ARM: add tegra20 support to arm720t

Add support for tegra20 arm7 boot processor.  This processor is used
to power on the Cortex A9 and transfer control to it.  In tegra this
processor is an ARM7TDMI not an ARM720T, but since we don't use cache
it was easier to just reuse the ARM720T code as the processors are
otherwise identical except for cache and MMU.

Signed-off-by: Allen Martin <amartin@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Tested-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Tom Warren <twarren@nvidia.com>

10 files changed, 637 insertions, 1 deletions

diff --git a/arch/arm/cpu/arm720t/cpu.c b/arch/arm/cpu/arm720t/cpu.c
index 974f2880a4..ce7b3c9c24 100644
--- a/arch/arm/cpu/arm720t/cpu.c
+++ b/arch/arm/cpu/arm720t/cpu.c
@@ -51,6 +51,8 @@ int cleanup_before_linux (void)
 	/* Nothing more needed */
 #elif defined(CONFIG_INTEGRATOR) && defined(CONFIG_ARCH_INTEGRATOR)
 	/* No cleanup before linux for IntegratorAP/CM720T as yet */
+#elif defined(CONFIG_TEGRA)
+	/* No cleanup before linux for tegra as yet */
 #else
 #error No cleanup_before_linux() defined for this CPU type
 #endif
diff --git a/arch/arm/cpu/arm720t/interrupts.c b/arch/arm/cpu/arm720t/interrupts.c
index 464dd30466..c2f898f2cc 100644
--- a/arch/arm/cpu/arm720t/interrupts.c
+++ b/arch/arm/cpu/arm720t/interrupts.c
@@ -180,6 +180,9 @@ int timer_init (void)
 	PUT32(T0TC, 0);
 	PUT32(T0TCR, 1);	/* enable timer0 */
 
+#elif defined(CONFIG_TEGRA)
+	/* No timer routines for tegra as yet */
+	lastdec = 0;
 #else
 #error No timer_init() defined for this CPU type
 #endif
@@ -282,6 +285,8 @@ void __udelay (unsigned long usec)
 
 #elif defined(CONFIG_INTEGRATOR) && defined(CONFIG_ARCH_INTEGRATOR)
 	/* No timer routines for IntegratorAP/CM720T as yet */
+#elif defined(CONFIG_TEGRA)
+	/* No timer routines for tegra as yet */
 #else
 #error Timer routines not defined for this CPU type
 #endif
diff --git a/arch/arm/cpu/arm720t/start.S b/arch/arm/cpu/arm720t/start.S
index dc047b83a5..2f914e9b4e 100644
--- a/arch/arm/cpu/arm720t/start.S
+++ b/arch/arm/cpu/arm720t/start.S
@@ -59,6 +59,7 @@ _data_abort:		.word _data_abort
 _not_used:		.word _not_used
 _irq:			.word _irq
 _fiq:			.word _fiq
+_pad:			.word 0x12345678 /* now 16*4=64 */
 #else
 _undefined_instruction: .word undefined_instruction
 _software_interrupt:	.word software_interrupt
@@ -67,6 +68,7 @@ _data_abort:		.word data_abort
 _not_used:		.word not_used
 _irq:			.word irq
 _fiq:			.word fiq
+_pad:			.word 0x12345678 /* now 16*4=64 */
 #endif	/* CONFIG_SPL_BUILD */
 
 	.balignl 16,0xdeadbeef
@@ -87,7 +89,11 @@ _fiq:			.word fiq
 
 .globl _TEXT_BASE
 _TEXT_BASE:
+#ifdef CONFIG_SPL_BUILD
+	.word	CONFIG_SPL_TEXT_BASE
+#else
 	.word	CONFIG_SYS_TEXT_BASE
+#endif
 
 /*
  * These are defined in the board-specific linker script.
@@ -409,6 +415,8 @@ lock_loop:
 	ldr	r0, VPBDIV_ADR
 	mov	r1, #0x01	/* VPB clock is same as process clock */
 	str	r1, [r0]
+#elif defined(CONFIG_TEGRA)
+	/* No cpu_init_crit for tegra as yet */
 #else
 #error No cpu_init_crit() defined for current CPU type
 #endif
@@ -424,7 +432,7 @@ lock_loop:
 	str	r1, [r0]
 #endif
 
