Messages in this thread | | | Date | Thu, 12 Jun 2014 01:22:29 -0500 | From | Suravee Suthikulpanit <> | Subject | Re: [PATCH 1/1] ata: Check and set 64-bit DMA mask for platform AHCI driver |
| |
On 06/11/2014 04:41 AM, Bartlomiej Zolnierkiewicz wrote: >>> On Fri, May 23, 2014 at 12:35:10PM -0500,suravee.suthikulpanit@amd.com wrote: >>>> > >>From: Suravee Suthikulpanit<Suravee.Suthikulpanit@amd.com> >>>> > >> >>>> > >>The current platform AHCI drier does not set the dma_mask correctly >>>> > >>for 64-bit DMA capable AHCI controller. This patch checks the AHCI >>>> > >>capability bit and set the dma_mask and coherent_dma_mask accordingly. >>>> > >> >>>> > >>Signed-off-by: Suravee Suthikulpanit<Suravee.Suthikulpanit@amd.com> >>>> > >>--- >>>> > >> drivers/ata/libahci_platform.c | 9 +++++++++ >>>> > >> 1 file changed, 9 insertions(+) >>>> > >> >>>> > >>diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c >>>> > >>index 7cb3a85..85049ef 100644 >>>> > >>--- a/drivers/ata/libahci_platform.c >>>> > >>+++ b/drivers/ata/libahci_platform.c >>>> > >>@@ -368,6 +368,15 @@ int ahci_platform_init_host(struct platform_device *pdev, >>>> > >> ahci_init_controller(host); >>>> > >> ahci_print_info(host, "platform"); >>>> > >> >>>> > >>+ if (hpriv->cap & HOST_CAP_64) { >>>> > >>+ if (!dev->dma_mask) > What configuration is the above dev->dma_mask checking supposed to handle? > Is it really needed? If not the current dma_set_mask_and_coherent() call > can be replaced by dma_coerce_mask_and_coherent() one.
I was just trying to be safe and not always assuming that dev->dma_mask is pointing to the dev->coherent_dma_mask. If you think this is not necessary, I can remove this.
> >>>> > >>+ dev->dma_mask = &dev->coherent_dma_mask; >>>> > >>+ >>>> > >>+ rc = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(64)); >>>> > >>+ if (rc) >>>> > >>+ return rc; > Shouldn't we try to set DMA masks to 32-bit ones on error (like it is done > in ahci_configure_dma_masks()) instead of failing the initialization?
I can also add the additional logic to try for 32-bit.
> >>>> > >>+ } >>>> > >>+ >>>> > >> return ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED, >>>> > >> &ahci_platform_sht); >>>> > >> } >>>> > >>-- >>>> > >>1.9.0 > BTW It seems that after DMA masks handling is fixed in the generic AHCI > platform code the driver specific code in ahci_xgene.c can be removed.
I am including Loc Ho, Tuan Phan, and Suman Tripathi to help verifying if code could be removed. If so, I'll send out the change in V2.
Suravee
> > Best regards, > -- > Bartlomiej Zolnierkiewicz > Samsung R&D Institute Poland > Samsung Electronics >
| |