Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2571 insertions, 0 deletions

diff --git a/drivers/memory/omap-gpmc.c b/drivers/memory/omap-gpmc.c
new file mode 100644
index 000000000..d8f2cacea
--- /dev/null
+++ b/drivers/memory/omap-gpmc.c
@@ -0,0 +1,2571 @@
+/*
+ * GPMC support functions
+ *
+ * Copyright (C) 2005-2006 Nokia Corporation
+ *
+ * Author: Juha Yrjola
+ *
+ * Copyright (C) 2009 Texas Instruments
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * 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.
+ */
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/ioport.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/consumer.h> /* GPIO descriptor enum */
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/omap-gpmc.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/platform_data/mtd-nand-omap2.h>
+
+#include <asm/mach-types.h>
+
+#define	DEVICE_NAME		"omap-gpmc"
+
+/* GPMC register offsets */
+#define GPMC_REVISION		0x00
+#define GPMC_SYSCONFIG		0x10
+#define GPMC_SYSSTATUS		0x14
+#define GPMC_IRQSTATUS		0x18
+#define GPMC_IRQENABLE		0x1c
+#define GPMC_TIMEOUT_CONTROL	0x40
+#define GPMC_ERR_ADDRESS	0x44
+#define GPMC_ERR_TYPE		0x48
+#define GPMC_CONFIG		0x50
+#define GPMC_STATUS		0x54
+#define GPMC_PREFETCH_CONFIG1	0x1e0
+#define GPMC_PREFETCH_CONFIG2	0x1e4
+#define GPMC_PREFETCH_CONTROL	0x1ec
+#define GPMC_PREFETCH_STATUS	0x1f0
+#define GPMC_ECC_CONFIG		0x1f4
+#define GPMC_ECC_CONTROL	0x1f8
+#define GPMC_ECC_SIZE_CONFIG	0x1fc
+#define GPMC_ECC1_RESULT        0x200
+#define GPMC_ECC_BCH_RESULT_0   0x240   /* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_1	0x244	/* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_2	0x248	/* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_3	0x24c	/* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_4	0x300	/* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_5	0x304	/* not available on OMAP2 */
+#define	GPMC_ECC_BCH_RESULT_6	0x308	/* not available on OMAP2 */
+
+/* GPMC ECC control settings */
+#define GPMC_ECC_CTRL_ECCCLEAR		0x100
+#define GPMC_ECC_CTRL_ECCDISABLE	0x000
+#define GPMC_ECC_CTRL_ECCREG1		0x001
+#define GPMC_ECC_CTRL_ECCREG2		0x002
+#define GPMC_ECC_CTRL_ECCREG3		0x003
+#define GPMC_ECC_CTRL_ECCREG4		0x004
+#define GPMC_ECC_CTRL_ECCREG5		0x005
+#define GPMC_ECC_CTRL_ECCREG6		0x006
+#define GPMC_ECC_CTRL_ECCREG7		0x007
+#define GPMC_ECC_CTRL_ECCREG8		0x008
+#define GPMC_ECC_CTRL_ECCREG9		0x009
+
+#define GPMC_CONFIG_LIMITEDADDRESS		BIT(1)
+
+#define GPMC_STATUS_EMPTYWRITEBUFFERSTATUS	BIT(0)
+
+#define	GPMC_CONFIG2_CSEXTRADELAY		BIT(7)
+#define	GPMC_CONFIG3_ADVEXTRADELAY		BIT(7)
+#define	GPMC_CONFIG4_OEEXTRADELAY		BIT(7)
+#define	GPMC_CONFIG4_WEEXTRADELAY		BIT(23)
+#define	GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN	BIT(6)
+#define	GPMC_CONFIG6_CYCLE2CYCLESAMECSEN	BIT(7)
+
+#define GPMC_CS0_OFFSET		0x60
+#define GPMC_CS_SIZE		0x30
+#define	GPMC_BCH_SIZE		0x10
+
+/*
+ * The first 1MB of GPMC address space is typically mapped to
+ * the internal ROM. Never allocate the first page, to
+ * facilitate bug detection; even if we didn't boot from ROM.
+ * As GPMC minimum partition size is 16MB we can only start from
+ * there.
+ */
+#define GPMC_MEM_START		0x1000000
+#define GPMC_MEM_END		0x3FFFFFFF
+
+#define GPMC_CHUNK_SHIFT	24		/* 16 MB */
+#define GPMC_SECTION_SHIFT	28		/* 128 MB */
+
+#define CS_NUM_SHIFT		24
+#define ENABLE_PREFETCH		(0x1 << 7)
+#define DMA_MPU_MODE		2
+
+#define	GPMC_REVISION_MAJOR(l)		((l >> 4) & 0xf)
+#define	GPMC_REVISION_MINOR(l)		(l & 0xf)
+
+#define	GPMC_HAS_WR_ACCESS		0x1
+#define	GPMC_HAS_WR_DATA_MUX_BUS	0x2
+#define	GPMC_HAS_MUX_AAD		0x4
+
+#define GPMC_NR_WAITPINS		4
+
+#define GPMC_CS_CONFIG1		0x00
+#define GPMC_CS_CONFIG2		0x04
+#define GPMC_CS_CONFIG3		0x08
+#define GPMC_CS_CONFIG4		0x0c
+#define GPMC_CS_CONFIG5		0x10
+#define GPMC_CS_CONFIG6		0x14
+#define GPMC_CS_CONFIG7		0x18
+#define GPMC_CS_NAND_COMMAND	0x1c
+#define GPMC_CS_NAND_ADDRESS	0x20
+#define GPMC_CS_NAND_DATA	0x24
+
+/* Control Commands */
+#define GPMC_CONFIG_RDY_BSY	0x00000001
+#define GPMC_CONFIG_DEV_SIZE	0x00000002
+#define GPMC_CONFIG_DEV_TYPE	0x00000003
+
+#define GPMC_CONFIG1_WRAPBURST_SUPP     (1 << 31)
+#define GPMC_CONFIG1_READMULTIPLE_SUPP  (1 << 30)
+#define GPMC_CONFIG1_READTYPE_ASYNC     (0 << 29)
+#define GPMC_CONFIG1_READTYPE_SYNC      (1 << 29)
+#define GPMC_CONFIG1_WRITEMULTIPLE_SUPP (1 << 28)
+#define GPMC_CONFIG1_WRITETYPE_ASYNC    (0 << 27)
+#define GPMC_CONFIG1_WRITETYPE_SYNC     (1 << 27)
+#define GPMC_CONFIG1_CLKACTIVATIONTIME(val) ((val & 3) << 25)
+/** CLKACTIVATIONTIME Max Ticks */
+#define GPMC_CONFIG1_CLKACTIVATIONTIME_MAX 2
+#define GPMC_CONFIG1_PAGE_LEN(val)      ((val & 3) << 23)
+/** ATTACHEDDEVICEPAGELENGTH Max Value */
+#define GPMC_CONFIG1_ATTACHEDDEVICEPAGELENGTH_MAX 2
+#define GPMC_CONFIG1_WAIT_READ_MON      (1 << 22)
+#define GPMC_CONFIG1_WAIT_WRITE_MON     (1 << 21)
+#define GPMC_CONFIG1_WAIT_MON_TIME(val) ((val & 3) << 18)
+/** WAITMONITORINGTIME Max Ticks */
+#define GPMC_CONFIG1_WAITMONITORINGTIME_MAX  2
+#define GPMC_CONFIG1_WAIT_PIN_SEL(val)  ((val & 3) << 16)
+#define GPMC_CONFIG1_DEVICESIZE(val)    ((val & 3) << 12)
+#define GPMC_CONFIG1_DEVICESIZE_16      GPMC_CONFIG1_DEVICESIZE(1)
+/** DEVICESIZE Max Value */
+#define GPMC_CONFIG1_DEVICESIZE_MAX     1
+#define GPMC_CONFIG1_DEVICETYPE(val)    ((val & 3) << 10)
+#define GPMC_CONFIG1_DEVICETYPE_NOR     GPMC_CONFIG1_DEVICETYPE(0)
+#define GPMC_CONFIG1_MUXTYPE(val)       ((val & 3) << 8)
+#define GPMC_CONFIG1_TIME_PARA_GRAN     (1 << 4)
+#define GPMC_CONFIG1_FCLK_DIV(val)      (val & 3)
+#define GPMC_CONFIG1_FCLK_DIV2          (GPMC_CONFIG1_FCLK_DIV(1))
+#define GPMC_CONFIG1_FCLK_DIV3          (GPMC_CONFIG1_FCLK_DIV(2))
+#define GPMC_CONFIG1_FCLK_DIV4          (GPMC_CONFIG1_FCLK_DIV(3))
+#define GPMC_CONFIG7_CSVALID		(1 << 6)
+
+#define GPMC_CONFIG7_BASEADDRESS_MASK	0x3f
+#define GPMC_CONFIG7_CSVALID_MASK	BIT(6)
+#define GPMC_CONFIG7_MASKADDRESS_OFFSET	8
+#define GPMC_CONFIG7_MASKADDRESS_MASK	(0xf << GPMC_CONFIG7_MASKADDRESS_OFFSET)
+/* All CONFIG7 bits except reserved bits */
+#define GPMC_CONFIG7_MASK		(GPMC_CONFIG7_BASEADDRESS_MASK | \
+					 GPMC_CONFIG7_CSVALID_MASK |     \
+					 GPMC_CONFIG7_MASKADDRESS_MASK)
+
+#define GPMC_DEVICETYPE_NOR		0
+#define GPMC_DEVICETYPE_NAND		2
+#define GPMC_CONFIG_WRITEPROTECT	0x00000010
+#define WR_RD_PIN_MONITORING		0x00600000
+
+/* ECC commands */
+#define GPMC_ECC_READ		0 /* Reset Hardware ECC for read */
+#define GPMC_ECC_WRITE		1 /* Reset Hardware ECC for write */
+#define GPMC_ECC_READSYN	2 /* Reset before syndrom is read back */
+
+#define	GPMC_NR_NAND_IRQS	2 /* number of NAND specific IRQs */
+
+enum gpmc_clk_domain {
+	GPMC_CD_FCLK,
+	GPMC_CD_CLK
+};
+
+struct gpmc_cs_data {
+	const char *name;
+
+#define GPMC_CS_RESERVED	(1 << 0)
+	u32 flags;
+
+	struct resource mem;
+};
+
+/* Structure to save gpmc cs context */
+struct gpmc_cs_config {
+	u32 config1;
+	u32 config2;
+	u32 config3;
+	u32 config4;
+	u32 config5;
+	u32 config6;
+	u32 config7;
+	int is_valid;
+};
+
+/*
+ * Structure to save/restore gpmc context
+ * to support core off on OMAP3
+ */
+struct omap3_gpmc_regs {
+	u32 sysconfig;
+	u32 irqenable;
+	u32 timeout_ctrl;
+	u32 config;
+	u32 prefetch_config1;
+	u32 prefetch_config2;
+	u32 prefetch_control;
+	struct gpmc_cs_config cs_context[GPMC_CS_NUM];
+};
+
+struct gpmc_device {
+	struct device *dev;
+	int irq;
+	struct irq_chip irq_chip;
+	struct gpio_chip gpio_chip;
+	int nirqs;
+};
+
+static struct irq_domain *gpmc_irq_domain;
+
+static struct resource	gpmc_mem_root;
+static struct gpmc_cs_data gpmc_cs[GPMC_CS_NUM];
+static DEFINE_SPINLOCK(gpmc_mem_lock);
+/* Define chip-selects as reserved by default until probe completes */
+static unsigned int gpmc_cs_num = GPMC_CS_NUM;
+static unsigned int gpmc_nr_waitpins;
+static resource_size_t phys_base, mem_size;
+static unsigned gpmc_capability;
+static void __iomem *gpmc_base;
+
+static struct clk *gpmc_l3_clk;
+
+static irqreturn_t gpmc_handle_irq(int irq, void *dev);
+
+static void gpmc_write_reg(int idx, u32 val)
+{
+	writel_relaxed(val, gpmc_base + idx);
+}
+
+static u32 gpmc_read_reg(int idx)
+{
+	return readl_relaxed(gpmc_base + idx);
+}
+
+void gpmc_cs_write_reg(int cs, int idx, u32 val)
+{
+	void __iomem *reg_addr;
+
+	reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
+	writel_relaxed(val, reg_addr);
+}
+
+static u32 gpmc_cs_read_reg(int cs, int idx)
+{
+	void __iomem *reg_addr;
+
+	reg_addr = gpmc_base + GPMC_CS0_OFFSET + (cs * GPMC_CS_SIZE) + idx;
+	return readl_relaxed(reg_addr);
+}
+
+/* TODO: Add support for gpmc_fck to clock framework and use it */
+static unsigned long gpmc_get_fclk_period(void)
+{
+	unsigned long rate = clk_get_rate(gpmc_l3_clk);
+
+	rate /= 1000;
+	rate = 1000000000 / rate;	/* In picoseconds */
+
+	return rate;
+}
+
+/**
+ * gpmc_get_clk_period - get period of selected clock domain in ps
+ * @cs Chip Select Region.
