[PATCH] dmaengine: mmp_pdma: fix wrong extended DRCMR base for SpacemiT K3

[Guodong Xu]

Hi Troy,

Thanks for the patch.

On 2026-06-15 10:53, Troy Mitchell wrote:
>K3 PDMA shares the same DRCMR layout as K1, where the extended DRCMR

K1 never touches DMA request numbers higher than 45. It's not K1 who needs
the extended DRCMR. PXAxx needs them.

>base address is 0x1100. Commit 6587b8661a0b ("dmaengine: mmp_pdma: add
>SpacemiT K3 support") incorrectly defined DRCMR_EXT_BASE_K3 as 0x1000,

The SpacemiT K3 datasheet still 'incorrectly' carries the base 0x1000.
Refer to [1], Section 16.1.4.6 DMA Connectivity & Assignments
which still states 0x1000 as the base:

0x1004 Request for SSP0 TxReq 0xD4040000
0x1008 Request for SSP0 RxReq 0xD4040000

I would recommend you double check with the SpacemiT team to make sure.
It's better SpacemiT can fix both the online document and downloadable PDF
as well.

[1]: https://www.spacemit.com/community/document/info?lang=en&nodepath=hardware/key_stone/k3/k3_docs/k3_usermanual/16_peripherals/dma.md

>causing all DRCMR accesses for channels >= 64 to be off by 0x100.
>
>Drop the bogus DRCMR_EXT_BASE_K3 macro and reuse DRCMR_EXT_BASE_DEFAULT
>for the K3 ops.

>
>Fixes: 6587b8661a0b ("dmaengine: mmp_pdma: add SpacemiT K3 support")
>Signed-off-by: Troy Mitchell <troy.mitchell at linux.spacemit.com>
>---
>This is a minimal fix for the wrong DRCMR_EXT_BASE_K3 value introduced
>by commit 6587b8661a0b ("dmaengine: mmp_pdma: add SpacemiT K3 support").
>K3 PDMA shares the same extended DRCMR base (0x1100) as K1, so the K3
>ops now reuses DRCMR_EXT_BASE_DEFAULT.

Before we flip it, could you please confirm your source fo truth:
did you confirm 0x1100 on k3 silicon with a real DMA transaction,
or from the datasheet? It would help if you could share your
test setup.

BR,
Guodong Xu

>Best regards,
>--
>Troy Mitchell <troy.mitchell at linux.spacemit.com>
>
>
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