Merge tag 'omap-gpmc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc

Pull ARM SoC/OMAP GPMC driver cleanup and move from Arnd Bergmann:
 "The GPMC driver has traditionally been considered a part of the OMAP
  platform code and tightly interweaved with some of the boards.

  With this cleanup, it has finally come to the point where it makes
  sense to move it out of arch/arm into drivers/memory, where we already
  have other drivers for similar hardware.  The cleanups are still
  ongoing, with the goal of eventually having a standalone driver that
  does not require an interface to architecture code.

  This is a separate branch because of dependencies on multiple other
  branches, and to keep the drivers changes separate from the normal
  cleanups"

* tag 'omap-gpmc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  memory: gpmc: Move omap gpmc code to live under drivers
  ARM: OMAP2+: Move GPMC initcall to devices.c
  ARM: OMAP2+: Prepare to move GPMC to drivers by platform data header
  ARM: OMAP2+: Remove unnecesary include in GPMC driver
  ARM: OMAP2+: Drop board file for 3430sdp
  ARM: OMAP2+: Drop board file for ti8168evm
  ARM: OMAP2+: Drop legacy code for gpmc-smc91x.c
  ARM: OMAP2+: Require proper GPMC timings for devices
  ARM: OMAP2+: Show bootloader GPMC timings to allow configuring the .dts file
  ARM: OMAP2+: Fix support for multiple devices on a GPMC chip select
  ARM: OMAP2+: gpmc: Sanity check GPMC fck on probe
  ARM: OMAP2+: gpmc: Keep Chip Select disabled while configuring it
  ARM: OMAP2+: gpmc: Always enable A26-A11 for non NAND devices
  ARM: OMAP2+: gpmc: Error out if timings fail in gpmc_probe_generic_child()
  ARM: OMAP2+: gpmc: Print error message in set_gpmc_timing_reg()

3 files changed, 2101 insertions, 0 deletions

diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index 08bd4cf..191383d8 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -41,6 +41,14 @@ config TI_EMIF
 	  parameters and other settings during frequency, voltage and
 	  temperature changes
 
+config OMAP_GPMC
+	bool
+	help
+	  This driver is for the General Purpose Memory Controller (GPMC)
+	  present on Texas Instruments SoCs (e.g. OMAP2+). GPMC allows
+	  interfacing to a variety of asynchronous as well as synchronous
+	  memory drives like NOR, NAND, OneNAND, SRAM.
+
 config MVEBU_DEVBUS
 	bool "Marvell EBU Device Bus Controller"
 	default y
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index ad98bb2..6b65481 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -8,6 +8,7 @@ endif
 obj-$(CONFIG_ATMEL_SDRAMC)	+= atmel-sdramc.o
 obj-$(CONFIG_TI_AEMIF)		+= ti-aemif.o
 obj-$(CONFIG_TI_EMIF)		+= emif.o
+obj-$(CONFIG_OMAP_GPMC)		+= omap-gpmc.o
 obj-$(CONFIG_FSL_CORENET_CF)	+= fsl-corenet-cf.o
 obj-$(CONFIG_FSL_IFC)		+= fsl_ifc.o
 obj-$(CONFIG_MVEBU_DEVBUS)	+= mvebu-devbus.o
diff --git a/drivers/memory/omap-gpmc.c b/drivers/memory/omap-gpmc.c
new file mode 100644
index 0000000..ffc5e60
--- /dev/null
+++ b/drivers/memory/omap-gpmc.c
@@ -0,0 +1,2092 @@
+/*
+ * 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.