+ * @cd Clock Domain.
+ *
+ * GPMC_CS_CONFIG1 GPMCFCLKDIVIDER for cs has to be setup
+ * prior to calling this function with GPMC_CD_CLK.
+ */
+static unsigned long gpmc_get_clk_period(int cs, enum gpmc_clk_domain cd)
+{
+
+	unsigned long tick_ps = gpmc_get_fclk_period();
+	u32 l;
+	int div;
+
+	switch (cd) {
+	case GPMC_CD_CLK:
+		/* get current clk divider */
+		l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
+		div = (l & 0x03) + 1;
+		/* get GPMC_CLK period */
+		tick_ps *= div;
+		break;
+	case GPMC_CD_FCLK:
+		/* FALL-THROUGH */
+	default:
+		break;
+	}
+
+	return tick_ps;
+
+}
+
+static unsigned int gpmc_ns_to_clk_ticks(unsigned int time_ns, int cs,
+					 enum gpmc_clk_domain cd)
+{
+	unsigned long tick_ps;
+
+	/* Calculate in picosecs to yield more exact results */
+	tick_ps = gpmc_get_clk_period(cs, cd);
+
+	return (time_ns * 1000 + tick_ps - 1) / tick_ps;
+}
+
+static unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
+{
+	return gpmc_ns_to_clk_ticks(time_ns, /* any CS */ 0, GPMC_CD_FCLK);
+}
+
+static unsigned int gpmc_ps_to_ticks(unsigned int time_ps)
+{
+	unsigned long tick_ps;
+
+	/* Calculate in picosecs to yield more exact results */
+	tick_ps = gpmc_get_fclk_period();
+
+	return (time_ps + tick_ps - 1) / tick_ps;
+}
+
+static unsigned int gpmc_clk_ticks_to_ns(unsigned int ticks, int cs,
+					 enum gpmc_clk_domain cd)
+{
+	return ticks * gpmc_get_clk_period(cs, cd) / 1000;
+}
+
+unsigned int gpmc_ticks_to_ns(unsigned int ticks)
+{
+	return gpmc_clk_ticks_to_ns(ticks, /* any CS */ 0, GPMC_CD_FCLK);
+}
+
+static unsigned int gpmc_ticks_to_ps(unsigned int ticks)
+{
+	return ticks * gpmc_get_fclk_period();
+}
+
+static unsigned int gpmc_round_ps_to_ticks(unsigned int time_ps)
+{
+	unsigned long ticks = gpmc_ps_to_ticks(time_ps);
+
+	return ticks * gpmc_get_fclk_period();
+}
+
+static inline void gpmc_cs_modify_reg(int cs, int reg, u32 mask, bool value)
+{
+	u32 l;
+
+	l = gpmc_cs_read_reg(cs, reg);
+	if (value)
+		l |= mask;
+	else
+		l &= ~mask;
+	gpmc_cs_write_reg(cs, reg, l);
+}
+
+static void gpmc_cs_bool_timings(int cs, const struct gpmc_bool_timings *p)
+{
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG1,
+			   GPMC_CONFIG1_TIME_PARA_GRAN,
+			   p->time_para_granularity);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG2,
+			   GPMC_CONFIG2_CSEXTRADELAY, p->cs_extra_delay);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG3,
+			   GPMC_CONFIG3_ADVEXTRADELAY, p->adv_extra_delay);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
+			   GPMC_CONFIG4_OEEXTRADELAY, p->oe_extra_delay);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG4,
+			   GPMC_CONFIG4_WEEXTRADELAY, p->we_extra_delay);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
+			   GPMC_CONFIG6_CYCLE2CYCLESAMECSEN,
+			   p->cycle2cyclesamecsen);
+	gpmc_cs_modify_reg(cs, GPMC_CS_CONFIG6,
+			   GPMC_CONFIG6_CYCLE2CYCLEDIFFCSEN,
+			   p->cycle2cyclediffcsen);
+}
+
+#ifdef CONFIG_OMAP_GPMC_DEBUG
+/**
+ * get_gpmc_timing_reg - read a timing parameter and print DTS settings for it.
+ * @cs:      Chip Select Region
+ * @reg:     GPMC_CS_CONFIGn register offset.
+ * @st_bit:  Start Bit
+ * @end_bit: End Bit. Must be >= @st_bit.
+ * @ma:x     Maximum parameter value (before optional @shift).
+ *           If 0, maximum is as high as @st_bit and @end_bit allow.
+ * @name:    DTS node name, w/o "gpmc,"
+ * @cd:      Clock Domain of timing parameter.
+ * @shift:   Parameter value left shifts @shift, which is then printed instead of value.
+ * @raw:     Raw Format Option.
+ *           raw format:  gpmc,name = <value>
+ *           tick format: gpmc,name = <value> /&zwj;* x ns -- y ns; x ticks *&zwj;/
+ *           Where x ns -- y ns result in the same tick value.
+ *           When @max is exceeded, "invalid" is printed inside comment.
+ * @noval:   Parameter values equal to 0 are not printed.
+ * @return:  Specified timing parameter (after optional @shift).
+ *
+ */
+static int get_gpmc_timing_reg(
+	/* timing specifiers */
+	int cs, int reg, int st_bit, int end_bit, int max,
+	const char *name, const enum gpmc_clk_domain cd,
+	/* value transform */
+	int shift,
+	/* format specifiers */
+	bool raw, bool noval)
+{
+	u32 l;
+	int nr_bits;
+	int mask;
+	bool invalid;
+
+	l = gpmc_cs_read_reg(cs, reg);
+	nr_bits = end_bit - st_bit + 1;
+	mask = (1 << nr_bits) - 1;
+	l = (l >> st_bit) & mask;
+	if (!max)
+		max = mask;
+	invalid = l > max;
+	if (shift)
+		l = (shift << l);
+	if (noval && (l == 0))
+		return 0;
+	if (!raw) {
+		/* DTS tick format for timings in ns */
+		unsigned int time_ns;
+		unsigned int time_ns_min = 0;
+
+		if (l)
+			time_ns_min = gpmc_clk_ticks_to_ns(l - 1, cs, cd) + 1;
+		time_ns = gpmc_clk_ticks_to_ns(l, cs, cd);
+		pr_info("gpmc,%s = <%u>; /* %u ns - %u ns; %i ticks%s*/\n",
+			name, time_ns, time_ns_min, time_ns, l,
+			invalid ? "; invalid " : " ");
+	} else {
+		/* raw format */
+		pr_info("gpmc,%s = <%u>;%s\n", name, l,
+			invalid ? " /* invalid */" : "");
+	}
+
+	return l;
+}
+
+#define GPMC_PRINT_CONFIG(cs, config) \
+	pr_info("cs%i %s: 0x%08x\n", cs, #config, \
+		gpmc_cs_read_reg(cs, config))
+#define GPMC_GET_RAW(reg, st, end, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 1, 0)
+#define GPMC_GET_RAW_MAX(reg, st, end, max, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, GPMC_CD_FCLK, 0, 1, 0)
+#define GPMC_GET_RAW_BOOL(reg, st, end, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 1, 1)
+#define GPMC_GET_RAW_SHIFT_MAX(reg, st, end, shift, max, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, GPMC_CD_FCLK, (shift), 1, 1)
+#define GPMC_GET_TICKS(reg, st, end, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, GPMC_CD_FCLK, 0, 0, 0)
+#define GPMC_GET_TICKS_CD(reg, st, end, field, cd) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 0, field, (cd), 0, 0, 0)
+#define GPMC_GET_TICKS_CD_MAX(reg, st, end, max, field, cd) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), (max), field, (cd), 0, 0, 0)
+
+static void gpmc_show_regs(int cs, const char *desc)
+{
+	pr_info("gpmc cs%i %s:\n", cs, desc);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG1);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG2);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG3);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG4);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG5);
+	GPMC_PRINT_CONFIG(cs, GPMC_CS_CONFIG6);
+}
+
+/*
+ * Note that gpmc,wait-pin handing wrongly assumes bit 8 is available,
+ * see commit c9fb809.
+ */
+static void gpmc_cs_show_timings(int cs, const char *desc)
+{
+	gpmc_show_regs(cs, desc);
+
+	pr_info("gpmc cs%i access configuration:\n", cs);
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1,  4,  4, "time-para-granularity");
+	GPMC_GET_RAW(GPMC_CS_CONFIG1,  8,  9, "mux-add-data");
+	GPMC_GET_RAW_SHIFT_MAX(GPMC_CS_CONFIG1, 12, 13, 1,
+			 GPMC_CONFIG1_DEVICESIZE_MAX, "device-width");
+	GPMC_GET_RAW(GPMC_CS_CONFIG1, 16, 17, "wait-pin");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 21, 21, "wait-on-write");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 22, 22, "wait-on-read");
+	GPMC_GET_RAW_SHIFT_MAX(GPMC_CS_CONFIG1, 23, 24, 4,
+			       GPMC_CONFIG1_ATTACHEDDEVICEPAGELENGTH_MAX,
+			       "burst-length");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 27, 27, "sync-write");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 28, 28, "burst-write");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 29, 29, "gpmc,sync-read");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 30, 30, "burst-read");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG1, 31, 31, "burst-wrap");
+
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG2,  7,  7, "cs-extra-delay");
+
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG3,  7,  7, "adv-extra-delay");
+
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG4, 23, 23, "we-extra-delay");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG4,  7,  7, "oe-extra-delay");
+
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG6,  7,  7, "cycle2cycle-samecsen");
+	GPMC_GET_RAW_BOOL(GPMC_CS_CONFIG6,  6,  6, "cycle2cycle-diffcsen");
+
+	pr_info("gpmc cs%i timings configuration:\n", cs);
+	GPMC_GET_TICKS(GPMC_CS_CONFIG2,  0,  3, "cs-on-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG2,  8, 12, "cs-rd-off-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG2, 16, 20, "cs-wr-off-ns");
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG3,  0,  3, "adv-on-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG3,  8, 12, "adv-rd-off-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG3, 16, 20, "adv-wr-off-ns");
+	if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+		GPMC_GET_TICKS(GPMC_CS_CONFIG3, 4, 6, "adv-aad-mux-on-ns");
+		GPMC_GET_TICKS(GPMC_CS_CONFIG3, 24, 26,
+				"adv-aad-mux-rd-off-ns");
+		GPMC_GET_TICKS(GPMC_CS_CONFIG3, 28, 30,
+				"adv-aad-mux-wr-off-ns");
+	}
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4,  0,  3, "oe-on-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4,  8, 12, "oe-off-ns");
+	if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+		GPMC_GET_TICKS(GPMC_CS_CONFIG4,  4,  6, "oe-aad-mux-on-ns");
+		GPMC_GET_TICKS(GPMC_CS_CONFIG4, 13, 15, "oe-aad-mux-off-ns");
+	}
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4, 16, 19, "we-on-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4, 24, 28, "we-off-ns");
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG5,  0,  4, "rd-cycle-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG5,  8, 12, "wr-cycle-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG5, 16, 20, "access-ns");
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG5, 24, 27, "page-burst-access-ns");
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG6, 0, 3, "bus-turnaround-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG6, 8, 11, "cycle2cycle-delay-ns");
+
+	GPMC_GET_TICKS_CD_MAX(GPMC_CS_CONFIG1, 18, 19,
+			      GPMC_CONFIG1_WAITMONITORINGTIME_MAX,
+			      "wait-monitoring-ns", GPMC_CD_CLK);
+	GPMC_GET_TICKS_CD_MAX(GPMC_CS_CONFIG1, 25, 26,
+			      GPMC_CONFIG1_CLKACTIVATIONTIME_MAX,
+			      "clk-activation-ns", GPMC_CD_FCLK);
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG6, 16, 19, "wr-data-mux-bus-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG6, 24, 28, "wr-access-ns");
+}
+#else
+static inline void gpmc_cs_show_timings(int cs, const char *desc)
+{
+}
+#endif
+
+/**
+ * set_gpmc_timing_reg - set a single timing parameter for Chip Select Region.
