cmodules: Compatible with the new TWAI configuration method.

Signed-off-by: tinyu <tinyu@m5stack.com>

Author: Tinyu-Zhao

m5stack/cmodules/m5can/modcan.c

@@ -16,19 +16,23 @@
 #include "py/mperrno.h"
 #include "py/mphal.h"
 #include "driver/twai.h"
+#include "esp_clk_tree.h"
+#include "esp_private/esp_clk.h"
 
-#define DEBUG 0
+#define DEBUG 1
 #if DEBUG
 #define DEBUG_printf(...) mp_printf(&mp_plat_print, __VA_ARGS__)
 #else
 #define DEBUG_printf(...) (void)0
 #endif
 
 // Default timings; 125Kbps
-#define CAN_DEFAULT_PRESCALER (32)
-#define CAN_DEFAULT_SJW (3)
-#define CAN_DEFAULT_BS1 (15)
-#define CAN_DEFAULT_BS2 (4)
+#define CAN_DEFAULT_CLK_SRC TWAI_CLK_SRC_DEFAULT
+#define CAN_DEFAULT_QUANTA_RESOLUTION_HZ (2500000)
+#define CAN_DEFAULT_BRP (0)
+#define CAN_DEFAULT_TSEG1 (15)
+#define CAN_DEFAULT_TSEG2 (4)
+#define CAN_DEFAULT_SJW (3)
 
 #define CAN_MAXIMUM_NBRP (512)
 #define CAN_MAXIMUM_NBS1 (256)
@@ -58,6 +62,172 @@
 #define CAN_STATE_RECOVERING 5
 #define CAN_STATE_RUNNING 6
 
+typedef struct {
+ int xtal; // MHz
+ int bitrate; // kbit
+ twai_timing_config_t config;
+} twai_timing_entry_t;
+
+static const twai_timing_entry_t timing_table[] = {
+ // XTAL = 32 MHz
+ {32,
+ 25,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 400000,
+ .brp = 0,
+ .tseg_1 = 11,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 50,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 1000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 100,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 2000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 125,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 4000000,
+ .brp = 0,
+ .tseg_1 = 23,
+ .tseg_2 = 8,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 250,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 4000000,
+ .brp = 0,
+ .tseg_1 = 11,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 500,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 8000000,
+ .brp = 0,
+ .tseg_1 = 11,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 800,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 16000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {32,
+ 1000,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 16000000,
+ .brp = 0,
+ .tseg_1 = 11,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+
+ // XTAL = 40 MHz
+ {40,
+ 25,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 625000,
+ .brp = 0,
+ .tseg_1 = 16,
+ .tseg_2 = 8,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 50,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 1000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 100,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 2000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 125,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 2500000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 250,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 5000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 500,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 10000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 800,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 20000000,
+ .brp = 0,
+ .tseg_1 = 16,
+ .tseg_2 = 8,
+ .sjw = 3,
+ .triple_sampling = false}},
+ {40,
+ 1000,
+ {.clk_src = CAN_DEFAULT_CLK_SRC,
+ .quanta_resolution_hz = 20000000,
+ .brp = 0,
+ .tseg_1 = 15,
+ .tseg_2 = 4,
+ .sjw = 3,
+ .triple_sampling = false}},
+};
+
+static int find_timing_config(int xtal, int bitrate, twai_timing_config_t *out) {
+ for (size_t i = 0; i < sizeof(timing_table) / sizeof(timing_table[0]); ++i) {
+ if (timing_table[i].bitrate == bitrate && timing_table[i].xtal == xtal) {
+ *out = timing_table[i].config;
+ return 0;
+ }
+ }
+ return -1;
+}
+
 typedef struct _pyb_can_obj_t {
  mp_obj_base_t base;
  mp_uint_t can_id;
@@ -96,36 +266,74 @@ static void pyb_can_print(const mp_print_t *print, mp_obj_t self_in, mp_print_ki
 