-#ifndef CONFIG_LPC2292
+#if !defined(CONFIG_LPC2292) && !defined(CONFIG_TEGRA)
 	mov	ip, lr
 	/*
 	 * before relocating, we have to setup RAM timing
@@ -633,6 +641,8 @@ reset_cpu:
 .globl reset_cpu
 reset_cpu:
 	mov	pc, r0
+#elif defined(CONFIG_TEGRA)
+	/* No specific reset actions for tegra as yet */
 #else
 #error No reset_cpu() defined for current CPU type
 #endif
diff --git a/arch/arm/cpu/arm720t/tegra20/Makefile b/arch/arm/cpu/arm720t/tegra20/Makefile
new file mode 100644
index 0000000000..6e484756dd
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/Makefile
@@ -0,0 +1,48 @@
+#
+# (C) Copyright 2010,2011 Nvidia Corporation.
+#
+# (C) Copyright 2000-2008
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# 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
+#
+
+include $(TOPDIR)/config.mk
+
+LIB	= $(obj)lib$(SOC).o
+
+COBJS-y	+= cpu.o
+COBJS-$(CONFIG_SPL_BUILD) += spl.o
+
+SRCS	:= $(COBJS-y:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS-y))
+
+all:	$(obj).depend $(LIB)
+
+$(LIB):	$(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/arch/arm/cpu/arm720t/tegra20/board.h b/arch/arm/cpu/arm720t/tegra20/board.h
new file mode 100644
index 0000000000..61b91c005f
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/board.h
@@ -0,0 +1,25 @@
+/*
+ * (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
+ */
+
+void board_init_uart_f(void);
+void gpio_config_uart(void);
diff --git a/arch/arm/cpu/arm720t/tegra20/config.mk b/arch/arm/cpu/arm720t/tegra20/config.mk
new file mode 100644
index 0000000000..62a31d8a62
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/config.mk
@@ -0,0 +1,26 @@
+#
+# (C) Copyright 2010,2011
+# NVIDIA Corporation <www.nvidia.com>
+#
+# (C) Copyright 2002
+# Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+#
+# 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
+#
+USE_PRIVATE_LIBGCC = yes
diff --git a/arch/arm/cpu/arm720t/tegra20/cpu.c b/arch/arm/cpu/arm720t/tegra20/cpu.c
new file mode 100644
index 0000000000..6d4d66bced
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/cpu.c
@@ -0,0 +1,258 @@
+/*
+* (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
+*/
+
+#include <asm/io.h>
+#include <asm/arch/tegra20.h>
+#include <asm/arch/clk_rst.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pmc.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch/scu.h>
+#include <common.h>
+#include "cpu.h"
+
+/* Returns 1 if the current CPU executing is a Cortex-A9, else 0 */
+int ap20_cpu_is_cortexa9(void)
+{
+	u32 id = readb(NV_PA_PG_UP_BASE + PG_UP_TAG_0);
+	return id == (PG_UP_TAG_0_PID_CPU & 0xff);
+}
+
+void init_pllx(void)
+{
+	struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+	struct clk_pll *pll = &clkrst->crc_pll[CLOCK_ID_XCPU];
+	u32 reg;
+
+	/* If PLLX is already enabled, just return */
+	if (readl(&pll->pll_base) & PLL_ENABLE_MASK)
+		return;
+
+	/* Set PLLX_MISC */
+	writel(1 << PLL_CPCON_SHIFT, &pll->pll_misc);
+
+	/* Use 12MHz clock here */
+	reg = PLL_BYPASS_MASK | (12 << PLL_DIVM_SHIFT);
+	reg |= 1000 << PLL_DIVN_SHIFT;
+	writel(reg, &pll->pll_base);
