>Subject: Re: [PATCH v2] fsldma: add support to 36-bit physical address > > >On Nov 11, 2010, at 6:16 AM, Li Yang wrote: > >> Expand the dma_mask of fsldma device to 36-bit, indicating that the >> DMA engine can deal with 36-bit physical address and does not need the >> SWIOTLB to create bounce buffer for it when doing dma_map_*(). >> >> Signed-off-by: Li Yang <le...@freescale.com> >> --- >> Add more detailed commit message >> >> drivers/dma/fsldma.c | 4 +++- >> 1 files changed, 3 insertions(+), 1 deletions(-) >> >> diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index >> cea08be..8c79b37 100644 >> --- a/drivers/dma/fsldma.c >> +++ b/drivers/dma/fsldma.c >> @@ -1,7 +1,7 @@ >> /* >> * Freescale MPC85xx, MPC83xx DMA Engine support >> * >> - * Copyright (C) 2007 Freescale Semiconductor, Inc. All rights reserved. >> + * Copyright (C) 2007-2010 Freescale Semiconductor, Inc. All rights >reserved. >> * >> * Author: >> * Zhang Wei <wei.zh...@freescale.com>, Jul 2007 >> @@ -1338,6 +1338,8 @@ static int __devinit fsldma_of_probe(struct >platform_device *op, >> fdev->common.device_control = fsl_dma_device_control; >> fdev->common.dev = &op->dev; >> >> + dma_set_mask(&(op->dev), DMA_BIT_MASK(36)); >> + > >Is there any reason we shouldn't set DMA_BIT_MASK(64) since the DMA block >programming model allows the address to be 64-bits?
The current code is only verified on chips with 36-bit physical address. I'm not sure if the driver can work without any change on the 64-bit chip, although the register model suggests it can work well with 64-bit. If you can confirm that it's compatible with the block on 64-bit chip, then we can change it to 64 bit dma mask. - Leo _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
