linux-kernel - [PATCH v2 2/5] Documentation: mtd: add a DT property to set the number of dummy cycles

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: <8119e3b46b91e43c10466b2400c6938a113b1c02.1437569902.git.cyrille.pitchen@atmel.com>
Date:	Wed, 22 Jul 2015 15:17:07 +0200
From:	Cyrille Pitchen <cyrille.pitchen@...el.com>
To:	<nicolas.ferre@...el.com>, <broonie@...nel.org>,
	<linux-spi@...r.kernel.org>, <dwmw2@...radead.org>,
	<computersforpeace@...il.com>, <zajec5@...il.com>,
	<beanhuo@...ron.com>, <juhosg@...nwrt.org>, <marex@...x.de>,
	<shijie.huang@...el.com>, <ben@...adent.org.uk>
CC:	<linux-kernel@...r.kernel.org>,
	<linux-arm-kernel@...ts.infradead.org>,
	<devicetree@...r.kernel.org>, <robh+dt@...nel.org>,
	<pawel.moll@....com>, <mark.rutland@....com>,
	<ijc+devicetree@...lion.org.uk>, <galak@...eaurora.org>,
	<linux-mtd@...ts.infradead.org>,
	Cyrille Pitchen <cyrille.pitchen@...el.com>
Subject: [PATCH v2 2/5] Documentation: mtd: add a DT property to set the number of dummy cycles

Depending on the SPI clock frequency, the Fast Read op code and the
Single/Dual Data Rate mode, the number of dummy cycles can be tuned to
improve transfer speed.
The actual number of dummy cycles is specific for each memory model and is
provided by the manufacturer thanks to the memory datasheet.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@...el.com>
---
 Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
index 2bee68103b01..4387567d8024 100644
--- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
+++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.txt
@@ -19,6 +19,11 @@ Optional properties:
                    all chips and support for it can not be detected at runtime.
                    Refer to your chips' datasheet to check if this is supported
                    by your chip.
+- m25p,num-dummy-cycles : Set the number of dummy cycles for Fast Read commands.
+                          Depending on the manufacturer additional dedicated
+                          commands are sent to the flash memory so the
+                          controller and the memory can agree on the number of
+                          dummy cycles to use.
 
 Example:
 
@@ -29,4 +34,5 @@ Example:
 		reg = <0>;
 		spi-max-frequency = <40000000>;
 		m25p,fast-read;
+		m25p,num-dummy-cycles = <8>;
 	};
-- 
1.8.2.2

--
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/