+ * Caller is expected to have initialized CONFIG1 GPMCFCLKDIVIDER
+ * prior to calling this function with @cd equal to GPMC_CD_CLK.
+ *
+ * @cs:      Chip Select Region.
+ * @reg:     GPMC_CS_CONFIGn register offset.
+ * @st_bit:  Start Bit
+ * @end_bit: End Bit. Must be >= @st_bit.
+ * @max:     Maximum parameter value.
+ *           If 0, maximum is as high as @st_bit and @end_bit allow.
+ * @time:    Timing parameter in ns.
+ * @cd:      Timing parameter clock domain.
+ * @name:    Timing parameter name.
+ * @return:  0 on success, -1 on error.
+ */
+static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit, int max,
+			       int time, enum gpmc_clk_domain cd, const char *name)
+{
+	u32 l;
+	int ticks, mask, nr_bits;
+
+	if (time == 0)
+		ticks = 0;
+	else
+		ticks = gpmc_ns_to_clk_ticks(time, cs, cd);
+	nr_bits = end_bit - st_bit + 1;
+	mask = (1 << nr_bits) - 1;
+
+	if (!max)
+		max = mask;
+
+	if (ticks > max) {
+		pr_err("%s: GPMC CS%d: %s %d ns, %d ticks > %d ticks\n",
+		       __func__, cs, name, time, ticks, max);
+
+		return -1;
+	}
+
+	l = gpmc_cs_read_reg(cs, reg);
+#ifdef CONFIG_OMAP_GPMC_DEBUG
+	pr_info(
+		"GPMC CS%d: %-17s: %3d ticks, %3lu ns (was %3i ticks) %3d ns\n",
+	       cs, name, ticks, gpmc_get_clk_period(cs, cd) * ticks / 1000,
+			(l >> st_bit) & mask, time);
+#endif
+	l &= ~(mask << st_bit);
+	l |= ticks << st_bit;
+	gpmc_cs_write_reg(cs, reg, l);
+
+	return 0;
+}
+
+#define GPMC_SET_ONE_CD_MAX(reg, st, end, max, field, cd)  \
+	if (set_gpmc_timing_reg(cs, (reg), (st), (end), (max), \
+	    t->field, (cd), #field) < 0)                       \
+		return -1
+
+#define GPMC_SET_ONE(reg, st, end, field) \
+	GPMC_SET_ONE_CD_MAX(reg, st, end, 0, field, GPMC_CD_FCLK)
+
+/**
+ * gpmc_calc_waitmonitoring_divider - calculate proper GPMCFCLKDIVIDER based on WAITMONITORINGTIME
+ * WAITMONITORINGTIME will be _at least_ as long as desired, i.e.
+ * read  --> don't sample bus too early
+ * write --> data is longer on bus
+ *
+ * Formula:
+ * gpmc_clk_div + 1 = ceil(ceil(waitmonitoringtime_ns / gpmc_fclk_ns)
+ *                    / waitmonitoring_ticks)
+ * WAITMONITORINGTIME resulting in 0 or 1 tick with div = 1 are caught by
+ * div <= 0 check.
+ *
+ * @wait_monitoring: WAITMONITORINGTIME in ns.
+ * @return:          -1 on failure to scale, else proper divider > 0.
+ */
+static int gpmc_calc_waitmonitoring_divider(unsigned int wait_monitoring)
+{
+
+	int div = gpmc_ns_to_ticks(wait_monitoring);
+
+	div += GPMC_CONFIG1_WAITMONITORINGTIME_MAX - 1;
+	div /= GPMC_CONFIG1_WAITMONITORINGTIME_MAX;
+
+	if (div > 4)
+		return -1;
+	if (div <= 0)
+		div = 1;
+
+	return div;
+
+}
+
+/**
+ * gpmc_calc_divider - calculate GPMC_FCLK divider for sync_clk GPMC_CLK period.
+ * @sync_clk: GPMC_CLK period in ps.
+ * @return:   Returns at least 1 if GPMC_FCLK can be divided to GPMC_CLK.
+ *            Else, returns -1.
+ */
+int gpmc_calc_divider(unsigned int sync_clk)
+{
+	int div = gpmc_ps_to_ticks(sync_clk);
+
+	if (div > 4)
+		return -1;
+	if (div <= 0)
+		div = 1;
+
+	return div;
+}
+
+/**
+ * gpmc_cs_set_timings - program timing parameters for Chip Select Region.
+ * @cs:     Chip Select Region.
+ * @t:      GPMC timing parameters.
+ * @s:      GPMC timing settings.
+ * @return: 0 on success, -1 on error.
+ */
+int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t,
+			const struct gpmc_settings *s)
+{
+	int div;
+	u32 l;
+
+	div = gpmc_calc_divider(t->sync_clk);
+	if (div < 0)
+		return div;
+
+	/*
+	 * See if we need to change the divider for waitmonitoringtime.
+	 *
+	 * Calculate GPMCFCLKDIVIDER independent of gpmc,sync-clk-ps in DT for
+	 * pure asynchronous accesses, i.e. both read and write asynchronous.
+	 * However, only do so if WAITMONITORINGTIME is actually used, i.e.
+	 * either WAITREADMONITORING or WAITWRITEMONITORING is set.
+	 *
+	 * This statement must not change div to scale async WAITMONITORINGTIME
+	 * to protect mixed synchronous and asynchronous accesses.
+	 *
+	 * We raise an error later if WAITMONITORINGTIME does not fit.
+	 */
+	if (!s->sync_read && !s->sync_write &&
+	    (s->wait_on_read || s->wait_on_write)
+	   ) {
+
+		div = gpmc_calc_waitmonitoring_divider(t->wait_monitoring);
+		if (div < 0) {
+			pr_err("%s: waitmonitoringtime %3d ns too large for greatest gpmcfclkdivider.\n",
+			       __func__,
+			       t->wait_monitoring
+			       );
+			return -1;
+		}
+	}
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG2,  0,  3, cs_on);
+	GPMC_SET_ONE(GPMC_CS_CONFIG2,  8, 12, cs_rd_off);
+	GPMC_SET_ONE(GPMC_CS_CONFIG2, 16, 20, cs_wr_off);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG3,  0,  3, adv_on);
+	GPMC_SET_ONE(GPMC_CS_CONFIG3,  8, 12, adv_rd_off);
+	GPMC_SET_ONE(GPMC_CS_CONFIG3, 16, 20, adv_wr_off);
+	if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+		GPMC_SET_ONE(GPMC_CS_CONFIG3,  4,  6, adv_aad_mux_on);
+		GPMC_SET_ONE(GPMC_CS_CONFIG3, 24, 26, adv_aad_mux_rd_off);
+		GPMC_SET_ONE(GPMC_CS_CONFIG3, 28, 30, adv_aad_mux_wr_off);
+	}
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG4,  0,  3, oe_on);
+	GPMC_SET_ONE(GPMC_CS_CONFIG4,  8, 12, oe_off);
+	if (gpmc_capability & GPMC_HAS_MUX_AAD) {
+		GPMC_SET_ONE(GPMC_CS_CONFIG4,  4,  6, oe_aad_mux_on);
+		GPMC_SET_ONE(GPMC_CS_CONFIG4, 13, 15, oe_aad_mux_off);
+	}
+	GPMC_SET_ONE(GPMC_CS_CONFIG4, 16, 19, we_on);
+	GPMC_SET_ONE(GPMC_CS_CONFIG4, 24, 28, we_off);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG5,  0,  4, rd_cycle);
+	GPMC_SET_ONE(GPMC_CS_CONFIG5,  8, 12, wr_cycle);
+	GPMC_SET_ONE(GPMC_CS_CONFIG5, 16, 20, access);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG5, 24, 27, page_burst_access);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG6, 0, 3, bus_turnaround);
+	GPMC_SET_ONE(GPMC_CS_CONFIG6, 8, 11, cycle2cycle_delay);
+
+	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
+		GPMC_SET_ONE(GPMC_CS_CONFIG6, 16, 19, wr_data_mux_bus);
+	if (gpmc_capability & GPMC_HAS_WR_ACCESS)
+		GPMC_SET_ONE(GPMC_CS_CONFIG6, 24, 28, wr_access);
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
+	l &= ~0x03;
+	l |= (div - 1);
+	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
+
+	GPMC_SET_ONE_CD_MAX(GPMC_CS_CONFIG1, 18, 19,
+			    GPMC_CONFIG1_WAITMONITORINGTIME_MAX,
+			    wait_monitoring, GPMC_CD_CLK);
+	GPMC_SET_ONE_CD_MAX(GPMC_CS_CONFIG1, 25, 26,
+			    GPMC_CONFIG1_CLKACTIVATIONTIME_MAX,
+			    clk_activation, GPMC_CD_FCLK);
+
+#ifdef CONFIG_OMAP_GPMC_DEBUG
+	pr_info("GPMC CS%d CLK period is %lu ns (div %d)\n",
+			cs, (div * gpmc_get_fclk_period()) / 1000, div);
+#endif
+
+	gpmc_cs_bool_timings(cs, &t->bool_timings);
+	gpmc_cs_show_timings(cs, "after gpmc_cs_set_timings");
+
+	return 0;
+}
+
+static int gpmc_cs_set_memconf(int cs, u32 base, u32 size)
+{
+	u32 l;
+	u32 mask;
+
+	/*
+	 * Ensure that base address is aligned on a
+	 * boundary equal to or greater than size.
+	 */
+	if (base & (size - 1))
+		return -EINVAL;
+
+	base >>= GPMC_CHUNK_SHIFT;
+	mask = (1 << GPMC_SECTION_SHIFT) - size;
+	mask >>= GPMC_CHUNK_SHIFT;
+	mask <<= GPMC_CONFIG7_MASKADDRESS_OFFSET;
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	l &= ~GPMC_CONFIG7_MASK;
+	l |= base & GPMC_CONFIG7_BASEADDRESS_MASK;
+	l |= mask & GPMC_CONFIG7_MASKADDRESS_MASK;
+	l |= GPMC_CONFIG7_CSVALID;
+	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+
+	return 0;
+}
+
+static void gpmc_cs_enable_mem(int cs)
+{
+	u32 l;
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	l |= GPMC_CONFIG7_CSVALID;
+	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+}
+
+static void gpmc_cs_disable_mem(int cs)
+{
+	u32 l;
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	l &= ~GPMC_CONFIG7_CSVALID;
+	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG7, l);
+}
+
+static void gpmc_cs_get_memconf(int cs, u32 *base, u32 *size)
+{
+	u32 l;
+	u32 mask;
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	*base = (l & 0x3f) << GPMC_CHUNK_SHIFT;
+	mask = (l >> 8) & 0x0f;
+	*size = (1 << GPMC_SECTION_SHIFT) - (mask << GPMC_CHUNK_SHIFT);
+}
+
+static int gpmc_cs_mem_enabled(int cs)
+{
+	u32 l;
+
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	return l & GPMC_CONFIG7_CSVALID;
+}
+
+static void gpmc_cs_set_reserved(int cs, int reserved)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+	gpmc->flags |= GPMC_CS_RESERVED;
+}
+
+static bool gpmc_cs_reserved(int cs)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+	return gpmc->flags & GPMC_CS_RESERVED;
+}
+
+static void gpmc_cs_set_name(int cs, const char *name)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+	gpmc->name = name;
+}
+
+static const char *gpmc_cs_get_name(int cs)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+
+	return gpmc->name;
+}
+
+static unsigned long gpmc_mem_align(unsigned long size)
+{
+	int order;
+
+	size = (size - 1) >> (GPMC_CHUNK_SHIFT - 1);
+	order = GPMC_CHUNK_SHIFT - 1;
+	do {
+		size >>= 1;
+		order++;
+	} while (size);
+	size = 1 << order;
+	return size;
+}
+
+static int gpmc_cs_insert_mem(int cs, unsigned long base, unsigned long size)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+	struct resource *res = &gpmc->mem;
+	int r;
+
+	size = gpmc_mem_align(size);
+	spin_lock(&gpmc_mem_lock);
+	res->start = base;
+	res->end = base + size - 1;
+	r = request_resource(&gpmc_mem_root, res);
+	spin_unlock(&gpmc_mem_lock);
+
+	return r;
+}
+
+static int gpmc_cs_delete_mem(int cs)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+	struct resource *res = &gpmc->mem;
+	int r;
+
+	spin_lock(&gpmc_mem_lock);
+	r = release_resource(res);
+	res->start = 0;
+	res->end = 0;
+	spin_unlock(&gpmc_mem_lock);
+
+	return r;
+}
+
+/**
+ * gpmc_cs_remap - remaps a chip-select physical base address
+ * @cs:		chip-select to remap
+ * @base:	physical base address to re-map chip-select to
+ *
+ * Re-maps a chip-select to a new physical base address specified by
+ * "base". Returns 0 on success and appropriate negative error code
+ * on failure.
