/*********************************************************************
* @fn initNV
*
* @brief Initialize the NV flash pages.
*
* @param none
*
* @return TRUE
*/
static uint8 initNV( void )
{
osalNvPgHdr_t pgHdr;
uint8 oldPg = OSAL_NV_PAGE_NULL;
uint8 newPg = OSAL_NV_PAGE_NULL;
uint8 findDups = FALSE;
uint8 pg;
pgRes = OSAL_NV_PAGE_NULL;
for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
{
HalFlashRead(pg, OSAL_NV_PAGE_HDR_OFFSET, (uint8 *)(&pgHdr), OSAL_NV_HDR_SIZE);
if ( pgHdr.active == OSAL_NV_ERASED_ID )
{
if ( pgRes == OSAL_NV_PAGE_NULL )
{
pgRes = pg;
}
else
{
setPageUse( pg, TRUE );
}
}
else // Page is active.
{
// If the page is not yet in use, it is the tgt of items from an xfer.
if ( pgHdr.inUse == OSAL_NV_ERASED_ID )
{
newPg = pg;
}
// An Xfer from this page was in progress.
else if ( pgHdr.xfer != OSAL_NV_ERASED_ID )
{
oldPg = pg;
}
}
// Calculate page offset and lost bytes - any "old" item triggers an N^2 re-scan from start.
if ( initPage( pg, OSAL_NV_ITEM_NULL, findDups ) != OSAL_NV_ITEM_NULL )
{
findDups = TRUE;
pg = OSAL_NV_PAGE_BEG-1;
continue;
}
} // for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
/* First the old page is erased, and then the new page is put into use.
* So if a transfer was in progress, the new page will always not yet be
* marked as in use, since that is the last step to ending a transfer.
*/
if ( newPg != OSAL_NV_PAGE_NULL )
{
/* If there is already a fallow page reserved, keep it and put the newPg in use.
* An unfinished compaction will finish to the new reserve page and the old page
* will be erased and reserved.
*/
if ( pgRes != OSAL_NV_PAGE_NULL )
{
setPageUse( newPg, TRUE );
}
/* If setting old page to 'xfer' failed or board reset before it was effected, there is no way
* to know which page was the 'old page' - so just reset all NV pages to start clean.
*/
else if ( oldPg != OSAL_NV_PAGE_NULL )
{
pgRes = newPg;
}
/* If a page compaction was interrupted and the page being compacted is not
* yet erased, then there may be items remaining to xfer before erasing.
*/
if ( oldPg != OSAL_NV_PAGE_NULL )
{
compactPage( oldPg );
}
}
/* If no page met the criteria to be the reserve page:
* - A compactPage() failed or board reset before doing so.
* - Perhaps the user changed which Flash pages are dedicated to NV and downloaded the code
* without erasing Flash?
*/
if ( pgRes == OSAL_NV_PAGE_NULL )
{
for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
{
erasePage( pg );
}
initNV();
}
return TRUE;
}
/*********************************************************************
* @fn compactPage
*
* @brief Compacts the page specified.
*
* @param srcPg - Valid NV page to erase.
*
* @return none
*/
static void compactPage( uint8 srcPg )
{
uint16 dstOff = pgOff[pgRes-OSAL_NV_PAGE_BEG];
uint16 srcOff = OSAL_NV_ZEROED_ID;
osalNvHdr_t hdr;
// Mark page as being in process of compaction.
writeWordH( srcPg, OSAL_NV_PG_XFER, (uint8*)(&srcOff) );
srcOff = OSAL_NV_PAGE_HDR_SIZE;
do
{
uint16 sz;
HalFlashRead(srcPg, srcOff, (uint8 *)(&hdr), OSAL_NV_HDR_SIZE);
if ( hdr.id == OSAL_NV_ERASED_ID )
{
break;
}
srcOff += OSAL_NV_HDR_SIZE;
if ( (srcOff + hdr.len) > OSAL_NV_PAGE_FREE )
{
break;
}
sz = OSAL_NV_DATA_SIZE( hdr.len );
if ( hdr.id != OSAL_NV_ZEROED_ID )
{
if ( hdr.chk == calcChkF( srcPg, srcOff, hdr.len ) )
{
setItem( srcPg, srcOff, eNvXfer );
writeBuf( pgRes, dstOff, OSAL_NV_HDR_SIZE, (byte *)(&hdr) );
dstOff += OSAL_NV_HDR_SIZE;
xferBuf( srcPg, srcOff, pgRes, dstOff, sz );
dstOff += sz;
}
setItem( srcPg, srcOff, eNvZero ); // Mark old location as invalid.