 // init(mode, prescaler=100, *, sjw=1, bs1=6, bs2=8)
 static mp_obj_t pyb_can_init_helper(pyb_can_obj_t *self, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
- enum { ARG_mode, ARG_tx, ARG_rx, ARG_prescaler, ARG_sjw, ARG_bs1, ARG_bs2, ARG_triple_sampling };
+ enum {
+ ARG_mode,
+ ARG_tx,
+ ARG_rx,
+ ARG_quanta_resolution_hz,
+ ARG_brp,
+ ARG_tseg_1,
+ ARG_tseg_2,
+ ARG_sjw,
+ ARG_triple_sampling,
+ ARG_baudrate,
+ };
  static const mp_arg_t allowed_args[] = {
  {MP_QSTR_mode, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = CAN_MODE_NORMAL}},
  {MP_QSTR_tx, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 2}},
  {MP_QSTR_rx, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 1}},
- {MP_QSTR_prescaler, MP_ARG_INT, {.u_int = CAN_DEFAULT_PRESCALER}},
+ {MP_QSTR_quanta_resolution_hz, MP_ARG_INT, {.u_int = CAN_DEFAULT_QUANTA_RESOLUTION_HZ}},
+ {MP_QSTR_brp, MP_ARG_INT, {.u_int = CAN_DEFAULT_BRP}},
+ {MP_QSTR_tseg_1, MP_ARG_INT, {.u_int = CAN_DEFAULT_TSEG1}},
+ {MP_QSTR_tseg_2, MP_ARG_INT, {.u_int = CAN_DEFAULT_TSEG2}},
  {MP_QSTR_sjw, MP_ARG_INT, {.u_int = CAN_DEFAULT_SJW}},
- {MP_QSTR_bs1, MP_ARG_INT, {.u_int = CAN_DEFAULT_BS1}},
- {MP_QSTR_bs2, MP_ARG_INT, {.u_int = CAN_DEFAULT_BS2}},
  {MP_QSTR_triple_sampling, MP_ARG_BOOL, {.u_bool = false}},
+ {MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 0}},
  };
 
  // parse args
  mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
  mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
- self->t_config.brp = args[ARG_prescaler].u_int;
- self->t_config.tseg_1 = args[ARG_bs1].u_int;
- self->t_config.tseg_2 = args[ARG_bs2].u_int;
- self->t_config.sjw = args[ARG_sjw].u_int;
- self->t_config.triple_sampling = args[ARG_triple_sampling].u_bool;
-
  self->g_config.tx_io = args[ARG_tx].u_int;
  self->g_config.rx_io = args[ARG_rx].u_int;
  self->g_config.mode = args[ARG_mode].u_int;
 
