feat/improve_raw_tx Improve Raw Tx on host by doing zero copy

Improve Raw Tx throughput on host by using mempool and zero copy to
send data

Current Raw Tx numbers before and after change:

- for SDIO at 40 MHz CLK: 60 -> 64 Mbits/s
- for SPI FD at 40 MHz CLK: 24 -> 25 Mbits/s
- for SPI HD, 4 data lines, at 40 MHz CLK: 41 -> 43 Mbits/s

host/utils/stats.c

@@ -24,6 +24,9 @@
 #endif
 #include "esp_log.h"
 
+// use mempool and zero copy for Tx
+#include "mempool.h"
+
 #if ESP_PKT_STATS
 struct pkt_stats_t pkt_stats;
 void *pkt_stats_thread = NULL;
@@ -52,6 +55,13 @@ static void * raw_tp_tx_task_id = 0;
 static uint64_t test_raw_tx_len = 0;
 static uint64_t test_raw_rx_len = 0;
 
+static struct mempool * buf_mp_g = NULL;
+
+void stats_mempool_free(void* ptr)
+{
+	mempool_free(buf_mp_g, ptr);
+}
+
 void test_raw_tp_cleanup(void)
 {
 	int ret = 0;
@@ -102,25 +112,30 @@ static void raw_tp_tx_task(void const* pvParameters)
 	uint32_t i = 0;
 	g_h.funcs->_h_sleep(5);
 
+	buf_mp_g = mempool_create(MAX_TRANSPORT_BUFFER_SIZE);
+#ifdef CONFIG_ESP_CACHE_MALLOC
+	assert(channel->memp);
+#endif
+
 	while (1) {
 
 #if CONFIG_H_LOWER_MEMCOPY
 		raw_tp_tx_buf = (uint8_t*)g_h.funcs->_h_calloc(1, MAX_TRANSPORT_BUFFER_SIZE);
 
 		ptr = (uint32_t*) raw_tp_tx_buf;
 		for (i=0; i<(TEST_RAW_TP__BUF_SIZE/4-1); i++, ptr++)
-            *ptr = 0xBAADF00D;
+			*ptr = 0xBAADF00D;
 
 		ret = esp_hosted_tx(ESP_TEST_IF, 0, raw_tp_tx_buf, TEST_RAW_TP__BUF_SIZE, H_BUFF_ZEROCOPY, H_DEFLT_FREE_FUNC);
 
 #else
-		raw_tp_tx_buf = (uint8_t*)g_h.funcs->_h_calloc(1, TEST_RAW_TP__BUF_SIZE);
+		raw_tp_tx_buf = mempool_alloc(buf_mp_g, MAX_TRANSPORT_BUFFER_SIZE, true);
 
-		ptr = (uint32_t*) raw_tp_tx_buf;
+		ptr = (uint32_t*) (raw_tp_tx_buf + H_ESP_PAYLOAD_HEADER_OFFSET);
 		for (i=0; i<(TEST_RAW_TP__BUF_SIZE/4-1); i++, ptr++)
-            *ptr = 0xBAADF00D;
+			*ptr = 0xBAADF00D;
 
-		ret = esp_hosted_tx(ESP_TEST_IF, 0, raw_tp_tx_buf, TEST_RAW_TP__BUF_SIZE, H_BUFF_NO_ZEROCOPY, H_DEFLT_FREE_FUNC);
+		ret = esp_hosted_tx(ESP_TEST_IF, 0, raw_tp_tx_buf, TEST_RAW_TP__BUF_SIZE, H_BUFF_ZEROCOPY, stats_mempool_free);
 #endif
 		if (ret != STM_OK) {
 			ESP_LOGE(TAG, "Failed to send to queue\n");