+ */
+static int gpmc_cs_remap(int cs, u32 base)
+{
+	int ret;
+	u32 old_base, size;
+
+	if (cs >= gpmc_cs_num) {
+		pr_err("%s: requested chip-select is disabled\n", __func__);
+		return -ENODEV;
+	}
+
+	/*
+	 * Make sure we ignore any device offsets from the GPMC partition
+	 * allocated for the chip select and that the new base confirms
+	 * to the GPMC 16MB minimum granularity.
+	 */ 
+	base &= ~(SZ_16M - 1);
+
+	gpmc_cs_get_memconf(cs, &old_base, &size);
+	if (base == old_base)
+		return 0;
+
+	ret = gpmc_cs_delete_mem(cs);
+	if (ret < 0)
+		return ret;
+
+	ret = gpmc_cs_insert_mem(cs, base, size);
+	if (ret < 0)
+		return ret;
+
+	ret = gpmc_cs_set_memconf(cs, base, size);
+
+	return ret;
+}
+
+int gpmc_cs_request(int cs, unsigned long size, unsigned long *base)
+{
+	struct gpmc_cs_data *gpmc = &gpmc_cs[cs];
+	struct resource *res = &gpmc->mem;
+	int r = -1;
+
+	if (cs >= gpmc_cs_num) {
+		pr_err("%s: requested chip-select is disabled\n", __func__);
+		return -ENODEV;
+	}
+	size = gpmc_mem_align(size);
+	if (size > (1 << GPMC_SECTION_SHIFT))
+		return -ENOMEM;
+
+	spin_lock(&gpmc_mem_lock);
+	if (gpmc_cs_reserved(cs)) {
+		r = -EBUSY;
+		goto out;
+	}
+	if (gpmc_cs_mem_enabled(cs))
+		r = adjust_resource(res, res->start & ~(size - 1), size);
+	if (r < 0)
+		r = allocate_resource(&gpmc_mem_root, res, size, 0, ~0,
+				      size, NULL, NULL);
+	if (r < 0)
+		goto out;
+
+	/* Disable CS while changing base address and size mask */
+	gpmc_cs_disable_mem(cs);
+
+	r = gpmc_cs_set_memconf(cs, res->start, resource_size(res));
+	if (r < 0) {
+		release_resource(res);
+		goto out;
+	}
+
+	/* Enable CS */
+	gpmc_cs_enable_mem(cs);
+	*base = res->start;
+	gpmc_cs_set_reserved(cs, 1);
+out:
+	spin_unlock(&gpmc_mem_lock);
+	return r;
+}
+EXPORT_SYMBOL(gpmc_cs_request);
+
+void gpmc_cs_free(int cs)
+{
+	struct gpmc_cs_data *gpmc;
+	struct resource *res;
+
+	spin_lock(&gpmc_mem_lock);
+	if (cs >= gpmc_cs_num || cs < 0 || !gpmc_cs_reserved(cs)) {
+		printk(KERN_ERR "Trying to free non-reserved GPMC CS%d\n", cs);
+		BUG();
+		spin_unlock(&gpmc_mem_lock);
+		return;
+	}
+	gpmc = &gpmc_cs[cs];
+	res = &gpmc->mem;
+
+	gpmc_cs_disable_mem(cs);
+	if (res->flags)
+		release_resource(res);
+	gpmc_cs_set_reserved(cs, 0);
+	spin_unlock(&gpmc_mem_lock);
+}
+EXPORT_SYMBOL(gpmc_cs_free);
+
+/**
+ * gpmc_configure - write request to configure gpmc
+ * @cmd: command type
+ * @wval: value to write
+ * @return status of the operation
+ */
+int gpmc_configure(int cmd, int wval)
+{
+	u32 regval;
+
+	switch (cmd) {
+	case GPMC_CONFIG_WP:
+		regval = gpmc_read_reg(GPMC_CONFIG);
+		if (wval)
+			regval &= ~GPMC_CONFIG_WRITEPROTECT; /* WP is ON */
+		else
+			regval |= GPMC_CONFIG_WRITEPROTECT;  /* WP is OFF */
+		gpmc_write_reg(GPMC_CONFIG, regval);
+		break;
+
+	default:
+		pr_err("%s: command not supported\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(gpmc_configure);
+
+static bool gpmc_nand_writebuffer_empty(void)
+{
+	if (gpmc_read_reg(GPMC_STATUS) & GPMC_STATUS_EMPTYWRITEBUFFERSTATUS)
+		return true;
+
+	return false;
+}
+
+static struct gpmc_nand_ops nand_ops = {
+	.nand_writebuffer_empty = gpmc_nand_writebuffer_empty,
+};
+
+/**
+ * gpmc_omap_get_nand_ops - Get the GPMC NAND interface
+ * @regs: the GPMC NAND register map exclusive for NAND use.
+ * @cs: GPMC chip select number on which the NAND sits. The
+ *      register map returned will be specific to this chip select.
+ *
+ * Returns NULL on error e.g. invalid cs.
+ */
+struct gpmc_nand_ops *gpmc_omap_get_nand_ops(struct gpmc_nand_regs *reg, int cs)
+{
+	int i;
+
+	if (cs >= gpmc_cs_num)
+		return NULL;
+
+	reg->gpmc_nand_command = gpmc_base + GPMC_CS0_OFFSET +
+				GPMC_CS_NAND_COMMAND + GPMC_CS_SIZE * cs;
+	reg->gpmc_nand_address = gpmc_base + GPMC_CS0_OFFSET +
+				GPMC_CS_NAND_ADDRESS + GPMC_CS_SIZE * cs;
+	reg->gpmc_nand_data = gpmc_base + GPMC_CS0_OFFSET +
+				GPMC_CS_NAND_DATA + GPMC_CS_SIZE * cs;
+	reg->gpmc_prefetch_config1 = gpmc_base + GPMC_PREFETCH_CONFIG1;
+	reg->gpmc_prefetch_config2 = gpmc_base + GPMC_PREFETCH_CONFIG2;
+	reg->gpmc_prefetch_control = gpmc_base + GPMC_PREFETCH_CONTROL;
+	reg->gpmc_prefetch_status = gpmc_base + GPMC_PREFETCH_STATUS;
+	reg->gpmc_ecc_config = gpmc_base + GPMC_ECC_CONFIG;
+	reg->gpmc_ecc_control = gpmc_base + GPMC_ECC_CONTROL;
+	reg->gpmc_ecc_size_config = gpmc_base + GPMC_ECC_SIZE_CONFIG;
+	reg->gpmc_ecc1_result = gpmc_base + GPMC_ECC1_RESULT;
+
+	for (i = 0; i < GPMC_BCH_NUM_REMAINDER; i++) {
+		reg->gpmc_bch_result0[i] = gpmc_base + GPMC_ECC_BCH_RESULT_0 +
+					   GPMC_BCH_SIZE * i;
+		reg->gpmc_bch_result1[i] = gpmc_base + GPMC_ECC_BCH_RESULT_1 +
+					   GPMC_BCH_SIZE * i;
+		reg->gpmc_bch_result2[i] = gpmc_base + GPMC_ECC_BCH_RESULT_2 +
+					   GPMC_BCH_SIZE * i;
+		reg->gpmc_bch_result3[i] = gpmc_base + GPMC_ECC_BCH_RESULT_3 +
+					   GPMC_BCH_SIZE * i;
+		reg->gpmc_bch_result4[i] = gpmc_base + GPMC_ECC_BCH_RESULT_4 +
+					   i * GPMC_BCH_SIZE;
+		reg->gpmc_bch_result5[i] = gpmc_base + GPMC_ECC_BCH_RESULT_5 +
+					   i * GPMC_BCH_SIZE;
+		reg->gpmc_bch_result6[i] = gpmc_base + GPMC_ECC_BCH_RESULT_6 +
+					   i * GPMC_BCH_SIZE;
+	}
+
+	return &nand_ops;
+}
+EXPORT_SYMBOL_GPL(gpmc_omap_get_nand_ops);
+
+static void gpmc_omap_onenand_calc_sync_timings(struct gpmc_timings *t,
+						struct gpmc_settings *s,
+						int freq, int latency)
+{
+	struct gpmc_device_timings dev_t;
+	const int t_cer  = 15;
+	const int t_avdp = 12;
+	const int t_cez  = 20; /* max of t_cez, t_oez */
+	const int t_wpl  = 40;
+	const int t_wph  = 30;
+	int min_gpmc_clk_period, t_ces, t_avds, t_avdh, t_ach, t_aavdh, t_rdyo;
+
+	switch (freq) {
+	case 104:
+		min_gpmc_clk_period = 9600; /* 104 MHz */
+		t_ces   = 3;
+		t_avds  = 4;
+		t_avdh  = 2;
+		t_ach   = 3;
+		t_aavdh = 6;
+		t_rdyo  = 6;
+		break;
+	case 83:
+		min_gpmc_clk_period = 12000; /* 83 MHz */
+		t_ces   = 5;
+		t_avds  = 4;
+		t_avdh  = 2;
+		t_ach   = 6;
+		t_aavdh = 6;
+		t_rdyo  = 9;
+		break;
+	case 66:
+		min_gpmc_clk_period = 15000; /* 66 MHz */
+		t_ces   = 6;
+		t_avds  = 5;
+		t_avdh  = 2;
+		t_ach   = 6;
+		t_aavdh = 6;
+		t_rdyo  = 11;
+		break;
+	default:
+		min_gpmc_clk_period = 18500; /* 54 MHz */
+		t_ces   = 7;
+		t_avds  = 7;
+		t_avdh  = 7;
+		t_ach   = 9;
+		t_aavdh = 7;
+		t_rdyo  = 15;
+		break;
+	}
+
+	/* Set synchronous read timings */
+	memset(&dev_t, 0, sizeof(dev_t));
+
+	if (!s->sync_write) {
+		dev_t.t_avdp_w = max(t_avdp, t_cer) * 1000;
+		dev_t.t_wpl = t_wpl * 1000;
+		dev_t.t_wph = t_wph * 1000;
+		dev_t.t_aavdh = t_aavdh * 1000;
+	}
+	dev_t.ce_xdelay = true;
+	dev_t.avd_xdelay = true;
+	dev_t.oe_xdelay = true;
+	dev_t.we_xdelay = true;
+	dev_t.clk = min_gpmc_clk_period;
+	dev_t.t_bacc = dev_t.clk;
+	dev_t.t_ces = t_ces * 1000;
+	dev_t.t_avds = t_avds * 1000;
+	dev_t.t_avdh = t_avdh * 1000;
+	dev_t.t_ach = t_ach * 1000;
+	dev_t.cyc_iaa = (latency + 1);
+	dev_t.t_cez_r = t_cez * 1000;
+	dev_t.t_cez_w = dev_t.t_cez_r;
+	dev_t.cyc_aavdh_oe = 1;
+	dev_t.t_rdyo = t_rdyo * 1000 + min_gpmc_clk_period;
+
+	gpmc_calc_timings(t, s, &dev_t);
+}
+
+int gpmc_omap_onenand_set_timings(struct device *dev, int cs, int freq,
+				  int latency,
+				  struct gpmc_onenand_info *info)
+{
+	int ret;
+	struct gpmc_timings gpmc_t;
+	struct gpmc_settings gpmc_s;
+
+	gpmc_read_settings_dt(dev->of_node, &gpmc_s);
+
+	info->sync_read = gpmc_s.sync_read;
