[PATCH 03/33] Revert "arm64: dts: ti: k3-j721e-sk: Fix reversed C6x carveout locations"

Beleswar Padhi b-padhi at ti.com
Thu Aug 14 15:38:09 PDT 2025


This reverts commit 9f3814a7c06b7c7296cf8c1622078ad71820454b.

The C6x carveouts are reversed intentionally. This is due to the
requirement to keep the DMA memory region as non-cached, however the
minimum granular cache region for C6x is 16MB. So, C66x_0 marks the
entire C66x_1 16MB memory carveouts as non-cached, and uses the DMA
memory region of C66x_1 as its own, and vice-versa.

This was also called out in the original commit which introduced these
reversed carveouts:
	"The minimum granularity on the Cache settings on C66x DSP cores
	is 16MB, so the DMA memory regions are chosen such that they are
	in separate 16MB regions for each DSP, while reserving a total
	of 16 MB for each DSP and not changing the overall DSP
	remoteproc carveouts."

Fixes: 9f3814a7c06b ("arm64: dts: ti: k3-j721e-sk: Fix reversed C6x carveout locations")
Signed-off-by: Beleswar Padhi <b-padhi at ti.com>
---
 arch/arm64/boot/dts/ti/k3-j721e-sk.dts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/ti/k3-j721e-sk.dts b/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
index ffef3d1cfd55..9882bb1e8097 100644
--- a/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
+++ b/arch/arm64/boot/dts/ti/k3-j721e-sk.dts
@@ -120,7 +120,8 @@ main_r5fss1_core1_memory_region: r5f-memory at a5100000 {
 			no-map;
 		};
 
-		c66_0_dma_memory_region: c66-dma-memory at a6000000 {
+		/* Carveout locations are flipped due to caching */
+		c66_1_dma_memory_region: c66-dma-memory at a6000000 {
 			compatible = "shared-dma-pool";
 			reg = <0x00 0xa6000000 0x00 0x100000>;
 			no-map;
@@ -132,7 +133,8 @@ c66_0_memory_region: c66-memory at a6100000 {
 			no-map;
 		};
 
-		c66_1_dma_memory_region: c66-dma-memory at a7000000 {
+		/* Carveout locations are flipped due to caching */
+		c66_0_dma_memory_region: c66-dma-memory at a7000000 {
 			compatible = "shared-dma-pool";
 			reg = <0x00 0xa7000000 0x00 0x100000>;
 			no-map;
-- 
2.34.1




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