From 4eb118afd1d18d8a2bdfe4413643dae8b7cf4a2e Mon Sep 17 00:00:00 2001
From: Dave Marples <dave@marples.net>
Date: Wed, 26 Sep 2018 10:59:47 -0600
Subject: [PATCH] arch/arm/src/imxrt/imxrt_enet.c:  Fix a race condition in
 setting up the Ethernet Tx transfer.

---
 arch/arm/src/imxrt/imxrt_enet.c           | 11 +++++++++--
 configs/imxrt1050-evk/src/imxrt_bringup.c |  4 +++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/arch/arm/src/imxrt/imxrt_enet.c b/arch/arm/src/imxrt/imxrt_enet.c
index cac04e12e8..643b954e47 100644
--- a/arch/arm/src/imxrt/imxrt_enet.c
+++ b/arch/arm/src/imxrt/imxrt_enet.c
@@ -461,6 +461,7 @@ static bool imxrt_txringfull(FAR struct imxrt_driver_s *priv)
 static int imxrt_transmit(FAR struct imxrt_driver_s *priv)
 {
   struct enet_desc_s *txdesc;
+  irqstate_t flags;
   uint32_t regval;
   uint8_t *buf;
 
@@ -526,9 +527,9 @@ static int imxrt_transmit(FAR struct imxrt_driver_s *priv)
        DEBUGASSERT(txdesc->data == buf);
     }
 
-  /* Start the TX transfer (if it was not already waiting for buffers) */
+  /* Make the following operations atomic */
 
-  putreg32(ENET_TDAR, IMXRT_ENET_TDAR);
+  flags = spin_lock_irqsave();
 
   /* Enable TX interrupts */
 
@@ -540,6 +541,12 @@ static int imxrt_transmit(FAR struct imxrt_driver_s *priv)
 
   (void)wd_start(priv->txtimeout, IMXRT_TXTIMEOUT, imxrt_txtimeout_expiry, 1,
                  (wdparm_t)priv);
+
+  /* Start the TX transfer (if it was not already waiting for buffers) */
+
+  putreg32(ENET_TDAR, IMXRT_ENET_TDAR);
+
+  spin_unlock_irqrestore(flags);
   return OK;
 }
 
diff --git a/configs/imxrt1050-evk/src/imxrt_bringup.c b/configs/imxrt1050-evk/src/imxrt_bringup.c
index 9872cc0fd7..c4486a976b 100644
--- a/configs/imxrt1050-evk/src/imxrt_bringup.c
+++ b/configs/imxrt1050-evk/src/imxrt_bringup.c
@@ -57,6 +57,7 @@
  * Private Functions
  ****************************************************************************/
 
+#if defined(CONFIG_I2C_DRIVER) && defined(CONFIG_IMXRT_LPI2C1)
 static void imxrt_i2c_register(int bus)
 {
   FAR struct i2c_master_s *i2c;
@@ -77,6 +78,7 @@ static void imxrt_i2c_register(int bus)
         }
     }
 }
+#endif
 
 /****************************************************************************
  * Public Functions
@@ -109,7 +111,7 @@ int imxrt_bringup(void)
     }
 #endif
 
-#if defined ( CONFIG_I2C_DRIVER ) & (CONFIG_IMXRT_LPI2C1)
+#if defined(CONFIG_I2C_DRIVER) && defined(CONFIG_IMXRT_LPI2C1)
   imxrt_i2c_register(1);
 #endif