fix(cdc_acm): Fix Receive buffer append function on ESP32-P4

The Receive buffer append function changes location of the data buffer.
While this works fine on S2 and S3, it will crash on P4 because now we must do
cache sync for the data buffer. This will crash on unaligned cache sync,
so this feature is disabled on P4 for now.

host/class/cdc/usb_host_cdc_acm/CHANGELOG.md

@@ -1,7 +1,8 @@
-## [Unreleased]
+## 2.0.5
 
 - Fixed CDC descriptor parsing logic, when some CDC devices could not be opened
 - Added an option to open a CDC device with any VID/PID
+- Fixed crash on ESP32-P4 if Receive buffer append function (introduced in v2.0.0) was used; this function does not work on P4 yet
 
 ## 2.0.4
 

host/class/cdc/usb_host_cdc_acm/cdc_acm_host.c

@@ -12,6 +12,7 @@
 #include "freertos/task.h"
 #include "freertos/semphr.h"
 #include "freertos/event_groups.h"
+#include "soc/soc_caps.h"
 #include "esp_log.h"
 #include "esp_check.h"
 #include "esp_system.h"
@@ -172,7 +173,8 @@ static void cdc_acm_reset_in_transfer(cdc_dev_t *cdc_dev)
     uint8_t **ptr = (uint8_t **)(&(transfer->data_buffer));
     *ptr = cdc_dev->data.in_data_buffer_base;
     transfer->num_bytes = transfer->data_buffer_size;
-    // This is a hotfix for IDF changes, where 'transfer->data_buffer_size' does not contain actual buffer length, but *allocated* buffer length, which can be larger
+    // This is a hotfix for IDF changes, where 'transfer->data_buffer_size' does not contain actual buffer length,
+    // but *allocated* buffer length, which can be larger if CONFIG_HEAP_POISONING_COMPREHENSIVE is enabled
     transfer->num_bytes -= transfer->data_buffer_size % cdc_dev->data.in_mps;
 }
 
@@ -805,6 +807,7 @@ static void in_xfer_cb(usb_transfer_t *transfer)
         // In this case, the next received data must be appended to the existing buffer.
         // Since the data_buffer in usb_transfer_t is a constant pointer, we must cast away to const qualifier.
         if (!data_processed) {
+#if !SOC_CACHE_INTERNAL_MEM_VIA_L1CACHE
             // In case the received data was not processed, the next RX data must be appended to current buffer
             uint8_t **ptr = (uint8_t **)(&(transfer->data_buffer));
             *ptr += transfer->actual_num_bytes;
@@ -829,6 +832,11 @@ static void in_xfer_cb(usb_transfer_t *transfer)
                 cdc_acm_reset_in_transfer(cdc_dev);
                 cdc_dev->serial_state.bOverRun = false;
             }
+#else
+            // For targets that must sync internal memory through L1CACHE, we cannot change the data_buffer
+            // because it would lead to unaligned cache sync, which is not allowed
+            ESP_LOGW(TAG, "RX buffer append is not yet supported on ESP32-P4!");
+#endif
         } else {
             cdc_acm_reset_in_transfer(cdc_dev);
         }

host/class/cdc/usb_host_cdc_acm/idf_component.yml

@@ -1,5 +1,5 @@
 ## IDF Component Manager Manifest File
-version: "2.0.4"
+version: "2.0.5"
 description: USB Host CDC-ACM driver
 tags:
   - usb