esp-idf/components/hal/twai_hal_iram.c
Darian Leung 4c57f50fe4 TWAI: ISR runs when cache is disabled
This commit adds the feature where the TWAI ISR will continue to
run even if the cache is disabled. Whilst cache is disabled, any
received messages will go into the RX queue, and any pending TX
messages in the TX queue will be transmitted. This feature should
be enabled using the CONFIG_TWAI_ISR_IN_IRAM option.
2020-10-10 14:19:32 +08:00

110 lines
5.0 KiB
C

// Copyright 2015-2019 Espressif Systems (Shanghai) PTE LTD
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <stddef.h>
#include "hal/twai_hal.h"
/* ----------------------------- Event Handling ----------------------------- */
uint32_t twai_hal_decode_interrupt_events(twai_hal_context_t *hal_ctx)
{
uint32_t events = 0;
//Read interrupt, status
uint32_t interrupts = twai_ll_get_and_clear_intrs(hal_ctx->dev);
uint32_t status = twai_ll_get_status(hal_ctx->dev);
uint32_t tec = twai_ll_get_tec(hal_ctx->dev);
uint32_t rec = twai_ll_get_rec(hal_ctx->dev);
//Error Warning Interrupt set whenever Error or Bus Status bit changes
if (interrupts & TWAI_LL_INTR_EI) {
if (status & TWAI_LL_STATUS_BS) {
//Currently in BUS OFF state
if (status & TWAI_LL_STATUS_ES) { //EWL is exceeded, thus must have entered BUS OFF
twai_ll_set_mode(hal_ctx->dev, TWAI_MODE_LISTEN_ONLY); //Set to listen only to freeze tec and rec
events |= TWAI_HAL_EVENT_BUS_OFF;
TWAI_HAL_SET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_BUS_OFF);
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_RUNNING);
//Any TX would have been halted by entering bus off. Reset its flag
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_TX_BUFF_OCCUPIED);
} else {
//Below EWL. Therefore TEC is counting down in bus recovery
events |= TWAI_HAL_EVENT_BUS_RECOV_PROGRESS;
}
} else {
//Not in BUS OFF
if (status & TWAI_LL_STATUS_ES) { //Just Exceeded EWL
events |= TWAI_HAL_EVENT_ABOVE_EWL;
TWAI_HAL_SET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_ERR_WARN);
} else if (hal_ctx->state_flags & TWAI_HAL_STATE_FLAG_RECOVERING) {
//Previously undergoing bus recovery. Thus means bus recovery complete
twai_ll_enter_reset_mode(hal_ctx->dev); //Enter reset mode to stop the peripheral
events |= TWAI_HAL_EVENT_BUS_RECOV_CPLT;
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_RECOVERING);
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_BUS_OFF);
} else { //Just went below EWL
events |= TWAI_HAL_EVENT_BELOW_EWL;
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_ERR_WARN);
}
}
}
//Receive Interrupt set whenever RX FIFO is not empty
if (interrupts & TWAI_LL_INTR_RI) {
events |= TWAI_HAL_EVENT_RX_BUFF_FRAME;
}
//Transmit interrupt set whenever TX buffer becomes free
if (interrupts & TWAI_LL_INTR_TI) {
events |= TWAI_HAL_EVENT_TX_BUFF_FREE;
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_TX_BUFF_OCCUPIED);
}
//Error Passive Interrupt on transition from error active to passive or vice versa
if (interrupts & TWAI_LL_INTR_EPI) {
if (tec >= TWAI_ERR_PASS_THRESH || rec >= TWAI_ERR_PASS_THRESH) {
events |= TWAI_HAL_EVENT_ERROR_PASSIVE;
TWAI_HAL_SET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_ERR_PASSIVE);
} else {
events |= TWAI_HAL_EVENT_ERROR_ACTIVE;
TWAI_HAL_RESET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_ERR_PASSIVE);
}
}
//Bus error interrupt triggered on a bus error (e.g. bit, ACK, stuff etc)
if (interrupts & TWAI_LL_INTR_BEI) {
twai_ll_clear_err_code_cap(hal_ctx->dev);
events |= TWAI_HAL_EVENT_BUS_ERR;
}
//Arbitration Lost Interrupt triggered on losing arbitration
if (interrupts & TWAI_LL_INTR_ALI) {
twai_ll_clear_arb_lost_cap(hal_ctx->dev);
events |= TWAI_HAL_EVENT_ARB_LOST;
}
return events;
}
void twai_hal_set_tx_buffer_and_transmit(twai_hal_context_t *hal_ctx, twai_hal_frame_t *tx_frame)
{
//Copy frame into tx buffer
twai_ll_set_tx_buffer(hal_ctx->dev, tx_frame);
//Hit the send command
if (tx_frame->self_reception) {
if (tx_frame->single_shot) {
twai_ll_set_cmd_self_rx_single_shot(hal_ctx->dev);
} else {
twai_ll_set_cmd_self_rx_request(hal_ctx->dev);
}
} else if (tx_frame->single_shot){
twai_ll_set_cmd_tx_single_shot(hal_ctx->dev);
} else {
twai_ll_set_cmd_tx(hal_ctx->dev);
}
TWAI_HAL_SET_FLAG(hal_ctx->state_flags, TWAI_HAL_STATE_FLAG_TX_BUFF_OCCUPIED);
}