+	info->sync_write = gpmc_s.sync_write;
+	info->burst_len = gpmc_s.burst_len;
+
+	if (!gpmc_s.sync_read && !gpmc_s.sync_write)
+		return 0;
+
+	gpmc_omap_onenand_calc_sync_timings(&gpmc_t, &gpmc_s, freq, latency);
+
+	ret = gpmc_cs_program_settings(cs, &gpmc_s);
+	if (ret < 0)
+		return ret;
+
+	return gpmc_cs_set_timings(cs, &gpmc_t, &gpmc_s);
+}
+EXPORT_SYMBOL_GPL(gpmc_omap_onenand_set_timings);
+
+int gpmc_get_client_irq(unsigned irq_config)
+{
+	if (!gpmc_irq_domain) {
+		pr_warn("%s called before GPMC IRQ domain available\n",
+			__func__);
+		return 0;
+	}
+
+	/* we restrict this to NAND IRQs only */
+	if (irq_config >= GPMC_NR_NAND_IRQS)
+		return 0;
+
+	return irq_create_mapping(gpmc_irq_domain, irq_config);
+}
+
+static int gpmc_irq_endis(unsigned long hwirq, bool endis)
+{
+	u32 regval;
+
+	/* bits GPMC_NR_NAND_IRQS to 8 are reserved */
+	if (hwirq >= GPMC_NR_NAND_IRQS)
+		hwirq += 8 - GPMC_NR_NAND_IRQS;
+
+	regval = gpmc_read_reg(GPMC_IRQENABLE);
+	if (endis)
+		regval |= BIT(hwirq);
+	else
+		regval &= ~BIT(hwirq);
+	gpmc_write_reg(GPMC_IRQENABLE, regval);
+
+	return 0;
+}
+
+static void gpmc_irq_disable(struct irq_data *p)
+{
+	gpmc_irq_endis(p->hwirq, false);
+}
+
+static void gpmc_irq_enable(struct irq_data *p)
+{
+	gpmc_irq_endis(p->hwirq, true);
+}
+
+static void gpmc_irq_mask(struct irq_data *d)
+{
+	gpmc_irq_endis(d->hwirq, false);
+}
+
+static void gpmc_irq_unmask(struct irq_data *d)
+{
+	gpmc_irq_endis(d->hwirq, true);
+}
+
+static void gpmc_irq_edge_config(unsigned long hwirq, bool rising_edge)
+{
+	u32 regval;
+
+	/* NAND IRQs polarity is not configurable */
+	if (hwirq < GPMC_NR_NAND_IRQS)
+		return;
+
+	/* WAITPIN starts at BIT 8 */
+	hwirq += 8 - GPMC_NR_NAND_IRQS;
+
+	regval = gpmc_read_reg(GPMC_CONFIG);
+	if (rising_edge)
+		regval &= ~BIT(hwirq);
+	else
+		regval |= BIT(hwirq);
+
+	gpmc_write_reg(GPMC_CONFIG, regval);
+}
+
+static void gpmc_irq_ack(struct irq_data *d)
+{
+	unsigned int hwirq = d->hwirq;
+
+	/* skip reserved bits */
+	if (hwirq >= GPMC_NR_NAND_IRQS)
+		hwirq += 8 - GPMC_NR_NAND_IRQS;
+
+	/* Setting bit to 1 clears (or Acks) the interrupt */
+	gpmc_write_reg(GPMC_IRQSTATUS, BIT(hwirq));
+}
+
+static int gpmc_irq_set_type(struct irq_data *d, unsigned int trigger)
+{
+	/* can't set type for NAND IRQs */
+	if (d->hwirq < GPMC_NR_NAND_IRQS)
+		return -EINVAL;
+
+	/* We can support either rising or falling edge at a time */
+	if (trigger == IRQ_TYPE_EDGE_FALLING)
+		gpmc_irq_edge_config(d->hwirq, false);
+	else if (trigger == IRQ_TYPE_EDGE_RISING)
+		gpmc_irq_edge_config(d->hwirq, true);
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+static int gpmc_irq_map(struct irq_domain *d, unsigned int virq,
+			irq_hw_number_t hw)
+{
+	struct gpmc_device *gpmc = d->host_data;
+
+	irq_set_chip_data(virq, gpmc);
+	if (hw < GPMC_NR_NAND_IRQS) {
+		irq_modify_status(virq, IRQ_NOREQUEST, IRQ_NOAUTOEN);
+		irq_set_chip_and_handler(virq, &gpmc->irq_chip,
+					 handle_simple_irq);
+	} else {
+		irq_set_chip_and_handler(virq, &gpmc->irq_chip,
+					 handle_edge_irq);
+	}
+
+	return 0;
+}
+
+static const struct irq_domain_ops gpmc_irq_domain_ops = {
+	.map    = gpmc_irq_map,
+	.xlate  = irq_domain_xlate_twocell,
+};
+
+static irqreturn_t gpmc_handle_irq(int irq, void *data)
+{
+	int hwirq, virq;
+	u32 regval, regvalx;
+	struct gpmc_device *gpmc = data;
+
+	regval = gpmc_read_reg(GPMC_IRQSTATUS);
+	regvalx = regval;
+
+	if (!regval)
+		return IRQ_NONE;
+
+	for (hwirq = 0; hwirq < gpmc->nirqs; hwirq++) {
+		/* skip reserved status bits */
+		if (hwirq == GPMC_NR_NAND_IRQS)
+			regvalx >>= 8 - GPMC_NR_NAND_IRQS;
+
+		if (regvalx & BIT(hwirq)) {
+			virq = irq_find_mapping(gpmc_irq_domain, hwirq);
+			if (!virq) {
+				dev_warn(gpmc->dev,
+					 "spurious irq detected hwirq %d, virq %d\n",
+					 hwirq, virq);
+			}
+
+			generic_handle_irq(virq);
+		}
+	}
+
+	gpmc_write_reg(GPMC_IRQSTATUS, regval);
+
+	return IRQ_HANDLED;
+}
+
+static int gpmc_setup_irq(struct gpmc_device *gpmc)
+{
+	u32 regval;
+	int rc;
+
+	/* Disable interrupts */
+	gpmc_write_reg(GPMC_IRQENABLE, 0);
+
+	/* clear interrupts */
+	regval = gpmc_read_reg(GPMC_IRQSTATUS);
+	gpmc_write_reg(GPMC_IRQSTATUS, regval);
+
+	gpmc->irq_chip.name = "gpmc";
+	gpmc->irq_chip.irq_enable = gpmc_irq_enable;
+	gpmc->irq_chip.irq_disable = gpmc_irq_disable;
+	gpmc->irq_chip.irq_ack = gpmc_irq_ack;
+	gpmc->irq_chip.irq_mask = gpmc_irq_mask;
+	gpmc->irq_chip.irq_unmask = gpmc_irq_unmask;
+	gpmc->irq_chip.irq_set_type = gpmc_irq_set_type;
+
+	gpmc_irq_domain = irq_domain_add_linear(gpmc->dev->of_node,
+						gpmc->nirqs,
+						&gpmc_irq_domain_ops,
+						gpmc);
+	if (!gpmc_irq_domain) {
+		dev_err(gpmc->dev, "IRQ domain add failed\n");
+		return -ENODEV;
+	}
+
+	rc = request_irq(gpmc->irq, gpmc_handle_irq, 0, "gpmc", gpmc);
+	if (rc) {
+		dev_err(gpmc->dev, "failed to request irq %d: %d\n",
+			gpmc->irq, rc);
+		irq_domain_remove(gpmc_irq_domain);
+		gpmc_irq_domain = NULL;
+	}
+
+	return rc;
+}
+
+static int gpmc_free_irq(struct gpmc_device *gpmc)
+{
+	int hwirq;
+
+	free_irq(gpmc->irq, gpmc);
+
+	for (hwirq = 0; hwirq < gpmc->nirqs; hwirq++)
+		irq_dispose_mapping(irq_find_mapping(gpmc_irq_domain, hwirq));
+
+	irq_domain_remove(gpmc_irq_domain);
+	gpmc_irq_domain = NULL;
+
+	return 0;
+}
+
+static void gpmc_mem_exit(void)
+{
+	int cs;
+
+	for (cs = 0; cs < gpmc_cs_num; cs++) {
+		if (!gpmc_cs_mem_enabled(cs))
+			continue;
+		gpmc_cs_delete_mem(cs);
+	}
+
+}
+
+static void gpmc_mem_init(void)
+{
+	int cs;
+
+	gpmc_mem_root.start = GPMC_MEM_START;
+	gpmc_mem_root.end = GPMC_MEM_END;
+
+	/* Reserve all regions that has been set up by bootloader */
+	for (cs = 0; cs < gpmc_cs_num; cs++) {
+		u32 base, size;
+
+		if (!gpmc_cs_mem_enabled(cs))
+			continue;
+		gpmc_cs_get_memconf(cs, &base, &size);
+		if (gpmc_cs_insert_mem(cs, base, size)) {
+			pr_warn("%s: disabling cs %d mapped at 0x%x-0x%x\n",
+				__func__, cs, base, base + size);
+			gpmc_cs_disable_mem(cs);
+		}
+	}
+}
+
+static u32 gpmc_round_ps_to_sync_clk(u32 time_ps, u32 sync_clk)
+{
+	u32 temp;
+	int div;
+
+	div = gpmc_calc_divider(sync_clk);
+	temp = gpmc_ps_to_ticks(time_ps);
+	temp = (temp + div - 1) / div;
+	return gpmc_ticks_to_ps(temp * div);
+}
+
+/* XXX: can the cycles be avoided ? */
+static int gpmc_calc_sync_read_timings(struct gpmc_timings *gpmc_t,
+				       struct gpmc_device_timings *dev_t,
+				       bool mux)
+{
+	u32 temp;
+
+	/* adv_rd_off */
+	temp = dev_t->t_avdp_r;
+	/* XXX: mux check required ? */
+	if (mux) {
+		/* XXX: t_avdp not to be required for sync, only added for tusb
+		 * this indirectly necessitates requirement of t_avdp_r and
+		 * t_avdp_w instead of having a single t_avdp
+		 */
+		temp = max_t(u32, temp,	gpmc_t->clk_activation + dev_t->t_avdh);
+		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+	}
+	gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);
+
+	/* oe_on */
+	temp = dev_t->t_oeasu; /* XXX: remove this ? */
+	if (mux) {
+		temp = max_t(u32, temp,	gpmc_t->clk_activation + dev_t->t_ach);
+		temp = max_t(u32, temp, gpmc_t->adv_rd_off +
+				gpmc_ticks_to_ps(dev_t->cyc_aavdh_oe));
+	}
+	gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);
+
+	/* access */
+	/* XXX: any scope for improvement ?, by combining oe_on
+	 * and clk_activation, need to check whether
+	 * access = clk_activation + round to sync clk ?
