关于OALPAtoCA()疑问

531496955

关于OALPAtoCA()疑问 [复制链接]

在eboot加载NK的时候用到了这个函数：

#define IMAGE_WINCE_CODE_PA 0x80001000
#define IMAGE_WINCE_CODE_SIZE 0x04000000
pData = OALPAtoCA(IMAGE_WINCE_CODE_PA);

复制代码

在MSDN上描述OALPAtoCA：This function returns the cached virtual address for a specified physical address.
但是IMAGE_WINCE_CODE_PA地址应该不是物理地址吧？？？

eaglet_121

我的BSP里边没这个定义，你看下OALPAtoCA函数的处理也许能判断出来是怎样的吧

mamh

必须得
给你拉段代码

#if defined(MIPS) || defined(SHx)

#define OALPAtoCA(pa)    (VOID*)(((UINT32)(pa))|0x80000000)
#define OALPAtoUA(pa)    (VOID*)(((UINT32)(pa))|0xA0000000)
#define OALPAtoVA(pa, c) (VOID*)((c)?(pa)|0x80000000:(pa)|0xA0000000)
#define OALVAtoPA(va)    (((UINT32)(va))&~0xE0000000)

#else

#define OALPAtoCA(pa)    OALPAtoVA(pa, TRUE)
#define OALPAtoUA(pa)    OALPAtoVA(pa, FALSE)

VOID* OALPAtoVA(UINT32 pa, BOOL cached);
UINT32 OALVAtoPA(VOID *va);

#endif

VOID* OALPAtoVA(UINT32 pa, BOOL cached)
{
OAL_ADDRESS_TABLE *pTable = g_oalAddressTable;
VOID *va = NULL;

OALMSG(OAL_MEMORY&&OAL_FUNC, (L"+OALPAtoVA(0x%x, %d)\r\n", pa, cached));

// Search the table for address range
while (pTable->size != 0) {
      if (
         pa >= pTable->PA &&
         pa <= (pTable->PA + (pTable->size << 20) - 1)
      ) break;                   // match found
      pTable++;
}

// If address table entry is valid compute the VA
if (pTable->size != 0) {
      va = (VOID *)(pTable->CA + (pa - pTable->PA));
      // If VA is uncached, set the uncached bit
      if (!cached) (UINT32)va |= OAL_MEMORY_CACHE_BIT;
}

// Indicate the virtual address
OALMSG(OAL_MEMORY&&OAL_FUNC, (L"-OALPAtoVA(va = 0x%08x)\r\n", va));
return va;
}