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jfischer-nokartben
jfischer-no
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kartben
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dap: add DAP backend USB
The backend uses a new USB device stack and bulk endpoints. Only a single instance of the backend function is currently supported. Both DAP packet processing and the new backend are prepared to support multiple instances, but require a user interface and minor modifications. New backen has similar functionality to what is provided by the function in the sample samples/subsys/dap. Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>
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‎subsys/dap/CMakeLists.txt

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@@ -5,3 +5,5 @@ zephyr_include_directories(${CMAKE_CURRENT_SOURCE_DIR})
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zephyr_library()
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zephyr_library_sources(cmsis_dap.c)
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zephyr_library_sources_ifdef(CONFIG_DAP_BACKEND_USB dap_backend_usb.c)

‎subsys/dap/Kconfig

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@@ -41,6 +41,12 @@ config CMSIS_DAP_DEVICE_NAME
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string "Target device name"
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default ""
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config DAP_BACKEND_USB
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bool "USB backend"
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depends on USB_DEVICE_STACK_NEXT
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help
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DAP USB backend using bulk endpoints.
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module = DAP
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module-str = dap
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source "subsys/logging/Kconfig.template.log_config"

‎subsys/dap/dap_backend_usb.c

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@@ -0,0 +1,305 @@
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/*
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* Copyright (c) 2024 Nordic Semiconductor ASA
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#include <zephyr/usb/usbd.h>
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#include <zephyr/drivers/usb/udc.h>
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#include <zephyr/sys/byteorder.h>
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#include "cmsis_dap.h"
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#include <zephyr/logging/log.h>
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LOG_MODULE_REGISTER(dap_usb, CONFIG_DAP_LOG_LEVEL);
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/*
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* This file implements CMSIS DAP USB backend function using bulk endpoints.
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*/
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static uint8_t response_buf[512];
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NET_BUF_POOL_FIXED_DEFINE(dap_func_pool,
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1, 0, sizeof(struct udc_buf_info), NULL);
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UDC_STATIC_BUF_DEFINE(dap_func_buf, 512);
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struct dap_func_desc {
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struct usb_if_descriptor if0;
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struct usb_ep_descriptor if0_out_ep;
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struct usb_ep_descriptor if0_in_ep;
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struct usb_ep_descriptor if0_hs_out_ep;
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struct usb_ep_descriptor if0_hs_in_ep;
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struct usb_desc_header nil_desc;
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};
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#define SAMPLE_FUNCTION_ENABLED 0
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struct dap_func_data {
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struct dap_func_desc *const desc;
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const struct usb_desc_header **const fs_desc;
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const struct usb_desc_header **const hs_desc;
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struct usbd_desc_node *const iface_str_desc_nd;
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atomic_t state;
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};
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static uint8_t dap_func_get_bulk_out(struct usbd_class_data *const c_data)
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{
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struct dap_func_data *data = usbd_class_get_private(c_data);
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct dap_func_desc *desc = data->desc;
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if (usbd_bus_speed(uds_ctx) == USBD_SPEED_HS) {
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return desc->if0_hs_out_ep.bEndpointAddress;
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}
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return desc->if0_out_ep.bEndpointAddress;
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}
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static uint8_t dap_func_get_bulk_in(struct usbd_class_data *const c_data)
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{
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struct dap_func_data *data = usbd_class_get_private(c_data);
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct dap_func_desc *desc = data->desc;
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if (usbd_bus_speed(uds_ctx) == USBD_SPEED_HS) {
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return desc->if0_hs_in_ep.bEndpointAddress;
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}
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return desc->if0_in_ep.bEndpointAddress;
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}
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static int dap_func_request_handler(struct usbd_class_data *c_data,
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struct net_buf *buf, int err)
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{
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct dap_func_data *data = usbd_class_get_private(c_data);
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struct udc_buf_info *bi = NULL;
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bi = (struct udc_buf_info *)net_buf_user_data(buf);
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LOG_DBG("Transfer finished %p -> ep 0x%02x, len %u, err %d",
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(void *)c_data, bi->ep, buf->len, err);
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if (atomic_test_bit(&data->state, SAMPLE_FUNCTION_ENABLED) && err == 0) {
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uint8_t ep = bi->ep;
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size_t len;
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memset(bi, 0, sizeof(struct udc_buf_info));
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if (ep == dap_func_get_bulk_in(c_data)) {
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bi->ep = dap_func_get_bulk_out(c_data);