+	 */
+	temp = max_t(u32, dev_t->t_iaa,	dev_t->cyc_iaa * gpmc_t->sync_clk);
+	temp += gpmc_t->clk_activation;
+	if (dev_t->cyc_oe)
+		temp = max_t(u32, temp, gpmc_t->oe_on +
+				gpmc_ticks_to_ps(dev_t->cyc_oe));
+	gpmc_t->access = gpmc_round_ps_to_ticks(temp);
+
+	gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
+	gpmc_t->cs_rd_off = gpmc_t->oe_off;
+
+	/* rd_cycle */
+	temp = max_t(u32, dev_t->t_cez_r, dev_t->t_oez);
+	temp = gpmc_round_ps_to_sync_clk(temp, gpmc_t->sync_clk) +
+							gpmc_t->access;
+	/* XXX: barter t_ce_rdyz with t_cez_r ? */
+	if (dev_t->t_ce_rdyz)
+		temp = max_t(u32, temp,	gpmc_t->cs_rd_off + dev_t->t_ce_rdyz);
+	gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);
+
+	return 0;
+}
+
+static int gpmc_calc_sync_write_timings(struct gpmc_timings *gpmc_t,
+					struct gpmc_device_timings *dev_t,
+					bool mux)
+{
+	u32 temp;
+
+	/* adv_wr_off */
+	temp = dev_t->t_avdp_w;
+	if (mux) {
+		temp = max_t(u32, temp,
+			gpmc_t->clk_activation + dev_t->t_avdh);
+		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+	}
+	gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);
+
+	/* wr_data_mux_bus */
+	temp = max_t(u32, dev_t->t_weasu,
+			gpmc_t->clk_activation + dev_t->t_rdyo);
+	/* XXX: shouldn't mux be kept as a whole for wr_data_mux_bus ?,
+	 * and in that case remember to handle we_on properly
+	 */
+	if (mux) {
+		temp = max_t(u32, temp,
+			gpmc_t->adv_wr_off + dev_t->t_aavdh);
+		temp = max_t(u32, temp, gpmc_t->adv_wr_off +
+				gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
+	}
+	gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);
+
+	/* we_on */
+	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
+		gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
+	else
+		gpmc_t->we_on = gpmc_t->wr_data_mux_bus;
+
+	/* wr_access */
+	/* XXX: gpmc_capability check reqd ? , even if not, will not harm */
+	gpmc_t->wr_access = gpmc_t->access;
+
+	/* we_off */
+	temp = gpmc_t->we_on + dev_t->t_wpl;
+	temp = max_t(u32, temp,
+			gpmc_t->wr_access + gpmc_ticks_to_ps(1));
+	temp = max_t(u32, temp,
+		gpmc_t->we_on + gpmc_ticks_to_ps(dev_t->cyc_wpl));
+	gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);
+
+	gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
+							dev_t->t_wph);
+
+	/* wr_cycle */
+	temp = gpmc_round_ps_to_sync_clk(dev_t->t_cez_w, gpmc_t->sync_clk);
+	temp += gpmc_t->wr_access;
+	/* XXX: barter t_ce_rdyz with t_cez_w ? */
+	if (dev_t->t_ce_rdyz)
+		temp = max_t(u32, temp,
+				 gpmc_t->cs_wr_off + dev_t->t_ce_rdyz);
+	gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);
+
+	return 0;
+}
+
+static int gpmc_calc_async_read_timings(struct gpmc_timings *gpmc_t,
+					struct gpmc_device_timings *dev_t,
+					bool mux)
+{
+	u32 temp;
+
+	/* adv_rd_off */
+	temp = dev_t->t_avdp_r;
+	if (mux)
+		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+	gpmc_t->adv_rd_off = gpmc_round_ps_to_ticks(temp);
+
+	/* oe_on */
+	temp = dev_t->t_oeasu;
+	if (mux)
+		temp = max_t(u32, temp,
+			gpmc_t->adv_rd_off + dev_t->t_aavdh);
+	gpmc_t->oe_on = gpmc_round_ps_to_ticks(temp);
+
+	/* access */
+	temp = max_t(u32, dev_t->t_iaa, /* XXX: remove t_iaa in async ? */
+				gpmc_t->oe_on + dev_t->t_oe);
+	temp = max_t(u32, temp,
+				gpmc_t->cs_on + dev_t->t_ce);
+	temp = max_t(u32, temp,
+				gpmc_t->adv_on + dev_t->t_aa);
+	gpmc_t->access = gpmc_round_ps_to_ticks(temp);
+
+	gpmc_t->oe_off = gpmc_t->access + gpmc_ticks_to_ps(1);
+	gpmc_t->cs_rd_off = gpmc_t->oe_off;
+
+	/* rd_cycle */
+	temp = max_t(u32, dev_t->t_rd_cycle,
+			gpmc_t->cs_rd_off + dev_t->t_cez_r);
+	temp = max_t(u32, temp, gpmc_t->oe_off + dev_t->t_oez);
+	gpmc_t->rd_cycle = gpmc_round_ps_to_ticks(temp);
+
+	return 0;
+}
+
+static int gpmc_calc_async_write_timings(struct gpmc_timings *gpmc_t,
+					 struct gpmc_device_timings *dev_t,
+					 bool mux)
+{
+	u32 temp;
+
+	/* adv_wr_off */
+	temp = dev_t->t_avdp_w;
+	if (mux)
+		temp = max_t(u32, gpmc_t->adv_on + gpmc_ticks_to_ps(1), temp);
+	gpmc_t->adv_wr_off = gpmc_round_ps_to_ticks(temp);
+
+	/* wr_data_mux_bus */
+	temp = dev_t->t_weasu;
+	if (mux) {
+		temp = max_t(u32, temp,	gpmc_t->adv_wr_off + dev_t->t_aavdh);
+		temp = max_t(u32, temp, gpmc_t->adv_wr_off +
+				gpmc_ticks_to_ps(dev_t->cyc_aavdh_we));
+	}
+	gpmc_t->wr_data_mux_bus = gpmc_round_ps_to_ticks(temp);
+
+	/* we_on */
+	if (gpmc_capability & GPMC_HAS_WR_DATA_MUX_BUS)
+		gpmc_t->we_on = gpmc_round_ps_to_ticks(dev_t->t_weasu);
+	else
+		gpmc_t->we_on = gpmc_t->wr_data_mux_bus;
+
+	/* we_off */
+	temp = gpmc_t->we_on + dev_t->t_wpl;
+	gpmc_t->we_off = gpmc_round_ps_to_ticks(temp);
+
+	gpmc_t->cs_wr_off = gpmc_round_ps_to_ticks(gpmc_t->we_off +
+							dev_t->t_wph);
+
+	/* wr_cycle */
+	temp = max_t(u32, dev_t->t_wr_cycle,
+				gpmc_t->cs_wr_off + dev_t->t_cez_w);
+	gpmc_t->wr_cycle = gpmc_round_ps_to_ticks(temp);
+
+	return 0;
+}
+
+static int gpmc_calc_sync_common_timings(struct gpmc_timings *gpmc_t,
+			struct gpmc_device_timings *dev_t)
+{
+	u32 temp;
+
+	gpmc_t->sync_clk = gpmc_calc_divider(dev_t->clk) *
+						gpmc_get_fclk_period();
+
+	gpmc_t->page_burst_access = gpmc_round_ps_to_sync_clk(
+					dev_t->t_bacc,
+					gpmc_t->sync_clk);
+
+	temp = max_t(u32, dev_t->t_ces, dev_t->t_avds);
+	gpmc_t->clk_activation = gpmc_round_ps_to_ticks(temp);
+
+	if (gpmc_calc_divider(gpmc_t->sync_clk) != 1)
+		return 0;
+
+	if (dev_t->ce_xdelay)
+		gpmc_t->bool_timings.cs_extra_delay = true;
+	if (dev_t->avd_xdelay)
+		gpmc_t->bool_timings.adv_extra_delay = true;
+	if (dev_t->oe_xdelay)
+		gpmc_t->bool_timings.oe_extra_delay = true;
+	if (dev_t->we_xdelay)
+		gpmc_t->bool_timings.we_extra_delay = true;
+
+	return 0;
+}
+
+static int gpmc_calc_common_timings(struct gpmc_timings *gpmc_t,
+				    struct gpmc_device_timings *dev_t,
+				    bool sync)
+{
+	u32 temp;
+
+	/* cs_on */
+	gpmc_t->cs_on = gpmc_round_ps_to_ticks(dev_t->t_ceasu);
+
+	/* adv_on */
+	temp = dev_t->t_avdasu;
+	if (dev_t->t_ce_avd)
+		temp = max_t(u32, temp,
+				gpmc_t->cs_on + dev_t->t_ce_avd);
+	gpmc_t->adv_on = gpmc_round_ps_to_ticks(temp);
+
+	if (sync)
+		gpmc_calc_sync_common_timings(gpmc_t, dev_t);
+
+	return 0;
+}
+
+/* TODO: remove this function once all peripherals are confirmed to
+ * work with generic timing. Simultaneously gpmc_cs_set_timings()
+ * has to be modified to handle timings in ps instead of ns
+*/
+static void gpmc_convert_ps_to_ns(struct gpmc_timings *t)
+{
+	t->cs_on /= 1000;
+	t->cs_rd_off /= 1000;
+	t->cs_wr_off /= 1000;
+	t->adv_on /= 1000;
+	t->adv_rd_off /= 1000;
+	t->adv_wr_off /= 1000;
+	t->we_on /= 1000;
+	t->we_off /= 1000;
+	t->oe_on /= 1000;
+	t->oe_off /= 1000;
+	t->page_burst_access /= 1000;
+	t->access /= 1000;
+	t->rd_cycle /= 1000;
+	t->wr_cycle /= 1000;
+	t->bus_turnaround /= 1000;
+	t->cycle2cycle_delay /= 1000;
+	t->wait_monitoring /= 1000;
+	t->clk_activation /= 1000;
+	t->wr_access /= 1000;
+	t->wr_data_mux_bus /= 1000;
+}
+
+int gpmc_calc_timings(struct gpmc_timings *gpmc_t,
+		      struct gpmc_settings *gpmc_s,
+		      struct gpmc_device_timings *dev_t)
+{
+	bool mux = false, sync = false;
+
+	if (gpmc_s) {
+		mux = gpmc_s->mux_add_data ? true : false;
+		sync = (gpmc_s->sync_read || gpmc_s->sync_write);
+	}
+
+	memset(gpmc_t, 0, sizeof(*gpmc_t));
+
+	gpmc_calc_common_timings(gpmc_t, dev_t, sync);
+
+	if (gpmc_s && gpmc_s->sync_read)
+		gpmc_calc_sync_read_timings(gpmc_t, dev_t, mux);
+	else
+		gpmc_calc_async_read_timings(gpmc_t, dev_t, mux);
+
+	if (gpmc_s && gpmc_s->sync_write)
+		gpmc_calc_sync_write_timings(gpmc_t, dev_t, mux);
+	else
+		gpmc_calc_async_write_timings(gpmc_t, dev_t, mux);
+
+	/* TODO: remove, see function definition */
+	gpmc_convert_ps_to_ns(gpmc_t);
+
+	return 0;
+}
+
+/**
+ * gpmc_cs_program_settings - programs non-timing related settings
+ * @cs:		GPMC chip-select to program
+ * @p:		pointer to GPMC settings structure
+ *
+ * Programs non-timing related settings for a GPMC chip-select, such as
+ * bus-width, burst configuration, etc. Function should be called once
+ * for each chip-select that is being used and must be called before
+ * calling gpmc_cs_set_timings() as timing parameters in the CONFIG1
+ * register will be initialised to zero by this function. Returns 0 on
+ * success and appropriate negative error code on failure.
+ */
+int gpmc_cs_program_settings(int cs, struct gpmc_settings *p)
+{
+	u32 config1;
+
+	if ((!p->device_width) || (p->device_width > GPMC_DEVWIDTH_16BIT)) {
+		pr_err("%s: invalid width %d!", __func__, p->device_width);
+		return -EINVAL;
+	}
+
+	/* Address-data multiplexing not supported for NAND devices */
+	if (p->device_nand && p->mux_add_data) {
+		pr_err("%s: invalid configuration!\n", __func__);
+		return -EINVAL;
+	}
+
+	if ((p->mux_add_data > GPMC_MUX_AD) ||
+	    ((p->mux_add_data == GPMC_MUX_AAD) &&
+	     !(gpmc_capability & GPMC_HAS_MUX_AAD))) {
+		pr_err("%s: invalid multiplex configuration!\n", __func__);
+		return -EINVAL;
+	}
+
+	/* Page/burst mode supports lengths of 4, 8 and 16 bytes */
+	if (p->burst_read || p->burst_write) {
+		switch (p->burst_len) {
+		case GPMC_BURST_4:
+		case GPMC_BURST_8:
+		case GPMC_BURST_16:
+			break;
+		default:
+			pr_err("%s: invalid page/burst-length (%d)\n",
+			       __func__, p->burst_len);
+			return -EINVAL;
+		}
+	}
+
+	if (p->wait_pin > gpmc_nr_waitpins) {
+		pr_err("%s: invalid wait-pin (%d)\n", __func__, p->wait_pin);
+		return -EINVAL;
+	}
+
+	config1 = GPMC_CONFIG1_DEVICESIZE((p->device_width - 1));
+
+	if (p->sync_read)
+		config1 |= GPMC_CONFIG1_READTYPE_SYNC;
+	if (p->sync_write)
+		config1 |= GPMC_CONFIG1_WRITETYPE_SYNC;
+	if (p->wait_on_read)
+		config1 |= GPMC_CONFIG1_WAIT_READ_MON;
+	if (p->wait_on_write)
+		config1 |= GPMC_CONFIG1_WAIT_WRITE_MON;
+	if (p->wait_on_read || p->wait_on_write)
+		config1 |= GPMC_CONFIG1_WAIT_PIN_SEL(p->wait_pin);
+	if (p->device_nand)
+		config1	|= GPMC_CONFIG1_DEVICETYPE(GPMC_DEVICETYPE_NAND);
+	if (p->mux_add_data)
+		config1	|= GPMC_CONFIG1_MUXTYPE(p->mux_add_data);
+	if (p->burst_read)
+		config1 |= GPMC_CONFIG1_READMULTIPLE_SUPP;
+	if (p->burst_write)
+		config1 |= GPMC_CONFIG1_WRITEMULTIPLE_SUPP;
+	if (p->burst_read || p->burst_write) {
+		config1 |= GPMC_CONFIG1_PAGE_LEN(p->burst_len >> 3);
+		config1 |= p->burst_wrap ? GPMC_CONFIG1_WRAPBURST_SUPP : 0;
+	}
+
+	gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, config1);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpmc_dt_ids[] = {
+	{ .compatible = "ti,omap2420-gpmc" },
+	{ .compatible = "ti,omap2430-gpmc" },
+	{ .compatible = "ti,omap3430-gpmc" },	/* omap3430 & omap3630 */
+	{ .compatible = "ti,omap4430-gpmc" },	/* omap4430 & omap4460 & omap543x */
+	{ .compatible = "ti,am3352-gpmc" },	/* am335x devices */
+	{ }
+};
+
+/**
+ * gpmc_read_settings_dt - read gpmc settings from device-tree
+ * @np:		pointer to device-tree node for a gpmc child device
+ * @p:		pointer to gpmc settings structure
+ *
+ * Reads the GPMC settings for a GPMC child device from device-tree and
+ * stores them in the GPMC settings structure passed. The GPMC settings
+ * structure is initialised to zero by this function and so any
+ * previously stored settings will be cleared.
