Fixed bug #815.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/stable_16.1.x@10074 35acf78f-673a-0410-8e92-d51de3d6d3f4

os/hal/ports/STM32/LLD/MACv1/mac_lld.c

@@ -472,6 +472,9 @@ void mac_lld_release_transmit_descriptor(MACTransmitDescriptor *tdp) {
                          STM32_TDES0_IC | STM32_TDES0_LS | STM32_TDES0_FS |
                          STM32_TDES0_TCH | STM32_TDES0_OWN;
 
+  /* Wait for the write to tdes0 to go through before resuming the DMA.*/
+  __DSB();
+
   /* If the DMA engine is stalled then a restart request is issued.*/
   if ((ETH->DMASR & ETH_DMASR_TPS) == ETH_DMASR_TPS_Suspended) {
     ETH->DMASR   = ETH_DMASR_TBUS;
@@ -550,6 +553,9 @@ void mac_lld_release_receive_descriptor(MACReceiveDescriptor *rdp) {
   /* Give buffer back to the Ethernet DMA.*/
   rdp->physdesc->rdes0 = STM32_RDES0_OWN;
 
+  /* Wait for the write to rdes0 to go through before resuming the DMA.*/
+  __DSB();
+
   /* If the DMA engine is stalled then a restart request is issued.*/
   if ((ETH->DMASR & ETH_DMASR_RPS) == ETH_DMASR_RPS_Suspended) {
     ETH->DMASR   = ETH_DMASR_RBUS;

readme.txt

@@ -75,6 +75,8 @@
 *** 16.1.8 ***
 - HAL: Fixed STM32 OTGv1 driver not serving interrupts for endpoints > 5
        (bug #816).
+- HAL: Fixed STM32 MAC driver needs __DSB() for STM32F7 when operating in
+       SRAM1/2 (bug #815).
 
 *** 16.1.7 ***
 - VAR: Fixed BYTE_ORDER redefined in lwip_bindings/arch/cc.h (bug #814).