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net_buf_reset(buf);
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} else {
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bi->ep = dap_func_get_bulk_in(c_data);
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len = dap_execute_cmd(buf->data, response_buf);
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net_buf_reset(buf);
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LOG_DBG("response length %u, starting with [0x%02X, 0x%02X]",
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len, response_buf[0], response_buf[1]);
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net_buf_add_mem(buf, response_buf, MIN(len, net_buf_tailroom(buf)));
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}
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if (usbd_ep_enqueue(c_data, buf)) {
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LOG_ERR("Failed to enqueue buffer");
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usbd_ep_buf_free(uds_ctx, buf);
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}
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} else {
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LOG_ERR("Function is disabled or transfer failed");
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usbd_ep_buf_free(uds_ctx, buf);
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}
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return 0;
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}
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static void *dap_func_get_desc(struct usbd_class_data *const c_data,
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const enum usbd_speed speed)
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{
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struct dap_func_data *data = usbd_class_get_private(c_data);
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if (speed == USBD_SPEED_HS) {
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return data->hs_desc;
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}
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return data->fs_desc;
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}
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struct net_buf *dap_func_buf_alloc(struct usbd_class_data *const c_data,
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const uint8_t ep)
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{
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct net_buf *buf = NULL;
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struct udc_buf_info *bi;
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size_t size;
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if (usbd_bus_speed(uds_ctx) == USBD_SPEED_HS) {
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size = 512U;
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} else {
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size = 64U;
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}
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buf = net_buf_alloc_with_data(&dap_func_pool, dap_func_buf, size, K_NO_WAIT);
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net_buf_reset(buf);
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if (!buf) {
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return NULL;
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}
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bi = udc_get_buf_info(buf);
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memset(bi, 0, sizeof(struct udc_buf_info));
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bi->ep = ep;
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return buf;
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}
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static void dap_func_enable(struct usbd_class_data *const c_data)
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{
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struct dap_func_data *data = usbd_class_get_private(c_data);
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct net_buf *buf;
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LOG_INF("Configuration enabled");
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if (!atomic_test_and_set_bit(&data->state, SAMPLE_FUNCTION_ENABLED)) {
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if (usbd_bus_speed(uds_ctx) == USBD_SPEED_HS) {
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dap_update_pkt_size(512);
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} else {
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dap_update_pkt_size(64);
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}
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buf = dap_func_buf_alloc(c_data, dap_func_get_bulk_out(c_data));
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if (buf == NULL) {
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LOG_ERR("Failed to allocate buffer");
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return;
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}
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if (usbd_ep_enqueue(c_data, buf)) {
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LOG_ERR("Failed to enqueue buffer");
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usbd_ep_buf_free(uds_ctx, buf);
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}
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}
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}
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static void dap_func_disable(struct usbd_class_data *const c_data)
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{
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struct dap_func_data *data = usbd_class_get_private(c_data);
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atomic_clear_bit(&data->state, SAMPLE_FUNCTION_ENABLED);
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LOG_INF("Configuration disabled");
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}
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static int dap_func_init(struct usbd_class_data *c_data)
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{
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struct usbd_context *uds_ctx = usbd_class_get_ctx(c_data);
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struct dap_func_data *data = usbd_class_get_private(c_data);
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struct dap_func_desc *desc = data->desc;
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LOG_DBG("Init class instance %p", (void *)c_data);
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if (usbd_add_descriptor(uds_ctx, data->iface_str_desc_nd)) {
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LOG_ERR("Failed to add interface string descriptor");
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} else {
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desc->if0.iInterface = usbd_str_desc_get_idx(data->iface_str_desc_nd);
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}
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return 0;
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}
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struct usbd_class_api dap_func_api = {
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.request = dap_func_request_handler,
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.get_desc = dap_func_get_desc,
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.enable = dap_func_enable,
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.disable = dap_func_disable,
