view src/g23m-fad/tcpip/rnet.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
line wrap: on
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/*---------------------------------------------------------------------------
 * Adaption of Riviera Net (RNET) TCP/IP to GPF and DTI2
 *-------------------------------------------------------------------------*/

/* Here we define some dummy Riviera Frame functions
 * so that we can link an executable,
 * only to be sure that we've copied all we need. */

/*-------------------------------------------------------------------------*/

#include "rnet.h"

/*-------------------------------------------------------------------------*/


#include "atp_cmd.h"

/* from /ti/release/ti_5.4.0_p1/code/services/atp/atp_sw_ent.c */

T_ATP_RET atp_reg (
  T_ATP_SW_ENTITY_NAME name,
  T_ATP_CALLBACK return_path,
  T_ATP_ENTITY_MODE mode ,
  T_ATP_SW_ENTITY_ID * sw_id_p
) {
  return RV_OK;
}

T_ATP_RET atp_dereg (T_ATP_SW_ENTITY_ID sw_id)
{
  return RV_OK;
}

/*-------------------------------------------------------------------------*/

/* from /ti/release/ti_5.4.0_p1/code/services/atp/atp_services.c */

T_ATP_RET atp_send_data (
  T_ATP_SW_ENTITY_ID sender_sw_id,
  T_ATP_PORT_NB sender_port_nb,
  void * data_buffer_p,
  UINT32 buffer_size,
  UINT32 * nb_bytes_left_p
) {
  return RV_OK;
}

T_ATP_RET atp_get_data (
  T_ATP_SW_ENTITY_ID receiver_sw_id,
  T_ATP_PORT_NB receiver_port_nb,
  UINT8 * data_buffer,
  UINT32 nb_to_read,
  UINT32 * nb_read_p,
  UINT32 * nb_left_p
) {
  return RV_OK;
}

T_ATP_RET atp_open_port_rsp (
  T_ATP_SW_ENTITY_ID initiator_id,
  T_ATP_PORT_NB initiator_port_nb,
  T_ATP_SW_ENTITY_ID target_id,
  T_ATP_PORT_NB target_port_nb,
  T_ATP_PORT_INFO port_info,
  T_ATP_NO_COPY_INFO no_copy_info,
  T_ATP_CUSTOM_INFO * custom_info_p,
  T_ATP_OPEN_PORT_RESULT result
) {
  return RV_OK;
}

T_ATP_RET atp_free_buffer (void * buffer_p)
{
  return RV_OK;
}