ARM: omap: merge GPMC initialization code for all platform

GPMC controller on TI's OMAP SoC is general purpose controller to interface
with different types of external devices like;
 - parallel NOR flash
 - parallel NAND flash
 - OneNand flash
 - SDR RAM
 - Ethernet Devices like LAN9220

Though GPMC configurations may be different for each platform depending on
clock-frequency and external device interfacing with controller. But
initialization sequence remains common across all platfoms.

Thus this patch merges gpmc_init() scattered in different arch-xx/mem.c
files into single omap-common/mem-common.c

However, actual platforms specific register config values are still sourced
from corresponding platform specific headers like;
 AM33xx: arch/arm/include/asm/arch-am33xx/mem.h
 OMAP3:  arch/arm/include/asm/arch-omap3/mem.h
 OMAP4:  arch/arm/include/asm/arch-omap4/mem.h
 OMAP4:  arch/arm/include/asm/arch-omap5/mem.h

Also, CONFIG_xx passed by board-profile decide config for which set of macros
need to be used for initialization
 CONFIG_NAND:    initialize GPMC for NAND device
 CONFIG_NOR:     initialize GPMC for NOR device
 CONFIG_ONENAND: initialize GPMC for ONENAND device

Signed-off-by: Pekon Gupta <pekon@ti.com>
[trini: define GPMC_SIZE_256M for omap3]
Signed-off-by: Tom Rini <trini@ti.com>
diff --git a/arch/arm/cpu/armv7/omap-common/mem-common.c b/arch/arm/cpu/armv7/omap-common/mem-common.c
index afc1bc1..944ef84 100644
--- a/arch/arm/cpu/armv7/omap-common/mem-common.c
+++ b/arch/arm/cpu/armv7/omap-common/mem-common.c
@@ -2,31 +2,136 @@
  * (C) Copyright 2010
  * Texas Instruments, <www.ti.com>
  *
- * Steve Sakoman <steve@sakoman.com>
+ * Author :
+ *     Mansoor Ahamed <mansoor.ahamed@ti.com>
+ *
+ * Initial Code from:
+ *     Manikandan Pillai <mani.pillai@ti.com>
+ *     Richard Woodruff <r-woodruff2@ti.com>
+ *     Syed Mohammed Khasim <khasim@ti.com>
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
 
+#include <common.h>
+#include <asm/io.h>
 #include <asm/arch/cpu.h>
+#include <asm/arch/mem.h>
 #include <asm/arch/sys_proto.h>
+#include <command.h>
+#include <linux/mtd/omap_gpmc.h>
 
 struct gpmc *gpmc_cfg;
 
