int dma_free_channel(DMA_Handle_t handle /* */
) {
int rc = 0;
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
if (down_interruptible(&gDMA.lock) < 0) {
return -ERESTARTSYS;
}
channel = HandleToChannel(handle);
if (channel == NULL) {
rc = -EINVAL;
goto out;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) == 0) {
channel->lastDevType = channel->devType;
channel->devType = DMA_DEVICE_NONE;
}
channel->flags &= ~DMA_CHANNEL_FLAG_IN_USE;
devAttr->flags &= ~DMA_DEVICE_FLAG_IN_USE;
out:
up(&gDMA.lock);
wake_up_interruptible(&gDMA.freeChannelQ);
return rc;
}
static int ConfigChannel(DMA_Handle_t handle)
{
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int controllerIdx;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
controllerIdx = CONTROLLER_FROM_HANDLE(handle);
if ((devAttr->flags & DMA_DEVICE_FLAG_PORT_PER_DMAC) != 0) {
if (devAttr->config.transferType ==
dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL) {
devAttr->config.dstPeripheralPort =
devAttr->dmacPort[controllerIdx];
} else if (devAttr->config.transferType ==
dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM) {
devAttr->config.srcPeripheralPort =
devAttr->dmacPort[controllerIdx];
}
}
if (dmacHw_configChannel(channel->dmacHwHandle, &devAttr->config) != 0) {
printk(KERN_ERR "ConfigChannel: dmacHw_configChannel failed\n");
return -EIO;
}
return 0;
}
int dma_stop_transfer(DMA_Handle_t handle)
{
DMA_Channel_t *channel;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
dmacHw_stopTransfer(channel->dmacHwHandle);
return 0;
}
int dma_transfer(DMA_Handle_t handle, /* */
dmacHw_TRANSFER_TYPE_e transferType, /* */
dma_addr_t srcData, /* */
dma_addr_t dstData, /* */
size_t numBytes /* */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
if (devAttr->config.transferType != transferType) {
return -EINVAL;
}
/* */
/* */
/* */
{
rc =
dma_alloc_descriptors(handle, transferType, srcData,
dstData, numBytes);
if (rc != 0) {
return rc;
}
}
/* */
devAttr->numBytes = numBytes;
devAttr->transferStartTime = timer_get_tick_count();
dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
devAttr->ring.virtAddr);
/* */
return 0;
}
int dma_transfer(DMA_Handle_t handle, /* DMA Handle */
dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
dma_addr_t srcData, /* Place to get data to write to device */
dma_addr_t dstData, /* Pointer to device data address */
size_t numBytes /* Number of bytes to transfer to the device */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
if (devAttr->config.transferType != transferType) {
return -EINVAL;
}
/* We keep track of the information about the previous request for this */
/* device, and if the attributes match, then we can use the descriptors we setup */
/* the last time, and not have to reinitialize everything. */
{
rc =
dma_alloc_descriptors(handle, transferType, srcData,
dstData, numBytes);
if (rc != 0) {
return rc;
}
}
/* And kick off the transfer */
devAttr->numBytes = numBytes;
devAttr->transferStartTime = timer_get_tick_count();
dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
devAttr->ring.virtAddr);
/* Since we got this far, everything went successfully */
return 0;
}
int dma_start_transfer(DMA_Handle_t handle)
{
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
devAttr->ring.virtAddr);
/* */
return 0;
}
int dma_wait_transfer_done(DMA_Handle_t handle)
