Add ESP32 Ethernet device driver

This driver was implemented by Dong Heng<dongheng@espressif.com>
and reviewed by Alan Carvalho de Assis

arch/xtensa/src/common/xtensa_etherstub.c

@@ -1,70 +0,0 @@
-/****************************************************************************
- * arch/xtensa/src/common/xtensa_etherstub.c
- *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <gnutt@nuttx.org>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- * 3. Neither the name NuttX nor the names of its contributors may be
- *    used to endorse or promote products derived from this software
- *    without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <nuttx/config.h>
-
-#include "xtensa.h"
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: up_netinitialize (stub)
- *
- * Description:
- *   This is a stub version os up_netinitialize.  Normally, up_netinitialize
- *   is defined in board/xyz_network.c for board-specific Ethernet
- *   implementations, or chip/xyx_ethernet.c for chip-specific Ethernet
- *   implementations.  The stub version here is used in the corner case where
- *   the network is enable yet there is no Ethernet driver to be initialized.
- *   In this case, up_initialize will still try to call up_netinitialize()
- *   when one does not exist.  This corner case would occur if, for example,
- *   only a USB network interface is being used or perhaps if a SLIP is
- *   being used).
- *
- *   Use of this stub is deprecated.  The preferred mechanism is to use
- *   CONFIG_NETDEV_LATEINIT=y to suppress the call to up_netinitialize() in
- *   up_initialize().  Then this stub would not be needed.
- *
- ****************************************************************************/
-
-void up_netinitialize(void)
-{
-}

arch/xtensa/src/esp32/Kconfig

@@ -21,9 +21,9 @@ config ESP32_BT
 config ESP32_EMAC
 	bool "Ethernet MAC"
 	default n
-	depends on EXPERIMENTAL
+	select NET
 	---help---
-		No yet implemented
+		Enable ESP32 ethernet support.
 
 config ESP32_I2C
 	bool
@@ -436,4 +436,39 @@ config ESP32_SPIFLASH_DEBUG
 		will show input arguments and result.
 
 endmenu # ESP32_SPIFLASH
+
+menu "Ethernet configuration"
+	depends on ESP32_EMAC
+
+config ESP32_ETH_NRXDESC
+	int "RX description number"
+	default 9
+	---help---
+		Descriptions of RX should be more than TX's.
+
+config ESP32_ETH_NTXDESC
+	int "TX description number"
+	default 8
+
+config ESP32_ETH_MDCPIN
+	int "MDC Pin"
+	default 23
+	range 0 39
+
+config ESP32_ETH_MDIOPIN
+	int "MDIO Pin"
+	default 18
+	range 0 39
+
+config ESP32_ETH_PHY_RSTPIN
+	int "Reset PHY Pin"
+	default 5
+	range 0 39
+
+config ESP32_ETH_PHY_ADDR
+	int "PHY address"
+	default 1
+
+endmenu # ESP32_EMAC
+
 endif # ARCH_CHIP_ESP32

arch/xtensa/src/esp32/Make.defs

@@ -81,18 +81,6 @@ ifeq ($(CONFIG_FS_HOSTFS),y)
   CMN_CSRCS += xtensa_hostfs.c
 endif
 
-
-# Use of common/xtensa_etherstub.c is deprecated.  The preferred mechanism
-# is to use CONFIG_NETDEV_LATEINIT=y to suppress the call to
-# up_netinitialize() in xtensa_initialize.c.  Then this stub would not be
-# needed.
-
-ifneq ($(CONFIG_LX6_ETHERNET),y)
-ifeq ($(CONFIG_NET),y)
-  CMN_CSRCS += xtensa_etherstub.c
-endif
-endif
-
 # Required ESP32 files (arch/xtensa/src/lx6)
 
 CHIP_CSRCS  = esp32_allocateheap.c esp32_clockconfig.c esp32_cpuint.c
@@ -115,6 +103,10 @@ ifeq ($(CONFIG_ESP32_SPIFLASH),y)
 CHIP_CSRCS += esp32_spiflash.c
 endif
 
+ifeq ($(CONFIG_ESP32_EMAC),y)
+CHIP_CSRCS += esp32_emac.c
+endif
+
 # Configuration-dependent ESP32 files
 
 ifeq ($(CONFIG_SMP),y)

arch/xtensa/src/esp32/esp32_emac.h

@@ -0,0 +1,74 @@
+/****************************************************************************
+ * arch/xtensa/src/esp32/esp32_emac.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#ifndef __ARCH_XTENSA_SRC_ESP32_ESP32_EMAC_H
+#define __ARCH_XTENSA_SRC_ESP32_ESP32_EMAC_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#ifndef __ASSEMBLY__
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: esp32_emac_init
+ *
+ * Description:
+ *   Initialize ESP32 ethernet device driver.
+ *
+ * Input Parameters:
+ *   None
+ *
+ * Returned Value:
+ *   0 is returned on success.  Otherwise, a negated errno value is
+ *   returned indicating the nature of the failure:
+ *
+ *     -ENOMEM is returned if no memory resource.
+ *
+ ****************************************************************************/
+
+int esp32_emac_init(void);
+
+#ifdef __cplusplus
+}
+#endif
+#undef EXTERN
+
+#endif /* __ASSEMBLY__ */
+#endif /* __ARCH_XTENSA_SRC_ESP32_ESP32_EMAC_H */

arch/xtensa/src/esp32/esp32_gpio.h

@@ -65,6 +65,7 @@
 #  define FUNCTION_2        (2 << FUNCTION_SHIFT)
 #  define FUNCTION_3        (3 << FUNCTION_SHIFT)
 #  define FUNCTION_4        (4 << FUNCTION_SHIFT)
+#  define FUNCTION_5        (5 << FUNCTION_SHIFT)
 #  define SPECIAL           (7 << FUNCTION_SHIFT)
 
