FreeCalypso > hg > fc-tourmaline
view src/gpf/ccd/asn1_objid.c @ 220:0ed36de51973
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 |
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/* +------------------------------------------------------------------------------ | File: asn1_objid.c +------------------------------------------------------------------------------ | 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: Encoding and decoding functions for ASN1_OBJ_ID type | | $Identity:$ +------------------------------------------------------------------------------ */ /* * Standard definitions like UCHAR, ERROR etc. */ #include "typedefs.h" #include "header.h" /* * Prototypes of ccd (USE_DRIVER EQ undef) for prototypes only * look at ccdapi.h */ #undef USE_DRIVER #include "ccdapi.h" /* * Types and functions for bit access and manipulation */ #include "ccd_globs.h" #include "bitfun.h" /* * Prototypes and constants in the common part of ccd */ #include "ccd.h" /* * Declaration of coder/decoder tables */ #include "ccdtable.h" #include "ccddata.h" #ifndef RUN_INT_RAM /* +------------------------------------------------------------------------+ | PROJECT : CCD (6144) MODULE : asn1_objid | | STATE : code ROUTINE : cdc_asn1_obj_id_decode | +------------------------------------------------------------------------+ PURPOSE : Decode PER OBJECT IDENTIFIER type The PER encoding of an object identifier type uses the content octets of BER preceded by a length determinant that will in practice be a single octet. */ SHORT cdc_asn1_obj_id_decode (const ULONG c_ref, const ULONG e_ref, T_CCD_Globs *globs) { U8 BER_Len; #ifdef DEBUG_CCD #ifndef CCD_SYMBOLS TRACE_CCD (globs, "cdc_asn1_obj_id_decode()"); #else TRACE_CCD (globs, "cdc_asn1_obj_id_decode() %s", mcomp[melem[e_ref].elemRef].name); #endif #endif globs->pstructOffs = melem[e_ref].structOffs; /* For optional elements we have already set the valid flag in the * C-structure. We have done it while processing ASN1_SEQ. */ if ( ! cdc_isPresent(e_ref, globs) ) { return 1; } /* * Skip over PER length octet and BER tag octet. */ bf_incBitpos (16, globs); /* * For unknown extension read the length and skip over the octets. */ BER_Len = (U8) bf_getBits (8, globs); *(U8 *)(globs->pstruct + globs->pstructOffs++) = BER_Len; /* * Copy the content of object identifier bytes into the C-Structure. */ #ifdef _TMS470 bf_incBitpos (8 * BER_Len, globs); #else { int i; for (i=0; i < BER_Len; i++) *(U8 *)(globs->pstruct + globs->pstructOffs++) = (U8) bf_getBits (8, globs); } #endif return 1; } #endif /* !RUN_INT_RAM */ #ifndef RUN_INT_RAM /* +------------------------------------------------------------------------+ | PROJECT : CCD (6144) MODULE : asn1_objid | | STATE : code ROUTINE : cdc_asn1_obj_id_encode | +------------------------------------------------------------------------+ PURPOSE : Encode PER OBJECT IDENTIFIER type The PER encoding of an object identifier type uses the content octets of BER preceded by a length determinant that will in practice be a single octet. */ SHORT cdc_asn1_obj_id_encode (const ULONG c_ref, const ULONG e_ref, T_CCD_Globs *globs) { #ifdef DEBUG_CCD #ifndef CCD_SYMBOLS TRACE_CCD (globs, "cdc_asn1_obj_id_encode()"); #else TRACE_CCD (globs, "cdc_asn1_obj_id_encode() %s", mcomp[melem[e_ref].elemRef].name); #endif #endif return 1; } #endif /* !RUN_INT_RAM */