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.init = dap_func_init,
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};
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#define DAP_FUNC_DESCRIPTOR_DEFINE(n, _) \
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static struct dap_func_desc dap_func_desc_##n = { \
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/* Interface descriptor 0 */ \
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.if0 = { \
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.bLength = sizeof(struct usb_if_descriptor), \
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.bDescriptorType = USB_DESC_INTERFACE, \
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.bInterfaceNumber = 0, \
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.bAlternateSetting = 0, \
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.bNumEndpoints = 2, \
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.bInterfaceClass = USB_BCC_VENDOR, \
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.bInterfaceSubClass = 0, \
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.bInterfaceProtocol = 0, \
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.iInterface = 0, \
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}, \
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\
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/* Endpoint OUT */ \
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.if0_out_ep = { \
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.bLength = sizeof(struct usb_ep_descriptor), \
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.bDescriptorType = USB_DESC_ENDPOINT, \
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.bEndpointAddress = 0x01, \
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.bmAttributes = USB_EP_TYPE_BULK, \
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.wMaxPacketSize = sys_cpu_to_le16(64U), \
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.bInterval = 0x00, \
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}, \
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\
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/* Endpoint IN */ \
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.if0_in_ep = { \
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.bLength = sizeof(struct usb_ep_descriptor), \
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.bDescriptorType = USB_DESC_ENDPOINT, \
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.bEndpointAddress = 0x81, \
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.bmAttributes = USB_EP_TYPE_BULK, \
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.wMaxPacketSize = sys_cpu_to_le16(64U), \
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.bInterval = 0x00, \
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}, \
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\
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/* High-speed Endpoint OUT */ \
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.if0_hs_out_ep = { \
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.bLength = sizeof(struct usb_ep_descriptor), \
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.bDescriptorType = USB_DESC_ENDPOINT, \
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.bEndpointAddress = 0x01, \
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.bmAttributes = USB_EP_TYPE_BULK, \
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.wMaxPacketSize = sys_cpu_to_le16(512), \
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.bInterval = 0x00, \
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}, \
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\
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/* High-speed Endpoint IN */ \
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.if0_hs_in_ep = { \
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.bLength = sizeof(struct usb_ep_descriptor), \
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.bDescriptorType = USB_DESC_ENDPOINT, \
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.bEndpointAddress = 0x81, \
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.bmAttributes = USB_EP_TYPE_BULK, \
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.wMaxPacketSize = sys_cpu_to_le16(512), \
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.bInterval = 0x00, \
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}, \
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\
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/* Termination descriptor */ \
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.nil_desc = { \
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.bLength = 0, \
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.bDescriptorType = 0, \
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}, \
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}; \
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\
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const static struct usb_desc_header *dap_func_fs_desc_##n[] = { \
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(struct usb_desc_header *) &dap_func_desc_##n.if0, \
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(struct usb_desc_header *) &dap_func_desc_##n.if0_out_ep, \
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(struct usb_desc_header *) &dap_func_desc_##n.if0_in_ep, \
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(struct usb_desc_header *) &dap_func_desc_##n.nil_desc, \
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}; \
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\
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const static struct usb_desc_header *dap_func_hs_desc_##n[] = { \
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(struct usb_desc_header *) &dap_func_desc_##n.if0, \
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(struct usb_desc_header *) &dap_func_desc_##n.if0_hs_out_ep, \
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(struct usb_desc_header *) &dap_func_desc_##n.if0_hs_in_ep, \
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(struct usb_desc_header *) &dap_func_desc_##n.nil_desc, \
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};
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#define DAP_FUNC_FUNCTION_DATA_DEFINE(n, _) \
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USBD_DESC_STRING_DEFINE(iface_str_desc_nd_##n, \
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"CMSIS-DAP v2", \
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USBD_DUT_STRING_INTERFACE); \
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\
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static struct dap_func_data dap_func_data_##n = { \
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.desc = &dap_func_desc_##n, \
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.fs_desc = dap_func_fs_desc_##n, \
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.hs_desc = dap_func_hs_desc_##n, \
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.iface_str_desc_nd = &iface_str_desc_nd_##n, \
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}; \
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\
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USBD_DEFINE_CLASS(dap_func_##n, &dap_func_api, &dap_func_data_##n, NULL);
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LISTIFY(1, DAP_FUNC_DESCRIPTOR_DEFINE, ())
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LISTIFY(1, DAP_FUNC_FUNCTION_DATA_DEFINE, ())

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