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view src/g23m-gsm/alr2/alr_gprs.h @ 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 | 3a14ee9a9843 |
| children |
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/* +----------------------------------------------------------------------------- | Project : | Modul : J:\g23m-gsm\alr\alr_gprs.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 : +----------------------------------------------------------------------------- */ typedef struct { UBYTE v_ptmsi; ULONG ptmsi; UBYTE v_ptmsi2; ULONG ptmsi2; UBYTE ign_pgm; UBYTE pbcch; UBYTE check_bsic; UBYTE ptm; UBYTE pim; UBYTE sync_only; UBYTE pcco_active; } T_ALR_GPRS_DATA; #define SI13_ON_NBCCH 0 #define SI13_ON_EBCCH 1 void gprs_alr_get_table (const T_FUNC** tab, USHORT* n); void gprs_alr_mon_ctrl_req (T_MPH_MON_CTRL_REQ* ctrl_req); BOOL gprs_alr_check_packet_paging (UBYTE* frame, UBYTE which); BOOL gprs_alr_check_packet_paging_2(UBYTE* frame, UBYTE which); BOOL gprs_alr_check_ptmsi (ULONG ptmsi_pag); void gprs_alr_store_ptmsi (UBYTE indic, ULONG tmsi); void gprs_alr_store_ptmsi2 (UBYTE indic2, ULONG tmsi2); void gprs_alr_check_downlink_assign(T_MPHC_DATA_IND* data_ind); void gprs_alr_init (void); BOOL gprs_check_read_si13_only (UBYTE si13_position); void gprs_check_page_mode (T_MPHC_DATA_IND* data_ind); void set_gprs_support( UBYTE support ); GLOBAL BOOL gprs_alr_is_supported (void);