cpu/esp32: add stdio_usb_serial_jtag

cpu/esp32/Makefile

@@ -25,6 +25,10 @@ ifneq (, $(filter esp_freertos, $(USEMODULE)))
  DIRS += freertos
 endif
 
+ifneq (, $(filter stdio_usb_serial_jtag, $(USEMODULE)))
+ DIRS += stdio_usb_serial_jtag
+endif
+
 ifneq (,$(filter esp_wifi% esp_eth, $(USEMODULE)))
  SRC += esp_ztimer.c
 endif

cpu/esp32/Makefile.dep

@@ -166,6 +166,13 @@ ifneq (,$(filter shell,$(USEMODULE)))
  USEMODULE += ps
 endif
 
+ifneq (,$(filter stdio_usb_serial_jtag, $(USEMODULE)))
+ USEMODULE += tsrb
+endif
+ifneq (,$(filter stdio_usb_serial_jtag_rx, $(USEMODULE)))
+ USEMODULE += isrpipe
+endif
+
 ifneq (,$(filter tinyusb_portable_espressif,$(USEMODULE)))
  USEMODULE += esp_idf_usb
 endif

cpu/esp32/include/irq_arch.h

@@ -50,6 +50,7 @@ extern "C" {
 #define CPU_INUM_SYSTIMER 20 /**< Level interrupt with medium priority 2 */
 #define CPU_INUM_BLE 21 /**< Level interrupt with medium priority 2 */
 #define CPU_INUM_CACHEERR 25 /**< Level interrupt with high priority 4 */
+#define CPU_INUM_SERIAL_JTAG 26 /**< Level interrupt with low priority 1 */
 /** @} */
 
 /**

cpu/esp32/irq_arch.c

@@ -83,6 +83,9 @@ static const struct intr_handle_data_t _irq_data_table[] = {
 #if defined(CPU_FAM_ESP32S2) || defined(CPU_FAM_ESP32S3)
  { ETS_USB_INTR_SOURCE, CPU_INUM_USB, 1 },
 #endif
+#if defined(CPU_INUM_SERIAL_JTAG)
+ { ETS_USB_SERIAL_JTAG_INTR_SOURCE, CPU_INUM_SERIAL_JTAG, 1 },
+#endif
 };
 
 #define IRQ_DATA_TABLE_SIZE ARRAY_SIZE(_irq_data_table)

