- this seems not to work despite the documentation ---
//#define HAL_DCACHE_FLUSH( _base_ , _size_ )
//CYG_MACRO_START
//    HAL_DCACHE_STORE( _base_ , _size_ );
//    HAL_DCACHE_INVALIDATE( _base_ , _size_ );
//CYG_MACRO_END

// Invalidate cache lines in the given range without writing to memory.
// ---- this seems not to work despite the documentation ---
//#define HAL_DCACHE_INVALIDATE( _base_ , _size_ )
//CYG_MACRO_START
//    register int addr, enda;
//    for ( addr = (~(HAL_DCACHE_LINE_SIZE - 1)) & (int)(_base_),
//              enda = (int)(_base_) + (_size_);
//          addr < enda ;
//          addr += HAL_DCACHE_LINE_SIZE )
//    {
//        asm volatile (
//                      "mcr  p15,0,%0,c7,c6,1;" /* flush entry away */
//                      :
//                      : "r"(addr)
//                      : "memory"
//            );
//    }
//CYG_MACRO_END
                          
// Write dirty cache lines to memory for the given address range.
// ---- this seems not to work despite the documentation ---
//#define HAL_DCACHE_STORE( _base_ , _size_ )
//CYG_MACRO_START
//    register int addr, enda;
//    for ( addr = (~(HAL_DCACHE_LINE_SIZE - 1)) & (int)(_base_),
//              enda = (int)(_base_) + (_size_);
//          addr < enda ;
//          addr += HAL_DCACHE_LINE_SIZE )
//    {
//        asm volatile ("mcr  p15,0,%0,c7,c10,1;" /* push entry to RAM */
//                      :
//                      : "r"(addr)
//                      : "memory"
//            );
//    }
//CYG_MACRO_END

// Preread the given range into the cache with the intention of reading
// from it later.
//#define HAL_DCACHE_READ_HINT( _base_ , _size_ )
// This feature is available on the SA11X0, but due to tricky
// coherency issues with the read buffer (see SA11X0 developer's
// manual page 6-7) we don't bother to implement it here.

// Preread the given range into the cache with the intention of writing
// to it later.
//#define HAL_DCACHE_WRITE_HINT( _base_ , _size_ )
// This feature is not available on the SA11X0.

// Allocate and zero the cache lines associated with the given range.
//#define HAL_DCACHE_ZERO( _base_ , _size_ )
// This feature is not available on the SA11X0.

//-----------------------------------------------------------------------------
#endif // ifndef CYGONCE_HAL_CACHE_H
// End of hal_cache.h