linux-kernel - Re: [PATCH 11/11] dt: Exynos: add Snow SPI NOR node.

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

Date:	Thu, 04 Jun 2015 11:04:18 +0900
From:	Krzysztof Kozlowski <k.kozlowski@...sung.com>
To:	Michal Suchanek <hramrach@...il.com>,
	Rob Herring <robh+dt@...nel.org>,
	Pawel Moll <pawel.moll@....com>,
	Mark Rutland <mark.rutland@....com>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Kumar Gala <galak@...eaurora.org>,
	Russell King <linux@....linux.org.uk>,
	Kukjin Kim <kgene@...nel.org>,
	Vinod Koul <vinod.koul@...el.com>,
	Dan Williams <dan.j.williams@...el.com>,
	David Woodhouse <dwmw2@...radead.org>,
	Brian Norris <computersforpeace@...il.com>,
	Han Xu <han.xu@...escale.com>, Mark Brown <broonie@...nel.org>,
	Geert Uytterhoeven <geert+renesas@...der.be>,
	Marek Vasut <marex@...x.de>,
	Rafał Miłecki <zajec5@...il.com>,
	Alison Chaiken <alison_chaiken@...tor.com>,
	Huang Shijie <b32955@...escale.com>,
	Ben Hutchings <ben@...adent.org.uk>,
	Knut Wohlrab <knut.wohlrab@...bosch.com>,
	"Bean Huo 霍斌斌 (beanhuo)" 
	<beanhuo@...ron.com>, "grmoore@...era.com" <grmoore@...era.com>,
	devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-samsung-soc@...r.kernel.org, dmaengine@...r.kernel.org,
	linux-mtd@...ts.infradead.org, linux-spi@...r.kernel.org
Subject: Re: [PATCH 11/11] dt: Exynos: add Snow SPI NOR node.

On 04.06.2015 06:26, Michal Suchanek wrote:
> The Snow has onboard SPI NOR flash which contains the bootloader.
> 
> Add DT node for this flash chip. The flash is rated 133MHz but the pl330
> controller can transfer only up to 128 bytes at this speed so use more
> conservative settings. Even at 40MHz pl330 can transfer at most 64k with
> the current driver.
> 
> Signed-off-by: Michal Suchanek <hramrach@...il.com>
> ---
>  arch/arm/boot/dts/exynos5250-snow.dts | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/exynos5250-snow.dts b/arch/arm/boot/dts/exynos5250-snow.dts
> index 1fa72cf..38e4cda 100644
> --- a/arch/arm/boot/dts/exynos5250-snow.dts
> +++ b/arch/arm/boot/dts/exynos5250-snow.dts
> @@ -691,6 +691,18 @@
>  	num-cs = <1>;
>  	cs-gpios = <&gpa2 5 0>;
>  	status = "okay";
> +		flash: m25p80@0 {

The indentation looks odd. This should be at the same level as "status".

> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +			compatible = "jedec,spi-nor";
> +			reg = <0>;
> +			spi-max-frequency = <40000000>;

So actually you wanted 133 MHz but as a workaround for DMA issue you use
40 MHz, right? Could you add here a small TODO note in comment about it?

Best regards,
Krzysztof
--
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/