+ */
+#undef DEBUG
+
+#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/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_mtd.h>
+#include <linux/of_device.h>
+#include <linux/omap-gpmc.h>
+#include <linux/mtd/nand.h>
+#include <linux/pm_runtime.h>
+
+#include <linux/platform_data/mtd-nand-omap2.h>
+#include <linux/platform_data/mtd-onenand-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_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
+
+#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_SET_IRQ_STATUS	0x00000004
+
+#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)
+#define GPMC_CONFIG1_PAGE_LEN(val)      ((val & 3) << 23)
+#define GPMC_CONFIG1_WAIT_READ_MON      (1 << 22)
+#define GPMC_CONFIG1_WAIT_WRITE_MON     (1 << 21)
+#define GPMC_CONFIG1_WAIT_MON_IIME(val) ((val & 3) << 18)
+#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)
+#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_DEVICETYPE_NOR		0
+#define GPMC_DEVICETYPE_NAND		2
+#define GPMC_CONFIG_WRITEPROTECT	0x00000010
+#define WR_RD_PIN_MONITORING		0x00600000
+
+#define GPMC_ENABLE_IRQ		0x0000000d
+
+/* 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 */
+
+/* XXX: Only NAND irq has been considered,currently these are the only ones used
+ */
+#define	GPMC_NR_IRQ		2
+
+struct gpmc_cs_data {
+	const char *name;
+
+#define GPMC_CS_RESERVED	(1 << 0)
+	u32 flags;
+
+	struct resource mem;
+};
+
+struct gpmc_client_irq	{
+	unsigned		irq;
+	u32			bitmask;
+};
+
+/* 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];
+};
+
+static struct gpmc_client_irq gpmc_client_irq[GPMC_NR_IRQ];
+static struct irq_chip gpmc_irq_chip;
+static int gpmc_irq_start;
+
+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 struct device *gpmc_dev;
+static int gpmc_irq;
+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;
+}
+
+static unsigned int gpmc_ns_to_ticks(unsigned int time_ns)
+{
+	unsigned long tick_ps;
+
+	/* Calculate in picosecs to yield more exact results */
+	tick_ps = gpmc_get_fclk_period();
+
+	return (time_ns * 1000 + tick_ps - 1) / tick_ps;
+}
+
+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;
+}
+
+unsigned int gpmc_ticks_to_ns(unsigned int ticks)
+{
+	return ticks * gpmc_get_fclk_period() / 1000;
+}
+
+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_OEEXTRADELAY, 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 DEBUG
+static int get_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
+			       bool raw, bool noval, int shift,
+			       const char *name)
+{
+	u32 l;
+	int nr_bits, max_value, mask;
+
+	l = gpmc_cs_read_reg(cs, reg);
+	nr_bits = end_bit - st_bit + 1;
+	max_value = (1 << nr_bits) - 1;
+	mask = max_value << st_bit;
+	l = (l & mask) >> st_bit;
+	if (shift)
+		l = (shift << l);
+	if (noval && (l == 0))
+		return 0;
+	if (!raw) {
+		unsigned int time_ns_min, time_ns, time_ns_max;
+
+		time_ns_min = gpmc_ticks_to_ns(l ? l - 1 : 0);
+		time_ns = gpmc_ticks_to_ns(l);
+		time_ns_max = gpmc_ticks_to_ns(l + 1 > max_value ?
+					       max_value : l + 1);
+		pr_info("gpmc,%s = <%u> (%u - %u ns, %i ticks)\n",
+			name, time_ns, time_ns_min, time_ns_max, l);
+	} else {
+		pr_info("gpmc,%s = <%u>\n", name, l);
+	}
+
+	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), 1, 0, 0, field)
+#define GPMC_GET_RAW_BOOL(reg, st, end, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 1, 1, 0, field)
+#define GPMC_GET_RAW_SHIFT(reg, st, end, shift, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 1, 1, (shift), field)
+#define GPMC_GET_TICKS(reg, st, end, field) \
+	get_gpmc_timing_reg(cs, (reg), (st), (end), 0, 0, 0, field)