+ */
+void gpmc_read_settings_dt(struct device_node *np, struct gpmc_settings *p)
+{
+	memset(p, 0, sizeof(struct gpmc_settings));
+
+	p->sync_read = of_property_read_bool(np, "gpmc,sync-read");
+	p->sync_write = of_property_read_bool(np, "gpmc,sync-write");
+	of_property_read_u32(np, "gpmc,device-width", &p->device_width);
+	of_property_read_u32(np, "gpmc,mux-add-data", &p->mux_add_data);
+
+	if (!of_property_read_u32(np, "gpmc,burst-length", &p->burst_len)) {
+		p->burst_wrap = of_property_read_bool(np, "gpmc,burst-wrap");
+		p->burst_read = of_property_read_bool(np, "gpmc,burst-read");
+		p->burst_write = of_property_read_bool(np, "gpmc,burst-write");
+		if (!p->burst_read && !p->burst_write)
+			pr_warn("%s: page/burst-length set but not used!\n",
+				__func__);
+	}
+
+	if (!of_property_read_u32(np, "gpmc,wait-pin", &p->wait_pin)) {
+		p->wait_on_read = of_property_read_bool(np,
+							"gpmc,wait-on-read");
+		p->wait_on_write = of_property_read_bool(np,
+							 "gpmc,wait-on-write");
+		if (!p->wait_on_read && !p->wait_on_write)
+			pr_debug("%s: rd/wr wait monitoring not enabled!\n",
+				 __func__);
+	}
+}
+
+static void __maybe_unused gpmc_read_timings_dt(struct device_node *np,
+						struct gpmc_timings *gpmc_t)
+{
+	struct gpmc_bool_timings *p;
+
+	if (!np || !gpmc_t)
+		return;
+
+	memset(gpmc_t, 0, sizeof(*gpmc_t));
+
+	/* minimum clock period for syncronous mode */
+	of_property_read_u32(np, "gpmc,sync-clk-ps", &gpmc_t->sync_clk);
+
+	/* chip select timtings */
+	of_property_read_u32(np, "gpmc,cs-on-ns", &gpmc_t->cs_on);
+	of_property_read_u32(np, "gpmc,cs-rd-off-ns", &gpmc_t->cs_rd_off);
+	of_property_read_u32(np, "gpmc,cs-wr-off-ns", &gpmc_t->cs_wr_off);
+
+	/* ADV signal timings */
+	of_property_read_u32(np, "gpmc,adv-on-ns", &gpmc_t->adv_on);
+	of_property_read_u32(np, "gpmc,adv-rd-off-ns", &gpmc_t->adv_rd_off);
+	of_property_read_u32(np, "gpmc,adv-wr-off-ns", &gpmc_t->adv_wr_off);
+	of_property_read_u32(np, "gpmc,adv-aad-mux-on-ns",
+			     &gpmc_t->adv_aad_mux_on);
+	of_property_read_u32(np, "gpmc,adv-aad-mux-rd-off-ns",
+			     &gpmc_t->adv_aad_mux_rd_off);
+	of_property_read_u32(np, "gpmc,adv-aad-mux-wr-off-ns",
+			     &gpmc_t->adv_aad_mux_wr_off);
+
+	/* WE signal timings */
+	of_property_read_u32(np, "gpmc,we-on-ns", &gpmc_t->we_on);
+	of_property_read_u32(np, "gpmc,we-off-ns", &gpmc_t->we_off);
+
+	/* OE signal timings */
+	of_property_read_u32(np, "gpmc,oe-on-ns", &gpmc_t->oe_on);
+	of_property_read_u32(np, "gpmc,oe-off-ns", &gpmc_t->oe_off);
+	of_property_read_u32(np, "gpmc,oe-aad-mux-on-ns",
+			     &gpmc_t->oe_aad_mux_on);
+	of_property_read_u32(np, "gpmc,oe-aad-mux-off-ns",
+			     &gpmc_t->oe_aad_mux_off);
+
+	/* access and cycle timings */
+	of_property_read_u32(np, "gpmc,page-burst-access-ns",
+			     &gpmc_t->page_burst_access);
+	of_property_read_u32(np, "gpmc,access-ns", &gpmc_t->access);
+	of_property_read_u32(np, "gpmc,rd-cycle-ns", &gpmc_t->rd_cycle);
+	of_property_read_u32(np, "gpmc,wr-cycle-ns", &gpmc_t->wr_cycle);
+	of_property_read_u32(np, "gpmc,bus-turnaround-ns",
+			     &gpmc_t->bus_turnaround);
+	of_property_read_u32(np, "gpmc,cycle2cycle-delay-ns",
+			     &gpmc_t->cycle2cycle_delay);
+	of_property_read_u32(np, "gpmc,wait-monitoring-ns",
+			     &gpmc_t->wait_monitoring);
+	of_property_read_u32(np, "gpmc,clk-activation-ns",
+			     &gpmc_t->clk_activation);
+
+	/* only applicable to OMAP3+ */
+	of_property_read_u32(np, "gpmc,wr-access-ns", &gpmc_t->wr_access);
+	of_property_read_u32(np, "gpmc,wr-data-mux-bus-ns",
+			     &gpmc_t->wr_data_mux_bus);
+
+	/* bool timing parameters */
+	p = &gpmc_t->bool_timings;
+
+	p->cycle2cyclediffcsen =
+		of_property_read_bool(np, "gpmc,cycle2cycle-diffcsen");
+	p->cycle2cyclesamecsen =
+		of_property_read_bool(np, "gpmc,cycle2cycle-samecsen");
+	p->we_extra_delay = of_property_read_bool(np, "gpmc,we-extra-delay");
+	p->oe_extra_delay = of_property_read_bool(np, "gpmc,oe-extra-delay");
+	p->adv_extra_delay = of_property_read_bool(np, "gpmc,adv-extra-delay");
+	p->cs_extra_delay = of_property_read_bool(np, "gpmc,cs-extra-delay");
+	p->time_para_granularity =
+		of_property_read_bool(np, "gpmc,time-para-granularity");
+}
+
+/**
+ * gpmc_probe_generic_child - configures the gpmc for a child device
+ * @pdev:	pointer to gpmc platform device
+ * @child:	pointer to device-tree node for child device
+ *
+ * Allocates and configures a GPMC chip-select for a child device.
+ * Returns 0 on success and appropriate negative error code on failure.
+ */
+static int gpmc_probe_generic_child(struct platform_device *pdev,
+				struct device_node *child)
+{
+	struct gpmc_settings gpmc_s;
+	struct gpmc_timings gpmc_t;
+	struct resource res;
+	unsigned long base;
+	const char *name;
+	int ret, cs;
+	u32 val;
+	struct gpio_desc *waitpin_desc = NULL;
+	struct gpmc_device *gpmc = platform_get_drvdata(pdev);
+
+	if (of_property_read_u32(child, "reg", &cs) < 0) {
+		dev_err(&pdev->dev, "%pOF has no 'reg' property\n",
+			child);
+		return -ENODEV;
+	}
+
+	if (of_address_to_resource(child, 0, &res) < 0) {
+		dev_err(&pdev->dev, "%pOF has malformed 'reg' property\n",
+			child);
+		return -ENODEV;
+	}
+
+	/*
+	 * Check if we have multiple instances of the same device
+	 * on a single chip select. If so, use the already initialized
+	 * timings.
+	 */
+	name = gpmc_cs_get_name(cs);
+	if (name && of_node_cmp(child->name, name) == 0)
+		goto no_timings;
+
+	ret = gpmc_cs_request(cs, resource_size(&res), &base);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "cannot request GPMC CS %d\n", cs);
+		return ret;
+	}
+	gpmc_cs_set_name(cs, child->name);
+
+	gpmc_read_settings_dt(child, &gpmc_s);
+	gpmc_read_timings_dt(child, &gpmc_t);
+
+	/*
+	 * For some GPMC devices we still need to rely on the bootloader
+	 * timings because the devices can be connected via FPGA.
+	 * REVISIT: Add timing support from slls644g.pdf.
+	 */
+	if (!gpmc_t.cs_rd_off) {
+		WARN(1, "enable GPMC debug to configure .dts timings for CS%i\n",
+			cs);
+		gpmc_cs_show_timings(cs,
+				     "please add GPMC bootloader timings to .dts");
+		goto no_timings;
+	}
+
+	/* CS must be disabled while making changes to gpmc configuration */
+	gpmc_cs_disable_mem(cs);
+
+	/*
+	 * FIXME: gpmc_cs_request() will map the CS to an arbitary
+	 * location in the gpmc address space. When booting with
+	 * device-tree we want the NOR flash to be mapped to the
+	 * location specified in the device-tree blob. So remap the
+	 * CS to this location. Once DT migration is complete should
+	 * just make gpmc_cs_request() map a specific address.
