drivers: spi: siwx91x: Use GPDMA rather than UDMA #97534
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Group the DMA nodes in the same place. Signed-off-by: Jérôme Pouiller <[email protected]>
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| desc = gspi_siwx91x_fill_data_desc(cfg, channel->dma_descriptors, buffer, buffer_count, | ||
| padded_transaction_size, is_tx, dfs); | ||
| padded_transaction_size, is_tx, 4); |
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Instead, remove the last parameter (dfs) from this function and change the GSPI_DMA_MAX_DESCRIPTOR_TRANSFER_SIZE to 4096
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| ret = gspi_siwx91x_dma_config(spi_dev, channel, | ||
| ARRAY_INDEX(channel->dma_descriptors, desc) + 1, is_tx, dfs); | ||
| ARRAY_INDEX(channel->dma_descriptors, desc) + 1, is_tx, 1); |
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Hardcoding this to 1 may limit the source_data_size and dest_data_size to 8-bit. Instead pass dfs to the function and hardcode source_burst_length and dest_burst_length to 1 in gspi_siwx91x_dma_config function to enable transfer for 16-bit data size
| pinctrl-names = "default"; | ||
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| dmas = <&dma0 11>, <&dma0 10>; | ||
| dmas = <&dma1 0 11>, <&dma1 1 10>; |
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I think this too should be replaced with gpdma
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Yeah, CI also noticed it.
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GPDMA hardware block has some requirement regarding the buffers alignments. Note the previous condition was too permissive. It ignored source_burst_length during the check of the transaction size. Signed-off-by: Jérôme Pouiller <[email protected]>
The DMAs expect a 32 bits aligned address as source. Signed-off-by: Jérôme Pouiller <[email protected]>
The siwx91x platform provides two DMA block: UDMA and GPDMA. GPDMA require the dma_slot attribute. Signed-off-by: Jérôme Pouiller <[email protected]>
Since various macros don't end with a colon, the code formatters give bad results. Let's fix that. Signed-off-by: Jérôme Pouiller <[email protected]>
Properly reset the device before the transaction, whatever its previous state. Signed-off-by: Jérôme Pouiller <[email protected]>
Silabs siwx91x offer two DMA hardware block: GPDMA and UDMA.
While UDMA has some benefit when running in low power modes, GPDMA offer
better performances. So GDMA is probably better suited for SPI device.
Ideally, we would like to leave the ability to switch back to UDMA.
Unfortunately, UDMA and GPDMA are not configured in the same way:
- the maximum length of the block are different (1024 or 2048 for UDMA
and 4096 for GPDMA)
- the burst length is different
So, we only support GPDMA.
Signed-off-by: Jérôme Pouiller <[email protected]>
We now support GPDMA with SPI. So update the tests to reflect this changes. Signed-off-by: Jérôme Pouiller <[email protected]>
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zephyrbot
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area: Tests
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Martinhoff-maker,
asmellby,
decsny,
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nashif,
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teburd
jhedberg
approved these changes
Oct 15, 2025
Martinhoff-maker
approved these changes
Oct 15, 2025
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Silabs siwx91x offer two DMA hardware block: GPDMA and UDMA.
While UDMA has some benefit when running in low power modes, GPDMA offer better performances. So GDMA is probably better suited for SPI device.
Ideally, we would like to leave the ability to switch back to UDMA.
Unfortunately, UDMA and GPDMA are not configured in the same way:
So, we only support GPDMA.