{
DMA_Channel_t *channel;
dmacHw_TRANSFER_STATUS_e status;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
while ((status =
dmacHw_transferCompleted(channel->dmacHwHandle)) ==
dmacHw_TRANSFER_STATUS_BUSY) {
;
}
if (status == dmacHw_TRANSFER_STATUS_ERROR) {
printk(KERN_ERR "%s: DMA transfer failed\n", __func__);
return -EIO;
}
return 0;
}
int dma_init(void)
{
int rc = 0;
int controllerIdx;
int channelIdx;
DMA_Device_t devIdx;
DMA_Channel_t *channel;
DMA_Handle_t dedicatedHandle;
memset(&gDMA, 0, sizeof(gDMA));
sema_init(&gDMA.lock, 0);
init_waitqueue_head(&gDMA.freeChannelQ);
/* */
dmacHw_initDma();
/* */
for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
controllerIdx++) {
for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
channelIdx++) {
channel =
&gDMA.controller[controllerIdx].channel[channelIdx];
channel->flags = 0;
channel->devType = DMA_DEVICE_NONE;
channel->lastDevType = DMA_DEVICE_NONE;
#if (DMA_DEBUG_TRACK_RESERVATION)
channel->fileName = "";
channel->lineNum = 0;
#endif
channel->dmacHwHandle =
dmacHw_getChannelHandle(dmacHw_MAKE_CHANNEL_ID
(controllerIdx,
channelIdx));
dmacHw_initChannel(channel->dmacHwHandle);
}
}
/* */
gDMA.controller[0].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
gDMA.controller[0].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
gDMA.controller[1].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
gDMA.controller[1].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
/* */
for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
if (((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0)
&& ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0)) {
printk(KERN_ERR
"DMA Device: %s Can only request NO_ISR for dedicated devices\n",
devAttr->name);
rc = -EINVAL;
goto out;
}
if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
/* */
if (devAttr->dedicatedController >= DMA_NUM_CONTROLLERS) {
printk(KERN_ERR
"DMA Device: %s DMA Controller %d is out of range\n",
devAttr->name,
devAttr->dedicatedController);
rc = -EINVAL;
goto out;
}
if (devAttr->dedicatedChannel >= DMA_NUM_CHANNELS) {
printk(KERN_ERR
"DMA Device: %s DMA Channel %d is out of range\n",
devAttr->name,
devAttr->dedicatedChannel);
rc = -EINVAL;
goto out;
}
dedicatedHandle =
MAKE_HANDLE(devAttr->dedicatedController,
devAttr->dedicatedChannel);
channel = HandleToChannel(dedicatedHandle);
if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
0) {
printk
("DMA Device: %s attempting to use same DMA Controller:Channel (%d:%d) as %s\n",
devAttr->name,
devAttr->dedicatedController,
devAttr->dedicatedChannel,
DMA_gDeviceAttribute[channel->devType].
name);
rc = -EBUSY;
goto out;
}
channel->flags |= DMA_CHANNEL_FLAG_IS_DEDICATED;
channel->devType = devIdx;
if (devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) {
channel->flags |= DMA_CHANNEL_FLAG_NO_ISR;
}
/* */
/* */
ConfigChannel(dedicatedHandle);
}
}
/* */
for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
controllerIdx++) {
for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
channelIdx++) {
channel =
&gDMA.controller[controllerIdx].channel[channelIdx];
if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) == 0) {
snprintf(channel->name, sizeof(channel->name),
"dma %d:%d %s", controllerIdx,
channelIdx,
channel->devType ==
DMA_DEVICE_NONE ? "" :
DMA_gDeviceAttribute[channel->devType].
