tegra: Add EMC support for optimal memory timings

Add support for setting up the memory controller parameters. Boards
can set up an appropriate table in the device tree.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/arch/arm/include/asm/arch-tegra2/emc.h b/arch/arm/include/asm/arch-tegra2/emc.h
new file mode 100644
index 0000000..deb3d36
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra2/emc.h
@@ -0,0 +1,113 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2010,2011 NVIDIA Corporation <www.nvidia.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _ARCH_EMC_H_
+#define _ARCH_EMC_H_
+
+#include <asm/types.h>
+
+#define TEGRA_EMC_NUM_REGS	46
+
+/* EMC Registers */
+struct emc_ctlr {
+	u32 cfg;		/* 0x00: EMC_CFG */
+	u32 reserved0[3];	/* 0x04 ~ 0x0C */
+	u32 adr_cfg;		/* 0x10: EMC_ADR_CFG */
+	u32 adr_cfg1;		/* 0x14: EMC_ADR_CFG_1 */
+	u32 reserved1[2];	/* 0x18 ~ 0x18 */
+	u32 refresh_ctrl;	/* 0x20: EMC_REFCTRL */
+	u32 pin;		/* 0x24: EMC_PIN */
+	u32 timing_ctrl;	/* 0x28: EMC_TIMING_CONTROL */
+	u32 rc;			/* 0x2C: EMC_RC */
+	u32 rfc;		/* 0x30: EMC_RFC */
+	u32 ras;		/* 0x34: EMC_RAS */
+	u32 rp;			/* 0x38: EMC_RP */
+	u32 r2w;		/* 0x3C: EMC_R2W */
+	u32 w2r;		/* 0x40: EMC_W2R */
+	u32 r2p;		/* 0x44: EMC_R2P */
+	u32 w2p;		/* 0x48: EMC_W2P */
+	u32 rd_rcd;		/* 0x4C: EMC_RD_RCD */
+	u32 wd_rcd;		/* 0x50: EMC_WD_RCD */
+	u32 rrd;		/* 0x54: EMC_RRD */
+	u32 rext;		/* 0x58: EMC_REXT */
+	u32 wdv;		/* 0x5C: EMC_WDV */
+	u32 quse;		/* 0x60: EMC_QUSE */
+	u32 qrst;		/* 0x64: EMC_QRST */
+	u32 qsafe;		/* 0x68: EMC_QSAFE */
+	u32 rdv;		/* 0x6C: EMC_RDV */
+	u32 refresh;		/* 0x70: EMC_REFRESH */
+	u32 burst_refresh_num;	/* 0x74: EMC_BURST_REFRESH_NUM */
+	u32 pdex2wr;		/* 0x78: EMC_PDEX2WR */
+	u32 pdex2rd;		/* 0x7c: EMC_PDEX2RD */
+	u32 pchg2pden;		/* 0x80: EMC_PCHG2PDEN */
+	u32 act2pden;		/* 0x84: EMC_ACT2PDEN */
+	u32 ar2pden;		/* 0x88: EMC_AR2PDEN */
+	u32 rw2pden;		/* 0x8C: EMC_RW2PDEN */
+	u32 txsr;		/* 0x90: EMC_TXSR */
+	u32 tcke;		/* 0x94: EMC_TCKE */
+	u32 tfaw;		/* 0x98: EMC_TFAW */
+	u32 trpab;		/* 0x9C: EMC_TRPAB */
+	u32 tclkstable;		/* 0xA0: EMC_TCLKSTABLE */
+	u32 tclkstop;		/* 0xA4: EMC_TCLKSTOP */
+	u32 trefbw;		/* 0xA8: EMC_TREFBW */
+	u32 quse_extra;		/* 0xAC: EMC_QUSE_EXTRA */
+	u32 odt_write;		/* 0xB0: EMC_ODT_WRITE */
+	u32 odt_read;		/* 0xB4: EMC_ODT_READ */
+	u32 reserved2[5];	/* 0xB8 ~ 0xC8 */
+	u32 mrs;		/* 0xCC: EMC_MRS */
+	u32 emrs;		/* 0xD0: EMC_EMRS */
+	u32 ref;		/* 0xD4: EMC_REF */
+	u32 pre;		/* 0xD8: EMC_PRE */
+	u32 nop;		/* 0xDC: EMC_NOP */
+	u32 self_ref;		/* 0xE0: EMC_SELF_REF */
+	u32 dpd;		/* 0xE4: EMC_DPD */
+	u32 mrw;		/* 0xE8: EMC_MRW */
+	u32 mrr;		/* 0xEC: EMC_MRR */
+	u32 reserved3;		/* 0xF0: */
+	u32 fbio_cfg1;		/* 0xF4: EMC_FBIO_CFG1 */
+	u32 fbio_dqsib_dly;	/* 0xF8: EMC_FBIO_DQSIB_DLY */
+	u32 fbio_dqsib_dly_msb;	/* 0xFC: EMC_FBIO_DQSIB_DLY_MSG */
+	u32 fbio_spare;		/* 0x100: SBIO_SPARE */
+				/* There are more registers ... */
+};
+
+/**
+ * Set up the EMC for the given rate. The timing parameters are retrieved
+ * from the device tree "nvidia,tegra20-emc" node and its
+ * "nvidia,tegra20-emc-table" sub-nodes.
+ *
+ * @param blob	Device tree blob
+ * @param rate	Clock speed of memory controller in Hz (=2x memory bus rate)
+ * @return 0 if ok, else -ve error code (look in emc.c to decode it)
+ */
+int tegra_set_emc(const void *blob, unsigned rate);
+
+/**
+ * Get a pointer to the EMC controller from the device tree.
+ *
+ * @param blob	Device tree blob
+ * @return pointer to EMC controller
+ */
+struct emc_ctlr *emc_get_controller(const void *blob);
+
+#endif