linux-kernel - [PATCH 2/3] ARM: OMAP2+: GPMC: Support Software ECC scheme via DT

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:	Tue, 5 Aug 2014 13:11:21 +0300
From:	Roger Quadros <rogerq@...com>
To:	<computersforpeace@...il.com>, <tony@...mide.com>
CC:	<balbi@...com>, <ezequiel.garcia@...e-electrons.com>,
	<pekon.gupta@...il.com>, <artem.bityutskiy@...ux.intel.com>,
	<dwmw2@...radead.org>, <jg1.han@...sung.com>,
	<linux-mtd@...ts.infradead.org>, <linux-omap@...r.kernel.org>,
	<linux-kernel@...r.kernel.org>, Roger Quadros <rogerq@...com>
Subject: [PATCH 2/3] ARM: OMAP2+: GPMC: Support Software ECC scheme via DT

For v3.14 and prior, 1-bit Hamming code ECC via software was the
default choice for some boards e.g. 3430sdp.
Commit ac65caf514ec in v3.15 changed the behaviour
to use 1-bit Hamming code via Hardware using a different ECC layout
i.e. (ROM code layout) than what is used by software ECC.

This ECC layout change causes NAND filesystems created in v3.14
and prior to be unusable in v3.15 and later. So don't mark "sw" scheme
as deperecated and support it.

Signed-off-by: Roger Quadros <rogerq@...com>
---
 Documentation/devicetree/bindings/mtd/gpmc-nand.txt | 2 +-
 arch/arm/mach-omap2/gpmc.c                          | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
index 65f4f7c..ee654e9 100644
--- a/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/gpmc-nand.txt
@@ -22,7 +22,7 @@ Optional properties:
 				width of 8 is assumed.
 
  - ti,nand-ecc-opt:		A string setting the ECC layout to use. One of:
-		"sw"		<deprecated> use "ham1" instead
+		"sw"		1-bit Hamming ecc code via software
 		"hw"		<deprecated> use "ham1" instead
 		"hw-romcode"	<deprecated> use "ham1" instead
 		"ham1"		1-bit Hamming ecc code
diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index 8bc1338..9f42d54 100644
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -1403,8 +1403,11 @@ static int gpmc_probe_nand_child(struct platform_device *pdev,
 		pr_err("%s: ti,nand-ecc-opt not found\n", __func__);
 		return -ENODEV;
 	}
-	if (!strcmp(s, "ham1") || !strcmp(s, "sw") ||
-		!strcmp(s, "hw") || !strcmp(s, "hw-romcode"))
+
+	if (!strcmp(s, "sw"))
+		gpmc_nand_data->ecc_opt = OMAP_ECC_HAM1_CODE_SW;
+	else if (!strcmp(s, "ham1") ||
+		 !strcmp(s, "hw") || !strcmp(s, "hw-romcode"))
 		gpmc_nand_data->ecc_opt =
 				OMAP_ECC_HAM1_CODE_HW;
 	else if (!strcmp(s, "bch4"))
-- 
1.8.3.2

--
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/