/**
*
* Read a CompactFlash sector. This is a blocking, low-level function which
* does not return until the specified sector is read.
*
* @param BaseAddress is the base address of the device
* @param SectorId is the id of the sector to read
* @param BufferPtr is a pointer to a buffer where the data will be stored.
*
* @return
*
* The number of bytes read. If this number is not equal to the sector size,
* 512 bytes, then an error occurred.
*
* @note
*
* None.
*
******************************************************************************/
int XSysAce_ReadSector(Xuint32 BaseAddress, Xuint32 SectorId, Xuint8 *BufferPtr)
{
int NumRead;
/* Request and wait for the lock */
XSysAce_mWaitForLock(BaseAddress);
/* See if the CF is ready for a command */
if (!XSysAce_mIsReadyForCmd(BaseAddress))
{
return 0;
}
/* Write the sector ID (LBA) */
XSysAce_RegWrite32(BaseAddress + XSA_MLR_OFFSET, SectorId);
/* Send a read command of one sector to the controller */
XSysAce_RegWrite16(BaseAddress + XSA_SCCR_OFFSET,
XSA_SCCR_READDATA_MASK | 1);
/* Reset configuration controller (be sure to keep the lock) */
XSysAce_mOrControlReg(BaseAddress, XSA_CR_CFGRESET_MASK);
/* Read a sector of data from the data buffer */
NumRead = XSysAce_ReadDataBuffer(BaseAddress, BufferPtr,
XSA_CF_SECTOR_SIZE);
/* Clear reset of configuration controller and locks */
XSysAce_mAndControlReg(BaseAddress, ~(XSA_CR_CFGRESET_MASK |
XSA_CR_LOCKREQ_MASK));
return NumRead;
}
/**
*
* Handle a data-buffer-ready interrupt. If we get the interrupt when reading,
* it means there is still data to read since the interrupt does not occur after
* reading the last data buffer. If we get the interrupt when writing, there
* may or may not be data left to write since the interrupt does occur after the
* last data buffer is written.
*
* @param InstancePtr is a pointer to the XSysAce instance to be worked on.
* @param StatusReg is the contents of the status register, read at the start
* of the interrupt service routine.
*
* @return
*
* None.
*
* @note
*
* None.
*
******************************************************************************/
static void HandleDataBuffer(XSysAce * InstancePtr, u32 StatusReg)
{
/* By default, transfer a whole data buffer */
int BytesToTransfer = XSA_DATA_BUFFER_SIZE;
/*
* Check to see if number of bytes remaining is less than the data buffer
* size. If it is, we need to adjust the remaining bytes to transfer.
*/
if (InstancePtr->NumRemaining < XSA_DATA_BUFFER_SIZE) {
BytesToTransfer = InstancePtr->NumRemaining;
}
/*
* Transfer only one data buffer at a time, which is 32 bytes. Note that
* errors will be handled by an error interrupt occurring, so no need to
* check for them here.
*/
if (StatusReg & XSA_SR_DATABUFMODE_MASK) {
/*
* A write operation in progress, so if there is data remaining then
* write the buffer. If no data is remaining, clean up.
*/
if (InstancePtr->NumRemaining > 0) {
(void) XSysAce_WriteDataBuffer(InstancePtr->BaseAddress,
InstancePtr->BufferPtr,
BytesToTransfer);
/*
* Decrement the number of bytes remaining to be transferred and
* adjust the buffer pointer appropriately.
*/
InstancePtr->NumRemaining -= BytesToTransfer;
InstancePtr->BufferPtr += BytesToTransfer;
}
else {
/* Done writing data, so clean up */
DataComplete(InstancePtr);
}
}
else {
/* A read operation in progress, so read the buffer */
(void) XSysAce_ReadDataBuffer(InstancePtr->BaseAddress,
InstancePtr->BufferPtr,
BytesToTransfer);
/*
* Decrement the number of bytes remaining to be transferred and
* adjust the buffer pointer appropriately. If it was the last buffer,
* we're done and we can cleanup.
*/
InstancePtr->NumRemaining -= BytesToTransfer;
InstancePtr->BufferPtr += BytesToTransfer;
if (InstancePtr->NumRemaining == 0) {
/* Done reading data, so clean up */
DataComplete(InstancePtr);
}
}
}
/**
*
* Read at least one sector of data from the CompactFlash. The user specifies
* the starting sector ID and the number of sectors to be read. The minimum unit
* that can be read from the CompactFlash is a sector, which is 512 bytes.
