FreeCalypso > hg > fc-tourmaline
view src/g23m-gsm/cc/cc_srv.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 | fa8dc04885d8 |
children |
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/* +----------------------------------------------------------------------------- | Project : GSM-PS (6147) | Modul : CC_SRV +----------------------------------------------------------------------------- | 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 : This Modul defines the functions for the common | services of the component CC of the mobile station. +----------------------------------------------------------------------------- */ #ifndef CC_SRV_C #define CC_SRV_C #define ENTITY_CC /*==== INCLUDES ===================================================*/ #include <string.h> #include "typedefs.h" #include "pcm.h" #include "vsi.h" #include "custom.h" #include "gsm.h" #include "message.h" #include "ccdapi.h" #include "prim.h" #include "cus_cc.h" #include "cnf_cc.h" #include "mon_cc.h" #include "pei.h" #include "tok.h" #include "cc.h" /*==== EXPORT =====================================================*/ /*==== PRIVAT =====================================================*/ /*==== VARIABLES ==================================================*/ /*==== FUNCTIONS ==================================================*/ /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_SRV | | STATE : code ROUTINE : srv_convert_ti | +--------------------------------------------------------------------+ PURPOSE : Converts the transaction identifier to an index in the call data. */ GLOBAL UBYTE srv_convert_ti (UBYTE ti) { GET_INSTANCE_DATA; UBYTE i; TRACE_FUNCTION ("srv_convert_ti()"); for (i=0;i<MAX_CC_CALLS;i++) if (cc_data->stored_ti_values[i] EQ ti) { cc_data->ti = ti; return i; } return NOT_PRESENT_8BIT; } /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_SRV | | STATE : code ROUTINE : srv_define_ti | +--------------------------------------------------------------------+ PURPOSE : Allocates a free entry in the call data. */ GLOBAL UBYTE srv_define_ti (void) { GET_INSTANCE_DATA; UBYTE i; TRACE_FUNCTION ("srv_define_ti()"); for (i=0;i<MAX_CC_CALLS;i++) { if (cc_data->stored_ti_values[i] == NOT_PRESENT_8BIT) { cc_data->stored_ti_values[i] = cc_data->ti; return i; } } return NOT_PRESENT_8BIT; } /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_SRV | | STATE : code ROUTINE : srv_free_ti | +--------------------------------------------------------------------+ PURPOSE : Frees an allocated entry in the call data. */ GLOBAL void srv_free_ti (void) { GET_INSTANCE_DATA; UBYTE i; UBYTE connection_available = FALSE; TRACE_FUNCTION ("srv_free_ti()"); for (i=0;i<MAX_CC_CALLS;i++) { if (cc_data->stored_ti_values[i] EQ cc_data->ti) { cc_data->stored_ti_values[i] = NOT_PRESENT_8BIT; } if (cc_data->stored_ti_values[i] NEQ NOT_PRESENT_8BIT) connection_available = TRUE; } if (connection_available EQ FALSE) cc_data->channel_mode = NAS_CHM_SIG_ONLY; } /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_REL | | STATE : code ROUTINE : srv_free_stored_setup | +--------------------------------------------------------------------+ PURPOSE : Free a stored SETUP or EMERGENCY SETUP message. */ GLOBAL void srv_free_stored_setup (void) { GET_INSTANCE_DATA; TRACE_FUNCTION ("srv_free_stored_setup()"); cc_data->setup_reattempt_ti = NOT_PRESENT_8BIT; if (cc_data->stored_setup NEQ NULL) { PFREE (cc_data->stored_setup); cc_data->stored_setup = NULL; } } /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_SRV | | STATE : code ROUTINE : srv_store_prim | +--------------------------------------------------------------------+ PURPOSE : stores a primitive. */ GLOBAL void srv_store_prim (T_PRIM * prim) { GET_INSTANCE_DATA; #ifdef OPTION_REF cc_data->stored_prim [cc_data->stored_prim_in++] = prim; #else memcpy (&cc_data->stored_prim [cc_data->stored_prim_in++], prim, sizeof (T_PRIM)); #endif if (cc_data->stored_prim_in EQ MAX_STORED_PRIM) cc_data->stored_prim_in = 0; cc_data->stored_prim_write++; } /* +--------------------------------------------------------------------+ | PROJECT : GSM-PS (6147) MODULE : CC_SRV | | STATE : code ROUTINE : srv_use_stored_prim | +--------------------------------------------------------------------+ PURPOSE : Uses all stored primitives. */ GLOBAL void srv_use_stored_prim (void) { GET_INSTANCE_DATA; TRACE_FUNCTION ("srv_use_stored_prim()"); if (cc_data->stored_prim_write > 0) { cc_data->stored_prim_read += cc_data->stored_prim_write; cc_data->stored_prim_write = 0; while (cc_data->stored_prim_read NEQ 0) { T_PRIM * prim; cc_data->stored_prim_read--; #ifdef OPTION_REF prim = cc_data->stored_prim[cc_data->stored_prim_out++]; #else prim = &cc_data->stored_prim[cc_data->stored_prim_out++]; #endif if (cc_data->stored_prim_out EQ MAX_STORED_PRIM) cc_data->stored_prim_out = 0; cc_pei_primitive (prim); } } } #endif