Re: [PATCH 01/11] spi/pxa2xx: allow building on a 64-bit kernel

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Tue, Jan 08, 2013 at 11:27:45AM +0800, Eric Miao wrote:
> On Mon, Jan 7, 2013 at 6:44 PM, Mika Westerberg
> <mika.westerberg@linux.intel.com> wrote:
> > In addition fix following warnings seen when compiling 64-bit:
> >
> > drivers/spi/spi-pxa2xx.c: In function ‘map_dma_buffers’: drivers/spi/spi-pxa2xx.c:384:7: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
> > drivers/spi/spi-pxa2xx.c:384:40: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
> > drivers/spi/spi-pxa2xx.c: In function ‘pxa2xx_spi_probe’:
> > drivers/spi/spi-pxa2xx.c:1572:34: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
> > drivers/spi/spi-pxa2xx.c:1572:34: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
> > drivers/spi/spi-pxa2xx.c:1572:34: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
> > drivers/spi/spi-pxa2xx.c:1572:27: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
> >
> > Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> > ---
> >  drivers/spi/Kconfig      |    4 ++--
> >  drivers/spi/spi-pxa2xx.c |    5 ++---
> >  2 files changed, 4 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> > index 2e188e1..a90393d 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -299,7 +299,7 @@ config SPI_PPC4xx
> >
> >  config SPI_PXA2XX
> >         tristate "PXA2xx SSP SPI master"
> > -       depends on (ARCH_PXA || (X86_32 && PCI)) && EXPERIMENTAL
> > +       depends on ARCH_PXA || PCI
> >         select PXA_SSP if ARCH_PXA
> >         help
> >           This enables using a PXA2xx or Sodaville SSP port as a SPI master
> > @@ -307,7 +307,7 @@ config SPI_PXA2XX
> >           additional documentation can be found a Documentation/spi/pxa2xx.
> >
> >  config SPI_PXA2XX_PCI
> > -       def_bool SPI_PXA2XX && X86_32 && PCI
> > +       def_tristate SPI_PXA2XX && PCI
> >
> 
> Generally looks good to me, I think we could split the changes to
> 
> * Kconfig (adding 64-bit support or removing restrictions of X86_32
> for the driver)
> * and to spi-pxa2xx.c (mostly to handle the alignment warnings)

OK.

> 
> >  config SPI_RSPI
> >         tristate "Renesas RSPI controller"
> > diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c
> > index 5c8c4f5..7fac65d 100644
> > --- a/drivers/spi/spi-pxa2xx.c
> > +++ b/drivers/spi/spi-pxa2xx.c
> > @@ -47,7 +47,7 @@ MODULE_ALIAS("platform:pxa2xx-spi");
> >
> >  #define DMA_INT_MASK           (DCSR_ENDINTR | DCSR_STARTINTR | DCSR_BUSERR)
> >  #define RESET_DMA_CHANNEL      (DCSR_NODESC | DMA_INT_MASK)
> > -#define IS_DMA_ALIGNED(x)      ((((u32)(x)) & 0x07) == 0)
> > +#define IS_DMA_ALIGNED(x)      IS_ALIGNED((unsigned long)x, DMA_ALIGNMENT)
> 
> OK.
> 
> >  #define MAX_DMA_LEN            8191
> >  #define DMA_ALIGNMENT          8
> >
> > @@ -1569,8 +1569,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev)
> >         master->transfer = transfer;
> >
> >         drv_data->ssp_type = ssp->type;
> > -       drv_data->null_dma_buf = (u32 *)ALIGN((u32)(drv_data +
> > -                                               sizeof(struct driver_data)), 8);
> > +       drv_data->null_dma_buf = (u32 *)PTR_ALIGN(drv_data + 1, 8);
> 
> Hmm... the original code seems to have big problem and interestingly no
> one has reported the issue, possibly due to null_dma_buf being seldomly
> used.
> 
> However, it's still a bit obscure to have 'drv_data + 1', 'drv_data[1]' might
> be a bit better for readability.
> 
> And it'll be better to have DMA_ALIGNTMENT here instead of a hard-coded
> constant '8'.
>     u

Sure, I'll change that.

Thanks for your comments.