*
* In polled mode, this read is blocking. If there are other tasks in the system
* that must run, it is best to keep the number of sectors to be read to a
* minimum (e.g., 1). In interrupt mode, this read is non-blocking and an event,
* XSA_EVENT_DATA_DONE, is returned to the user in the asynchronous event
* handler when the read is complete. The user must call
* XSysAce_EnableInterrupt() to put the driver/device into interrupt mode.
*
* An MPU lock, obtained using XSysAce_Lock(), must be granted before calling
* this function. If a lock has not been granted, no action is taken and an
* error is returned.
*
* @param InstancePtr is a pointer to the XSysAce instance.
* @param StartSector is the starting sector ID from where data will
* be read.
* Sector IDs range from 0 (first sector) to 0x10000000.
* @param NumSectors is the number of sectors to read.
* The range can be from 1 to 256.
* @param BufferPtr is a pointer to a buffer where the data will be
* stored. The user must ensure it is big enough to hold
* (512 * NumSectors) bytes.
*
* @return
* - XST_SUCCESS if the read was successful. In interrupt mode,
* this does not mean the read is complete, only that it has begun.
* An event is returned to the user when the read is complete.
* - XST_SYSACE_NO_LOCK if no MPU lock has yet been granted
* - XST_DEVICE_BUSY if the ACE controller is not ready for a
* command
* - XST_FAILURE if an error occurred during the read. The user
* should call XSysAce_GetErrors() to determine the cause of the
* error.
*
* @note None.
*
* @internal
*
* Polled mode is blocking under the assumption that a single sector can be
* transferred at a very fast rate (>20 Mbps). So, the user can choose to
* transfer only single sectors when in polled mode, thus allowing time for
* other work to be done. The biggest issue is that although data transfer
* rates are high, seek time for CompactFlash cards is slow (5-20 ms on
* average, depending on the type of device). We could move to a non-blocking
* solution that transfers 32 bytes at a time (the entire data buffer) and
* then returns. The user would then need to increment its buffer pointer
* appropriately and call the read/write again. The driver would need some way
* to know not to issue a new command to the CompactFlash, but instead continue
* with the previous command. This can be done either with a NumSectors argument
* of zero to indicate that there is already an operation in progress, or by
* having the driver keep state to know there is an operation in progress. The
* interface for either seems a bit awkward. Also, the hit for seek time needs
* to be taken regardless of the blocking or non-blocking nature of the call, so
* the additional few microseconds to transfer a sector of data seems acceptable.
*
******************************************************************************/
int XSysAce_SectorRead(XSysAce *InstancePtr, u32 StartSector,
int NumSectors, u8 *BufferPtr)
{
u16 SectorCmd;
int BytesToRecv;
Xil_AssertNonvoid(InstancePtr != NULL);
Xil_AssertNonvoid(NumSectors > 0 &&
NumSectors <= (XSA_SCCR_COUNT_MASK + 1));
Xil_AssertNonvoid(BufferPtr != NULL);
Xil_AssertNonvoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
/* If a lock has not been granted, return an error */
if (!XSysAce_IsMpuLocked(InstancePtr->BaseAddress)) {
return XST_SYSACE_NO_LOCK;
}
/* See if the CF is ready for a command */
if (!XSysAce_IsReadyForCmd(InstancePtr->BaseAddress)) {
return XST_DEVICE_BUSY;
}
BytesToRecv = XSA_CF_SECTOR_SIZE * NumSectors;
/*
* If in interrupt mode, set up the state variables and enable the
* data-buffer-ready interrupt. This needs to be done before the command
* is sent to the ACE, which will cause the interrupt to occur.
*/
if (XSysAce_IsIntrEnabled(InstancePtr->BaseAddress)) {
InstancePtr->NumRequested = BytesToRecv;
InstancePtr->NumRemaining = BytesToRecv;
InstancePtr->BufferPtr = BufferPtr;
XSysAce_OrControlReg(InstancePtr->BaseAddress,
XSA_CR_DATARDYIRQ_MASK);
}
/* Write the sector ID (LBA) */
XSysAce_RegWrite32(InstancePtr->BaseAddress + XSA_MLR_OFFSET,
StartSector);
/*
* Send the read command for the number of sectors specified
*/
SectorCmd = (NumSectors & XSA_SCCR_COUNT_MASK) | XSA_SCCR_READDATA_MASK;
XSysAce_RegWrite16(InstancePtr->BaseAddress + XSA_SCCR_OFFSET,
SectorCmd);
/*
* If in polled mode, receive the entire amount requested
*/
if (!XSysAce_IsIntrEnabled(InstancePtr->BaseAddress)) {
int NumRead;
/* Reset configuration controller (be sure to keep the lock) */
/* This breaks mvl, beware! */
/*XSysAce_OrControlReg(InstancePtr->BaseAddress, XSA_CR_CFGRESET_MASK); */
NumRead = XSysAce_ReadDataBuffer(InstancePtr->BaseAddress,
BufferPtr, BytesToRecv);
/* Clear reset of configuration controller */
/* This breaks mvl, beware! */
/*XSysAce_AndControlReg(InstancePtr->BaseAddress, ~(XSA_CR_CFGRESET_MASK)); */
if (NumRead != BytesToRecv) {
/* an error occurred, report this to the user */
return XST_FAILURE;
}
}
return XST_SUCCESS;
}
/**
*
* Identify the CompactFlash device. Retrieves the parameters for the
* CompactFlash storage device. Note that this is a polled read of one sector
* of data. The data is read from the CompactFlash into a byte buffer, which
* is then copied into the XSysAce_CFParameters structure passed in by the
* user. The copy is necessary since we don't know how the compiler packs
* the XSysAce_CFParameters structure.
