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view src/g23m-aci/gdd_dio/gdd_dio_data.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 | fa8dc04885d8 |
children |
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/* +------------------------------------------------------------------------------ | File: gdd_dio_data.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 : Internal data structures for entity gdd_dio (DIO BAT Adapter) +----------------------------------------------------------------------------- */ #ifndef GDD_DIO_DATA_H #define GDD_DIO_DATA_H /*==== INCLUDES =============================================================*/ /* DIO stuff */ #include "dio.h" /* for T_DIO_CAP_PKT */ /* We must define P_DIO_H, in order to avoid inclusion of p_dio.h. This is necessary due to the special fact, that "dio.h", which is included in the header "dio_io/dio_drv.h", mirrors the header "p_dio.h". */ #define P_DIO_H #include "gdd.h" #include "gdd_dio_queue.h" /* for T_GDD_BUF_QUEUE */ /*==== DEFINITIONS ==========================================================*/ #define GDD_CON_HANDLE_USER_MASK 0xFF000000 /*==== CONSTS ===============================================================*/ /*==== TYPES =================================================================*/ /** * States of kernel service */ typedef enum { GDD_DIO_KER_DEAD = 0, GDD_DIO_KER_INIT, GDD_DIO_KER_READY } T_GDD_DIO_KER_STATE; /** * Kernel service data */ typedef struct { T_GDD_DIO_KER_STATE state; } T_GDD_DIO_KER_DATA; /** * States of a single connection */ typedef enum { GDD_DIO_CON_DEAD = 1, GDD_DIO_CON_CONNECT, GDD_DIO_CON_READY, GDD_DIO_CON_SENDING, GDD_DIO_CON_CLOSE } T_GDD_DIO_CON_STATE; /** * Connection data */ typedef struct { T_GDD_BUF_QUEUE rx_queue; /* RX buffer queue */ T_GDD_BUF_QUEUE tx_queue; /* TX buffer queue */ UBYTE con_state; /* Connection state */ UBYTE wait_send_buf; /* Flag indicating that we wait for a send buffer */ U32 dio_device; /* Dio device type */ T_GDD_RECEIVE_DATA_CB rcv_cb; /* Receive callback of the client */ T_GDD_SIGNAL_CB sig_cb; /* Signale callback of the client */ T_DIO_CAP_PKT dio_cap; /* DIO capabilities */ } T_GDD_DIO_CON_DATA; /** * DIO driver number */ typedef U32 T_GDD_DIO_DRV_NUM; /*==== EXPORTS ===============================================================*/ int inst_num_from_dev_id(U32 device); #endif /* !GDD_DIO_DATA_H */