linux-kernel - RE: [EXT] Re: [PATCH RFC net-next 03/19] net: mvpp2: add CM3 SRAM memory map

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

Message-ID: <CO6PR18MB38733FF528490548137E1ACCB0AC9@CO6PR18MB3873.namprd18.prod.outlook.com>
Date:   Sun, 10 Jan 2021 17:49:47 +0000
From:   Stefan Chulski <stefanc@...vell.com>
To:     Andrew Lunn <andrew@...n.ch>
CC:     "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "thomas.petazzoni@...tlin.com" <thomas.petazzoni@...tlin.com>,
        "davem@...emloft.net" <davem@...emloft.net>,
        Nadav Haklai <nadavh@...vell.com>,
        Yan Markman <ymarkman@...vell.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kuba@...nel.org" <kuba@...nel.org>,
        "linux@...linux.org.uk" <linux@...linux.org.uk>,
        "mw@...ihalf.com" <mw@...ihalf.com>,
        "rmk+kernel@...linux.org.uk" <rmk+kernel@...linux.org.uk>,
        "atenart@...nel.org" <atenart@...nel.org>
Subject: RE: [EXT] Re: [PATCH RFC net-next  03/19] net: mvpp2: add CM3 SRAM
 memory map

> 
> > > Should there be -EPROBE_DEFER handling in here somewhere? The SRAM
> > > is a device, so it might not of been probed yet?
> >
> 
> > No, firmware probed during bootloader boot and we can use SRAM. SRAM
> > memory can be safely used.
> 
> A previous patch added:
> 
> +               CP11X_LABEL(cm3_sram): cm3@...000 {
> +                       compatible = "mmio-sram";
> +                       reg = <0x220000 0x800>;
> +                       #address-cells = <1>;
> +                       #size-cells = <1>;
> +                       ranges = <0 0x220000 0x800>;
> +               };
> +
> 
> So it looks like the SRAM is a device, in the linux driver model. And there is a
> driver for this, driver/misc/sram.c. How do you know this device has been
> probed before the Ethernet driver?
> 
>        Andrew

You right, I would add EPROBE_DEFER if of_gen_pool_get return NULL.

Thanks.