From e7449cf97aaecab716158ca9ec4f9da3dbc4940e Mon Sep 17 00:00:00 2001
From: Peter van der Perk <peter.vanderperk@nxp.com>
Date: Mon, 5 Dec 2022 10:07:28 +0100
Subject: [PATCH] S32K3XX EDMA Set Backdoor for DTCM memory map

---
 arch/arm/src/s32k3xx/s32k3xx_edma.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/arch/arm/src/s32k3xx/s32k3xx_edma.c b/arch/arm/src/s32k3xx/s32k3xx_edma.c
index 02e0067ff5..ba70e4624c 100644
--- a/arch/arm/src/s32k3xx/s32k3xx_edma.c
+++ b/arch/arm/src/s32k3xx/s32k3xx_edma.c
@@ -154,6 +154,12 @@ struct s32k3xx_edma_s
   struct s32k3xx_dmach_s dmach[S32K3XX_EDMA_NCHANNELS];
 };
 
+#ifdef CONFIG_S32K3XX_DTCM_HEAP
+extern uint8_t DTCM_BASE_ADDR[];
+extern uint8_t DTCM_END_ADDR[];
+#define DTCM_BACKDOOR_OFFSET 0x1000000
+#endif
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -614,6 +620,22 @@ static inline void s32k3xx_tcd_configure(struct s32k3xx_edmatcd_s *tcd,
                                   EDMA_TCD_CSR_INTHALF : 0;
   tcd->dlastsga = config->flags & EDMA_CONFIG_LOOPDEST ? -config->iter : 0;
 
+#ifdef CONFIG_S32K3XX_DTCM_HEAP
+  /* Remap address to backdoor address for eDMA */
+
+  if (tcd->saddr >= (uint32_t)DTCM_BASE_ADDR
+      && tcd->saddr < (uint32_t)DTCM_END_ADDR)
+    {
+        tcd->saddr += DTCM_BACKDOOR_OFFSET;
+    }
+
+  if (tcd->daddr >= (uint32_t)DTCM_BASE_ADDR
+      && tcd->daddr < (uint32_t)DTCM_END_ADDR)
+    {
+        tcd->daddr += DTCM_BACKDOOR_OFFSET;
+    }
+#endif
+
   /* And special case flags */
 
 #ifdef CONFIG_S32K3XX_EDMA_ELINK