}
srcOff += sz;
} while ( TRUE );
pgOff[pgRes-OSAL_NV_PAGE_BEG] = dstOff;
/* In order to recover from a page compaction that is interrupted,
* the logic in osal_nv_init() depends upon the following order:
* 1. Compacted page is erased.
* 2. State of the target of compaction is changed ePgActive to ePgInUse.
*/
erasePage( srcPg );
// Mark the reserve page as being in use.
setPageUse( pgRes, TRUE );
// Set the reserve page to be the newly erased page.
pgRes = srcPg;
}
/*********************************************************************
* @fn initNV
*
* @brief Initialize the NV flash pages.
*
* @param none
*
* @return TRUE
*/
static uint8 initNV( void )
{
osalNvPgHdr_t pgHdr;
uint8 oldPg = OSAL_NV_PAGE_NULL;
uint8 findDups = FALSE;
uint8 pg;
pgRes = OSAL_NV_PAGE_NULL;
for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
{
HalFlashRead(pg, OSAL_NV_PAGE_HDR_OFFSET, (uint8 *)(&pgHdr), OSAL_NV_HDR_SIZE);
if ( pgHdr.active == OSAL_NV_ERASED_ID )
{
if ( pgRes == OSAL_NV_PAGE_NULL )
{
pgRes = pg;
}
else
{
setPageUse( pg, TRUE );
}
}
// An Xfer from this page was in progress.
else if ( pgHdr.xfer != OSAL_NV_ERASED_ID )
{
oldPg = pg;
}
}
// If a page compaction was interrupted before the old page was erased.
if ( oldPg != OSAL_NV_PAGE_NULL )
{
/* Interrupted compaction before the target of compaction was put in use;
* so erase the target of compaction and start again.
*/
if ( pgRes != OSAL_NV_PAGE_NULL )
{
erasePage( pgRes );
(void)compactPage( oldPg, OSAL_NV_ITEM_NULL );
}
/* Interrupted compaction after the target of compaction was put in use,
* but before the old page was erased; so erase it now and create a new reserve page.
*/
else
{
erasePage( oldPg );
pgRes = oldPg;
}
}
else if ( pgRes != OSAL_NV_PAGE_NULL )
{
erasePage( pgRes ); // The last page erase could have been interrupted by a power-cycle.
}
/* else if there is no reserve page, COMPACT_PAGE_CLEANUP() must have succeeded to put the old
* reserve page (i.e. the target of the compacted items) into use but got interrupted by a reset
* while trying to erase the page to be compacted. Such a page should only contain duplicate items
* (i.e. all items will be marked 'Xfer') and thus should have the lost count equal to the page
* size less the page header.
*/
for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
{
// Calculate page offset and lost bytes - any "old" item triggers an N^2 re-scan from start.
if ( initPage( pg, OSAL_NV_ITEM_NULL, findDups ) != OSAL_NV_ITEM_NULL )
{
findDups = TRUE;
pg = (OSAL_NV_PAGE_BEG - 1); // Pre-decrement so that loop increment will start over at zero.
continue;
}
}
if (findDups)
{
// Final pass to calculate page lost after invalidating duplicate items.
for ( pg = OSAL_NV_PAGE_BEG; pg <= OSAL_NV_PAGE_END; pg++ )
{
(void)initPage( pg, OSAL_NV_ITEM_NULL, FALSE );
}
}
if ( pgRes == OSAL_NV_PAGE_NULL )
{
uint8 idx, mostLost = 0;
for ( idx = 0; idx < OSAL_NV_PAGES_USED; idx++ )
{
// Is this the page that was compacted?
if (pgLost[idx] == (OSAL_NV_PAGE_SIZE - OSAL_NV_PAGE_HDR_SIZE))
{
mostLost = idx;
break;
}
/* This check is not expected to be necessary because the above test should always succeed
* with an early loop exit.
*/
else if (pgLost[idx] > pgLost[mostLost])
{
mostLost = idx;
}
}
pgRes = mostLost + OSAL_NV_PAGE_BEG;
erasePage( pgRes ); // The last page erase had been interrupted by a power-cycle.
}
return TRUE;
}