 #define INPUT_PULLUP        (INPUT | PULLUP)
@@ -76,12 +77,14 @@
 #  define INPUT_FUNCTION_2  (INPUT_FUNCTION | FUNCTION_2)
 #  define INPUT_FUNCTION_3  (INPUT_FUNCTION | FUNCTION_3)
 #  define INPUT_FUNCTION_4  (INPUT_FUNCTION | FUNCTION_4)
+#  define INPUT_FUNCTION_5  (INPUT_FUNCTION | FUNCTION_5)
 #define OUTPUT_FUNCTION     (OUTPUT | FUNCTION)
 #  define OUTPUT_FUNCTION_0 (OUTPUT_FUNCTION | FUNCTION_0)
 #  define OUTPUT_FUNCTION_1 (OUTPUT_FUNCTION | FUNCTION_1)
 #  define OUTPUT_FUNCTION_2 (OUTPUT_FUNCTION | FUNCTION_2)
 #  define OUTPUT_FUNCTION_3 (OUTPUT_FUNCTION | FUNCTION_3)
 #  define OUTPUT_FUNCTION_4 (OUTPUT_FUNCTION | FUNCTION_4)
+#  define OUTPUT_FUNCTION_5 (OUTPUT_FUNCTION | FUNCTION_5)
 
 /* Interrupt type used with esp32_gpioirqenable() */
 

arch/xtensa/src/esp32/hardware/esp32_dport.h

@@ -1181,6 +1181,8 @@
 
 #define DPORT_WIFI_CLK_EN_REG          (DR_REG_DPORT_BASE + 0x0CC)
 
+#define DPORT_EMAC_CLK_EN              (BIT(14))
+
 /* DPORT_WIFI_CLK_EN : R/W ;bitpos:[31:0] ;default: 32'hfffce030 ; */
 
 #define DPORT_WIFI_CLK_EN  0xFFFFFFFF
@@ -1192,6 +1194,8 @@
 
 /* DPORT_WIFI_RST : R/W ;bitpos:[31:0] ;default: 32'h0 ; */
 
+#define DPORT_EMAC_RST_EN              (BIT(7))
+
 #define DPORT_WIFI_RST  0xFFFFFFFF
 #define DPORT_WIFI_RST_M  ((DPORT_WIFI_RST_V)<<(DPORT_WIFI_RST_S))
 #define DPORT_WIFI_RST_V  0xFFFFFFFF

boards/xtensa/esp32/esp32-core/README.txt

@@ -21,6 +21,7 @@ Contents
   o Memory Map
   o Serial Console
   o Buttons and LEDs
+  o Ethernet
   o SMP
   o OpenOCD for the ESP32
   o Executing and Debugging from FLASH and IRAM
@@ -215,6 +216,46 @@ Buttons and LEDs
   There are several on-board LEDs for that indicate the presence of power
   and USB activity.  None of these are available for use by software.
 
+Ethernet
+========
+
+  ESP32 has a 802.11 hardware MAC, so just connects to external PHY chip.
+  Due to ESP32's GPIOs are not enough, so recommanded users to use RMII
+  to connect ESP32 to PHY chip, current driver also only supports RMII option.
+
+  The RMII GPIO pins are fixed, but the SMI and functional GPIO pins are optional.
+  
+  RMII GPIO pins are as following:
+
+      ESP32 GPIO          PHY Chip GPIO
+        IO25       <-->       RXD[0]
+        IO26       <-->       RXD[1]
+        IO27       <-->       CRS_DV
+        IO0        <-->       REF_CLK
+        IO19       <-->       TXD[0]
+        IO21       <-->       TX_EN
+        IO22       <-->       TXD[1]
+
+  SMI GPIO pins (default option) are as following:
+
+      ESP32 GPIO          PHY Chip GPIO
+        IO18       <-->       MDIO
+        IO23       <-->       MDC
+
+  Functional GPIO pins(default option) are as following:
+
+      ESP32 GPIO          PHY Chip GPIO
+        IO5        <-->      Reset_N
+
+Espressif has an offcial Ethernet development board:
+
+  https://docs.espressif.com/projects/esp-idf/en/latest/esp32/hw-reference/esp32/get-started-ethernet-kit.html
+
+This driver has been tested according to this board and ESP32 core
+board + LAN8720 module. If users have some issue about using this driver,
+please refer the upper official document, specially the issue that GPIO0
+causes failing to bring the ESP32 chip up.
+
 SMP
 ===