+
+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(GPMC_CS_CONFIG1, 12, 13, "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(GPMC_CS_CONFIG1, 23, 24, 4, "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");
+
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4,  0,  3, "oe-on-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG4,  8, 12, "oe-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(GPMC_CS_CONFIG1, 18, 19, "wait-monitoring-ns");
+	GPMC_GET_TICKS(GPMC_CS_CONFIG1, 25, 26, "clk-activation-ns");
+
+	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
+
+static int set_gpmc_timing_reg(int cs, int reg, int st_bit, int end_bit,
+			       int time, const char *name)
+{
+	u32 l;
+	int ticks, mask, nr_bits;
+
+	if (time == 0)
+		ticks = 0;
+	else
+		ticks = gpmc_ns_to_ticks(time);
+	nr_bits = end_bit - st_bit + 1;
+	mask = (1 << nr_bits) - 1;
+
+	if (ticks > mask) {
+		pr_err("%s: GPMC error! CS%d: %s: %d ns, %d ticks > %d\n",
+		       __func__, cs, name, time, ticks, mask);
+
+		return -1;
+	}
+
+	l = gpmc_cs_read_reg(cs, reg);
+#ifdef DEBUG
+	printk(KERN_INFO
+		"GPMC CS%d: %-10s: %3d ticks, %3lu ns (was %3i ticks) %3d ns\n",
+	       cs, name, ticks, gpmc_get_fclk_period() * 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(reg, st, end, field) \
+	if (set_gpmc_timing_reg(cs, (reg), (st), (end),		\
+			t->field, #field) < 0)			\
+		return -1
+
+int gpmc_calc_divider(unsigned int sync_clk)
+{
+	int div;
+	u32 l;
+
+	l = sync_clk + (gpmc_get_fclk_period() - 1);
+	div = l / gpmc_get_fclk_period();
+	if (div > 4)
+		return -1;
+	if (div <= 0)
+		div = 1;
+
+	return div;
+}
+
+int gpmc_cs_set_timings(int cs, const struct gpmc_timings *t)
+{
+	int div;
+	u32 l;
+
+	gpmc_cs_show_timings(cs, "before gpmc_cs_set_timings");
+	div = gpmc_calc_divider(t->sync_clk);
+	if (div < 0)
+		return div;
+
+	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);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG4,  0,  3, oe_on);
+	GPMC_SET_ONE(GPMC_CS_CONFIG4,  8, 12, oe_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);
+
+	GPMC_SET_ONE(GPMC_CS_CONFIG1, 18, 19, wait_monitoring);
+	GPMC_SET_ONE(GPMC_CS_CONFIG1, 25, 26, clk_activation);
+
+	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);
+
+	/* caller is expected to have initialized CONFIG1 to cover
+	 * at least sync vs async
+	 */
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG1);
+	if (l & (GPMC_CONFIG1_READTYPE_SYNC | GPMC_CONFIG1_WRITETYPE_SYNC)) {
+#ifdef DEBUG
+		printk(KERN_INFO "GPMC CS%d CLK period is %lu ns (div %d)\n",
+				cs, (div * gpmc_get_fclk_period()) / 1000, div);
+#endif
+		l &= ~0x03;
+		l |= (div - 1);
+		gpmc_cs_write_reg(cs, GPMC_CS_CONFIG1, l);
+	}
+
+	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;
+
+	mask = (1 << GPMC_SECTION_SHIFT) - size;
+	l = gpmc_cs_read_reg(cs, GPMC_CS_CONFIG7);
+	l &= ~0x3f;
+	l = (base >> GPMC_CHUNK_SHIFT) & 0x3f;
+	l &= ~(0x0f << 8);
+	l |= ((mask >> GPMC_CHUNK_SHIFT) & 0x0f) << 8;
+	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;
+}
+
+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 = &gpmc_cs[cs];
+	struct resource *res = &gpmc->mem;
+
+	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_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_ENABLE_IRQ:
+		gpmc_write_reg(GPMC_IRQENABLE, wval);
+		break;
+
+	case GPMC_SET_IRQ_STATUS:
+		gpmc_write_reg(GPMC_IRQSTATUS, wval);
+		break;
+
+	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);
+
+void gpmc_update_nand_reg(struct gpmc_nand_regs *reg, int cs)
+{
+	int i;
+
