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use RBIT instruction of Thumb-2

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This commit is contained in:
NIIBE Yutaka
2012-06-05 10:33:50 +09:00
parent 1164ac4d28
commit bfa4952f31
4 changed files with 31 additions and 72 deletions
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8
src/usb_ctrl.c
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@@ -188,11 +188,11 @@ static const uint8_t *const mem_info[] = { &_regnual_start, &__heap_end__, };
#define USB_FSIJ_GNUK_DOWNLOAD 1
#define USB_FSIJ_GNUK_EXEC 2
static uint32_t reverse32 (uint32_t v)
static uint32_t rbit (uint32_t v)
{
uint32_t r;
r = (v << 24) | ((v & 0xff00) << 8) | ((v & 0xff0000) >> 8) | (v >> 24);
asm ("rbit %0, %1" : "=r" (r) : "r" (v));
return r;
}
@@ -206,9 +206,9 @@ static int download_check_crc32 (const uint32_t *end_p)
CRC->CR = CRC_CR_RESET;
for (p = (const uint32_t *)&_regnual_start; p < end_p; p++)
CRC->DR = reverse32 (*p);
CRC->DR = rbit (*p);
if ((CRC->DR ^ crc32) == 0xffffffff)
if ((rbit (CRC->DR) ^ crc32) == 0xffffffff)
return USB_SUCCESS;
return USB_UNSUPPORT;