[KR Kim <kr.kim@skyhighmemory.com>]

Feat: Add SkyHigh Memory Patch code

Add SPI Nand Patch code of SkyHigh Memory
- Add company dependent code with 'skyhigh.c'
- Insert into 'core.c' so that 'always ECC on'

commit 6061b97a830af8cb5fd0917e833e779451f9046a (HEAD -> master)
Author: KR Kim <kr.kim@skyhighmemory.com>
Date:   Thu Mar 7 13:24:11 2024 +0900

    SPI Nand Patch code of SkyHigh Momory

    Signed-off-by: KR Kim <kr.kim@skyhighmemory.com>

From 6061b97a830af8cb5fd0917e833e779451f9046a Mon Sep 17 00:00:00 2001
From: KR Kim <kr.kim@skyhighmemory.com>
Date: Thu, 7 Mar 2024 13:24:11 +0900
Subject: [PATCH] SPI Nand Patch code of SkyHigh Memory

---
 drivers/mtd/nand/spi/Makefile  |   2 +-
 drivers/mtd/nand/spi/core.c    |   7 +-
 drivers/mtd/nand/spi/skyhigh.c | 155 +++++++++++++++++++++++++++++++++
 include/linux/mtd/spinand.h    |   3 +
 4 files changed, 165 insertions(+), 2 deletions(-)
 mode change 100644 => 100755 drivers/mtd/nand/spi/Makefile
 mode change 100644 => 100755 drivers/mtd/nand/spi/core.c
 create mode 100644 drivers/mtd/nand/spi/skyhigh.c
 mode change 100644 => 100755 include/linux/mtd/spinand.h

diff --git a/drivers/mtd/nand/spi/Makefile b/drivers/mtd/nand/spi/Makefile
old mode 100644
new mode 100755
index 19cc77288ebb..1e61ab21893a
--- a/drivers/mtd/nand/spi/Makefile
+++ b/drivers/mtd/nand/spi/Makefile
@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: GPL-2.0
 spinand-objs := core.o alliancememory.o ato.o esmt.o foresee.o gigadevice.o macronix.o
-spinand-objs += micron.o paragon.o toshiba.o winbond.o xtx.o
+spinand-objs += micron.o paragon.o skyhigh.o toshiba.o winbond.o xtx.o
 obj-$(CONFIG_MTD_SPI_NAND) += spinand.o
diff --git a/drivers/mtd/nand/spi/core.c b/drivers/mtd/nand/spi/core.c
old mode 100644
new mode 100755
index e0b6715e5dfe..e3f0a7544ba4
--- a/drivers/mtd/nand/spi/core.c
+++ b/drivers/mtd/nand/spi/core.c
@@ -34,7 +34,7 @@ static int spinand_read_reg_op(struct spinand_device *spinand, u8 reg, u8 *val)
 	return 0;
 }
 
-static int spinand_write_reg_op(struct spinand_device *spinand, u8 reg, u8 val)
+int spinand_write_reg_op(struct spinand_device *spinand, u8 reg, u8 val)
 {
 	struct spi_mem_op op = SPINAND_SET_FEATURE_OP(reg,
 						      spinand->scratchbuf);
@@ -196,6 +196,10 @@ static int spinand_init_quad_enable(struct spinand_device *spinand)
 static int spinand_ecc_enable(struct spinand_device *spinand,
 			      bool enable)
 {
+	/* SHM : always ECC enable */
+	if (spinand->flags & SPINAND_ON_DIE_ECC_MANDATORY)
+		return 0;
+
 	return spinand_upd_cfg(spinand, CFG_ECC_ENABLE,
 			       enable ? CFG_ECC_ENABLE : 0);
 }
@@ -945,6 +949,7 @@ static const struct spinand_manufacturer *spinand_manufacturers[] = {
 	&macronix_spinand_manufacturer,
 	&micron_spinand_manufacturer,
 	&paragon_spinand_manufacturer,
+	&skyhigh_spinand_manufacturer,
 	&toshiba_spinand_manufacturer,
 	&winbond_spinand_manufacturer,
 	&xtx_spinand_manufacturer,
diff --git a/drivers/mtd/nand/spi/skyhigh.c b/drivers/mtd/nand/spi/skyhigh.c
new file mode 100644
index 000000000000..92e7572094ff
--- /dev/null
+++ b/drivers/mtd/nand/spi/skyhigh.c
@@ -0,0 +1,155 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2022 SkyHigh Memory Limited
+ *
+ * Author: Takahiro Kuwano <takahiro.kuwano@infineon.com>
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/mtd/spinand.h>
+
+#define SPINAND_MFR_SKYHIGH		0x01
+
+#define SKYHIGH_STATUS_ECC_1TO2_BITFLIPS	(1 << 4)
+#define SKYHIGH_STATUS_ECC_3TO6_BITFLIPS	(2 << 4)
+#define SKYHIGH_STATUS_ECC_UNCOR_ERROR  	(3 << 4)
+
+#define SKYHIGH_CONFIG_PROTECT_EN	BIT(1)
+
+static SPINAND_OP_VARIANTS(read_cache_variants,
+		SPINAND_PAGE_READ_FROM_CACHE_QUADIO_OP(0, 4, NULL, 0),
+		SPINAND_PAGE_READ_FROM_CACHE_X4_OP(0, 1, NULL, 0),
+		SPINAND_PAGE_READ_FROM_CACHE_DUALIO_OP(0, 2, NULL, 0),
+		SPINAND_PAGE_READ_FROM_CACHE_X2_OP(0, 1, NULL, 0),
+		SPINAND_PAGE_READ_FROM_CACHE_OP(true, 0, 1, NULL, 0),
+		SPINAND_PAGE_READ_FROM_CACHE_OP(false, 0, 1, NULL, 0));
+
+static SPINAND_OP_VARIANTS(write_cache_variants,
+		SPINAND_PROG_LOAD_X4(true, 0, NULL, 0),
+		SPINAND_PROG_LOAD(true, 0, NULL, 0));
+
+static SPINAND_OP_VARIANTS(update_cache_variants,
+		SPINAND_PROG_LOAD_X4(false, 0, NULL, 0),
+		SPINAND_PROG_LOAD(false, 0, NULL, 0));
+
+static int skyhigh_spinand_ooblayout_ecc(struct mtd_info *mtd, int section,
+					 struct mtd_oob_region *region)
+{
+	if (section)
+		return -ERANGE;
+
+	/* SkyHigh's ecc parity is stored in the internal hidden area and is not needed for them. */
+	region->length = 0;
+	region->offset = mtd->oobsize;
+
+	return 0;
+}
+
+static int skyhigh_spinand_ooblayout_free(struct mtd_info *mtd, int section,
+					  struct mtd_oob_region *region)
+{
+	if (section)
+		return -ERANGE;
+
+	region->length = mtd->oobsize - 2;
+	region->offset = 2;
+
+	return 0;
+}
+
+static const struct mtd_ooblayout_ops skyhigh_spinand_ooblayout = {
+	.ecc = skyhigh_spinand_ooblayout_ecc,
+	.free = skyhigh_spinand_ooblayout_free,
+};
+
+static int skyhigh_spinand_ecc_get_status(struct spinand_device *spinand,
+				  u8 status)
+{
+	/* SHM
+	 * 00 : No bit-flip
+	 * 01 : 1-2 errors corrected
+	 * 10 : 3-6 errors corrected         
+	 * 11 : uncorrectable
+	 */
+
+	switch (status & STATUS_ECC_MASK) {
+	case STATUS_ECC_NO_BITFLIPS:
+		return 0;
+
+	case SKYHIGH_STATUS_ECC_1TO2_BITFLIPS:
+		return 2;
+
+ 	case SKYHIGH_STATUS_ECC_3TO6_BITFLIPS:
+		return 6; 
+
+ 	case SKYHIGH_STATUS_ECC_UNCOR_ERROR:
+		return -EBADMSG;;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+static const struct spinand_info skyhigh_spinand_table[] = {
+	SPINAND_INFO("S35ML01G301",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x15),
+		     NAND_MEMORG(1, 2048, 64, 64, 1024, 20, 1, 1, 1),
+		     NAND_ECCREQ(6, 32),
+		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
+					      &write_cache_variants,
+					      &update_cache_variants),
+		     SPINAND_ON_DIE_ECC_MANDATORY,
+		     SPINAND_ECCINFO(&skyhigh_spinand_ooblayout,
+		     		     skyhigh_spinand_ecc_get_status)),
+	SPINAND_INFO("S35ML01G300",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x14),
+		     NAND_MEMORG(1, 2048, 128, 64, 1024, 20, 1, 1, 1),
+		     NAND_ECCREQ(6, 32),
+		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
+					      &write_cache_variants,
+					      &update_cache_variants),
+		     SPINAND_ON_DIE_ECC_MANDATORY,
+		     SPINAND_ECCINFO(&skyhigh_spinand_ooblayout,
+		     		     skyhigh_spinand_ecc_get_status)),
+	SPINAND_INFO("S35ML02G300",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x25),
+		     NAND_MEMORG(1, 2048, 128, 64, 2048, 40, 2, 1, 1),
+		     NAND_ECCREQ(6, 32),
+		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
+					      &write_cache_variants,
+					      &update_cache_variants),
+		     SPINAND_ON_DIE_ECC_MANDATORY,
+		     SPINAND_ECCINFO(&skyhigh_spinand_ooblayout,
+		     		     skyhigh_spinand_ecc_get_status)),
+	SPINAND_INFO("S35ML04G300",
+		     SPINAND_ID(SPINAND_READID_METHOD_OPCODE_DUMMY, 0x35),
+		     NAND_MEMORG(1, 2048, 128, 64, 4096, 80, 2, 1, 1),
+		     NAND_ECCREQ(6, 32),
+		     SPINAND_INFO_OP_VARIANTS(&read_cache_variants,
+					      &write_cache_variants,
+					      &update_cache_variants),
+		     SPINAND_ON_DIE_ECC_MANDATORY,
+		     SPINAND_ECCINFO(&skyhigh_spinand_ooblayout,
+		     		     skyhigh_spinand_ecc_get_status)),
+};
+
+static int skyhigh_spinand_init(struct spinand_device *spinand)
+{
+	return spinand_write_reg_op(spinand, REG_BLOCK_LOCK,
+				    SKYHIGH_CONFIG_PROTECT_EN);
+}
+
+static const struct spinand_manufacturer_ops skyhigh_spinand_manuf_ops = {
+	.init = skyhigh_spinand_init,
+ };
+
+const struct spinand_manufacturer skyhigh_spinand_manufacturer = {
+	.id = SPINAND_MFR_SKYHIGH,
+	.name = "SkyHigh",
+	.chips = skyhigh_spinand_table,
+	.nchips = ARRAY_SIZE(skyhigh_spinand_table),
+	.ops = &skyhigh_spinand_manuf_ops,
+};
diff --git a/include/linux/mtd/spinand.h b/include/linux/mtd/spinand.h
old mode 100644
new mode 100755
index badb4c1ac079..0e135076df24
--- a/include/linux/mtd/spinand.h
+++ b/include/linux/mtd/spinand.h
@@ -268,6 +268,7 @@ extern const struct spinand_manufacturer gigadevice_spinand_manufacturer;
 extern const struct spinand_manufacturer macronix_spinand_manufacturer;
 extern const struct spinand_manufacturer micron_spinand_manufacturer;
 extern const struct spinand_manufacturer paragon_spinand_manufacturer;
+extern const struct spinand_manufacturer skyhigh_spinand_manufacturer;
 extern const struct spinand_manufacturer toshiba_spinand_manufacturer;
 extern const struct spinand_manufacturer winbond_spinand_manufacturer;
 extern const struct spinand_manufacturer xtx_spinand_manufacturer;
@@ -312,6 +313,7 @@ struct spinand_ecc_info {
 
 #define SPINAND_HAS_QE_BIT		BIT(0)
 #define SPINAND_HAS_CR_FEAT_BIT		BIT(1)
+#define SPINAND_ON_DIE_ECC_MANDATORY	BIT(2)	/* SHM */
 
 /**
  * struct spinand_ondie_ecc_conf - private SPI-NAND on-die ECC engine structure
@@ -518,5 +520,6 @@ int spinand_match_and_init(struct spinand_device *spinand,
 
 int spinand_upd_cfg(struct spinand_device *spinand, u8 mask, u8 val);
 int spinand_select_target(struct spinand_device *spinand, unsigned int target);
+int spinand_write_reg_op(struct spinand_device *spinand, u8 reg, u8 val);
 
 #endif /* __LINUX_MTD_SPINAND_H */
-- 
2.34.1