+	reg->gpmc_status = gpmc_base + GPMC_STATUS;
+	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;
+	}
+}
+
+int gpmc_get_client_irq(unsigned irq_config)
+{
+	int i;
+
+	if (hweight32(irq_config) > 1)
+		return 0;
+
+	for (i = 0; i < GPMC_NR_IRQ; i++)
+		if (gpmc_client_irq[i].bitmask & irq_config)
+			return gpmc_client_irq[i].irq;
+
+	return 0;
+}
+
+static int gpmc_irq_endis(unsigned irq, bool endis)
+{
+	int i;
+	u32 regval;
+
+	for (i = 0; i < GPMC_NR_IRQ; i++)
+		if (irq == gpmc_client_irq[i].irq) {
+			regval = gpmc_read_reg(GPMC_IRQENABLE);
+			if (endis)
+				regval |= gpmc_client_irq[i].bitmask;
+			else
+				regval &= ~gpmc_client_irq[i].bitmask;
+			gpmc_write_reg(GPMC_IRQENABLE, regval);
+			break;
+		}
+
+	return 0;
+}
+
+static void gpmc_irq_disable(struct irq_data *p)
+{
+	gpmc_irq_endis(p->irq, false);
+}
+
+static void gpmc_irq_enable(struct irq_data *p)
+{
+	gpmc_irq_endis(p->irq, true);
+}
+
+static void gpmc_irq_noop(struct irq_data *data) { }
+
+static unsigned int gpmc_irq_noop_ret(struct irq_data *data) { return 0; }
+
+static int gpmc_setup_irq(void)
+{
+	int i;
+	u32 regval;
+
+	if (!gpmc_irq)
+		return -EINVAL;
+
+	gpmc_irq_start = irq_alloc_descs(-1, 0, GPMC_NR_IRQ, 0);
+	if (gpmc_irq_start < 0) {
+		pr_err("irq_alloc_descs failed\n");
+		return gpmc_irq_start;
+	}
+
+	gpmc_irq_chip.name = "gpmc";
+	gpmc_irq_chip.irq_startup = gpmc_irq_noop_ret;
+	gpmc_irq_chip.irq_enable = gpmc_irq_enable;
+	gpmc_irq_chip.irq_disable = gpmc_irq_disable;
+	gpmc_irq_chip.irq_shutdown = gpmc_irq_noop;
+	gpmc_irq_chip.irq_ack = gpmc_irq_noop;
+	gpmc_irq_chip.irq_mask = gpmc_irq_noop;
+	gpmc_irq_chip.irq_unmask = gpmc_irq_noop;
+
+	gpmc_client_irq[0].bitmask = GPMC_IRQ_FIFOEVENTENABLE;
+	gpmc_client_irq[1].bitmask = GPMC_IRQ_COUNT_EVENT;
+
+	for (i = 0; i < GPMC_NR_IRQ; i++) {
+		gpmc_client_irq[i].irq = gpmc_irq_start + i;
+		irq_set_chip_and_handler(gpmc_client_irq[i].irq,
+					&gpmc_irq_chip, handle_simple_irq);
+		set_irq_flags(gpmc_client_irq[i].irq,
+				IRQF_VALID | IRQF_NOAUTOEN);
+	}
+
+	/* Disable interrupts */
+	gpmc_write_reg(GPMC_IRQENABLE, 0);
+
+	/* clear interrupts */
+	regval = gpmc_read_reg(GPMC_IRQSTATUS);
+	gpmc_write_reg(GPMC_IRQSTATUS, regval);
+
+	return request_irq(gpmc_irq, gpmc_handle_irq, 0, "gpmc", NULL);
+}
+
+static int gpmc_free_irq(void)
+{
+	int i;
+
+	if (gpmc_irq)
+		free_irq(gpmc_irq, NULL);
+
+	for (i = 0; i < GPMC_NR_IRQ; i++) {
+		irq_set_handler(gpmc_client_irq[i].irq, NULL);
+		irq_set_chip(gpmc_client_irq[i].irq, &no_irq_chip);
+		irq_modify_status(gpmc_client_irq[i].irq, 0, 0);
+	}
+
+	irq_free_descs(gpmc_irq_start, GPMC_NR_IRQ);
+
+	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;
+
+	/*
+	 * 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.
+	 */
+	gpmc_mem_root.start = SZ_1M;
+	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 */
+	{ }
+};
+MODULE_DEVICE_TABLE(of, gpmc_dt_ids);
+
+/**
+ * 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);
+
+	/* 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);
+
+	/* 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");
+}
+
+#if IS_ENABLED(CONFIG_MTD_NAND)
+
+static const char * const nand_xfer_types[] = {
+	[NAND_OMAP_PREFETCH_POLLED]		= "prefetch-polled",
+	[NAND_OMAP_POLLED]			= "polled",
+	[NAND_OMAP_PREFETCH_DMA]		= "prefetch-dma",
+	[NAND_OMAP_PREFETCH_IRQ]		= "prefetch-irq",
+};
+
+static int gpmc_probe_nand_child(struct platform_device *pdev,
+				 struct device_node *child)
+{
+	u32 val;
+	const char *s;
+	struct gpmc_timings gpmc_t;
+	struct omap_nand_platform_data *gpmc_nand_data;
+
