imx6: geam6ul: Add NAND support

Add NAND support for Engicam GEAM6UL board.

Boot Log:
--------
U-Boot SPL 2016.11-g537fa5f (Nov 28 2016 - 11:42:28)
Trying to boot from NAND
NAND : 256 MiB

U-Boot 2016.11-g537fa5f (Nov 28 2016 - 11:20:06 +0100)

CPU:   Freescale i.MX6UL rev1.1 69 MHz (running at 396 MHz)
CPU:   Automotive temperature grade (-40C to 125C) at 42C
Reset cause: WDOG
Model: Engicam GEAM6UL
DRAM:  128 MiB
NAND:  256 MiB
MMC:   FSL_SDHC: 0
* Warning - bad CRC, using default environment

In:    serial
Out:   serial
Err:   serial
Net:   No ethernet found.
Hit any key to stop autoboot:  0

Cc: Stefano Babic <sbabic@denx.de>
Cc: Matteo Lisi <matteo.lisi@engicam.com>
Cc: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/board/engicam/geam6ul/geam6ul.c b/board/engicam/geam6ul/geam6ul.c
index 8530845..40f20a9 100644
--- a/board/engicam/geam6ul/geam6ul.c
+++ b/board/engicam/geam6ul/geam6ul.c
@@ -13,6 +13,7 @@
 #include <linux/sizes.h>
 
 #include <asm/arch/clock.h>
+#include <asm/arch/crm_regs.h>
 #include <asm/arch/iomux.h>
 #include <asm/arch/mx6-pins.h>
 #include <asm/arch/sys_proto.h>
@@ -36,11 +37,81 @@
 	return 0;
 }
 
+#ifdef CONFIG_NAND_MXS
+
+#define GPMI_PAD_CTRL0		(PAD_CTL_PKE | PAD_CTL_PUE | PAD_CTL_PUS_100K_UP)
+#define GPMI_PAD_CTRL1		(PAD_CTL_DSE_40ohm | PAD_CTL_SPEED_MED | \
+				PAD_CTL_SRE_FAST)
+#define GPMI_PAD_CTRL2		(GPMI_PAD_CTRL0 | GPMI_PAD_CTRL1)
+
+static iomux_v3_cfg_t const nand_pads[] = {
+	MX6_PAD_NAND_DATA00__RAWNAND_DATA00 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA01__RAWNAND_DATA01 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA02__RAWNAND_DATA02 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA03__RAWNAND_DATA03 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA04__RAWNAND_DATA04 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA05__RAWNAND_DATA05 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA06__RAWNAND_DATA06 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_DATA07__RAWNAND_DATA07 | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_CLE__RAWNAND_CLE | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_ALE__RAWNAND_ALE | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_CE0_B__RAWNAND_CE0_B | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_RE_B__RAWNAND_RE_B | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_WE_B__RAWNAND_WE_B | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_WP_B__RAWNAND_WP_B | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+	MX6_PAD_NAND_READY_B__RAWNAND_READY_B | MUX_PAD_CTRL(GPMI_PAD_CTRL2),
+};
+
+static void setup_gpmi_nand(void)
+{
+	struct mxc_ccm_reg *mxc_ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
+
+	/* config gpmi nand iomux */
+	imx_iomux_v3_setup_multiple_pads(nand_pads, ARRAY_SIZE(nand_pads));
+
+	clrbits_le32(&mxc_ccm->CCGR4,
+		     MXC_CCM_CCGR4_RAWNAND_U_BCH_INPUT_APB_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_BCH_INPUT_BCH_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_BCH_INPUT_GPMI_IO_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_INPUT_APB_MASK |
+		     MXC_CCM_CCGR4_PL301_MX6QPER1_BCH_MASK);
+
+	/*
+	 * config gpmi and bch clock to 100 MHz
+	 * bch/gpmi select PLL2 PFD2 400M
+	 * 100M = 400M / 4
+	 */
+	clrbits_le32(&mxc_ccm->cscmr1,
+		     MXC_CCM_CSCMR1_BCH_CLK_SEL |
+		     MXC_CCM_CSCMR1_GPMI_CLK_SEL);
+	clrsetbits_le32(&mxc_ccm->cscdr1,
+			MXC_CCM_CSCDR1_BCH_PODF_MASK |
+			MXC_CCM_CSCDR1_GPMI_PODF_MASK,
+			(3 << MXC_CCM_CSCDR1_BCH_PODF_OFFSET) |
+			(3 << MXC_CCM_CSCDR1_GPMI_PODF_OFFSET));
+
+	/* enable gpmi and bch clock gating */
+	setbits_le32(&mxc_ccm->CCGR4,
+		     MXC_CCM_CCGR4_RAWNAND_U_BCH_INPUT_APB_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_BCH_INPUT_BCH_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_BCH_INPUT_GPMI_IO_MASK |
+		     MXC_CCM_CCGR4_RAWNAND_U_GPMI_INPUT_APB_MASK |
+		     MXC_CCM_CCGR4_PL301_MX6QPER1_BCH_MASK);
+
+	/* enable apbh clock gating */
+	setbits_le32(&mxc_ccm->CCGR0, MXC_CCM_CCGR0_APBHDMA_MASK);
+}
+#endif /* CONFIG_NAND_MXS */
+
 int board_init(void)
 {
 	/* Address of boot parameters */
 	gd->bd->bi_boot_params = PHYS_SDRAM + 0x100;
 
+#ifdef CONFIG_NAND_MXS
+	setup_gpmi_nand();
+#endif
+
 	return 0;
 }