name);
rc =
request_irq(IRQ_DMA0C0 +
(controllerIdx *
DMA_NUM_CHANNELS) +
channelIdx,
dma_interrupt_handler,
IRQF_DISABLED, channel->name,
channel);
if (rc != 0) {
printk(KERN_ERR
"request_irq for IRQ_DMA%dC%d failed\n",
controllerIdx, channelIdx);
}
}
}
}
/* */
gDmaDir = proc_mkdir("dma", NULL);
if (gDmaDir == NULL) {
printk(KERN_ERR "Unable to create /proc/dma\n");
} else {
create_proc_read_entry("channels", 0, gDmaDir,
dma_proc_read_channels, NULL);
create_proc_read_entry("devices", 0, gDmaDir,
dma_proc_read_devices, NULL);
}
out:
up(&gDMA.lock);
return rc;
}
int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* */
dma_addr_t srcData, /* */
dma_addr_t dstData1, /* */
dma_addr_t dstData2, /* */
size_t numBytes /* */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int numDst1Descriptors;
int numDst2Descriptors;
int numDescriptors;
size_t ringBytesRequired;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
/* */
/* */
/* */
numDst1Descriptors =
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
(void *)dstData1, numBytes);
if (numDst1Descriptors < 0) {
return -EINVAL;
}
numDst2Descriptors =
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
(void *)dstData2, numBytes);
if (numDst2Descriptors < 0) {
return -EINVAL;
}
numDescriptors = numDst1Descriptors + numDst2Descriptors;
/* */
/* */
/* */
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
/* */
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
/* */
/* */
/* */
might_sleep();
/* */
dma_free_descriptor_ring(&devAttr->ring);
/* */
rc =
dma_alloc_descriptor_ring(&devAttr->ring,
numDescriptors);
if (rc < 0) {
printk(KERN_ERR
"%s: dma_alloc_descriptor_ring(%d) failed\n",
__func__, ringBytesRequired);
return rc;
}
}
/* */
/* */
/* */
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
devAttr->ring.physAddr,
devAttr->ring.bytesAllocated,
numDescriptors) < 0) {
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n", __func__);
return -EINVAL;
}
/* */
/* */
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData1, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 1 failed\n",
__func__);
return -EINVAL;
}
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData2, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 2 failed\n",
__func__);
return -EINVAL;
}
/* */
/* */
devAttr->prevSrcData = 0;
devAttr->prevDstData = 0;
devAttr->prevNumBytes = 0;
return numDescriptors;
}
int dma_alloc_descriptors(DMA_Handle_t handle, /* */
dmacHw_TRANSFER_TYPE_e transferType, /* */
dma_addr_t srcData, /* */
dma_addr_t dstData, /* */
size_t numBytes /* */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int numDescriptors;
size_t ringBytesRequired;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
if (devAttr->config.transferType != transferType) {
return -EINVAL;
}
/* */
/* */
/* */
numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
(void *)srcData,
(void *)dstData,
numBytes);
if (numDescriptors < 0) {
printk(KERN_ERR "%s: dmacHw_calculateDescriptorCount failed\n",
__func__);
return -EINVAL;
}
/* */
/* */
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
/* */
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
/* */
/* */
/* */
might_sleep();
/* */
dma_free_descriptor_ring(&devAttr->ring);
/* */
rc =
dma_alloc_descriptor_ring(&devAttr->ring,
numDescriptors);
if (rc < 0) {
printk(KERN_ERR
"%s: dma_alloc_descriptor_ring(%d) failed\n",
__func__, numDescriptors);
return rc;
}
/* */
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
devAttr->ring.physAddr,
devAttr->ring.bytesAllocated,
numDescriptors) < 0) {
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n",
__func__);
return -EINVAL;
}
} else {
/* */
/* */
dmacHw_resetDescriptorControl(devAttr->ring.virtAddr);
}
/* */
/* */
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor failed\n",
__func__);
return -EINVAL;
}
/* */
/* */
devAttr->prevSrcData = srcData;
devAttr->prevDstData = dstData;
devAttr->prevNumBytes = numBytes;
return 0;
}
int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* DMA Handle */
dma_addr_t srcData, /* Physical address of source data */
dma_addr_t dstData1, /* Physical address of first destination buffer */
dma_addr_t dstData2, /* Physical address of second destination buffer */
size_t numBytes /* Number of bytes in each destination buffer */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int numDst1Descriptors;
int numDst2Descriptors;
int numDescriptors;
size_t ringBytesRequired;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
/* Figure out how many descriptors we need. */
/* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
/* srcData, dstData, numBytes); */
numDst1Descriptors =
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
(void *)dstData1, numBytes);
if (numDst1Descriptors < 0) {
return -EINVAL;
}
numDst2Descriptors =
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
