Fork fix: the SDIO wedge is FIXED (esp-hosted-mcu #167)

Root cause (verified against our exact IDF tree, not the community guess):
the "258" in "sdio_write_task: Failed to send data: 258" is NOT a timeout
(that is 263). 258 = 0x102 = ESP_ERR_INVALID_ARG. On the ESP32-P4, block-
mode CMD53 writes require the SOURCE buffer to be 64-byte (cache-line)
aligned; the IDF sdmmc driver rejects a misaligned source with INVALID_ARG
BEFORE any bus activity. esp_hosts write loop then declares "Unrecoverable
host sdio state" and reboots the whole P4. The audio TX payload is not
64-aligned, so streaming mic audio wedged on the very FIRST frame (which is
exactly what we saw: listening -> instant Failed to send -> reboot).

This also explains why buffer/queue/clock/retry tuning all did nothing: the
write never reached the bus. And why our symptom was instant, not after
~100 writes (the community block-mode-desync theory) — it is the first
misaligned buffer, every time.

Fix: vendored esp_hosted 2.12.11 as an editable local component (overrides
the registry copy) and bounce a misaligned TX payload through one aligned
DMA scratch buffer in hosted_sdio_write_block (port_esp_hosted_host_sdio.c).
TX is serialized by the bus lock so a single static bounce buffer is safe;
freed in hosted_sdio_deinit. Host-only change — no C6 reflash.

VERIFIED ON HARDWARE (autonomous self-test): 40s of continuous mic-audio
upstream streaming — the traffic that previously wedged on the first frame
— ran clean, zero timeouts, zero reboots. A guarded SDIO_TX_SELFTEST harness
is kept (compiled out) for future SDIO stress testing.

Credit: root cause + patch designed via multi-agent investigation; the
precise 258=INVALID_ARG decode (correcting the upstream community timeout
assumption) came from checking our actual esp_err.h.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

firmware/components/esp_hosted/slave/main/interface.h

@@ -0,0 +1,138 @@
+/*
+ * SPDX-FileCopyrightText: 2015-2025 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __TRANSPORT_LAYER_INTERFACE_H
+#define __TRANSPORT_LAYER_INTERFACE_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "esp_err.h"
+#include "esp_hosted_log.h"
+#include "esp_hosted_transport.h"
+
+#ifdef CONFIG_ESP_SDIO_HOST_INTERFACE
+
+#if CONFIG_SOC_SDIO_SLAVE_SUPPORTED
+	#include "driver/sdio_slave.h"
+#else
+	#error "SDIO is not supported for this chipset"
+#endif
+
+#endif
+
+#ifdef CONFIG_ESP_SPI_HD_HOST_INTERFACE
+	#include "driver/spi_slave_hd.h"
+#endif
+
+typedef enum {
+	LENGTH_1_BYTE  = 1,
+	LENGTH_2_BYTE  = 2,
+	LENGTH_3_BYTE  = 3,
+	LENGTH_4_BYTE  = 4,
+} byte_length;
+
+typedef void *wlan_buf_handle_t;
+
+typedef enum {
+	SDIO   = 0,
+	SPI    = 1,
+	SPI_HD = 2,
+	UART   = 3,
+} transport_layer;
+
+typedef enum {
+	DEINIT,
+	DEACTIVE,
+	ACTIVE,
+} INTERFACE_STATE;
+
+typedef struct {
+	union {
+#ifdef CONFIG_ESP_SDIO_HOST_INTERFACE
+		sdio_slave_buf_handle_t sdio_buf_handle;
+#endif
+#ifdef CONFIG_ESP_SPI_HD_HOST_INTERFACE
+		spi_slave_hd_data_t * spi_hd_trans_handle;
+#endif
+		wlan_buf_handle_t	wlan_buf_handle;
+		void *priv_buffer_handle;
+	};
+	uint8_t if_type;
+	uint8_t if_num;
+	uint8_t *payload;
+	uint8_t flag;
+	uint16_t payload_len;
+	uint16_t seq_num;
+#if CONFIG_ESP_SPI_HD_HOST_INTERFACE || CONFIG_ESP_UART_HOST_INTERFACE || CONFIG_ESP_SPI_HOST_INTERFACE
+	uint8_t wifi_flow_ctrl_en;
+#endif
+
+	void (*free_buf_handle)(void *buf_handle);
+} interface_buffer_handle_t;
+
+typedef struct {
+	/*
+	union {
+	} phy_context;
+	*/
+	INTERFACE_STATE state;
+}interface_handle_t;
+
+#if CONFIG_ESP_SPI_HOST_INTERFACE
+#define MAX_TRANSPORT_BUF_SIZE ESP_TRANSPORT_SPI_MAX_BUF_SIZE
+#elif CONFIG_ESP_SDIO_HOST_INTERFACE
+#define MAX_TRANSPORT_BUF_SIZE ESP_TRANSPORT_SDIO_MAX_BUF_SIZE
+#elif CONFIG_ESP_SPI_HD_HOST_INTERFACE
+#define MAX_TRANSPORT_BUF_SIZE ESP_TRANSPORT_SPI_HD_MAX_BUF_SIZE
+#elif CONFIG_ESP_UART_HOST_INTERFACE
+#define MAX_TRANSPORT_BUF_SIZE ESP_TRANSPORT_UART_MAX_BUF_SIZE
+#endif
+
+#define BSSID_BYTES_SIZE       6
+
+typedef struct {
+	interface_handle_t * (*init)(void);
+	int32_t (*write)(interface_handle_t *handle, interface_buffer_handle_t *buf_handle);
+	int (*read)(interface_handle_t *handle, interface_buffer_handle_t *buf_handle);
+	esp_err_t (*reset)(interface_handle_t *handle);
+	void (*deinit)(interface_handle_t *handle);
+} if_ops_t;
+
+typedef struct {
+	transport_layer type;
+	void *priv;
+	if_ops_t *if_ops;
+	int (*event_handler)(uint8_t bitmap);
+} interface_context_t;
+
+typedef struct {
+	uint8_t throttle_high_threshold;
+	uint8_t throttle_low_threshold;
+} slave_config_t;
+
+typedef struct {
+	uint8_t current_throttling;
+} slave_state_t;
+
+interface_context_t * interface_insert_driver(int (*callback)(uint8_t val));
+int interface_remove_driver(void);
+void generate_startup_event(uint8_t cap, uint32_t ext_cap);
+int send_to_host_queue(interface_buffer_handle_t *buf_handle, uint8_t queue_type);
+void send_dhcp_dns_info_to_host(uint8_t network_up, uint8_t send_wifi_connected);
+
+#ifndef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+extern slave_config_t slv_cfg_g;
+extern slave_state_t  slv_state_g;
+
+#ifdef __cplusplus
+}
+#endif
+#endif