+	if (of_property_read_u32(child, "reg", &val) < 0) {
+		dev_err(&pdev->dev, "%s has no 'reg' property\n",
+			child->full_name);
+		return -ENODEV;
+	}
+
+	gpmc_nand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_nand_data),
+				      GFP_KERNEL);
+	if (!gpmc_nand_data)
+		return -ENOMEM;
+
+	gpmc_nand_data->cs = val;
+	gpmc_nand_data->of_node = child;
+
+	/* Detect availability of ELM module */
+	gpmc_nand_data->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0);
+	if (gpmc_nand_data->elm_of_node == NULL)
+		gpmc_nand_data->elm_of_node =
+					of_parse_phandle(child, "elm_id", 0);
+
+	/* select ecc-scheme for NAND */
+	if (of_property_read_string(child, "ti,nand-ecc-opt", &s)) {
+		pr_err("%s: ti,nand-ecc-opt not found\n", __func__);
+		return -ENODEV;
+	}
+
+	if (!strcmp(s, "sw"))
+		gpmc_nand_data->ecc_opt = OMAP_ECC_HAM1_CODE_SW;
+	else if (!strcmp(s, "ham1") ||
+		 !strcmp(s, "hw") || !strcmp(s, "hw-romcode"))
+		gpmc_nand_data->ecc_opt =
+				OMAP_ECC_HAM1_CODE_HW;
+	else if (!strcmp(s, "bch4"))
+		if (gpmc_nand_data->elm_of_node)
+			gpmc_nand_data->ecc_opt =
+				OMAP_ECC_BCH4_CODE_HW;
+		else
+			gpmc_nand_data->ecc_opt =
+				OMAP_ECC_BCH4_CODE_HW_DETECTION_SW;
+	else if (!strcmp(s, "bch8"))
+		if (gpmc_nand_data->elm_of_node)
+			gpmc_nand_data->ecc_opt =
+				OMAP_ECC_BCH8_CODE_HW;
+		else
+			gpmc_nand_data->ecc_opt =
+				OMAP_ECC_BCH8_CODE_HW_DETECTION_SW;
+	else if (!strcmp(s, "bch16"))
+		if (gpmc_nand_data->elm_of_node)
+			gpmc_nand_data->ecc_opt =
+				OMAP_ECC_BCH16_CODE_HW;
+		else
+			pr_err("%s: BCH16 requires ELM support\n", __func__);
+	else
+		pr_err("%s: ti,nand-ecc-opt invalid value\n", __func__);
+
+	/* select data transfer mode for NAND controller */
+	if (!of_property_read_string(child, "ti,nand-xfer-type", &s))
+		for (val = 0; val < ARRAY_SIZE(nand_xfer_types); val++)
+			if (!strcasecmp(s, nand_xfer_types[val])) {
+				gpmc_nand_data->xfer_type = val;
+				break;
+			}
+
+	gpmc_nand_data->flash_bbt = of_get_nand_on_flash_bbt(child);
+
+	val = of_get_nand_bus_width(child);
+	if (val == 16)
+		gpmc_nand_data->devsize = NAND_BUSWIDTH_16;
+
+	gpmc_read_timings_dt(child, &gpmc_t);
+	gpmc_nand_init(gpmc_nand_data, &gpmc_t);
+
+	return 0;
+}
+#else
+static int gpmc_probe_nand_child(struct platform_device *pdev,
+				 struct device_node *child)
+{
+	return 0;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_MTD_ONENAND)
+static int gpmc_probe_onenand_child(struct platform_device *pdev,
+				 struct device_node *child)
+{
+	u32 val;
+	struct omap_onenand_platform_data *gpmc_onenand_data;
+
+	if (of_property_read_u32(child, "reg", &val) < 0) {
+		dev_err(&pdev->dev, "%s has no 'reg' property\n",
+			child->full_name);
+		return -ENODEV;
+	}
+
+	gpmc_onenand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_onenand_data),
+					 GFP_KERNEL);
+	if (!gpmc_onenand_data)
+		return -ENOMEM;
+
+	gpmc_onenand_data->cs = val;
+	gpmc_onenand_data->of_node = child;
+	gpmc_onenand_data->dma_channel = -1;
+
+	if (!of_property_read_u32(child, "dma-channel", &val))
+		gpmc_onenand_data->dma_channel = val;
+
+	gpmc_onenand_init(gpmc_onenand_data);
+
+	return 0;
+}
+#else
+static int gpmc_probe_onenand_child(struct platform_device *pdev,
+				    struct device_node *child)
+{
+	return 0;
+}
+#endif
+
+/**
+ * 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;
+
+	if (of_property_read_u32(child, "reg", &cs) < 0) {
+		dev_err(&pdev->dev, "%s has no 'reg' property\n",
+			child->full_name);
+		return -ENODEV;
+	}
+
+	if (of_address_to_resource(child, 0, &res) < 0) {
+		dev_err(&pdev->dev, "%s has malformed 'reg' property\n",