(void *)dstData2, numBytes);
if (numDst2Descriptors < 0) {
return -EINVAL;
}
numDescriptors = numDst1Descriptors + numDst2Descriptors;
/* printk("numDescriptors: %d\n", numDescriptors); */
/* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
/* a new one. */
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
/* printk("ringBytesRequired: %d\n", ringBytesRequired); */
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
/* Make sure that this code path is never taken from interrupt context. */
/* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
/* allocation needs to have already been done. */
might_sleep();
/* Free the old descriptor ring and allocate a new one. */
dma_free_descriptor_ring(&devAttr->ring);
/* And allocate a new one. */
rc =
dma_alloc_descriptor_ring(&devAttr->ring,
numDescriptors);
if (rc < 0) {
printk(KERN_ERR
"%s: dma_alloc_descriptor_ring(%d) failed\n",
__func__, ringBytesRequired);
return rc;
}
}
/* Setup the descriptor for this transfer. Since this function is used with */
/* CONTINUOUS DMA operations, we need to reinitialize every time, otherwise */
/* setDataDescriptor will keep trying to append onto the end. */
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
devAttr->ring.physAddr,
devAttr->ring.bytesAllocated,
numDescriptors) < 0) {
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n", __func__);
return -EINVAL;
}
/* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
/* as last time, then we don't need to call setDataDescriptor again. */
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData1, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 1 failed\n",
__func__);
return -EINVAL;
}
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData2, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 2 failed\n",
__func__);
return -EINVAL;
}
/* You should use dma_start_transfer rather than dma_transfer_xxx so we don't */
/* try to make the 'prev' variables right. */
devAttr->prevSrcData = 0;
devAttr->prevDstData = 0;
devAttr->prevNumBytes = 0;
return numDescriptors;
}
int dma_alloc_descriptors(DMA_Handle_t handle, /* DMA Handle */
dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
dma_addr_t srcData, /* Place to get data to write to device */
dma_addr_t dstData, /* Pointer to device data address */
size_t numBytes /* Number of bytes to transfer to the device */
) {
DMA_Channel_t *channel;
DMA_DeviceAttribute_t *devAttr;
int numDescriptors;
size_t ringBytesRequired;
int rc = 0;
channel = HandleToChannel(handle);
if (channel == NULL) {
return -ENODEV;
}
devAttr = &DMA_gDeviceAttribute[channel->devType];
if (devAttr->config.transferType != transferType) {
return -EINVAL;
}
/* Figure out how many descriptors we need. */
/* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
/* srcData, dstData, numBytes); */
numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
(void *)srcData,
(void *)dstData,
numBytes);
if (numDescriptors < 0) {
printk(KERN_ERR "%s: dmacHw_calculateDescriptorCount failed\n",
__func__);
return -EINVAL;
}
/* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
/* a new one. */
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
/* printk("ringBytesRequired: %d\n", ringBytesRequired); */
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
/* Make sure that this code path is never taken from interrupt context. */
/* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
/* allocation needs to have already been done. */
might_sleep();
/* Free the old descriptor ring and allocate a new one. */
dma_free_descriptor_ring(&devAttr->ring);
/* And allocate a new one. */
rc =
dma_alloc_descriptor_ring(&devAttr->ring,
numDescriptors);
if (rc < 0) {
printk(KERN_ERR
"%s: dma_alloc_descriptor_ring(%d) failed\n",
__func__, numDescriptors);
return rc;
}
/* Setup the descriptor for this transfer */
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
devAttr->ring.physAddr,
devAttr->ring.bytesAllocated,
numDescriptors) < 0) {
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n",
__func__);
return -EINVAL;
}
} else {
/* We've already got enough ring buffer allocated. All we need to do is reset */
/* any control information, just in case the previous DMA was stopped. */
dmacHw_resetDescriptorControl(devAttr->ring.virtAddr);
}
/* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
/* as last time, then we don't need to call setDataDescriptor again. */
if (dmacHw_setDataDescriptor(&devAttr->config,
devAttr->ring.virtAddr,
(void *)srcData,
(void *)dstData, numBytes) < 0) {
printk(KERN_ERR "%s: dmacHw_setDataDescriptor failed\n",
__func__);
return -EINVAL;
}
/* Remember the critical information for this transfer so that we can eliminate */
/* another call to dma_alloc_descriptors if the caller reuses the same buffers */
devAttr->prevSrcData = srcData;
devAttr->prevDstData = dstData;
devAttr->prevNumBytes = numBytes;
return 0;
}