FreeCalypso > hg > fc-tourmaline
view src/g23m-gsm/dl/dl_em.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 : | Modul : +----------------------------------------------------------------------------- | 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 Module defines the engineering mode (EM) device driver for the | G23 protocol stack. This driver is used to control all engineering | mode related functions. +----------------------------------------------------------------------------- */ #ifndef DL_EM_C #define DL_EM_C #define ENTITY_DL /*==== INCLUDES ===================================================*/ #include "typedefs.h" #include <string.h> #include "pconst.cdg" #include "vsi.h" #include "pconst.cdg" #include "custom.h" #include "gsm.h" #include "mon_dl.h" #include "prim.h" #include "pei.h" #include "tok.h" #include "ccdapi.h" #include "dl.h" #include "dl_em.h" #ifdef FF_EM_MODE #ifdef _SIMULATION_ #pragma message("this build includes engineering mode (FF_EM_MODE)") #endif /*==== EXPORT =====================================================*/ /* * These variables are used between entities. Even this is not a clean solution * it is a straigth forward way to reduce the overhead to a minimum. A clean * solution would be based on an only usage of primitives which would stress * the OS without aditional advantage!! */ GLOBAL UBYTE em_dl_sem_buffer [EM_DL_SEM_SIZE]; GLOBAL UBYTE em_dl_sem_index = 0; GLOBAL UBYTE em_dl_sem_read_index = 0; /* Event tracing flags for EM */ GLOBAL BOOL dl_v[EM_MAX_DL_EVENTS]; /*==== PRIVAT =====================================================*/ static T_HANDLE sem_EM_DL; static UBYTE em_dl_trace_occured; #if !defined(INVOKE_SIGNAL) LOCAL UBYTE em_dl_write (UBYTE length, UBYTE * data); LOCAL void dl_em_first_event_check(void);/*for ACI notification of first EM event*/ #endif /* !INVOKE_SIGNAL */ /*==== VARIABLES ==================================================*/ /* +------------------------------------------------------------------------------ | Function : dl_em_buffer_4 +------------------------------------------------------------------------------ | Description : Perform buffer check and store corresponding data in it. | | Parameters : Event number, data value1, data value2 | | Return : TRUE/FALSE | +------------------------------------------------------------------------------ */ GLOBAL UBYTE em_write_buffer_4 (UBYTE event_no, UBYTE value1, UBYTE value2) { #define THIS_EM_BUFFER_LEN 4 UBYTE em_dl_event_buffer[THIS_EM_BUFFER_LEN]; TRACE_EVENT_WIN ("em_write_buffer_4"); /* ACI is informed about the first event trace, used for later data processing. */ dl_em_first_event_check(); em_dl_event_buffer[0] = event_no; /* Event number */ em_dl_event_buffer[1] = THIS_EM_BUFFER_LEN-2; /* Value length - 0 equals no data */ em_dl_event_buffer[2] = value1; /* first data info */ em_dl_event_buffer[3] = value2; /* second data info */ return ( em_dl_write (THIS_EM_BUFFER_LEN, em_dl_event_buffer) ); /* Data is stored inside buffer, reset flag */ #undef THIS_EM_BUFFER_LEN } /* +------------------------------------------------------------------------------ | Function : dl_em_write_buffer_5a +------------------------------------------------------------------------------ | Description : Perform buffer check and store corresponding data in it. | | Parameters : Event number, data value1, data value2, data cs (USHORT) | | Return : TRUE/FALSE | +------------------------------------------------------------------------------ */ GLOBAL UBYTE em_write_buffer_5a (UBYTE event_no, UBYTE value1, UBYTE value2, USHORT cs) { #define THIS_EM_BUFFER_LEN 6 UBYTE em_dl_event_buffer[THIS_EM_BUFFER_LEN]; TRACE_EVENT_WIN ("em_write_buffer_5a"); /* ACI is informed about the first event trace, used for later data processing. */ dl_em_first_event_check(); em_dl_event_buffer[0] = event_no; /* Event number */ em_dl_event_buffer[1] = THIS_EM_BUFFER_LEN-2; /* Value length - 0 equals no data */ em_dl_event_buffer[2] = value1; /* first data info */ em_dl_event_buffer[3] = value2; /* second data info */ em_dl_event_buffer[4] = (UBYTE)(cs >> 8); /* Data to be stored - MSB first */ em_dl_event_buffer[5] = (UBYTE)(cs); /* LSB second */ return ( em_dl_write (THIS_EM_BUFFER_LEN, em_dl_event_buffer) );/* Data is stored inside buffer, reset flag */ #undef THIS_EM_BUFFER_LEN } /* +------------------------------------------------------------------------------ | Function : em_init_dl_event_trace +------------------------------------------------------------------------------ | Description : Initialize the event tracing flags | | Parameters : | | Return : | +------------------------------------------------------------------------------ */ GLOBAL void