[U-Boot] [PATCH v4 1/6] nand: Try to align the default buffers

[Tom Warren]

Simon,

> -----Original Message-----
> From: Simon Glass [mailto:sjg at chromium.org]
> Sent: Sunday, July 29, 2012 11:53 PM
> To: U-Boot Mailing List
> Cc: Tom Warren; Stephen Warren; Scott Wood; Simon Glass
> Subject: [PATCH v4 1/6] nand: Try to align the default buffers
> 
> The NAND layer needs to use cache-aligned buffers by default. Towards this
> goal. align the default buffers and their members according to the minimum
> DMA alignment defined for the architecture.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> Changes in v2:
> - Add new patch to align default buffers in nand_base
> 
>  drivers/mtd/nand/nand_base.c |    3 ++-
>  include/linux/mtd/nand.h     |    7 ++++---
>  2 files changed, 6 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
> index bfd668f..891af1f 100644
> --- a/drivers/mtd/nand/nand_base.c
> +++ b/drivers/mtd/nand/nand_base.c
> @@ -2936,7 +2936,8 @@ int nand_scan_tail(struct mtd_info *mtd)
>  	struct nand_chip *chip = mtd->priv;
> 
>  	if (!(chip->options & NAND_OWN_BUFFERS))
> -		chip->buffers = kmalloc(sizeof(*chip->buffers), GFP_KERNEL);
> +		chip->buffers = memalign(ARCH_DMA_MINALIGN,
> +					 sizeof(*chip->buffers));
>  	if (!chip->buffers)
>  		return -ENOMEM;
> 
> diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h index
> 82704de..dc839e7 100644
> --- a/include/linux/mtd/nand.h
> +++ b/include/linux/mtd/nand.h
> @@ -391,9 +391,10 @@ struct nand_ecc_ctrl {
>   * consecutive order.
>   */
>  struct nand_buffers {
> -	uint8_t	ecccalc[NAND_MAX_OOBSIZE];
> -	uint8_t	ecccode[NAND_MAX_OOBSIZE];
> -	uint8_t databuf[NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE];
> +	uint8_t	ecccalc[ALIGN(NAND_MAX_OOBSIZE, ARCH_DMA_MINALIGN)];
> +	uint8_t	ecccode[ALIGN(NAND_MAX_OOBSIZE, ARCH_DMA_MINALIGN)];
> +	uint8_t databuf[ALIGN(NAND_MAX_PAGESIZE + NAND_MAX_OOBSIZE,
> +			      ARCH_DMA_MINALIGN)];
>  };

This causes build failures in the M28EVK build (./MAKEALL -a arm, with current u-boot-tegra/next & gcc 4.4.1):

In file included from mxs_nand.c:29:
/home/tom/denx/uboot-tegra/include/linux/mtd/nand.h:394: warning: implicit declaration of function 'ALIGN'
/home/tom/denx/uboot-tegra/include/linux/mtd/nand.h:394: error: 'ARCH_DMA_MINALIGN' undeclared here (not in a function)
/home/tom/denx/uboot-tegra/include/linux/mtd/nand.h:394: error: variably modified 'ecccalc' at file scope
/home/tom/denx/uboot-tegra/include/linux/mtd/nand.h:395: error: variably modified 'ecccode' at file scope
/home/tom/denx/uboot-tegra/include/linux/mtd/nand.h:397: error: variably modified 'databuf' at file scope
make[1]: *** [mxs_nand.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [drivers/mtd/nand/libnand.o] Error 2
make: *** Waiting for unfinished jobs....

PTAL. Thanks,

Tom
> 
>  /**
> --
> 1.7.7.3
-- 
nvpublic