Commit 00ff4d68 authored by Ben Collins's avatar Ben Collins Committed by Vinod Koul
Browse files

fsldma: Set correct dma_mask based on hw capability 



The driver currently hardcodes DMA_BIT_MASK to 36-bits, which is only
correct on eloplus:

elo3		supports 40-bits
eloplus		supports 36-bits
elo		supports 32-bits

This is based on 0x08 cdar register documention in the respective
reference manuals. Set the dma mask accordingly.

Feedback from Arnd Bergmann:

- Use match data to set address bit mask

Signed-off-by: default avatarBen Collins <bcollins@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Vinod Koul <vkoul@kernel.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: dmaengine@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/2025050513-complex-crane-2babb6@boujee-and-buff


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent 17502e7d

drivers/dma/fsldma.c

+16 −4
Original line number Diff line number Diff line
@@ -1226,6 +1226,8 @@ static int fsldma_of_probe(struct platform_device *op) 


	fdev->dev = &op->dev;

	INIT_LIST_HEAD(&fdev->common.channels);

	/* The DMA address bits supported for this device. */

	fdev->addr_bits = (long)device_get_match_data(fdev->dev);



	/* ioremap the registers for use */

	fdev->regs = of_iomap(op->dev.of_node, 0);
@@ -1254,7 +1256,7 @@ static int fsldma_of_probe(struct platform_device *op) 
	fdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);

	fdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_DESCRIPTOR;



	dma_set_mask(&(op->dev), DMA_BIT_MASK(36));

	dma_set_mask(&(op->dev), DMA_BIT_MASK(fdev->addr_bits));



	platform_set_drvdata(op, fdev);
@@ -1387,10 +1389,20 @@ static const struct dev_pm_ops fsldma_pm_ops = { 
};

#endif



/* The .data field is used for dma-bit-mask. */

static const struct of_device_id fsldma_of_ids[] = {

	{ .compatible = "fsl,elo3-dma", },

	{ .compatible = "fsl,eloplus-dma", },

	{ .compatible = "fsl,elo-dma", },

	{

		.compatible = "fsl,elo3-dma",

		.data = (void *)40,

	},

	{

		.compatible = "fsl,eloplus-dma",

		.data = (void *)36,

	},

	{

		.compatible = "fsl,elo-dma",

		.data = (void *)32,

	},

	{}

};

MODULE_DEVICE_TABLE(of, fsldma_of_ids);

drivers/dma/fsldma.h

+1 −0
Original line number Diff line number Diff line
@@ -124,6 +124,7 @@ struct fsldma_device { 
	struct fsldma_chan *chan[FSL_DMA_MAX_CHANS_PER_DEVICE];

	u32 feature;		/* The same as DMA channels */

	int irq;		/* Channel IRQ */

	int addr_bits;		/* DMA addressing bits supported */

};



/* Define macros for fsldma_chan->feature property */