FreeCalypso > hg > fc-tourmaline

view src/gpf/ccd/bitfun.h @ 220:0ed36de51973

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
ABB semaphore protection overhaul The ABB semaphone protection logic that came with TCS211 from TI was broken in several ways: * Some semaphore-protected functions were called from Application_Initialize() context. NU_Obtain_Semaphore() called with NU_SUSPEND fails with NU_INVALID_SUSPEND in this context, but the return value wasn't checked, and NU_Release_Semaphore() would be called unconditionally at the end. The latter call would increment the semaphore count past 1, making the semaphore no longer binary and thus no longer effective for resource protection. The fix is to check the return value from NU_Obtain_Semaphore() and skip the NU_Release_Semaphore() call if the semaphore wasn't properly obtained. * Some SPI hardware manipulation was being done before entering the semaphore- protected critical section. The fix is to reorder the code: first obtain the semaphore, then do everything else. * In the corner case of L1/DSP recovery, l1_abb_power_on() would call some non-semaphore-protected ABB & SPI init functions. The fix is to skip those calls in the case of recovery. * A few additional corner cases existed, all of which are fixed by making ABB semaphore protection 100% consistent for all ABB functions and code paths. There is still one remaining problem of priority inversion: suppose a low- priority task calls an ABB function, and some medium-priority task just happens to preempt right in the middle of that semaphore-protected ABB operation. Then the high-priority SPI task is locked out for a non-deterministic time until that medium-priority task finishes its work and goes back to sleep. This priority inversion problem remains outstanding for now.
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 26 Apr 2021 20:55:25 +0000
parents 4e78acac3d88
children
line wrap: on
line source

/* 
+----------------------------------------------------------------------------- 
|  Project :  
|  Modul   : bitfun.h
+----------------------------------------------------------------------------- 
|  Copyright 2002 Texas Instruments Berlin, AG 
|                 All rights reserved. 
| 
|                 This file is confidential and a trade secret of Texas 
|                 Instruments Berlin, AG 
|                 The receipt of or possession of this file does not convey 
|                 any rights to reproduce or disclose its contents or to 
|                 manufacture, use, or sell anything it may describe, in 
|                 whole, or in part, without the specific written consent of 
|                 Texas Instruments Berlin, AG. 
+----------------------------------------------------------------------------- 
|  Purpose :  Condat Coder Decoder
|             Prototypes of the elementary bit manipulation functions
+----------------------------------------------------------------------------- 
*/ 


#ifndef __BITFUN
#define __BITFUN


#ifndef __BITFUN_C__

EXTERN void   bf_writePadBits      (T_CCD_Globs *globs);
EXTERN void   bf_writeVal          (ULONG value, ULONG bSize, T_CCD_Globs *globs);
EXTERN ULONG  bf_getBits           (ULONG  len, T_CCD_Globs *globs);
EXTERN void   bf_writeBitStr_PER   (USHORT len, T_CCD_Globs *globs);
EXTERN void   bf_readBitStr_PER    (USHORT len, T_CCD_Globs *globs);
EXTERN void   bf_writeBits         (ULONG  len, T_CCD_Globs *globs);
EXTERN void   bf_readBits          (ULONG  len, T_CCD_Globs *globs);
EXTERN void   bf_writeBitChunk     (ULONG  len, T_CCD_Globs *globs);
EXTERN void   bf_readBitChunk      (ULONG  len, T_CCD_Globs *globs);
EXTERN BOOL   bf_readBit           (T_CCD_Globs *globs);
EXTERN void   bf_writeBit          (BOOL Bit, T_CCD_Globs *globs);
EXTERN UBYTE  bf_decodeByteNumber  (const ULONG len, T_CCD_Globs *globs);
EXTERN ULONG  bf_decodeShortNumber (const ULONG len, T_CCD_Globs *globs);
EXTERN ULONG  bf_decodeLongNumber  (UBYTE len, T_CCD_Globs *globs);
EXTERN void   bf_codeShortNumber   (UBYTE len, USHORT val, T_CCD_Globs *globs);
EXTERN void   bf_codeByteNumber    (UBYTE len, UBYTE val, T_CCD_Globs *globs);
EXTERN void   bf_codeLongNumber    (UBYTE len, ULONG val, T_CCD_Globs *globs);
EXTERN void   bf_recodeShortNumber (USHORT pos, UBYTE len, USHORT val, T_CCD_Globs *globs);
EXTERN void   bf_recodeByteNumber  (USHORT pos, UBYTE len, UBYTE  val, T_CCD_Globs *globs);
EXTERN void   bf_recodeBit         (USHORT pos, UBYTE Bit, T_CCD_Globs *globs);
EXTERN void   bf_rShift8Bit        (USHORT srcBitPos, USHORT bitLen, T_CCD_Globs *globs);

#endif /* __BITFUN_C__ */

/* a Macro for incrementing the position in the bitbuffer         */
/* _bitpos, _bytepos and _byteoffs are recalculated               */

#define bf_incBitpos(A, globs) globs->bitpos = (USHORT)(globs->bitpos+(A));\
                        globs->bytepos = (USHORT)(globs->bitpos >> 3);\
                        globs->byteoffs = (UBYTE)(globs->bitpos & 7)
#define bf_setBitpos(A, globs) globs->bitpos = (USHORT)(A);\
                        globs->bytepos = (USHORT)(globs->bitpos >> 3);\
                        globs->byteoffs = (UBYTE)(globs->bitpos & 7)

/*
 * end of bitstream if we can not read almost 4 bits
 */
#define bf_endOfBitstream(globs) (globs->bitpos >= globs->maxBitpos)

#endif