static A_STATUS AllocateDMABounceBuffer(HIF_DEVICE *device, HIF_SCATTER_DMA_BOUNCE_INFO *pBounceInfo)
{
A_STATUS status = A_OK;
A_UINT32 temp;
SDDMA_DESCRIPTION *pDescription;
pDescription = SDGET_DMA_DESCRIPTION(device->handle);
do {
pBounceInfo->BufferSize = MAX_SCATTER_REQ_TRANSFER_SIZE + 2*(A_GET_CACHE_LINE_BYTES());
/* allocate the bounce buffer */
pBounceInfo->pBounceBuffer = (A_UINT8 *)kmalloc(pBounceInfo->BufferSize,
GFP_KERNEL | GFP_DMA | GFP_ATOMIC);
if (NULL == pBounceInfo->pBounceBuffer) {
AR_DEBUG_PRINTF(ATH_DEBUG_ERROR,("HIF : *** unable to allocate bounce buffer \n"));
status = A_NO_MEMORY;
break;
}
temp = (A_UINT32)A_ALIGN_TO_CACHE_LINE(pBounceInfo->pBounceBuffer);
/* check bounce buffer address alignment */
if ((temp & pDescription->AddressAlignment) == 0) {
/* no illegal address bits */
break;
}
/* free the buffer we just allocated, we need to allocate a larger buffer */
FreeBounceBuffer(device, pBounceInfo);
/* increase buffer size by padding it by the required alignment */
pBounceInfo->BufferSize = MAX_SCATTER_REQ_TRANSFER_SIZE + 2*(A_GET_CACHE_LINE_BYTES()) +
(pDescription->AddressAlignment + 1);
pBounceInfo->pBounceBuffer = (A_UINT8 *)kmalloc(pBounceInfo->BufferSize,
GFP_KERNEL | GFP_DMA | GFP_ATOMIC);
if (NULL == pBounceInfo->pBounceBuffer) {
AR_DEBUG_PRINTF(ATH_DEBUG_ERROR,("HIF : *** unable to allocate bounce buffer \n"));
status = A_NO_MEMORY;
break;
}
/* figure out required alignment */
temp = (A_UINT32)A_ALIGN_TO_CACHE_LINE(pBounceInfo->pBounceBuffer);
temp += (pDescription->AddressAlignment + 1);
temp &= ~pDescription->AddressAlignment;
pBounceInfo->AlignmentOffset = temp - (A_UINT32)pBounceInfo->pBounceBuffer;
AR_DEBUG_PRINTF(ATH_DEBUG_WARN,("HIF : Bounce Buffer (0x%X) will apply alignment: %d \n",
(A_UINT32)pBounceInfo->pBounceBuffer, pBounceInfo->AlignmentOffset));
} while (FALSE);
return status;
}
/* function to set up virtual scatter support if HIF layer has not implemented the interface */
static A_STATUS DevSetupVirtualScatterSupport(AR6K_DEVICE *pDev)
{
A_STATUS status = A_OK;
int bufferSize, sgreqSize;
int i;
DEV_SCATTER_DMA_VIRTUAL_INFO *pVirtualInfo;
HIF_SCATTER_REQ *pReq;
bufferSize = sizeof(DEV_SCATTER_DMA_VIRTUAL_INFO) +
2 * (A_GET_CACHE_LINE_BYTES()) + AR6K_MAX_TRANSFER_SIZE_PER_SCATTER;
sgreqSize = sizeof(HIF_SCATTER_REQ) +
(AR6K_SCATTER_ENTRIES_PER_REQ - 1) * (sizeof(HIF_SCATTER_ITEM));
for (i = 0; i < AR6K_SCATTER_REQS; i++) {
/* allocate the scatter request, buffer info and the actual virtual buffer itself */
pReq = (HIF_SCATTER_REQ *)A_MALLOC(sgreqSize + bufferSize);
if (NULL == pReq) {
status = A_NO_MEMORY;
break;
}
A_MEMZERO(pReq, sgreqSize);
/* the virtual DMA starts after the scatter request struct */
pVirtualInfo = (DEV_SCATTER_DMA_VIRTUAL_INFO *)((A_UINT8 *)pReq + sgreqSize);
A_MEMZERO(pVirtualInfo, sizeof(DEV_SCATTER_DMA_VIRTUAL_INFO));
pVirtualInfo->pVirtDmaBuffer = &pVirtualInfo->DataArea[0];
/* align buffer to cache line in case host controller can actually DMA this */
pVirtualInfo->pVirtDmaBuffer = A_ALIGN_TO_CACHE_LINE(pVirtualInfo->pVirtDmaBuffer);
/* store the structure in the private area */
pReq->HIFPrivate[0] = pVirtualInfo;
/* we emulate a DMA bounce interface */
pReq->ScatterMethod = HIF_SCATTER_DMA_BOUNCE;
pReq->pScatterBounceBuffer = pVirtualInfo->pVirtDmaBuffer;
/* free request to the list */
DevFreeScatterReq((HIF_DEVICE *)pDev,pReq);
}
if (A_FAILED(status)) {
DevCleanupVirtualScatterSupport(pDev);
} else {
pDev->HifScatterInfo.pAllocateReqFunc = DevAllocScatterReq;
pDev->HifScatterInfo.pFreeReqFunc = DevFreeScatterReq;
pDev->HifScatterInfo.pReadWriteScatterFunc = DevReadWriteScatter;
if (pDev->MailBoxInfo.MboxBusIFType == MBOX_BUS_IF_SPI) {
AR_DEBUG_PRINTF(ATH_DEBUG_WARN, ("AR6K: SPI bus requires RX scatter limits\n"));
pDev->HifScatterInfo.MaxScatterEntries = AR6K_MIN_SCATTER_ENTRIES_PER_REQ;
pDev->HifScatterInfo.MaxTransferSizePerScatterReq = AR6K_MIN_TRANSFER_SIZE_PER_SCATTER;
} else {
pDev->HifScatterInfo.MaxScatterEntries = AR6K_SCATTER_ENTRIES_PER_REQ;
pDev->HifScatterInfo.MaxTransferSizePerScatterReq = AR6K_MAX_TRANSFER_SIZE_PER_SCATTER;
}
pDev->ScatterIsVirtual = TRUE;
}
return status;
}
