linux-kernel - Re: [PATCH v2] clk: iproc: Fix PLL output frequency calculation

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Wed, 21 Oct 2015 02:41:54 -0700
From:	Michael Turquette <mturquette@...libre.com>
To:	Ray Jui <rjui@...adcom.com>, "Stephen Boyd" <sboyd@...eaurora.org>
Cc:	linux-clk@...r.kernel.org, linux-kernel@...r.kernel.org,
	bcm-kernel-feedback-list@...adcom.com,
	"Simran Rai" <ssimran@...adcom.com>, "Ray Jui" <rjui@...adcom.com>,
	stable@...r.kernel.org
Subject: Re: [PATCH v2] clk: iproc: Fix PLL output frequency calculation

Quoting Ray Jui (2015-10-19 15:27:19)
> From: Simran Rai <ssimran@...adcom.com>
> 
> This patch affects the clocks that use fractional ndivider in their
> PLL output frequency calculation. Instead of 2^20 divide factor, the
> clock's ndiv integer shift was used. Fixed the bug by replacing ndiv
> integer shift with 2^20 factor.
> 
> Signed-off-by: Simran Rai <ssimran@...adcom.com>
> Signed-off-by: Ray Jui <rjui@...adcom.com>
> Reviewed-by: Scott Branden <sbranden@...adcom.com>
> Fixes: 5fe225c105fd ("clk: iproc: add initial common clock support")

Applied to clk-next.

Regards,
Mike

> ---
>  drivers/clk/bcm/clk-iproc-pll.c | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/clk/bcm/clk-iproc-pll.c b/drivers/clk/bcm/clk-iproc-pll.c
> index 2dda4e8..d679ab8 100644
> --- a/drivers/clk/bcm/clk-iproc-pll.c
> +++ b/drivers/clk/bcm/clk-iproc-pll.c
> @@ -345,8 +345,8 @@ static unsigned long iproc_pll_recalc_rate(struct clk_hw *hw,
>         struct iproc_pll *pll = clk->pll;
>         const struct iproc_pll_ctrl *ctrl = pll->ctrl;
>         u32 val;
> -       u64 ndiv;
> -       unsigned int ndiv_int, ndiv_frac, pdiv;
> +       u64 ndiv, ndiv_int, ndiv_frac;
> +       unsigned int pdiv;
>  
>         if (parent_rate == 0)
>                 return 0;
> @@ -366,22 +366,19 @@ static unsigned long iproc_pll_recalc_rate(struct clk_hw *hw,
>         val = readl(pll->pll_base + ctrl->ndiv_int.offset);
>         ndiv_int = (val >> ctrl->ndiv_int.shift) &
>                 bit_mask(ctrl->ndiv_int.width);
> -       ndiv = (u64)ndiv_int << ctrl->ndiv_int.shift;
> +       ndiv = ndiv_int << 20;
>  
>         if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
>                 val = readl(pll->pll_base + ctrl->ndiv_frac.offset);
>                 ndiv_frac = (val >> ctrl->ndiv_frac.shift) &
>                         bit_mask(ctrl->ndiv_frac.width);
> -
> -               if (ndiv_frac != 0)
> -                       ndiv = ((u64)ndiv_int << ctrl->ndiv_int.shift) |
> -                               ndiv_frac;
> +               ndiv += ndiv_frac;
>         }
>  
>         val = readl(pll->pll_base + ctrl->pdiv.offset);
>         pdiv = (val >> ctrl->pdiv.shift) & bit_mask(ctrl->pdiv.width);
>  
> -       clk->rate = (ndiv * parent_rate) >> ctrl->ndiv_int.shift;
> +       clk->rate = (ndiv * parent_rate) >> 20;
>  
>         if (pdiv == 0)
>                 clk->rate *= 2;
> -- 
> 1.9.1
> 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/