- DEBUG_printf(&mp_plat_print, "prescaler=%u, sjw=%u, bs1=%u, bs2=%u, triple_sampling=%u\n", self->t_config.brp,
- self->t_config.tseg_1, self->t_config.tseg_2, self->t_config.sjw, self->t_config.triple_sampling);
- DEBUG_printf(&mp_plat_print, "mode=%u, tx=%u, rx=%u\n", self->g_config.mode, self->g_config.tx_io,
- self->g_config.rx_io);
+ if (args[ARG_baudrate].u_int != 0) {
+ int xtal = esp_clk_xtal_freq() / 1000000;
+ DEBUG_printf("XTAL frequency: %d MHz\n", xtal);
+ DEBUG_printf("find_timing_config: xtal=%d MHz, baudrate=%d kbps\n", xtal, args[ARG_baudrate].u_int);
+ if (find_timing_config(xtal, args[ARG_baudrate].u_int, &self->t_config) != 0) {
+ DEBUG_printf("Timing config not found for baudrate %d kbps\n", args[ARG_baudrate].u_int);
+ mp_raise_msg_varg(&mp_type_ValueError,
+ MP_ERROR_TEXT("Unsupported baudrate %d kbps for %d MHz crystal. Supported: 25, 50, 100, "
+ "125, 250, 500, 800, 1000"),
+ args[ARG_baudrate].u_int, xtal);
+ }
+ } else {
+ self->t_config.clk_src = CAN_DEFAULT_CLK_SRC;
+ if (args[ARG_quanta_resolution_hz].u_int == 0 && args[ARG_brp].u_int != 0) {
+ uint32_t xtal_apb_freq_hz;
+
+ esp_clk_tree_src_get_freq_hz(CAN_DEFAULT_CLK_SRC, ESP_CLK_TREE_SRC_FREQ_PRECISION_EXACT, &xtal_apb_freq_hz);
+ DEBUG_printf("XTAL APB frequency: %d MHz\n", xtal_apb_freq_hz / 1000000);
+ args[ARG_quanta_resolution_hz].u_int = xtal_apb_freq_hz / args[ARG_brp].u_int;
+ DEBUG_printf("Using quanta_resolution_hz=%u based on brp=%u\n", args[ARG_quanta_resolution_hz].u_int,
+ args[ARG_brp].u_int);
+ args[ARG_brp].u_int = 0;
+ }
+ self->t_config.quanta_resolution_hz = args[ARG_quanta_resolution_hz].u_int;
+ self->t_config.brp = args[ARG_brp].u_int;
+ self->t_config.tseg_1 = args[ARG_tseg_1].u_int;
+ self->t_config.tseg_2 = args[ARG_tseg_2].u_int;
+ self->t_config.sjw = args[ARG_sjw].u_int;
+ self->t_config.triple_sampling = args[ARG_triple_sampling].u_bool;
+ }
+
+ DEBUG_printf("tx=%u, rx=%u, mode=%u\n", self->g_config.tx_io, self->g_config.rx_io, self->g_config.mode);
+ DEBUG_printf("quanta_resolution_hz=%u brp=%u, tseg_1=%u, tseg_2=%u, sjw=%u, triple_sampling=%u\n",
+ self->t_config.quanta_resolution_hz, self->t_config.brp, self->t_config.tseg_1, self->t_config.tseg_2,
+ self->t_config.sjw, self->t_config.triple_sampling);
 
  check_esp_err(twai_driver_install(&self->g_config, &self->t_config, &self->f_config));
  check_esp_err(twai_start());
@@ -157,9 +365,11 @@ static mp_obj_t pyb_can_make_new(const mp_obj_type_t *type, size_t n_args, size_
  }
 
  {
- self->t_config.brp = CAN_DEFAULT_PRESCALER;
- self->t_config.tseg_1 = CAN_DEFAULT_BS1;
- self->t_config.tseg_2 = CAN_DEFAULT_BS2;
+ self->t_config.clk_src = CAN_DEFAULT_CLK_SRC;
+ self->t_config.quanta_resolution_hz = CAN_DEFAULT_QUANTA_RESOLUTION_HZ;
+ self->t_config.brp = CAN_DEFAULT_BRP;
+ self->t_config.tseg_1 = CAN_DEFAULT_TSEG1;
+ self->t_config.tseg_2 = CAN_DEFAULT_TSEG2;
  self->t_config.sjw = CAN_DEFAULT_SJW;
  self->t_config.triple_sampling = false;
  };
@@ -187,7 +397,7 @@ static mp_obj_t pyb_can_make_new(const mp_obj_type_t *type, size_t n_args, size_
  twai_stop();
  // check_esp_err(twai_driver_uninstall());
  int err = twai_driver_uninstall();
- mp_printf(&mp_plat_print, "twai_driver_uninstall() returned %d\n", err);
+ DEBUG_printf("twai_driver_uninstall() returned %d\n", (int)err);
 