+#if defined(CONFIG_OMAP34XX)
+/********************************************************
+ *  mem_ok() - test used to see if timings are correct
+ *             for a part. Helps in guessing which part
+ *             we are currently using.
+ *******************************************************/
+u32 mem_ok(u32 cs)
+{
+	u32 val1, val2, addr;
+	u32 pattern = 0x12345678;
+
+	addr = OMAP34XX_SDRC_CS0 + get_sdr_cs_offset(cs);
+
+	writel(0x0, addr + 0x400);	/* clear pos A */
+	writel(pattern, addr);		/* pattern to pos B */
+	writel(0x0, addr + 4);		/* remove pattern off the bus */
+	val1 = readl(addr + 0x400);	/* get pos A value */
+	val2 = readl(addr);		/* get val2 */
+	writel(0x0, addr + 0x400);	/* clear pos A */
+
+	if ((val1 != 0) || (val2 != pattern))	/* see if pos A val changed */
+		return 0;
+	else
+		return 1;
+}
+#endif
+
+void enable_gpmc_cs_config(const u32 *gpmc_config, struct gpmc_cs *cs, u32 base,
+			u32 size)
+{
+	writel(0, &cs->config7);
+	sdelay(1000);
+	/* Delay for settling */
+	writel(gpmc_config[0], &cs->config1);
+	writel(gpmc_config[1], &cs->config2);
+	writel(gpmc_config[2], &cs->config3);
+	writel(gpmc_config[3], &cs->config4);
+	writel(gpmc_config[4], &cs->config5);
+	writel(gpmc_config[5], &cs->config6);
+	/* Enable the config */
+	writel((((size & 0xF) << 8) | ((base >> 24) & 0x3F) |
+		(1 << 6)), &cs->config7);
+	sdelay(2000);
+}
+
 /*****************************************************
  * gpmc_init(): init gpmc bus
+ * Init GPMC for x16, MuxMode (SDRAM in x32).
  * This code can only be executed from SRAM or SDRAM.
  *****************************************************/
 void gpmc_init(void)
 {
+	/* putting a blanket check on GPMC based on ZeBu for now */
 	gpmc_cfg = (struct gpmc *)GPMC_BASE;
-
+#if defined(CONFIG_NOR)
+/* configure GPMC for NOR */
+	const u32 gpmc_regs[GPMC_MAX_REG] = {	STNOR_GPMC_CONFIG1,
+						STNOR_GPMC_CONFIG2,
+						STNOR_GPMC_CONFIG3,
+						STNOR_GPMC_CONFIG4,
+						STNOR_GPMC_CONFIG5,
+						STNOR_GPMC_CONFIG6,
+						STNOR_GPMC_CONFIG7
+						};
+	u32 size = GPMC_SIZE_16M;
+	u32 base = CONFIG_SYS_FLASH_BASE;
+#elif defined(CONFIG_NAND)
+/* configure GPMC for NAND */
+	const u32  gpmc_regs[GPMC_MAX_REG] = {	M_NAND_GPMC_CONFIG1,
+						M_NAND_GPMC_CONFIG2,
+						M_NAND_GPMC_CONFIG3,
+						M_NAND_GPMC_CONFIG4,
+						M_NAND_GPMC_CONFIG5,
+						M_NAND_GPMC_CONFIG6,
+						0
+						};
+	u32 size = GPMC_SIZE_256M;
+	u32 base = CONFIG_SYS_NAND_BASE;
+#elif defined(CONFIG_CMD_ONENAND)
+	const u32 gpmc_regs[GPMC_MAX_REG] = {	ONENAND_GPMC_CONFIG1,
+						ONENAND_GPMC_CONFIG2,
+						ONENAND_GPMC_CONFIG3,
+						ONENAND_GPMC_CONFIG4,
+						ONENAND_GPMC_CONFIG5,
+						ONENAND_GPMC_CONFIG6,
+						0
+						};
+	u32 base = PISMO1_ONEN_BASE;
+	u32 size = PISMO1_ONEN_SIZE;
+#else
+	const u32 gpmc_regs[GPMC_MAX_REG] = { 0, 0, 0, 0, 0, 0, 0 };
+	u32 size = 0;
+	u32 base = 0;
+#endif
 	/* global settings */
-	writel(0, &gpmc_cfg->irqenable); /* isr's sources masked */
-	writel(0, &gpmc_cfg->timeout_control);/* timeout disable */
-
+	writel(0x00000008, &gpmc_cfg->sysconfig);
+	writel(0x00000000, &gpmc_cfg->irqstatus);
+	writel(0x00000000, &gpmc_cfg->irqenable);
+	writel(0x00000000, &gpmc_cfg->timeout_control);
+#ifdef CONFIG_NOR
+	writel(0x00000200, &gpmc_cfg->config);
+#else
+	writel(0x00000012, &gpmc_cfg->config);
+#endif
 	/*
 	 * Disable the GPMC0 config set by ROM code
-	 * It conflicts with our MPDB (both at 0x08000000)
 	 */
 	writel(0, &gpmc_cfg->cs[0].config7);
+	sdelay(1000);
+	/* enable chip-select specific configurations */
+	enable_gpmc_cs_config(gpmc_regs, &gpmc_cfg->cs[0], base, size);
 }