+			child->full_name);
+		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 && child->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);
+		goto err;
+	}
+
+	ret = of_property_read_u32(child, "bank-width", &gpmc_s.device_width);
+	if (ret < 0)
+		goto err;
+
+	ret = gpmc_cs_program_settings(cs, &gpmc_s);
+	if (ret < 0)
+		goto err;
+
+	ret = gpmc_cs_set_timings(cs, &gpmc_t);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to set gpmc timings for: %s\n",
+			child->name);
+		goto err;
+	}
+
+	/* 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:
+	if (of_platform_device_create(child, NULL, &pdev->dev))
+		return 0;
+
+	dev_err(&pdev->dev, "failed to create gpmc child %s\n", child->name);
+	ret = -ENODEV;
+
+err:
+	gpmc_cs_free(cs);
+
+	return ret;
+}
+
+static int gpmc_probe_dt(struct platform_device *pdev)
+{
+	int ret;
+	struct device_node *child;
+	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;
+	}
+
+	for_each_available_child_of_node(pdev->dev.of_node, child) {
+
+		if (!child->name)
+			continue;
+
+		if (of_node_cmp(child->name, "nand") == 0)
+			ret = gpmc_probe_nand_child(pdev, child);
+		else if (of_node_cmp(child->name, "onenand") == 0)
+			ret = gpmc_probe_onenand_child(pdev, child);
+		else if (of_node_cmp(child->name, "ethernet") == 0 ||
+			 of_node_cmp(child->name, "nor") == 0 ||
+			 of_node_cmp(child->name, "uart") == 0)
+			ret = gpmc_probe_generic_child(pdev, child);
+
+		if (WARN(ret < 0, "%s: probing gpmc child %s failed\n",
+			 __func__, child->full_name))
+			of_node_put(child);
+	}
+
+	return 0;
+}
+#else
+static int gpmc_probe_dt(struct platform_device *pdev)
+{
+	return 0;
+}
+#endif
+
+static int gpmc_probe(struct platform_device *pdev)
+{
+	int rc;
+	u32 l;
+	struct resource *res;
+
+	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 == NULL)
+		dev_warn(&pdev->dev, "Failed to get resource: irq\n");
+	else
+		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");
+		gpmc_irq = 0;
+		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;
+	}
+
+	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	gpmc_dev = &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();
+
+	if (gpmc_setup_irq() < 0)
+		dev_warn(gpmc_dev, "gpmc_setup_irq failed\n");
+
+	if (!pdev->dev.of_node) {
+		gpmc_cs_num	 = GPMC_CS_NUM;
+		gpmc_nr_waitpins = GPMC_NR_WAITPINS;
+	}
+
+	rc = gpmc_probe_dt(pdev);
+	if (rc < 0) {
+		pm_runtime_put_sync(&pdev->dev);
+		dev_err(gpmc_dev, "failed to probe DT parameters\n");
+		return rc;
+	}
+
+	return 0;
+}
+
+static int gpmc_remove(struct platform_device *pdev)
+{
+	gpmc_free_irq();
+	gpmc_mem_exit();
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	gpmc_dev = NULL;
+	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,
+		.owner	= THIS_MODULE,
+		.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);
+}
+
+static __exit void gpmc_exit(void)
+{
+	platform_driver_unregister(&gpmc_driver);
+
+}
+
+postcore_initcall(gpmc_init);
+module_exit(gpmc_exit);
+
+static irqreturn_t gpmc_handle_irq(int irq, void *dev)
+{
+	int i;
+	u32 regval;
+
+	regval = gpmc_read_reg(GPMC_IRQSTATUS);
+
+	if (!regval)
+		return IRQ_NONE;
+
+	for (i = 0; i < GPMC_NR_IRQ; i++)
+		if (regval & gpmc_client_irq[i].bitmask)
+			generic_handle_irq(gpmc_client_irq[i].irq);
+
+	gpmc_write_reg(GPMC_IRQSTATUS, regval);
+
+	return IRQ_HANDLED;
+}
+
+static struct omap3_gpmc_regs gpmc_context;
+
+void omap3_gpmc_save_context(void)
+{
+	int i;
+
+	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;
+
+	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);
+		}
+	}
+}