Re: [PATCH 3/3] USB: host: Introduce flag to enable use of 64-bit dma_mask for ehci-platform

[Andreas Herrmann <andreas.herrmann@caviumnetworks.com>]

On Thu, Nov 13, 2014 at 08:44:17PM -0800, Florian Fainelli wrote:
> 2014-11-13 13:36 GMT-08:00 Andreas Herrmann
> <andreas.herrmann@caviumnetworks.com>:
> > ehci-octeon driver used a 64-bit dma_mask. With removal of ehci-octeon
> > and usage of ehci-platform ehci dma_mask is now limited to 32 bits
> > (coerced in ehci_platform_probe).
> >
> > Provide a flag in ehci platform data to allow use of 64 bits for
> > dma_mask.
> 
> Why not just allow enforcing an arbitrary DMA mask?

I thought about that but as it's currently just 32 or 64 bits
a flag is sufficient. (At the moment I am not aware that
other ehci-platform devices would require something else.)

I'll change the flag to a mask if desired.
Alan, what's your opinion about this?


Andreas

> > Cc: David Daney <david.daney@cavium.com>
> > Cc: Alex Smith <alex.smith@imgtec.com>
> > Cc: Alan Stern <stern@rowland.harvard.edu>
> > Signed-off-by: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
> > ---
> >  arch/mips/cavium-octeon/octeon-platform.c |    4 +---
> >  drivers/usb/host/ehci-platform.c          |    3 ++-
> >  include/linux/usb/ehci_pdriver.h          |    1 +
> >  3 files changed, 4 insertions(+), 4 deletions(-)
> >
> > diff --git a/arch/mips/cavium-octeon/octeon-platform.c b/arch/mips/cavium-octeon/octeon-platform.c
> > index eea60b6..12410a2 100644
> > --- a/arch/mips/cavium-octeon/octeon-platform.c
> > +++ b/arch/mips/cavium-octeon/octeon-platform.c
> > @@ -310,6 +310,7 @@ static struct usb_ehci_pdata octeon_ehci_pdata = {
> >  #ifdef __BIG_ENDIAN
> >         .big_endian_mmio        = 1,
> >  #endif
> > +       .dma_mask_64    = 1,
> >         .power_on       = octeon_ehci_power_on,
> >         .power_off      = octeon_ehci_power_off,
> >  };
> > @@ -331,8 +332,6 @@ static void __init octeon_ehci_hw_start(struct device *dev)
> >         octeon2_usb_clocks_stop();
> >  }
> >
> > -static u64 octeon_ehci_dma_mask = DMA_BIT_MASK(64);
> > -
> >  static int __init octeon_ehci_device_init(void)
> >  {
> >         struct platform_device *pd;
> > @@ -347,7 +346,6 @@ static int __init octeon_ehci_device_init(void)
> >         if (!pd)
> >                 return 0;
> >
> > -       pd->dev.dma_mask = &octeon_ehci_dma_mask;
> >         pd->dev.platform_data = &octeon_ehci_pdata;
> >         octeon_ehci_hw_start(&pd->dev);
> >
> > diff --git a/drivers/usb/host/ehci-platform.c b/drivers/usb/host/ehci-platform.c
> > index 2da18ea..6df808b 100644
> > --- a/drivers/usb/host/ehci-platform.c
> > +++ b/drivers/usb/host/ehci-platform.c
> > @@ -155,7 +155,8 @@ static int ehci_platform_probe(struct platform_device *dev)
> >         if (!pdata)
> >                 pdata = &ehci_platform_defaults;
> >
> > -       err = dma_coerce_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32));
> > +       err = dma_coerce_mask_and_coherent(&dev->dev,
> > +               pdata->dma_mask_64 ? DMA_BIT_MASK(64) : DMA_BIT_MASK(32));
> >         if (err)
> >                 return err;
> >
> > diff --git a/include/linux/usb/ehci_pdriver.h b/include/linux/usb/ehci_pdriver.h
> > index 7eb4dcd..f69529e 100644
> > --- a/include/linux/usb/ehci_pdriver.h
> > +++ b/include/linux/usb/ehci_pdriver.h
> > @@ -45,6 +45,7 @@ struct usb_ehci_pdata {
> >         unsigned        big_endian_desc:1;
> >         unsigned        big_endian_mmio:1;
> >         unsigned        no_io_watchdog:1;
> > +       unsigned        dma_mask_64:1;
> >
> >         /* Turn on all power and clocks */
> >         int (*power_on)(struct platform_device *pdev);
> > --
> > 1.7.9.5
> >
> >
> 
> 
> 
> -- 
> Florian