cpu/esp32/stdio_usb_serial_jtag/Makefile

@@ -0,0 +1 @@
+include $(RIOTBASE)/Makefile.base

cpu/esp32/stdio_usb_serial_jtag/usb_serial_jtag.c

@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2023 Benjamin Valentin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup cpu_esp32_usb_serial_jtag ESP32 USB Serial/JTAG interface
+ * @ingroup cpu_esp32
+ * @{
+ *
+ * @file
+ * @brief stdio via USB Serial JTAG debug interface
+ *
+ * @author Benjamin Valentin <benjamin.valentin@ml-pa.com>
+ */
+
+#include <stdint.h>
+#include <stddef.h>
+#include <errno.h>
+#include <sys/types.h>
+
+#include "isrpipe.h"
+#include "tsrb.h"
+
+#include "irq_arch.h"
+#include "hal/interrupt_controller_types.h"
+#include "hal/interrupt_controller_ll.h"
+#include "hal/usb_serial_jtag_ll.h"
+#include "soc/periph_defs.h"
+#include "rom/ets_sys.h"
+
+static uint8_t _rx_buf_mem[USB_SERIAL_JTAG_PACKET_SZ_BYTES];
+static isrpipe_t stdio_serial_isrpipe = ISRPIPE_INIT(_rx_buf_mem);
+
+static tsrb_t serial_tx_rb;
+static uint8_t serial_tx_rb_buf[USB_SERIAL_JTAG_PACKET_SZ_BYTES];
+
+#define IRQ_MASK (USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY | \
+ (IS_USED(MODULE_STDIO_USB_SERIAL_JTAG_RX) * USB_SERIAL_JTAG_INTR_SERIAL_OUT_RECV_PKT))
+
+ssize_t stdio_write(const void *buffer, size_t len)
+{
+ tsrb_add(&serial_tx_rb, buffer, len);
+ USB_SERIAL_JTAG.int_ena.val = IRQ_MASK;
+
+ return len;
+}
+
+ssize_t stdio_read(void* buffer, size_t count)
+{
+ if (IS_USED(MODULE_STDIO_USB_SERIAL_JTAG_RX)) {
+ return (ssize_t)isrpipe_read(&stdio_serial_isrpipe, buffer, count);
+ }
+
+ return -ENOTSUP;
+}
+
+static void _serial_intr_handler(void *arg)
+{
+ (void)arg;
+
+ irq_isr_enter();
+
+ uint32_t mask = usb_serial_jtag_ll_get_intsts_mask();
+
+ /* read data if available */
+ while (IS_USED(MODULE_STDIO_USB_SERIAL_JTAG_RX) &&
+ usb_serial_jtag_ll_rxfifo_data_available()) {
+ isrpipe_write_one(&stdio_serial_isrpipe, USB_SERIAL_JTAG.ep1.rdwr_byte);
+ }
+
+ /* write data if there is a free stop */
+ if (mask & USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY) {
+
+ while (usb_serial_jtag_ll_txfifo_writable()) {
+ int c = tsrb_get_one(&serial_tx_rb);
+ if (c < 0) {
+ /* no more data to send - disable interrupt */
+ USB_SERIAL_JTAG.int_ena.val = IRQ_MASK & ~USB_SERIAL_JTAG_INTR_SERIAL_IN_EMPTY;
+ break;
+ }
+ USB_SERIAL_JTAG.ep1.rdwr_byte = c;
+ }
+ usb_serial_jtag_ll_txfifo_flush();
+ }
+
+ /* clear all interrupt flags */
+ usb_serial_jtag_ll_clr_intsts_mask(mask);
+
+ irq_isr_exit();
+}
+
+void stdio_init(void)
+{
+ tsrb_init(&serial_tx_rb, serial_tx_rb_buf, sizeof(serial_tx_rb_buf));
+
+ /* enable RX interrupt */
+ if (IS_USED(MODULE_STDIO_USB_SERIAL_JTAG_RX)) {
+ USB_SERIAL_JTAG.int_ena.val = USB_SERIAL_JTAG_INTR_SERIAL_OUT_RECV_PKT;
+ }
+
+ /* clear all interrupt flags */
+ usb_serial_jtag_ll_clr_intsts_mask(USB_SERIAL_JTAG_LL_INTR_MASK);
+
+ /* route all UART interrupt sources to same the CPU interrupt */
+ intr_matrix_set(PRO_CPU_NUM, ETS_USB_SERIAL_JTAG_INTR_SOURCE, CPU_INUM_SERIAL_JTAG);
+
+ /* we have to enable therefore the CPU interrupt here */
+ intr_cntrl_ll_set_int_handler(CPU_INUM_SERIAL_JTAG, _serial_intr_handler, NULL);
+ intr_cntrl_ll_enable_interrupts(BIT(CPU_INUM_SERIAL_JTAG));
+}
+/**@}*/

makefiles/pseudomodules.inc.mk

@@ -479,6 +479,7 @@ PSEUDOMODULES += stdio_telnet
 PSEUDOMODULES += stdio_uart_onlcr
 ## @}
 PSEUDOMODULES += stdio_uart_rx
+PSEUDOMODULES += stdio_usb_serial_jtag_rx
 PSEUDOMODULES += stm32_eth
 PSEUDOMODULES += stm32_eth_auto
 PSEUDOMODULES += stm32_eth_link_up

makefiles/stdio.inc.mk

@@ -10,6 +10,7 @@ STDIO_MODULES = \
  stdio_uart \
  stdio_telnet \
  stdio_tinyusb_cdc_acm \
+ stdio_usb_serial_jtag \
  #
 
 # select stdio_uart if no other stdio module is slected
@@ -52,6 +53,9 @@ ifneq (,$(filter stdin,$(USEMODULE)))
  ifneq (,$(filter stdio_uart,$(USEMODULE)))
  USEMODULE += stdio_uart_rx
  endif
+ ifneq (,$(filter stdio_usb_serial_jtag,$(USEMODULE)))
+ USEMODULE += stdio_usb_serial_jtag_rx
+ endif
 endif
 
 ifneq (,$(filter stdio_uart_rx,$(USEMODULE)))