*
* An MPU lock, obtained using XSysAce_Lock(), must be granted before calling
* this function. If a lock has not been granted, no action is taken and an
* error is returned.
*
* @param InstancePtr is a pointer to the XSysAce instance .
* @param ParamPtr is a pointer to a XSysAce_CFParameters structure where
* the information for the CompactFlash device will be stored. See
* xsysace.h for details on the XSysAce_CFParameters structure.
*
* @return
* - XST_SUCCESS if the identify was done successfully
* - XST_FAILURE if an error occurs. Use XSysAce_GetErrors() to
* determine cause.
* - XST_SYSACE_NO_LOCK if no MPU lock has yet been granted
* - XST_DEVICE_BUSY if the CompactFlash is not ready for a command
*
* @note None.
*
* @internal
*
* The identify command has the same protocol as the read sector command
* according to the CompactFlash specification. However, there is a discepency
* in that same specification on the size of the parameter structure. The word
* addresses defined in the spec indicate the parameter information is a full
* 512 bytes, the same size as a sector. The total bytes defined in the spec,
* however, indicate that the parameter information is only 500 bytes. We
* defined the parameter structure in xsysace.h assuming the parameters are the
* full 512 bytes since that makes sense, and therefore ignored the "Total
* Bytes" column in the spec.
*
* The SectorData variable was made static to avoid putting 512 bytes on the
* stack every time this function is called.
*
******************************************************************************/
int XSysAce_IdentifyCF(XSysAce *InstancePtr, XSysAce_CFParameters * ParamPtr)
{
int NumRead;
u32 InterruptsOn;
static u8 SectorData[XSA_CF_SECTOR_SIZE];
Xil_AssertNonvoid(InstancePtr != NULL);
Xil_AssertNonvoid(ParamPtr != NULL);
Xil_AssertNonvoid(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);
/* If a lock has not been granted, return an error */
if (!XSysAce_IsMpuLocked(InstancePtr->BaseAddress)) {
return XST_SYSACE_NO_LOCK;
}
/* See if the CF is ready for a command */
if (!XSysAce_IsReadyForCmd(InstancePtr->BaseAddress)) {
return XST_DEVICE_BUSY;
}
/*
* If interrupts are enabled, we disable them because we want to do this
* identify in polled mode - due to the buffer endian conversion and copy
* that takes place.
*/
InterruptsOn = XSysAce_IsIntrEnabled(InstancePtr->BaseAddress);
if (InterruptsOn) {
XSysAce_DisableInterrupt(InstancePtr);
}
/*
* Send the identify command
*/
XSysAce_RegWrite16(InstancePtr->BaseAddress + XSA_SCCR_OFFSET,
XSA_SCCR_IDENTIFY_MASK);
/* Reset configuration controller (be sure to keep the lock) */
/* This breaks mvl, beware! */
/* XSysAce_OrControlReg(InstancePtr->BaseAddress, XSA_CR_CFGRESET_MASK); */
/*
* Read a sector of data from the data buffer. The parameter info is
* the same size as a sector.
*/
NumRead = XSysAce_ReadDataBuffer(InstancePtr->BaseAddress, SectorData,
XSA_CF_SECTOR_SIZE);
/* Clear reset of configuration controller */
/* This breaks mvl, beware! */
/*XSysAce_AndControlReg(InstancePtr->BaseAddress, ~(XSA_CR_CFGRESET_MASK)); */
/* If interrupts were on, re-enable interrupts (regardless of error) */
if (InterruptsOn) {
XSysAce_EnableInterrupt(InstancePtr);
}
if (NumRead == 0) {
/* an error occurred */
return XST_FAILURE;
}
/*
* Copy the byte buffer to the parameter structure
*/
FillParam(ParamPtr, SectorData);
return XST_SUCCESS;
}
