linux-kernel - Re: [PATCH 1/2] mtd: rawnand: gpmi: Remove explicit default gpmi clock setting for i.MX6

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]

Date:   Wed, 3 Nov 2021 11:13:08 -0500
From:   Han Xu <han.xu@....com>
To:     Christian Eggers <ceggers@...i.de>
Cc:     Michael Trimarchi <michael@...rulasolutions.com>,
        Miquel Raynal <miquel.raynal@...tlin.com>,
        Stefan Riedmueller <S.Riedmueller@...tec.de>,
        Greg Ungerer <gerg@...nel.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Christian Hemp <C.Hemp@...tec.de>,
        Boris Brezillon <bbrezillon@...nel.org>,
        Richard Weinberger <richard@....at>,
        Vignesh Raghavendra <vigneshr@...com>,
        linux-mtd@...ts.infradead.org, linux-kernel@...r.kernel.org,
        stable@...r.kernel.org
Subject: Re: [PATCH 1/2] mtd: rawnand: gpmi: Remove explicit default gpmi
 clock setting for i.MX6

On 21/11/02 09:20PM, Christian Eggers wrote:
> From: Stefan Riedmueller <s.riedmueller@...tec.de>
> 
> There is no need to explicitly set the default gpmi clock rate during
> boot for the i.MX 6 since this is done during nand_detect anyway.
> 
> Signed-off-by: Stefan Riedmueller <s.riedmueller@...tec.de>
> Cc: stable@...r.kernel.org
> ---
> @stable: This patch fixes a bug because this (superfluous) call to
>          clk_set_rate() misses the required clock gating. The resulting
>          clock glitches can prevent the system from booting.
> 
> Changelog:
> -----------
> RFC --> v1
> - Cc: stable@...r.kernel.org
> 
>  drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c | 9 ---------
>  1 file changed, 9 deletions(-)
> 
> diff --git a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> index 4d08e4ab5c1b..a1f7000f033e 100644
> --- a/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> +++ b/drivers/mtd/nand/raw/gpmi-nand/gpmi-nand.c
> @@ -1034,15 +1034,6 @@ static int gpmi_get_clks(struct gpmi_nand_data *this)
>  		r->clock[i] = clk;
>  	}
>  
> -	if (GPMI_IS_MX6(this))
> -		/*
> -		 * Set the default value for the gpmi clock.
> -		 *
> -		 * If you want to use the ONFI nand which is in the
> -		 * Synchronous Mode, you should change the clock as you need.
> -		 */
> -		clk_set_rate(r->clock[0], 22000000);
> -

Acked-by: Han Xu <han.xu@....com>

>  	return 0;
>  
>  err_clock:
> -- 
> Christian Eggers
> Embedded software developer
> 
> Arnold & Richter Cine Technik GmbH & Co. Betriebs KG
> Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRA 57918
> Persoenlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH
> Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRB 54477
> Geschaeftsfuehrer: Dr. Michael Neuhaeuser; Stephan Schenk; Walter Trauninger; Markus Zeiler
>