em_init_dl_event_trace(void) { UBYTE i; TRACE_EVENT_WIN ("em_init_dl_event_trace"); for(i=1; i<EM_MAX_DL_EVENTS; i++) { dl_v[i] = 0; } } /* +------------------------------------------------------------------------------ | Function : dl_em_dl_event_req +------------------------------------------------------------------------------ | Description : Set the event tracing flags according the bitmask | | Parameters : Primitive - Bitmask | | Return : | +------------------------------------------------------------------------------ */ GLOBAL void dl_em_dl_event_req (T_EM_DL_EVENT_REQ *em_dl_event_req) { UBYTE i; TRACE_EVENT_WIN_P1 ("dl_em_dl_event_req: bitmask_dl=%x", em_dl_event_req->bitmask_dl); /* * The event tracing flags are set according the bitmask. dl_v[i] are * the flags belonging to the event number described in 8443.601 */ for(i=1; i<EM_MAX_DL_EVENTS; i++) { dl_v[i] = ((em_dl_event_req->bitmask_dl & (0x01<<(i-1))) > 0) ? TRUE : FALSE; } /* A new event trace is generated therefor the flag is set to 0. */ em_dl_trace_occured = 0; PFREE(em_dl_event_req); } LOCAL void em_dl_sem_clear (void) { ENTER_CRITICAL_SECTION (sem_EM_DL); em_dl_sem_index = em_dl_sem_read_index = 0; LEAVE_CRITICAL_SECTION (sem_EM_DL); SYST_TRACE ("DL:em_dl_sem_index cleared"); } GLOBAL void em_dl_sem_init (void) { sem_EM_DL = vsi_s_open (VSI_CALLER "EM_DL_SEM",1); if (sem_EM_DL NEQ VSI_ERROR) { em_dl_sem_clear (); } else { SYST_TRACE ("DL:canīt open semaphore \"EM_DL_SEM\""); } em_dl_trace_occured = 0; } GLOBAL void em_dl_sem_exit (void) { if (sem_EM_DL NEQ VSI_ERROR) vsi_s_close (VSI_CALLER sem_EM_DL); } /* To be able to read the dl-buffer from aci, em_dl_sem_read occupies the semaphor with ENTER_CRITICAL_SECTION. After read process toke place the function em_dl_sem_clear must be called to open the semaphor again and reset the read index. */ GLOBAL void em_dl_sem_reset (void) { /* ENTER_CRITICAL_SECTION (sem_EM_DL); */ em_dl_sem_index = em_dl_sem_read_index = 0; LEAVE_CRITICAL_SECTION (sem_EM_DL); SYST_TRACE ("DL:em_dl_sem_index reseted"); } GLOBAL void em_dl_sem_read (void) { USHORT semCount; TRACE_EVENT_WIN ( "em_dl_sem_read"); if (vsi_s_status (VSI_CALLER sem_EM_DL, &semCount) NEQ VSI_OK) { com_semaphore_err(); return ; } if (semCount EQ 0) { SYST_TRACE ("DL:semCount == 0"); return ; } ENTER_CRITICAL_SECTION (sem_EM_DL); /* The dl semaphor will be read by the engineering mode via aci, therefore the functions em_dl_sem_read and em_dl_sem_reset are defined as global. To ensure that during reading only aci has access to the semaphor the macro LEAVE_CRITICAL_SECTION is called after the read process toke place - in the em_dl_sem_reset function. */ } /* Return value TRUE/FALSE - TRUE keeps the event flag valid, FALSE indicates a successful flag handle */ #if defined(INVOKE_SIGNAL) GLOBAL UBYTE em_dl_write (UBYTE length, UBYTE *data) #else /* INVOKE_SIGNAL */ LOCAL UBYTE em_dl_write (UBYTE length, UBYTE *data) #endif /* INVOKE_SIGNAL */ { USHORT semCount; GET_INSTANCE_DATA; TRACE_EVENT_WIN ("em_dl_write"); if (dl_data->interrupt_context) { sig_invoke_dl_em_write (length, data); return FALSE; } if (vsi_s_status (VSI_CALLER sem_EM_DL, &semCount) NEQ VSI_OK) { com_semaphore_err(); return TRUE; } if (semCount EQ 0) { TRACE_EVENT_WIN ("semCount == 0"); return TRUE; } /* * buffer overflow protection - EM_DL_SEM_SIZE = 30 */ if ( (em_dl_sem_index + length) > EM_DL_SEM_SIZE ) { TRACE_EVENT_WIN ("dl em buffer full"); return FALSE; } if (com_enter_critical_section (sem_EM_DL)) return TRUE; memcpy (&em_dl_sem_buffer[em_dl_sem_index], data, length); em_dl_sem_index += length; com_leave_critical_section (sem_EM_DL); return FALSE; /* indicates that flag was handled */ } /* endfunc em_dl_write */ /* +------------------------------------------------------------------------------ | Function : dl_em_first_event_check() +------------------------------------------------------------------------------ | Description : Checks if first EM-Event ocured | | Parameters : None | | Return : None | +------------------------------------------------------------------------------ */ /* ACI is informed about the first event trace, used for later data processing. */ #if defined(INVOKE_SIGNAL) GLOBAL void dl_em_first_event_check(void) #else LOCAL void dl_em_first_event_check(void) #endif /* !INVOKE_SIGNAL */ { if(!em_dl_trace_occured) { #if defined(INVOKE_SIGNAL) GET_INSTANCE_DATA; if (dl_data->interrupt_context) { sig_invoke_dl_em_first_event_check (); return; } #endif /* INVOKE_SIGNAL */ TRACE_FUNCTION("dl_em_first_event_check()"); { PALLOC(em_notification, EM_DATA_IND); em_notification->entity = EM_DL; PSENDX(MMI, em_notification); } em_dl_trace_occured++; } } #endif /* FF_EM_MODE */ #endif /* DL_EM_C */