ramips: add support for Spansion S34ML0[24]G2 flash

Signed-off-by: John Crispin <blogic@openwrt.org>

SVN-Revision: 47880

target/linux/ramips/patches-4.3/0901-spansion_nand_id_fix.patch

@@ -0,0 +1,43 @@
+From 8b61a1a33e41456ebeafa0ebe7ec0fccf859861e Mon Sep 17 00:00:00 2001
+From: Nikolay Martynov <mar.kolya@gmail.com>
+Date: Wed, 25 Nov 2015 20:43:46 -0500
+Subject: [PATCH] mtd: nand: Fix Spansion sparearea size detection
+
+According to datasheet S34ML02G2 and S34ML04G2 have
+larger sparea area size than was detected.
+
+Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
+---
+ drivers/mtd/nand/nand_base.c | 9 +++++++++
+ 1 file changed, 9 insertions(+)
+
+--- a/drivers/mtd/nand/nand_base.c
++++ b/drivers/mtd/nand/nand_base.c
+@@ -3422,6 +3422,7 @@ static void nand_decode_ext_id(struct mt
+ 	/*
+ 	 * Field definitions are in the following datasheets:
+ 	 * Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
++	 *                          Spansion S34ML02G2 (p.33)
+ 	 * New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
+ 	 * Hynix MLC   (6 byte ID): Hynix H27UBG8T2B (p.22)
+ 	 *
+@@ -3519,6 +3520,19 @@ static void nand_decode_ext_id(struct mt
+ 		*busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
+ 
+ 		/*
++		 * Spansion S34ML0[24]G2 have oobsize twice as large
++		 * as S34ML01G2 encoded in the same bit. We
++		 * differinciate them by their ID length
++		 */
++		if (id_data[0] == NAND_MFR_AMD
++		    		&& (id_data[1] == 0xda
++				 || id_data[1] == 0xdc
++				 || id_data[1] == 0xca
++				 || id_data[1] == 0xcc)) {
++			mtd->oobsize *= 2;
++		}
++
++		/*
+ 		 * Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per
+ 		 * 512B page. For Toshiba SLC, we decode the 5th/6th byte as
+ 		 * follows: