mtd: nand: add NAND driver "library" for Broadcom STB NAND controller

This core originated in Set-Top Box chips (BCM7xxx) but is used in a
variety of other Broadcom chips, including some BCM63xxx, BCM33xx, and
iProc/Cygnus. It's been used only on ARM and MIPS SoCs, so restrict it
to those architectures.

There are multiple revisions of this core throughout the years, and
almost every version broke register compatibility in some small way, but
with some effort, this driver is able to support v4.0, v5.0, v6.x, v7.0,
and v7.1. It's been tested on v5.0, v6.0, v6.1, v7.0, and v7.1 recently,
so there hopefully are no more lurking inconsistencies.

This patch adds just some library support, on which platform drivers can
be built.

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>

1 files changed, 2195 insertions, 0 deletions

diff --git a/drivers/mtd/nand/brcmnand/brcmnand.c b/drivers/mtd/nand/brcmnand/brcmnand.c
new file mode 100644
index 000000000000..fb81aac8d4ef
--- /dev/null
+++ b/drivers/mtd/nand/brcmnand/brcmnand.c
@@ -0,0 +1,2195 @@
+/*
+ * Copyright © 2010-2015 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/version.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/dma-mapping.h>
+#include <linux/ioport.h>
+#include <linux/bug.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/mm.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+#include <linux/of.h>
+#include <linux/of_mtd.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/log2.h>
+
+#include "brcmnand.h"
+
+/*
+ * This flag controls if WP stays on between erase/write commands to mitigate
+ * flash corruption due to power glitches. Values:
+ * 0: NAND_WP is not used or not available
+ * 1: NAND_WP is set by default, cleared for erase/write operations
+ * 2: NAND_WP is always cleared
+ */
+static int wp_on = 1;
+module_param(wp_on, int, 0444);
+
+/***********************************************************************
+ * Definitions
+ ***********************************************************************/
+
+#define DRV_NAME			"brcmnand"
+
+#define CMD_NULL			0x00
+#define CMD_PAGE_READ			0x01
+#define CMD_SPARE_AREA_READ		0x02
+#define CMD_STATUS_READ			0x03
+#define CMD_PROGRAM_PAGE		0x04
+#define CMD_PROGRAM_SPARE_AREA		0x05
+#define CMD_COPY_BACK			0x06
+#define CMD_DEVICE_ID_READ		0x07
+#define CMD_BLOCK_ERASE			0x08
+#define CMD_FLASH_RESET			0x09
+#define CMD_BLOCKS_LOCK			0x0a
+#define CMD_BLOCKS_LOCK_DOWN		0x0b
+#define CMD_BLOCKS_UNLOCK		0x0c
+#define CMD_READ_BLOCKS_LOCK_STATUS	0x0d
+#define CMD_PARAMETER_READ		0x0e
+#define CMD_PARAMETER_CHANGE_COL	0x0f
+#define CMD_LOW_LEVEL_OP		0x10
+
+struct brcm_nand_dma_desc {
+	u32 next_desc;
+	u32 next_desc_ext;
+	u32 cmd_irq;
+	u32 dram_addr;
+	u32 dram_addr_ext;
+	u32 tfr_len;
+	u32 total_len;
+	u32 flash_addr;
+	u32 flash_addr_ext;
+	u32 cs;
+	u32 pad2[5];
+	u32 status_valid;
+} __packed;
+
+/* Bitfields for brcm_nand_dma_desc::status_valid */
+#define FLASH_DMA_ECC_ERROR	(1 << 8)
+#define FLASH_DMA_CORR_ERROR	(1 << 9)
+
+/* 512B flash cache in the NAND controller HW */
+#define FC_SHIFT		9U
+#define FC_BYTES		512U
+#define FC_WORDS		(FC_BYTES >> 2)
+
+#define BRCMNAND_MIN_PAGESIZE	512
+#define BRCMNAND_MIN_BLOCKSIZE	(8 * 1024)
+#define BRCMNAND_MIN_DEVSIZE	(4ULL * 1024 * 1024)
+
+/* Controller feature flags */
+enum {
+	BRCMNAND_HAS_1K_SECTORS			= BIT(0),
+	BRCMNAND_HAS_PREFETCH			= BIT(1),
+	BRCMNAND_HAS_CACHE_MODE			= BIT(2),
+	BRCMNAND_HAS_WP				= BIT(3),
+};
+
+struct brcmnand_controller {
+	struct device		*dev;
+	struct nand_hw_control	controller;
+	void __iomem		*nand_base;
+	void __iomem		*nand_fc; /* flash cache */
+	void __iomem		*flash_dma_base;
+	unsigned int		irq;
+	unsigned int		dma_irq;
+	int			nand_version;
+
+	int			cmd_pending;
+	bool			dma_pending;
+	struct completion	done;
+	struct completion	dma_done;
+
+	/* List of NAND hosts (one for each chip-select) */
+	struct list_head host_list;
+
+	struct brcm_nand_dma_desc *dma_desc;
+	dma_addr_t		dma_pa;
+
+	/* in-memory cache of the FLASH_CACHE, used only for some commands */
+	u32			flash_cache[FC_WORDS];
+
+	/* Controller revision details */
+	const u16		*reg_offsets;
+	unsigned int		reg_spacing; /* between CS1, CS2, ... regs */
+	const u8		*cs_offsets; /* within each chip-select */
+	const u8		*cs0_offsets; /* within CS0, if different */
+	unsigned int		max_block_size;
+	const unsigned int	*block_sizes;
+	unsigned int		max_page_size;
+	const unsigned int	*page_sizes;
+	unsigned int		max_oob;
+	u32			features;
+
+	/* for low-power standby/resume only */
+	u32			nand_cs_nand_select;
+	u32			nand_cs_nand_xor;
+	u32			corr_stat_threshold;
+	u32			flash_dma_mode;
+};
+
+struct brcmnand_cfg {
+	u64			device_size;
+	unsigned int		block_size;
+	unsigned int		page_size;
+	unsigned int		spare_area_size;
+	unsigned int		device_width;
+	unsigned int		col_adr_bytes;
+	unsigned int		blk_adr_bytes;
+	unsigned int		ful_adr_bytes;
+	unsigned int		sector_size_1k;
+	unsigned int		ecc_level;
+	/* use for low-power standby/resume only */
+	u32			acc_control;
+	u32			config;
+	u32			config_ext;
+	u32			timing_1;
+	u32			timing_2;
+};
+
+struct brcmnand_host {
+	struct list_head	node;
+	struct device_node	*of_node;
+
+	struct nand_chip	chip;
+	struct mtd_info		mtd;
+	struct platform_device	*pdev;
+	int			cs;
+
+	unsigned int		last_cmd;
+	unsigned int		last_byte;
+	u64			last_addr;
+	struct brcmnand_cfg	hwcfg;
+	struct brcmnand_controller *ctrl;
+};
+
+enum brcmnand_reg {
+	BRCMNAND_CMD_START = 0,
+	BRCMNAND_CMD_EXT_ADDRESS,
+	BRCMNAND_CMD_ADDRESS,
+	BRCMNAND_INTFC_STATUS,
+	BRCMNAND_CS_SELECT,
+	BRCMNAND_CS_XOR,
+	BRCMNAND_LL_OP,
+	BRCMNAND_CS0_BASE,
+	BRCMNAND_CS1_BASE,		/* CS1 regs, if non-contiguous */
+	BRCMNAND_CORR_THRESHOLD,
+	BRCMNAND_CORR_THRESHOLD_EXT,
+	BRCMNAND_UNCORR_COUNT,
+	BRCMNAND_CORR_COUNT,
+	BRCMNAND_CORR_EXT_ADDR,
+	BRCMNAND_CORR_ADDR,
+	BRCMNAND_UNCORR_EXT_ADDR,
+	BRCMNAND_UNCORR_ADDR,
+	BRCMNAND_SEMAPHORE,
+	BRCMNAND_ID,
+	BRCMNAND_ID_EXT,
+	BRCMNAND_LL_RDATA,
+	BRCMNAND_OOB_READ_BASE,
+	BRCMNAND_OOB_READ_10_BASE,	/* offset 0x10, if non-contiguous */
+	BRCMNAND_OOB_WRITE_BASE,
+	BRCMNAND_OOB_WRITE_10_BASE,	/* offset 0x10, if non-contiguous */
+	BRCMNAND_FC_BASE,
+};
+
+/* BRCMNAND v4.0 */
+static const u16 brcmnand_regs_v40[] = {
+	[BRCMNAND_CMD_START]		=  0x04,
+	[BRCMNAND_CMD_EXT_ADDRESS]	=  0x08,
+	[BRCMNAND_CMD_ADDRESS]		=  0x0c,
+	[BRCMNAND_INTFC_STATUS]		=  0x6c,
+	[BRCMNAND_CS_SELECT]		=  0x14,
+	[BRCMNAND_CS_XOR]		=  0x18,
+	[BRCMNAND_LL_OP]		= 0x178,
+	[BRCMNAND_CS0_BASE]		=  0x40,
+	[BRCMNAND_CS1_BASE]		=  0xd0,
+	[BRCMNAND_CORR_THRESHOLD]	=  0x84,
+	[BRCMNAND_CORR_THRESHOLD_EXT]	=     0,
+	[BRCMNAND_UNCORR_COUNT]		=     0,
+	[BRCMNAND_CORR_COUNT]		=     0,
+	[BRCMNAND_CORR_EXT_ADDR]	=  0x70,
+	[BRCMNAND_CORR_ADDR]		=  0x74,
+	[BRCMNAND_UNCORR_EXT_ADDR]	=  0x78,
+	[BRCMNAND_UNCORR_ADDR]		=  0x7c,
+	[BRCMNAND_SEMAPHORE]		=  0x58,
+	[BRCMNAND_ID]			=  0x60,
+	[BRCMNAND_ID_EXT]		=  0x64,
+	[BRCMNAND_LL_RDATA]		= 0x17c,
+	[BRCMNAND_OOB_READ_BASE]	=  0x20,
+	[BRCMNAND_OOB_READ_10_BASE]	= 0x130,
+	[BRCMNAND_OOB_WRITE_BASE]	=  0x30,
+	[BRCMNAND_OOB_WRITE_10_BASE]	=     0,
+	[BRCMNAND_FC_BASE]		= 0x200,
+};
+
+/* BRCMNAND v5.0 */
+static const u16 brcmnand_regs_v50[] = {
+	[BRCMNAND_CMD_START]		=  0x04,
+	[BRCMNAND_CMD_EXT_ADDRESS]	=  0x08,
+	[BRCMNAND_CMD_ADDRESS]		=  0x0c,
+	[BRCMNAND_INTFC_STATUS]		=  0x6c,
+	[BRCMNAND_CS_SELECT]		=  0x14,
+	[BRCMNAND_CS_XOR]		=  0x18,
+	[BRCMNAND_LL_OP]		= 0x178,
+	[BRCMNAND_CS0_BASE]		=  0x40,
+	[BRCMNAND_CS1_BASE]		=  0xd0,
+	[BRCMNAND_CORR_THRESHOLD]	=  0x84,
+	[BRCMNAND_CORR_THRESHOLD_EXT]	=     0,
+	[BRCMNAND_UNCORR_COUNT]		=     0,
+	[BRCMNAND_CORR_COUNT]		=     0,
+	[BRCMNAND_CORR_EXT_ADDR]	=  0x70,
+	[BRCMNAND_CORR_ADDR]		=  0x74,
+	[BRCMNAND_UNCORR_EXT_ADDR]	=  0x78,
+	[BRCMNAND_UNCORR_ADDR]		=  0x7c,
+	[BRCMNAND_SEMAPHORE]		=  0x58,
+	[BRCMNAND_ID]			=  0x60,
+	[BRCMNAND_ID_EXT]		=  0x64,
+	[BRCMNAND_LL_RDATA]		= 0x17c,
+	[BRCMNAND_OOB_READ_BASE]	=  0x20,
+	[BRCMNAND_OOB_READ_10_BASE]	= 0x130,
+	[BRCMNAND_OOB_WRITE_BASE]	=  0x30,
+	[BRCMNAND_OOB_WRITE_10_BASE]	= 0x140,
+	[BRCMNAND_FC_BASE]		= 0x200,
+};
+
+/* BRCMNAND v6.0 - v7.1 */
+static const u16 brcmnand_regs_v60[] = {
+	[BRCMNAND_CMD_START]		=  0x04,
+	[BRCMNAND_CMD_EXT_ADDRESS]	=  0x08,
+	[BRCMNAND_CMD_ADDRESS]		=  0x0c,
+	[BRCMNAND_INTFC_STATUS]		=  0x14,
+	[BRCMNAND_CS_SELECT]		=  0x18,
+	[BRCMNAND_CS_XOR]		=  0x1c,
+	[BRCMNAND_LL_OP]		=  0x20,
+	[BRCMNAND_CS0_BASE]		=  0x50,
+	[BRCMNAND_CS1_BASE]		=     0,
+	[BRCMNAND_CORR_THRESHOLD]	=  0xc0,
+	[BRCMNAND_CORR_THRESHOLD_EXT]	=  0xc4,
+	[BRCMNAND_UNCORR_COUNT]		=  0xfc,
+	[BRCMNAND_CORR_COUNT]		= 0x100,
+	[BRCMNAND_CORR_EXT_ADDR]	= 0x10c,
+	[BRCMNAND_CORR_ADDR]		= 0x110,
+	[BRCMNAND_UNCORR_EXT_ADDR]	= 0x114,
+	[BRCMNAND_UNCORR_ADDR]		= 0x118,
+	[BRCMNAND_SEMAPHORE]		= 0x150,
+	[BRCMNAND_ID]			= 0x194,
+	[BRCMNAND_ID_EXT]		= 0x198,
+	[BRCMNAND_LL_RDATA]		= 0x19c,
+	[BRCMNAND_OOB_READ_BASE]	= 0x200,
+	[BRCMNAND_OOB_READ_10_BASE]	=     0,
+	[BRCMNAND_OOB_WRITE_BASE]	= 0x280,
+	[BRCMNAND_OOB_WRITE_10_BASE]	=     0,
+	[BRCMNAND_FC_BASE]		= 0x400,
+};
+
+enum brcmnand_cs_reg {
+	BRCMNAND_CS_CFG_EXT = 0,
+	BRCMNAND_CS_CFG,
+	BRCMNAND_CS_ACC_CONTROL,
+	BRCMNAND_CS_TIMING1,
+	BRCMNAND_CS_TIMING2,
+};
+
+/* Per chip-select offsets for v7.1 */
+static const u8 brcmnand_cs_offsets_v71[] = {
+	[BRCMNAND_CS_ACC_CONTROL]	= 0x00,
+	[BRCMNAND_CS_CFG_EXT]		= 0x04,
+	[BRCMNAND_CS_CFG]		= 0x08,
+	[BRCMNAND_CS_TIMING1]		= 0x0c,
+	[BRCMNAND_CS_TIMING2]		= 0x10,
+};
+
+/* Per chip-select offsets for pre v7.1, except CS0 on <= v5.0 */
+static const u8 brcmnand_cs_offsets[] = {
+	[BRCMNAND_CS_ACC_CONTROL]	= 0x00,
+	[BRCMNAND_CS_CFG_EXT]		= 0x04,
+	[BRCMNAND_CS_CFG]		= 0x04,
+	[BRCMNAND_CS_TIMING1]		= 0x08,
+	[BRCMNAND_CS_TIMING2]		= 0x0c,
+};
+
+/* Per chip-select offset for <= v5.0 on CS0 only */
+static const u8 brcmnand_cs_offsets_cs0[] = {
+	[BRCMNAND_CS_ACC_CONTROL]	= 0x00,
+	[BRCMNAND_CS_CFG_EXT]		= 0x08,
+	[BRCMNAND_CS_CFG]		= 0x08,
+	[BRCMNAND_CS_TIMING1]		= 0x10,
+	[BRCMNAND_CS_TIMING2]		= 0x14,
+};
+
+/* BRCMNAND_INTFC_STATUS */
+enum {
+	INTFC_FLASH_STATUS		= GENMASK(7, 0),
+
+	INTFC_ERASED			= BIT(27),
+	INTFC_OOB_VALID			= BIT(28),
+	INTFC_CACHE_VALID		= BIT(29),
+	INTFC_FLASH_READY		= BIT(30),
+	INTFC_CTLR_READY		= BIT(31),
+};
+
+static inline u32 nand_readreg(struct brcmnand_controller *ctrl, u32 offs)
+{
+	return brcmnand_readl(ctrl->nand_base + offs);
+}
+
+static inline void nand_writereg(struct brcmnand_controller *ctrl, u32 offs,
+				 u32 val)
+{
+	brcmnand_writel(val, ctrl->nand_base + offs);
+}
+
+static int brcmnand_revision_init(struct brcmnand_controller *ctrl)
+{
+	static const unsigned int block_sizes_v6[] = { 8, 16, 128, 256, 512, 1024, 2048, 0 };
+	static const unsigned int block_sizes_v4[] = { 16, 128, 8, 512, 256, 1024, 2048, 0 };
+	static const unsigned int page_sizes[] = { 512, 2048, 4096, 8192, 0 };
+
+	ctrl->nand_version = nand_readreg(ctrl, 0) & 0xffff;
+
+	/* Only support v4.0+? */
+	if (ctrl->nand_version < 0x0400) {
+		dev_err(ctrl->dev, "version %#x not supported\n",
+			ctrl->nand_version);
+		return -ENODEV;
+	}
+
+	/* Register offsets */
+	if (ctrl->nand_version >= 0x0600)
+		ctrl->reg_offsets = brcmnand_regs_v60;
+	else if (ctrl->nand_version >= 0x0500)
+		ctrl->reg_offsets = brcmnand_regs_v50;
+	else if (ctrl->nand_version >= 0x0400)
+		ctrl->reg_offsets = brcmnand_regs_v40;
+
+	/* Chip-select stride */
+	if (ctrl->nand_version >= 0x0701)
+		ctrl->reg_spacing = 0x14;
+	else
+		ctrl->reg_spacing = 0x10;
+
+	/* Per chip-select registers */
+	if (ctrl->nand_version >= 0x0701) {
+		ctrl->cs_offsets = brcmnand_cs_offsets_v71;
+	} else {
+		ctrl->cs_offsets = brcmnand_cs_offsets;
+
+		/* v5.0 and earlier has a different CS0 offset layout */
+		if (ctrl->nand_version <= 0x0500)
+			ctrl->cs0_offsets = brcmnand_cs_offsets_cs0;
+	}
+
+	/* Page / block sizes */
+	if (ctrl->nand_version >= 0x0701) {
+		/* >= v7.1 use nice power-of-2 values! */
+		ctrl->max_page_size = 16 * 1024;
+		ctrl->max_block_size = 2 * 1024 * 1024;
+	} else {
+		ctrl->page_sizes = page_sizes;
+		if (ctrl->nand_version >= 0x0600)
+			ctrl->block_sizes = block_sizes_v6;
+		else
+			ctrl->block_sizes = block_sizes_v4;
+
+		if (ctrl->nand_version < 0x0400) {
+			ctrl->max_page_size = 4096;
+			ctrl->max_block_size = 512 * 1024;
+		}
+	}
+
+	/* Maximum spare area sector size (per 512B) */
+	if (ctrl->nand_version >= 0x0600)
+		ctrl->max_oob = 64;
+	else if (ctrl->nand_version >= 0x0500)
+		ctrl->max_oob = 32;
+	else
+		ctrl->max_oob = 16;
+
+	/* v6.0 and newer (except v6.1) have prefetch support */
+	if (ctrl->nand_version >= 0x0600 && ctrl->nand_version != 0x0601)
+		ctrl->features |= BRCMNAND_HAS_PREFETCH;
+
+	/*
+	 * v6.x has cache mode, but it's implemented differently. Ignore it for
+	 * now.
+	 */
+	if (ctrl->nand_version >= 0x0700)
+		ctrl->features |= BRCMNAND_HAS_CACHE_MODE;
+
+	if (ctrl->nand_version >= 0x0500)
+		ctrl->features |= BRCMNAND_HAS_1K_SECTORS;
+
+	if (ctrl->nand_version >= 0x0700)
+		ctrl->features |= BRCMNAND_HAS_WP;
+	else if (of_property_read_bool(ctrl->dev->of_node, "brcm,nand-has-wp"))
+		ctrl->features |= BRCMNAND_HAS_WP;
+
+	return 0;
+}
+
+static inline u32 brcmnand_read_reg(struct brcmnand_controller *ctrl,
+		enum brcmnand_reg reg)
+{
+	u16 offs = ctrl->reg_offsets[reg];
+
+	if (offs)
+		return nand_readreg(ctrl, offs);
+	else
+		return 0;
+}
+
+static inline void brcmnand_write_reg(struct brcmnand_controller *ctrl,
+				      enum brcmnand_reg reg, u32 val)
+{
+	u16 offs = ctrl->reg_offsets[reg];
+
+	if (offs)
+		nand_writereg(ctrl, offs, val);
+}
+
+static inline void brcmnand_rmw_reg(struct brcmnand_controller *ctrl,
+				    enum brcmnand_reg reg, u32 mask, unsigned
+				    int shift, u32 val)
+{
+	u32 tmp = brcmnand_read_reg(ctrl, reg);
+
+	tmp &= ~mask;
+	tmp |= val << shift;
+	brcmnand_write_reg(ctrl, reg, tmp);
+}
+
+static inline u32 brcmnand_read_fc(struct brcmnand_controller *ctrl, int word)
+{
+	return __raw_readl(ctrl->nand_fc + word * 4);
+}
+
+static inline void brcmnand_write_fc(struct brcmnand_controller *ctrl,
+				     int word, u32 val)
+{
+	__raw_writel(val, ctrl->nand_fc + word * 4);
+}
+
+static inline u16 brcmnand_cs_offset(struct brcmnand_controller *ctrl, int cs,
+				     enum brcmnand_cs_reg reg)
+{
+	u16 offs_cs0 = ctrl->reg_offsets[BRCMNAND_CS0_BASE];
+	u16 offs_cs1 = ctrl->reg_offsets[BRCMNAND_CS1_BASE];
+	u8 cs_offs;
+
+	if (cs == 0 && ctrl->cs0_offsets)
+		cs_offs = ctrl->cs0_offsets[reg];
+	else
+		cs_offs = ctrl->cs_offsets[reg];
+
+	if (cs && offs_cs1)
+		return offs_cs1 + (cs - 1) * ctrl->reg_spacing + cs_offs;
+
+	return offs_cs0 + cs * ctrl->reg_spacing + cs_offs;
+}
+
+static inline u32 brcmnand_count_corrected(struct brcmnand_controller *ctrl)
+{
+	if (ctrl->nand_version < 0x0600)
+		return 1;
+	return brcmnand_read_reg(ctrl, BRCMNAND_CORR_COUNT);
+}
+
+static void brcmnand_wr_corr_thresh(struct brcmnand_host *host, u8 val)
+{
+	struct brcmnand_controller *ctrl = host->ctrl;
+	unsigned int shift = 0, bits;
+	enum brcmnand_reg reg = BRCMNAND_CORR_THRESHOLD;
+	int cs = host->cs;
+
+	if (ctrl->nand_version >= 0x0600)
+		bits = 6;
+	else if (ctrl->nand_version >= 0x0500)
+		bits = 5;
+	else
+		bits = 4;
+
+	if (ctrl->nand_version >= 0x0600) {
+		if (cs >= 5)
+			reg = BRCMNAND_CORR_THRESHOLD_EXT;
+		shift = (cs % 5) * bits;
+	}
+	brcmnand_rmw_reg(ctrl, reg, (bits - 1) << shift, shift, val);
+}
+
+static inline int brcmnand_cmd_shift(struct brcmnand_controller *ctrl)
+{
+	if (ctrl->nand_version < 0x0700)
+		return 24;
+	return 0;
+}
+
+/***********************************************************************
+ * NAND ACC CONTROL bitfield
+ *
+ * Some bits have remained constant throughout hardware revision, while
+ * others have shifted around.
+ ***********************************************************************/
+
+/* Constant for all versions (where supported) */
+enum {
+	/* See BRCMNAND_HAS_CACHE_MODE */
+	ACC_CONTROL_CACHE_MODE				= BIT(22),
+
+	/* See BRCMNAND_HAS_PREFETCH */
+	ACC_CONTROL_PREFETCH				= BIT(23),
+
+	ACC_CONTROL_PAGE_HIT				= BIT(24),
+	ACC_CONTROL_WR_PREEMPT				= BIT(25),
+	ACC_CONTROL_PARTIAL_PAGE			= BIT(26),
+	ACC_CONTROL_RD_ERASED				= BIT(27),
+	ACC_CONTROL_FAST_PGM_RDIN			= BIT(28),
+	ACC_CONTROL_WR_ECC				= BIT(30),
+	ACC_CONTROL_RD_ECC				= BIT(31),
+};
+
+static inline u32 brcmnand_spare_area_mask(struct brcmnand_controller *ctrl)
+{
+	if (ctrl->nand_version >= 0x0600)
+		return GENMASK(6, 0);
+	else
+		return GENMASK(5, 0);
+}
+
+#define NAND_ACC_CONTROL_ECC_SHIFT	16
+
+static inline u32 brcmnand_ecc_level_mask(struct brcmnand_controller *ctrl)
+{
+	u32 mask = (ctrl->nand_version >= 0x0600) ? 0x1f : 0x0f;
+
+	return mask << NAND_ACC_CONTROL_ECC_SHIFT;
+}
+
+static void brcmnand_set_ecc_enabled(struct brcmnand_host *host, int en)
+{
+	struct brcmnand_controller *ctrl = host->ctrl;
+	u16 offs = brcmnand_cs_offset(ctrl, host->cs, BRCMNAND_CS_ACC_CONTROL);
+	u32 acc_control = nand_readreg(ctrl, offs);
+	u32 ecc_flags = ACC_CONTROL_WR_ECC | ACC_CONTROL_RD_ECC;
+
+	if (en) {
+		acc_control |= ecc_flags; /* enable RD/WR ECC */
+		acc_control |= host->hwcfg.ecc_level
+			       << NAND_ACC_CONTROL_ECC_SHIFT;
+	} else {
+		acc_control &= ~ecc_flags; /* disable RD/WR ECC */
+		acc_control &= ~brcmnand_ecc_level_mask(ctrl);
+	}
+
+	nand_writereg(ctrl, offs, acc_control);
+}
+
+static inline int brcmnand_sector_1k_shift(struct brcmnand_controller *ctrl)
+{
+	if (ctrl->nand_version >= 0x0600)
+		return 7;
+	else if (ctrl->nand_version >= 0x0500)
+		return 6;
+	else
+		return -1;
+}
+
+static int brcmnand_get_sector_size_1k(struct brcmnand_host *host)
+{
+	struct brcmnand_controller *ctrl = host->ctrl;
+	int shift = brcmnand_sector_1k_shift(ctrl);
+	u16 acc_control_offs = brcmnand_cs_offset(ctrl, host->cs,
+						  BRCMNAND_CS_ACC_CONTROL);
+
+	if (shift < 0)
+		return 0;
+
+	return (nand_readreg(ctrl, acc_control_offs) >> shift) & 0x1;
+}
+
+static void brcmnand_set_sector_size_1k(struct brcmnand_host *host, int val)
+{
+	struct brcmnand_controller *ctrl = host->ctrl;
+	int shift = brcmnand_sector_1k_shift(ctrl);
+	u16 acc_control_offs = brcmnand_cs_offset(ctrl, host->cs,
+						  BRCMNAND_CS_ACC_CONTROL);
+	u32 tmp;
+
+	if (shift < 0)
+		return;
+
+	tmp = nand_readreg(ctrl, acc_control_offs);
+	tmp &= ~(1 << shift);
+	tmp |= (!!val) << shift;
+	nand_writereg(ctrl, acc_control_offs, tmp);
+}
+
+/***********************************************************************
+ * CS_NAND_SELECT
+ ***********************************************************************/
+
+enum {
+	CS_SELECT_NAND_WP			= BIT(29),
+	CS_SELECT_AUTO_DEVICE_ID_CFG		= BIT(30),
+};
+
+static inline void brcmnand_set_wp(struct brcmnand_controller *ctrl, bool en)
+{
+	u32 val = en ? CS_SELECT_NAND_WP : 0;
+
+	brcmnand_rmw_reg(ctrl, BRCMNAND_CS_SELECT, CS_SELECT_NAND_WP, 0, val);
+}
+
+/***********************************************************************
+ * Flash DMA
+ ***********************************************************************/
+
+enum flash_dma_reg {
+	FLASH_DMA_REVISION		= 0x00,
+	FLASH_DMA_FIRST_DESC		= 0x04,
+	FLASH_DMA_FIRST_DESC_EXT	= 0x08,
+	FLASH_DMA_CTRL			= 0x0c,
+	FLASH_DMA_MODE			= 0x10,
+	FLASH_DMA_STATUS		= 0x14,
+	FLASH_DMA_INTERRUPT_DESC	= 0x18,
+	FLASH_DMA_INTERRUPT_DESC_EXT	= 0x1c,
+	FLASH_DMA_ERROR_STATUS		= 0x20,
+	FLASH_DMA_CURRENT_DESC		= 0x24,
+	FLASH_DMA_CURRENT_DESC_EXT	= 0x28,
+};
+
+static inline bool has_flash_dma(struct brcmnand_controller *ctrl)
+{
+	return ctrl->flash_dma_base;
+}
+
+static inline bool flash_dma_buf_ok(const void *buf)
+{
+	return buf && !is_vmalloc_addr(buf) &&
+		likely(IS_ALIGNED((uintptr_t)buf, 4));
+}
+
+static inline void flash_dma_writel(struct brcmnand_controller *ctrl, u8 offs,
+				    u32 val)
+{
+	brcmnand_writel(val, ctrl->flash_dma_base + offs);
+}
+
+static inline u32 flash_dma_readl(struct brcmnand_controller *ctrl, u8 offs)
+{
+	return brcmnand_readl(ctrl->flash_dma_base + offs);
+}
+
+/* Low-level operation types: command, address, write, or read */
+enum brcmnand_llop_type {
+	LL_OP_CMD,
+	LL_OP_ADDR,
+	LL_OP_WR,
+	LL_OP_RD,
+};
+
+/***********************************************************************
+ * Internal support functions
+ ***********************************************************************/
+
+static inline bool is_hamming_ecc(struct brcmnand_cfg *cfg)
+{
+	return cfg->sector_size_1k == 0 && cfg->spare_area_size == 16 &&
+		cfg->ecc_level == 15;
+}
+
+/*
+ * Returns a nand_ecclayout strucutre for the given layout/configuration.
+ * Returns NULL on failure.
+ */
+static struct nand_ecclayout *brcmnand_create_layout(int ecc_level,
+						     struct brcmnand_host *host)
+{
+	struct brcmnand_cfg *cfg = &host->hwcfg;
+	int i, j;
+	struct nand_ecclayout *layout;
+	int req;
+	int sectors;
+	int sas;
+	int idx1, idx2;
+
+	layout = devm_kzalloc(&host->pdev->dev, sizeof(*layout), GFP_KERNEL);
+	if (!layout)
+		return NULL;
+
+	sectors = cfg->page_size / (512 << cfg->sector_size_1k);
+	sas = cfg->spare_area_size << cfg->sector_size_1k;
+
+	/* Hamming */
+	if (is_hamming_ecc(cfg)) {
+		for (i = 0, idx1 = 0, idx2 = 0; i < sectors; i++) {
+			/* First sector of each page may have BBI */
+			if (i == 0) {
+				layout->oobfree[idx2].offset = i * sas + 1;
+				/* Small-page NAND use byte 6 for BBI */
+				if (cfg->page_size == 512)
+					layout->oobfree[idx2].offset--;
+				layout->oobfree[idx2].length = 5;
+			} else {
+				layout->oobfree[idx2].offset = i * sas;
+				layout->oobfree[idx2].length = 6;
+			}
+			idx2++;
+			layout->eccpos[idx1++] = i * sas + 6;
+			layout->eccpos[idx1++] = i * sas + 7;
+			layout->eccpos[idx1++] = i * sas + 8;
+			layout->oobfree[idx2].offset = i * sas + 9;
+			layout->oobfree[idx2].length = 7;
+			idx2++;
+			/* Leave zero-terminated entry for OOBFREE */
+			if (idx1 >= MTD_MAX_ECCPOS_ENTRIES_LARGE ||
+				    idx2 >= MTD_MAX_OOBFREE_ENTRIES_LARGE - 1)
+				break;
+		}
+		goto out;
+	}
+
+	/*
+	 * CONTROLLER_VERSION:
+	 *   < v5.0: ECC_REQ = ceil(BCH_T * 13/8)
+	 *  >= v5.0: ECC_REQ = ceil(BCH_T * 14/8)
+	 * But we will just be conservative.
+	 */
+	req = DIV_ROUND_UP(ecc_level * 14, 8);
+	if (req >= sas) {
+		dev_err(&host->pdev->dev,
+			"error: ECC too large for OOB (ECC bytes %d, spare sector %d)\n",
+			req, sas);
+		return NULL;
+	}
+
+	layout->eccbytes = req * sectors;
+	for (i = 0, idx1 = 0, idx2 = 0; i < sectors; i++) {
+		for (j = sas - req; j < sas && idx1 <
+				MTD_MAX_ECCPOS_ENTRIES_LARGE; j++, idx1++)
+			layout->eccpos[idx1] = i * sas + j;
+
+		/* First sector of each page may have BBI */
+		if (i == 0) {
+			if (cfg->page_size == 512 && (sas - req >= 6)) {
+				/* Small-page NAND use byte 6 for BBI */
+				layout->oobfree[idx2].offset = 0;
+				layout->oobfree[idx2].length = 5;
+				idx2++;
+				if (sas - req > 6) {
+					layout->oobfree[idx2].offset = 6;
+					layout->oobfree[idx2].length =
+						sas - req - 6;
+					idx2++;
+				}
+			} else if (sas > req + 1) {
+				layout->oobfree[idx2].offset = i * sas + 1;
+				layout->oobfree[idx2].length = sas - req - 1;
+				idx2++;
+			}
+		} else if (sas > req) {
+			layout->oobfree[idx2].offset = i * sas;
+			layout->oobfree[idx2].length = sas - req;
+			idx2++;
+		}
+		/* Leave zero-terminated entry for OOBFREE */
+		if (idx1 >= MTD_MAX_ECCPOS_ENTRIES_LARGE ||
+				idx2 >= MTD_MAX_OOBFREE_ENTRIES_LARGE - 1)
+			break;
+	}
+out:
+	/* Sum available OOB */
+	for (i = 0; i < MTD_MAX_OOBFREE_ENTRIES_LARGE; i++)
+		layout->oobavail += layout->oobfree[i].length;
+	return layout;
+}
+
+static struct nand_ecclayout *brcmstb_choose_ecc_layout(
+		struct brcmnand_host *host)
+{
+	struct nand_ecclayout *layout;
+	struct brcmnand_cfg *p = &host->hwcfg;
+	unsigned int ecc_level = p->ecc_level;
+
+	if (p->sector_size_1k)
+		ecc_level <<= 1;
+
+	layout = brcmnand_create_layout(ecc_level, host);
+	if (!layout) {
+		dev_err(&host->pdev->dev,
+				"no proper ecc_layout for this NAND cfg\n");
+		return NULL;
+	}
+
+	return layout;
+}
+
+static void brcmnand_wp(struct mtd_info *mtd, int wp)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct brcmnand_host *host = chip->priv;
+	struct brcmnand_controller *ctrl = host->ctrl;
+
+	if ((ctrl->features & BRCMNAND_HAS_WP) && wp_on == 1) {
+		static int old_wp = -1;
+
+		if (old_wp != wp) {
+			dev_dbg(ctrl->dev, "WP %s\n", wp ? "on" : "off");
+			old_wp = wp;
+		}
+		brcmnand_set_wp(ctrl, wp);
+	}
+}
+
+/* Helper functions for reading and writing OOB registers */
+static inline u8 oob_reg_read(struct brcmnand_controller *ctrl, u32 offs)
+{
+	u16 offset0, offset10, reg_offs;
+
+	offset0 = ctrl->reg_offsets[BRCMNAND_OOB_READ_BASE];
+	offset10 = ctrl->reg_offsets[BRCMNAND_OOB_READ_10_BASE];
+
+	if (offs >= ctrl->max_oob)
+		return 0x77;
+
+	if (offs >= 16 && offset10)
+		reg_offs = offset10 + ((offs - 0x10) & ~0x03);
+	else
+		reg_offs = offset0 + (offs & ~0x03);
+
+	return nand_readreg(ctrl, reg_offs) >> (24 - ((offs & 0x03) << 3));
+}
+
+static inline void oob_reg_write(struct brcmnand_controller *ctrl, u32 offs,
+				 u32 data)
+{
+	u16 offset0, offset10, reg_offs;
+
+	offset0 = ctrl->reg_offsets[BRCMNAND_OOB_WRITE_BASE];
+	offset10 = ctrl->reg_offsets[BRCMNAND_OOB_WRITE_10_BASE];
+
+	if (offs >= ctrl->max_oob)
+		return;
+
+	if (offs >= 16 && offset10)
+		reg_offs = offset10 + ((offs - 0x10) & ~0x03);
+	else
+		reg_offs = offset0 + (offs & ~0x03);
+
+	nand_writereg(ctrl, reg_offs, data);
+}
+
+/*
+ * read_oob_from_regs - read data from OOB registers
+ * @ctrl: NAND controller
+ * @i: sub-page sector index
+ * @oob: buffer to read to
+ * @sas: spare area sector size (i.e., OOB size per FLASH_CACHE)
+ * @sector_1k: 1 for 1KiB sectors, 0 for 512B, other values are illegal
+ */
+static int read_oob_from_regs(struct brcmnand_controller *ctrl, int i, u8 *oob,
+			      int sas, int sector_1k)
+{
+	int tbytes = sas << sector_1k;
+	int j;
+
+	/* Adjust OOB values for 1K sector size */
+	if (sector_1k && (i & 0x01))
+		tbytes = max(0, tbytes - (int)ctrl->max_oob);
+	tbytes = min_t(int, tbytes, ctrl->max_oob);
+
+	for (j = 0; j < tbytes; j++)
+		oob[j] = oob_reg_read(ctrl, j);
+	return tbytes;
+}
+
+/*
+ * write_oob_to_regs - write data to OOB registers
+ * @i: sub-page sector index
+ * @oob: buffer to write from
+ * @sas: spare area sector size (i.e., OOB size per FLASH_CACHE)
+ * @sector_1k: 1 for 1KiB sectors, 0 for 512B, other values are illegal
+ */
+static int write_oob_to_regs(struct brcmnand_controller *ctrl, int i,
+			     const u8 *oob, int sas, int sector_1k)
+{
+	int tbytes = sas << sector_1k;
+	int j;
+
+	/* Adjust OOB values for 1K sector size */
+	if (sector_1k && (i & 0x01))
+		tbytes = max(0, tbytes - (int)ctrl->max_oob);
+	tbytes = min_t(int, tbytes, ctrl->max_oob);
+
+	for (j = 0; j < tbytes; j += 4)
+		oob_reg_write(ctrl, j,
+				(oob[j + 0] << 24) |
+				(oob[j + 1] << 16) |
+				(oob[j + 2] <<  8) |
+				(oob[j + 3] <<  0));
+	return tbytes;
+}
+
+static irqreturn_t brcmnand_ctlrdy_irq(int irq, void *data)
+{
+	struct brcmnand_controller *ctrl = data;
+
+	/* Discard all NAND_CTLRDY interrupts during DMA */
+	if (ctrl->dma_pending)
+		return IRQ_HANDLED;
+
+	complete(&ctrl->done);
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t brcmnand_dma_irq(int irq, void *data)
+{
+	struct brcmnand_controller *ctrl = data;
+
+	complete(&ctrl->dma_done);
+
+	return IRQ_HANDLED;
+}
+
+static void brcmnand_send_cmd(struct brcmnand_host *host, int cmd)
+{
+	struct brcmnand_controller *ctrl = host->ctrl;
+	u32 intfc;
+
+	dev_dbg(ctrl->dev, "send native cmd %d addr_lo 0x%x\n", cmd,
+		brcmnand_read_reg(ctrl, BRCMNAND_CMD_ADDRESS));
+	BUG_ON(ctrl->cmd_pending != 0);
+	ctrl->cmd_pending = cmd;
+
+	intfc = brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS);
+	BUG_ON(!(intfc & INTFC_CTLR_READY));
+
+	mb(); /* flush previous writes */
+	brcmnand_write_reg(ctrl, BRCMNAND_CMD_START,
+			   cmd << brcmnand_cmd_shift(ctrl));
+}
+
+/***********************************************************************
+ * NAND MTD API: read/program/erase
+ ***********************************************************************/
+
+static void brcmnand_cmd_ctrl(struct mtd_info *mtd, int dat,
+	unsigned int ctrl)
+{
+	/* intentionally left blank */
+}
+
+static int brcmnand_waitfunc(struct mtd_info *mtd, struct nand_chip *this)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct brcmnand_host *host = chip->priv;
+	struct brcmnand_controller *ctrl = host->ctrl;
+	unsigned long timeo = msecs_to_jiffies(100);
+
+	dev_dbg(ctrl->dev, "wait on native cmd %d\n", ctrl->cmd_pending);
+	if (ctrl->cmd_pending &&
+			wait_for_completion_timeout(&ctrl->done, timeo) <= 0) {
+		u32 cmd = brcmnand_read_reg(ctrl, BRCMNAND_CMD_START)
+					>> brcmnand_cmd_shift(ctrl);
+
+		dev_err_ratelimited(ctrl->dev,
+			"timeout waiting for command %#02x\n", cmd);
+		dev_err_ratelimited(ctrl->dev, "intfc status %08x\n",
+			brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS));
+	}
+	ctrl->cmd_pending = 0;
+	return brcmnand_read_reg(ctrl, BRCMNAND_INTFC_STATUS) &
+				 INTFC_FLASH_STATUS;
+}
+
+enum {
+	LLOP_RE				= BIT(16),
+	LLOP_WE				= BIT(17),
+	LLOP_ALE			= BIT(18),
+	LLOP_CLE			= BIT(19),
+	LLOP_RETURN_IDLE		= BIT(31),
+
+	LLOP_DATA_MASK			= GENMASK(15, 0),
+};
+
+static int brcmnand_low_level_op(struct brcmnand_host *host,
+				 enum brcmnand_llop_type type, u32 data,
+				 bool last_op)
+{
+	struct mtd_info *mtd = &host->mtd;
+	struct nand_chip *chip = &host->chip;
+	struct brcmnand_controller *ctrl = host->ctrl;
+	u32 tmp;
+
+	tmp = data & LLOP_DATA_MASK;
+	switch (type) {
+	case LL_OP_CMD:
+		tmp |= LLOP_WE | LLOP_CLE;
+		break;
+	case LL_OP_ADDR:
+		/* WE | ALE */
+		tmp |= LLOP_WE | LLOP_ALE;
+		break;
+	case LL_OP_WR:
+		/* WE */
+		tmp |= LLOP_WE;
+		break;
+	case LL_OP_RD:
+		/* RE */
+		tmp |= LLOP_RE;
+		break;
+	}
+	if (last_op)
+		/* RETURN_IDLE */
+		tmp |= LLOP_RETURN_IDLE;
+
+	dev_dbg(ctrl->dev, "ll_op cmd %#x\n", tmp);
+
+	brcmnand_write_reg(ctrl, BRCMNAND_LL_OP, tmp);
+	(void)brcmnand_read_reg(ctrl, BRCMNAND_LL_OP);
+
+	brcmnand_send_cmd(host, CMD_LOW_LEVEL_OP);
+	return brcmnand_waitfunc(mtd, chip);
+}
+
+static void brcmnand_cmdfunc(struct mtd_info *mtd, unsigned command,
+			     int column, int page_addr)
+{
+	struct nand_chip *chip = mtd->priv;
+	struct brcmnand_host *host = chip->priv;
+	struct brcmnand_controller *ctrl = host->ctrl;
+	u64 addr = (u64)page_addr << chip->page_shift;
+	int native_cmd = 0;
+
+	if (command == NAND_CMD_READID || command == NAND_CMD_PARAM ||
+			command == NAND_CMD_RNDOUT)
+		addr = (u64)column;
+	/* Avoid propagating a negative, don't-care address */
+	else if (page_addr < 0)
+		addr = 0;
+
+	dev_dbg(ctrl->dev, "cmd 0x%x addr 0x%llx\n", command,
+		(unsigned long long)addr);
+
+	host->last_cmd = command;
+	host->last_byte = 0;
+	host->last_addr = addr;
+
+	switch (command) {
+	case NAND_CMD_RESET:
+		native_cmd = CMD_FLASH_RESET;
+		break;
+	case NAND_CMD_STATUS:
+		native_cmd = CMD_STATUS_READ;
+		break;
+	case NAND_CMD_READID:
+		native_cmd = CMD_DEVICE_ID_READ;
+		break;
+	case NAND_CMD_READOOB:
+		native_cmd = CMD_SPARE_AREA_READ;
+		break;
+	case NAND_CMD_ERASE1:
+		native_cmd = CMD_BLOCK_ERASE;
+		brcmnand_wp(mtd, 0);
+		break;
+	case NAND_CMD_PARAM:
+		native_cmd = CMD_PARAMETER_READ;
+		break;
+	case NAND_CMD_SET_FEATURES:
+	case NAND_CMD_GET_FEATURES:
+		brcmnand_low_level_op(host, LL_OP_CMD, command, false);
+		brcmnand_low_level_op(host, LL_OP_ADDR, column, false);
+		break;
+	case NAND_CMD_RNDOUT:
+		native_cmd = CMD_PARAMETER_CHANGE_COL;
+		addr &= ~((u64)(FC_BYTES - 1));
+		/*
+		 * HW quirk: PARAMETER_CHANGE_COL