+	 */
+	ret = gpmc_cs_remap(cs, res.start);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "cannot remap GPMC CS %d to %pa\n",
+			cs, &res.start);
+		if (res.start < GPMC_MEM_START) {
+			dev_info(&pdev->dev,
+				 "GPMC CS %d start cannot be lesser than 0x%x\n",
+				 cs, GPMC_MEM_START);
+		} else if (res.end > GPMC_MEM_END) {
+			dev_info(&pdev->dev,
+				 "GPMC CS %d end cannot be greater than 0x%x\n",
+				 cs, GPMC_MEM_END);
+		}
+		goto err;
+	}
+
+	if (of_node_cmp(child->name, "nand") == 0) {
+		/* Warn about older DT blobs with no compatible property */
+		if (!of_property_read_bool(child, "compatible")) {
+			dev_warn(&pdev->dev,
+				 "Incompatible NAND node: missing compatible");
+			ret = -EINVAL;
+			goto err;
+		}
+	}
+
+	if (of_node_cmp(child->name, "onenand") == 0) {
+		/* Warn about older DT blobs with no compatible property */
+		if (!of_property_read_bool(child, "compatible")) {
+			dev_warn(&pdev->dev,
+				 "Incompatible OneNAND node: missing compatible");
+			ret = -EINVAL;
+			goto err;
+		}
+	}
+
+	if (of_device_is_compatible(child, "ti,omap2-nand")) {
+		/* NAND specific setup */
+		val = 8;
+		of_property_read_u32(child, "nand-bus-width", &val);
+		switch (val) {
+		case 8:
+			gpmc_s.device_width = GPMC_DEVWIDTH_8BIT;
+			break;
+		case 16:
+			gpmc_s.device_width = GPMC_DEVWIDTH_16BIT;
+			break;
+		default:
+			dev_err(&pdev->dev, "%s: invalid 'nand-bus-width'\n",
+				child->name);
+			ret = -EINVAL;
+			goto err;
+		}
+
+		/* disable write protect */
+		gpmc_configure(GPMC_CONFIG_WP, 0);
+		gpmc_s.device_nand = true;
+	} else {
+		ret = of_property_read_u32(child, "bank-width",
+					   &gpmc_s.device_width);
+		if (ret < 0 && !gpmc_s.device_width) {
+			dev_err(&pdev->dev,
+				"%pOF has no 'gpmc,device-width' property\n",
+				child);
+			goto err;
+		}
+	}
+
+	/* Reserve wait pin if it is required and valid */
+	if (gpmc_s.wait_on_read || gpmc_s.wait_on_write) {
+		unsigned int wait_pin = gpmc_s.wait_pin;
+
+		waitpin_desc = gpiochip_request_own_desc(&gpmc->gpio_chip,
+							 wait_pin, "WAITPIN");
+		if (IS_ERR(waitpin_desc)) {
+			dev_err(&pdev->dev, "invalid wait-pin: %d\n", wait_pin);
+			ret = PTR_ERR(waitpin_desc);
+			goto err;
+		}
+	}
+
+	gpmc_cs_show_timings(cs, "before gpmc_cs_program_settings");
+
+	ret = gpmc_cs_program_settings(cs, &gpmc_s);
+	if (ret < 0)
+		goto err_cs;
+
+	ret = gpmc_cs_set_timings(cs, &gpmc_t, &gpmc_s);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to set gpmc timings for: %s\n",
+			child->name);
+		goto err_cs;
+	}
+
+	/* Clear limited address i.e. enable A26-A11 */
+	val = gpmc_read_reg(GPMC_CONFIG);
+	val &= ~GPMC_CONFIG_LIMITEDADDRESS;
+	gpmc_write_reg(GPMC_CONFIG, val);
+
+	/* Enable CS region */
+	gpmc_cs_enable_mem(cs);
+
+no_timings:
+
+	/* create platform device, NULL on error or when disabled */
+	if (!of_platform_device_create(child, NULL, &pdev->dev))
+		goto err_child_fail;
+
+	/* is child a common bus? */
+	if (of_match_node(of_default_bus_match_table, child))
+		/* create children and other common bus children */
+		if (of_platform_default_populate(child, NULL, &pdev->dev))
+			goto err_child_fail;
+
+	return 0;
+
+err_child_fail:
+
+	dev_err(&pdev->dev, "failed to create gpmc child %s\n", child->name);
+	ret = -ENODEV;
+
+err_cs:
+	gpiochip_free_own_desc(waitpin_desc);
+err:
+	gpmc_cs_free(cs);
+
+	return ret;
+}
+
+static int gpmc_probe_dt(struct platform_device *pdev)
+{
+	int ret;
+	const struct of_device_id *of_id =
+		of_match_device(gpmc_dt_ids, &pdev->dev);
+
+	if (!of_id)
+		return 0;
+
+	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-cs",
+				   &gpmc_cs_num);
+	if (ret < 0) {
+		pr_err("%s: number of chip-selects not defined\n", __func__);
+		return ret;
+	} else if (gpmc_cs_num < 1) {
+		pr_err("%s: all chip-selects are disabled\n", __func__);
+		return -EINVAL;
+	} else if (gpmc_cs_num > GPMC_CS_NUM) {
+		pr_err("%s: number of supported chip-selects cannot be > %d\n",
+					 __func__, GPMC_CS_NUM);
+		return -EINVAL;
+	}
+
+	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-waitpins",
+				   &gpmc_nr_waitpins);
+	if (ret < 0) {
+		pr_err("%s: number of wait pins not found!\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void gpmc_probe_dt_children(struct platform_device *pdev)
+{
+	int ret;
+	struct device_node *child;
+
+	for_each_available_child_of_node(pdev->dev.of_node, child) {
+
+		if (!child->name)
+			continue;
+
+		ret = gpmc_probe_generic_child(pdev, child);
+		if (ret) {
+			dev_err(&pdev->dev, "failed to probe DT child '%s': %d\n",
+				child->name, ret);
+		}
+	}
+}
+#else
+void gpmc_read_settings_dt(struct device_node *np, struct gpmc_settings *p)
+{
+	memset(p, 0, sizeof(*p));
+}
+static int gpmc_probe_dt(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static void gpmc_probe_dt_children(struct platform_device *pdev)
+{
+}
+#endif /* CONFIG_OF */
+
+static int gpmc_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+	return 1;	/* we're input only */
+}
+
+static int gpmc_gpio_direction_input(struct gpio_chip *chip,
+				     unsigned int offset)
+{
+	return 0;	/* we're input only */
+}
+
+static int gpmc_gpio_direction_output(struct gpio_chip *chip,
+				      unsigned int offset, int value)
+{
+	return -EINVAL;	/* we're input only */
+}
+
+static void gpmc_gpio_set(struct gpio_chip *chip, unsigned int offset,
+			  int value)
+{
+}
+
+static int gpmc_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	u32 reg;
+
+	offset += 8;
+
+	reg = gpmc_read_reg(GPMC_STATUS) & BIT(offset);
+
+	return !!reg;
+}
+
+static int gpmc_gpio_init(struct gpmc_device *gpmc)
+{
+	int ret;
+
+	gpmc->gpio_chip.parent = gpmc->dev;
+	gpmc->gpio_chip.owner = THIS_MODULE;
+	gpmc->gpio_chip.label = DEVICE_NAME;
+	gpmc->gpio_chip.ngpio = gpmc_nr_waitpins;
+	gpmc->gpio_chip.get_direction = gpmc_gpio_get_direction;
+	gpmc->gpio_chip.direction_input = gpmc_gpio_direction_input;
+	gpmc->gpio_chip.direction_output = gpmc_gpio_direction_output;
+	gpmc->gpio_chip.set = gpmc_gpio_set;
+	gpmc->gpio_chip.get = gpmc_gpio_get;
+	gpmc->gpio_chip.base = -1;
+
+	ret = devm_gpiochip_add_data(gpmc->dev, &gpmc->gpio_chip, NULL);
+	if (ret < 0) {
+		dev_err(gpmc->dev, "could not register gpio chip: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int gpmc_probe(struct platform_device *pdev)
+{
+	int rc;
+	u32 l;
+	struct resource *res;
+	struct gpmc_device *gpmc;
+
+	gpmc = devm_kzalloc(&pdev->dev, sizeof(*gpmc), GFP_KERNEL);
+	if (!gpmc)
+		return -ENOMEM;
+
+	gpmc->dev = &pdev->dev;
+	platform_set_drvdata(pdev, gpmc);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL)
+		return -ENOENT;
+
+	phys_base = res->start;
+	mem_size = resource_size(res);
+
+	gpmc_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(gpmc_base))
+		return PTR_ERR(gpmc_base);
+
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get resource: irq\n");
+		return -ENOENT;
+	}
+
+	gpmc->irq = res->start;
+
+	gpmc_l3_clk = devm_clk_get(&pdev->dev, "fck");
+	if (IS_ERR(gpmc_l3_clk)) {
+		dev_err(&pdev->dev, "Failed to get GPMC fck\n");
+		return PTR_ERR(gpmc_l3_clk);
+	}
+
+	if (!clk_get_rate(gpmc_l3_clk)) {
+		dev_err(&pdev->dev, "Invalid GPMC fck clock rate\n");
+		return -EINVAL;
+	}
+
+	if (pdev->dev.of_node) {
+		rc = gpmc_probe_dt(pdev);
+		if (rc)
+			return rc;
+	} else {
+		gpmc_cs_num = GPMC_CS_NUM;
+		gpmc_nr_waitpins = GPMC_NR_WAITPINS;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	l = gpmc_read_reg(GPMC_REVISION);
+
+	/*
+	 * FIXME: Once device-tree migration is complete the below flags
+	 * should be populated based upon the device-tree compatible
+	 * string. For now just use the IP revision. OMAP3+ devices have
+	 * the wr_access and wr_data_mux_bus register fields. OMAP4+
+	 * devices support the addr-addr-data multiplex protocol.
+	 *
+	 * GPMC IP revisions:
+	 * - OMAP24xx			= 2.0
+	 * - OMAP3xxx			= 5.0
+	 * - OMAP44xx/54xx/AM335x	= 6.0
+	 */
+	if (GPMC_REVISION_MAJOR(l) > 0x4)
+		gpmc_capability = GPMC_HAS_WR_ACCESS | GPMC_HAS_WR_DATA_MUX_BUS;
+	if (GPMC_REVISION_MAJOR(l) > 0x5)
+		gpmc_capability |= GPMC_HAS_MUX_AAD;
+	dev_info(gpmc->dev, "GPMC revision %d.%d\n", GPMC_REVISION_MAJOR(l),
+		 GPMC_REVISION_MINOR(l));
+
+	gpmc_mem_init();
+	rc = gpmc_gpio_init(gpmc);
+	if (rc)
+		goto gpio_init_failed;
+
+	gpmc->nirqs = GPMC_NR_NAND_IRQS + gpmc_nr_waitpins;
+	rc = gpmc_setup_irq(gpmc);
+	if (rc) {
+		dev_err(gpmc->dev, "gpmc_setup_irq failed\n");
+		goto gpio_init_failed;
+	}
+
+	gpmc_probe_dt_children(pdev);
+
+	return 0;
+
+gpio_init_failed:
+	gpmc_mem_exit();
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return rc;
+}
+
+static int gpmc_remove(struct platform_device *pdev)
+{
+	struct gpmc_device *gpmc = platform_get_drvdata(pdev);
+
+	gpmc_free_irq(gpmc);
+	gpmc_mem_exit();
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int gpmc_suspend(struct device *dev)
+{
+	omap3_gpmc_save_context();
+	pm_runtime_put_sync(dev);
+	return 0;
+}
+
+static int gpmc_resume(struct device *dev)
+{
+	pm_runtime_get_sync(dev);
+	omap3_gpmc_restore_context();
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(gpmc_pm_ops, gpmc_suspend, gpmc_resume);
+
+static struct platform_driver gpmc_driver = {
+	.probe		= gpmc_probe,
+	.remove		= gpmc_remove,
+	.driver		= {
+		.name	= DEVICE_NAME,
+		.of_match_table = of_match_ptr(gpmc_dt_ids),
+		.pm	= &gpmc_pm_ops,
+	},
+};
+
+static __init int gpmc_init(void)
+{
+	return platform_driver_register(&gpmc_driver);
+}
+postcore_initcall(gpmc_init);
+
+static struct omap3_gpmc_regs gpmc_context;
+
+void omap3_gpmc_save_context(void)
+{
+	int i;
+
+	if (!gpmc_base)
+		return;
+
+	gpmc_context.sysconfig = gpmc_read_reg(GPMC_SYSCONFIG);
+	gpmc_context.irqenable = gpmc_read_reg(GPMC_IRQENABLE);
+	gpmc_context.timeout_ctrl = gpmc_read_reg(GPMC_TIMEOUT_CONTROL);
+	gpmc_context.config = gpmc_read_reg(GPMC_CONFIG);
+	gpmc_context.prefetch_config1 = gpmc_read_reg(GPMC_PREFETCH_CONFIG1);
+	gpmc_context.prefetch_config2 = gpmc_read_reg(GPMC_PREFETCH_CONFIG2);
+	gpmc_context.prefetch_control = gpmc_read_reg(GPMC_PREFETCH_CONTROL);
+	for (i = 0; i < gpmc_cs_num; i++) {
+		gpmc_context.cs_context[i].is_valid = gpmc_cs_mem_enabled(i);
+		if (gpmc_context.cs_context[i].is_valid) {
+			gpmc_context.cs_context[i].config1 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG1);
+			gpmc_context.cs_context[i].config2 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG2);
+			gpmc_context.cs_context[i].config3 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG3);
+			gpmc_context.cs_context[i].config4 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG4);
+			gpmc_context.cs_context[i].config5 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG5);
+			gpmc_context.cs_context[i].config6 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG6);
+			gpmc_context.cs_context[i].config7 =
+				gpmc_cs_read_reg(i, GPMC_CS_CONFIG7);
+		}
+	}
+}
+
+void omap3_gpmc_restore_context(void)
+{
+	int i;
+
+	if (!gpmc_base)
+		return;
+
+	gpmc_write_reg(GPMC_SYSCONFIG, gpmc_context.sysconfig);
+	gpmc_write_reg(GPMC_IRQENABLE, gpmc_context.irqenable);
+	gpmc_write_reg(GPMC_TIMEOUT_CONTROL, gpmc_context.timeout_ctrl);
+	gpmc_write_reg(GPMC_CONFIG, gpmc_context.config);
+	gpmc_write_reg(GPMC_PREFETCH_CONFIG1, gpmc_context.prefetch_config1);
+	gpmc_write_reg(GPMC_PREFETCH_CONFIG2, gpmc_context.prefetch_config2);
+	gpmc_write_reg(GPMC_PREFETCH_CONTROL, gpmc_context.prefetch_control);
+	for (i = 0; i < gpmc_cs_num; i++) {
+		if (gpmc_context.cs_context[i].is_valid) {
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG1,
+				gpmc_context.cs_context[i].config1);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG2,
+				gpmc_context.cs_context[i].config2);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG3,
+				gpmc_context.cs_context[i].config3);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG4,
+				gpmc_context.cs_context[i].config4);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG5,
+				gpmc_context.cs_context[i].config5);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG6,
+				gpmc_context.cs_context[i].config6);
+			gpmc_cs_write_reg(i, GPMC_CS_CONFIG7,
+				gpmc_context.cs_context[i].config7);
+		}
+	}
+}