linux-kernel - Re: [PATCH 13/16] clk: renesas: Add CPG core wrapper for RZ/G2L SoC

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]

Message-ID: <CA+V-a8vHQLCL+V0f7bKZOKhtgo9_Rsqy_YjBOa_gCvgZMmBLnA@mail.gmail.com>
Date:   Fri, 28 May 2021 08:51:21 +0100
From:   "Lad, Prabhakar" <prabhakar.csengg@...il.com>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>
Cc:     Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>,
        Rob Herring <robh+dt@...nel.org>,
        Magnus Damm <magnus.damm@...il.com>,
        Michael Turquette <mturquette@...libre.com>,
        Stephen Boyd <sboyd@...nel.org>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will@...nel.org>,
        Jiri Slaby <jirislaby@...nel.org>,
        Philipp Zabel <p.zabel@...gutronix.de>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Linux-Renesas <linux-renesas-soc@...r.kernel.org>,
        linux-clk <linux-clk@...r.kernel.org>,
        "open list:SERIAL DRIVERS" <linux-serial@...r.kernel.org>,
        Linux ARM <linux-arm-kernel@...ts.infradead.org>,
        Biju Das <biju.das.jz@...renesas.com>
Subject: Re: [PATCH 13/16] clk: renesas: Add CPG core wrapper for RZ/G2L SoC

Hi Geert,

On Thu, May 27, 2021 at 1:04 PM Geert Uytterhoeven <geert@...ux-m68k.org> wrote:
>
> Hi Prabhakar,
>
> On Fri, May 14, 2021 at 9:24 PM Lad Prabhakar
> <prabhakar.mahadev-lad.rj@...renesas.com> wrote:
> > Add CPG core wrapper for RZ/G2L family.
> >
> > Based on a patch in the BSP by Binh Nguyen
> > <binh.nguyen.jz@...esas.com>.
> >
> > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@...renesas.com>
> > Reviewed-by: Biju Das <biju.das.jz@...renesas.com>
>
> > --- /dev/null
> > +++ b/drivers/clk/renesas/renesas-rzg2l-cpg.c
>
> > +static int rzg2l_mod_clock_endisable(struct clk_hw *hw, bool enable)
> > +{
> > +       struct mstp_clock *clock = to_mod_clock(hw);
> > +       struct cpg_mssr_priv *priv = clock->priv;
> > +       unsigned int reg = MSSR_OFF(clock->bit) * 4;
>
> The "* 4" here makes it difficult to review the module clock tables.
>
> E.g.
>
>        DEF_MOD("gic",          R9A07G044_CLK_GIC600,
>                                R9A07G044_CLK_P1,
>                                MSSR(5, BIT(0), (BIT(0) | BIT(1)))),
>
> The "5" means the CLK_ON_GIC600 register is at offset CLK_ON_R(5 * 4)
>  = 0x514.  Removing the "* 4" means you could use
> "MSSR(0x14, BIT(0), (BIT(0) | BIT(1))" instead.
>
> Unless it has unpleasant side effects, I'd even consider putting
> the full CLK_ON offset there, i.e.
> "MSSR(0x514, BIT(0), (BIT(0) | BIT(1))" and change the macros like:
>
>     #define CLK_ON_R(reg)          (reg)
>     #define CLK_MON_R(reg)         (0x680 - 0x500 + (reg))
>
OK will do that.

> > --- /dev/null
> > +++ b/drivers/clk/renesas/renesas-rzg2l-cpg.h
>
> > +#define CLK_ON_R(reg)          (0x500 + reg)
> > +#define CLK_MON_R(reg)         (0x680 + reg)
> > +#define CLK_RST_R(reg)         (0x800 + reg)
> > +#define CLK_MRST_R(reg)                (0x980 + reg)
>
> The last three don't seem to be documented?
>
I have asked Chris to send the document across.

Cheers,
Prabhakar