Re: [PATCH 1/2] net: ethernet: bgmac: init sequence bug

[Sergei Shtylyov]

Hello!

On 2/2/2017 1:39 AM, Jon Mason wrote:

> From: Zac Schroff <zschroff@xxxxxxxxxxxx>
>
> Fix a bug in the 'bgmac' driver init sequence that blind writes for init
> sequence where it should preserve most bits other than the ones it is
> deliberately manipulating.
>
> Signed-off-by: Zac Schroff <zschroff@xxxxxxxxxxxx>
> Signed-off-by: Jon Mason <jon.mason@xxxxxxxxxxxx>
> Fixes: f6a95a24957 ("net: ethernet: bgmac: Add platform device support")
> ---
>  drivers/net/ethernet/broadcom/bgmac-platform.c | 10 +++++++---
>  include/linux/bcma/bcma_regs.h                 |  1 +
>  2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/net/ethernet/broadcom/bgmac-platform.c b/drivers/net/ethernet/broadcom/bgmac-platform.c
> index 6f736c1..9bbe05c 100644
> --- a/drivers/net/ethernet/broadcom/bgmac-platform.c
> +++ b/drivers/net/ethernet/broadcom/bgmac-platform.c
> @@ -61,15 +61,19 @@ static bool platform_bgmac_clk_enabled(struct bgmac *bgmac)
>
>  static void platform_bgmac_clk_enable(struct bgmac *bgmac, u32 flags)
>  {
> -	bgmac_idm_write(bgmac, BCMA_IOCTL,
> -			(BCMA_IOCTL_CLK | BCMA_IOCTL_FGC | flags));
> +	u32 regval;
> +
> +	/* Some bits of BCMA_IOCTL set by HW/ATF & should not change */
> +	regval = bgmac_idm_read(bgmac, BCMA_IOCTL) & BCMA_IOCTL_DO_NOT_MODIFY;
> +	regval |= ((flags & (~BCMA_IOCTL_DO_NOT_MODIFY)) | BCMA_IOCTL_CLK);

   The innermost parens aren't necessary. And the outermost as well.

[...]

MBR, Sergei