  vTaskDelay(10 / portTICK_PERIOD_MS);
  self->is_enabled = false;
@@ -340,24 +550,24 @@ static mp_obj_t pyb_can_send(size_t n_args, const mp_obj_t *pos_args, mp_map_t *
  tx_msg.rtr = args[ARG_rtr].u_bool;
  tx_msg.extd = args[ARG_extframe].u_bool;
  #if DEBUG
- DEBUG_printf(&mp_plat_print, "Income Data:");
+ DEBUG_printf("Send Data:");
  for (size_t i = 0; i < bufinfo.len; i++) {
- DEBUG_printf(&mp_plat_print, "0x%02X ", ((uint8_t *)bufinfo.buf)[i]);
+ DEBUG_printf("0x%02X ", ((uint8_t *)bufinfo.buf)[i]);
  }
- DEBUG_printf(&mp_plat_print, "\n - extd: %d\n", tx_msg.extd);
- DEBUG_printf(&mp_plat_print, " - rtr: %d\n", tx_msg.rtr);
- DEBUG_printf(&mp_plat_print, " - ss: %d\n", tx_msg.ss);
- DEBUG_printf(&mp_plat_print, " - self: %d\n", tx_msg.self);
- DEBUG_printf(&mp_plat_print, " - dlc_non_comp: %d\n", tx_msg.dlc_non_comp);
- DEBUG_printf(&mp_plat_print, "Complete tx_msg:\n");
- DEBUG_printf(&mp_plat_print, " flags: 0x%08X\n", tx_msg.flags);
- DEBUG_printf(&mp_plat_print, " identifier: 0x%08X\n", tx_msg.identifier);
- DEBUG_printf(&mp_plat_print, " data_length_code: %d\n", tx_msg.data_length_code);
- DEBUG_printf(&mp_plat_print, " data: ");
+ DEBUG_printf("\n - extd: %d\n", tx_msg.extd);
+ DEBUG_printf(" - rtr: %d\n", tx_msg.rtr);
+ DEBUG_printf(" - ss: %d\n", tx_msg.ss);
+ DEBUG_printf(" - self: %d\n", tx_msg.self);
+ DEBUG_printf(" - dlc_non_comp: %d\n", tx_msg.dlc_non_comp);
+ DEBUG_printf("Complete tx_msg:\n");
+ DEBUG_printf(" flags: 0x%08X\n", tx_msg.flags);
+ DEBUG_printf(" identifier: 0x%08X\n", tx_msg.identifier);
+ DEBUG_printf(" data_length_code: %d\n", tx_msg.data_length_code);
+ DEBUG_printf(" data: ");
  for (int i = 0; i < bufinfo.len; i++) {
- DEBUG_printf(&mp_plat_print, "0x%02X ", tx_msg.data[i]);
+ DEBUG_printf("0x%02X ", tx_msg.data[i]);
  }
- DEBUG_printf(&mp_plat_print, "\n\n");
+ DEBUG_printf("\n\n");
  #endif
  check_esp_err(twai_transmit(&tx_msg, args[ARG_timeout].u_int));
  return mp_const_none;
@@ -382,12 +592,12 @@ static mp_obj_t pyb_can_recv(size_t n_args, const mp_obj_t *pos_args, mp_map_t *
  twai_message_t rx_msg;
  esp_err_t ret = twai_receive(&rx_msg, args[ARG_timeout].u_int);
  #if DEBUG
- DEBUG_printf(&mp_plat_print, "Received identifier: 0x%08X\n", rx_msg.identifier);
- DEBUG_printf(&mp_plat_print, "received data: ");
+ DEBUG_printf("Received identifier: 0x%08X\n", rx_msg.identifier);
+ DEBUG_printf("received data: ");
  for (int i = 0; i < rx_msg.data_length_code; i++) {
- DEBUG_printf(&mp_plat_print, "0x%02X ", rx_msg.data[i]);
+ DEBUG_printf("0x%02X ", rx_msg.data[i]);
  }
- DEBUG_printf(&mp_plat_print, "\r\n");
+ DEBUG_printf("\r\n");
  #endif
  if (ret != ESP_OK || rx_msg.data_length_code > 8) {
  return mp_const_none;
@@ -540,8 +750,8 @@ MP_DEFINE_CONST_OBJ_TYPE(pyb_can_type, MP_QSTR_CAN, MP_TYPE_FLAG_NONE, make_new,
 MP_REGISTER_ROOT_POINTER(struct _pyb_can_obj_t *pyb_can_obj_all[1]);
 
 static const mp_rom_map_elem_t m5can_module_globals_table[] = {
- { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_m5can) },
- { MP_ROM_QSTR(MP_QSTR_CAN), MP_ROM_PTR(&pyb_can_type) },
+ {MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_m5can)},
+ {MP_ROM_QSTR(MP_QSTR_CAN), MP_ROM_PTR(&pyb_can_type)},
 };
 
 static MP_DEFINE_CONST_DICT(m5can_module_globals, m5can_module_globals_table);