[PATCH v3 20/33] Revert "arm64: dts: ti: k3-j721e-sk: Fix reversed C6x carveout locations"

Beleswar Padhi
2025-09-05T06:29:38Z

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@ti.com>
---
v3: Changelog:
1. None

Link to v2:
https://lore.kernel.org/all/20250823160901.2177841-21-b-padhi@ti.com/

v2: Changelog:
1. Re-ordered patch from [PATCH 03/33] to [PATCH v2 20/33].

Link to v1:
https://lore.kernel.org/all/20250814223839.3256046-4-b-padhi@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 62b9c13a91e7..5d60aa9bc42b 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@a5100000 {
no-map;
};

- c66_0_dma_memory_region: c66-dma-memory@a6000000 {
+ /* Carveout locations are flipped due to caching */
+ c66_1_dma_memory_region: c66-dma-memory@a6000000 {
compatible = "shared-dma-pool";
reg = <0x00 0xa6000000 0x00 0x100000>;
no-map;
@@ -132,7 +133,8 @@ c66_0_memory_region: c66-memory@a6100000 {
no-map;
};

- c66_1_dma_memory_region: c66-dma-memory@a7000000 {
+ /* Carveout locations are flipped due to caching */
+ c66_0_dma_memory_region: c66-dma-memory@a7000000 {
compatible = "shared-dma-pool";
reg = <0x00 0xa7000000 0x00 0x100000>;
no-map;
--
2.34.1