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Message-ID: <807aa02ed3d54c2f9b31343e19df91526cc3c14e.camel@microchip.com>
Subject: Re: [PATCH linux-next 1/1] phy: Sparx5 Eth SerDes: Use direct
 register operations
From:   Steen Hegelund <steen.hegelund@microchip.com>
To:     Andrew Lunn <andrew@lunn.ch>
CC:     Kishon Vijay Abraham I <kishon@ti.com>,
        Vinod Koul <vkoul@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Microchip UNG Driver List <UNGLinuxDriver@microchip.com>,
        <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        kernel test robot <lkp@intel.com>
Date:   Tue, 30 Mar 2021 15:59:55 +0200
In-Reply-To: <YGMo4K4b9GIUIGu8@lunn.ch>
References: <20210329081438.558885-1-steen.hegelund@microchip.com>
         <20210329081438.558885-2-steen.hegelund@microchip.com>
         <YGIimz9UnVYWfcXH@lunn.ch>
         <2356027828f1fa424751e91e478ff4bc188e7f6d.camel@microchip.com>
         <YGMo4K4b9GIUIGu8@lunn.ch>
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Hi Andrew,

On Tue, 2021-03-30 at 15:34 +0200, Andrew Lunn wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> > > > +static int sparx5_sd25g28_apply_params(struct sparx5_serdes_macro *macro,
> > > > +                                    struct sparx5_sd25g28_params *params)
> > > >  {
> > > > -     struct sparx5_serdes_regval item[] = {
> > > 
> > > Could you just add const here, and then it is no longer on the stack?
> > > 
> > >    Andrew
> > 
> > No it still counts against the stack even as a const structure.
> 
> I'm surprised. Maybe it needs static as well?
> 
> I'm just thinking you can get a much smaller patch if you don't need
> to modify the table, just add additional qualifiers.
> 
>    Andrew


I get your point, but the problem is that the initialization depends on the input parameters: serdes
index, port index, media type, speed etc, so it cannot be made static, and making it const still
uses the stack.

BR
Steen