+
+	reg |= PLL_ENABLE_MASK;
+	writel(reg, &pll->pll_base);
+
+	reg &= ~PLL_BYPASS_MASK;
+	writel(reg, &pll->pll_base);
+}
+
+static void enable_cpu_clock(int enable)
+{
+	struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
+	u32 clk;
+
+	/*
+	 * NOTE:
+	 * Regardless of whether the request is to enable or disable the CPU
+	 * clock, every processor in the CPU complex except the master (CPU 0)
+	 * will have it's clock stopped because the AVP only talks to the
+	 * master. The AVP does not know (nor does it need to know) that there
+	 * are multiple processors in the CPU complex.
+	 */
+
+	if (enable) {
+		/* Initialize PLLX */
+		init_pllx();
+
+		/* Wait until all clocks are stable */
+		udelay(PLL_STABILIZATION_DELAY);
+
+		writel(CCLK_BURST_POLICY, &clkrst->crc_cclk_brst_pol);
+		writel(SUPER_CCLK_DIVIDER, &clkrst->crc_super_cclk_div);
+	}
+
+	/*
+	 * Read the register containing the individual CPU clock enables and
+	 * always stop the clock to CPU 1.
+	 */
+	clk = readl(&clkrst->crc_clk_cpu_cmplx);
+	clk |= 1 << CPU1_CLK_STP_SHIFT;
+
+	/* Stop/Unstop the CPU clock */
+	clk &= ~CPU0_CLK_STP_MASK;
+	clk |= !enable << CPU0_CLK_STP_SHIFT;
+	writel(clk, &clkrst->crc_clk_cpu_cmplx);
+
+	clock_enable(PERIPH_ID_CPU);
+}
+
+static int is_cpu_powered(void)
+{
+	struct pmc_ctlr *pmc = (struct pmc_ctlr *)TEGRA20_PMC_BASE;
+
+	return (readl(&pmc->pmc_pwrgate_status) & CPU_PWRED) ? 1 : 0;
+}
+
+static void remove_cpu_io_clamps(void)
+{
+	struct pmc_ctlr *pmc = (struct pmc_ctlr *)TEGRA20_PMC_BASE;
+	u32 reg;
+
+	/* Remove the clamps on the CPU I/O signals */
+	reg = readl(&pmc->pmc_remove_clamping);
+	reg |= CPU_CLMP;
+	writel(reg, &pmc->pmc_remove_clamping);
+
+	/* Give I/O signals time to stabilize */
+	udelay(IO_STABILIZATION_DELAY);
+}
+
+static void powerup_cpu(void)
+{
+	struct pmc_ctlr *pmc = (struct pmc_ctlr *)TEGRA20_PMC_BASE;
+	u32 reg;
+	int timeout = IO_STABILIZATION_DELAY;
+
+	if (!is_cpu_powered()) {
+		/* Toggle the CPU power state (OFF -> ON) */
+		reg = readl(&pmc->pmc_pwrgate_toggle);
+		reg &= PARTID_CP;
+		reg |= START_CP;
+		writel(reg, &pmc->pmc_pwrgate_toggle);
+
+		/* Wait for the power to come up */
+		while (!is_cpu_powered()) {
+			if (timeout-- == 0)
+				printf("CPU failed to power up!\n");
+			else
+				udelay(10);
+		}
+
+		/*
+		 * Remove the I/O clamps from CPU power partition.
+		 * Recommended only on a Warm boot, if the CPU partition gets
+		 * power gated. Shouldn't cause any harm when called after a
+		 * cold boot according to HW, probably just redundant.
+		 */
+		remove_cpu_io_clamps();
+	}
+}
+
+static void enable_cpu_power_rail(void)
+{
+	struct pmc_ctlr *pmc = (struct pmc_ctlr *)TEGRA20_PMC_BASE;
+	u32 reg;
+
+	reg = readl(&pmc->pmc_cntrl);
+	reg |= CPUPWRREQ_OE;
+	writel(reg, &pmc->pmc_cntrl);
+
+	/*
+	 * The TI PMU65861C needs a 3.75ms delay between enabling
+	 * the power rail and enabling the CPU clock.  This delay
+	 * between SM1EN and SM1 is for switching time + the ramp
+	 * up of the voltage to the CPU (VDD_CPU from PMU).
+	 */
+	udelay(3750);
+}
+
+static void reset_A9_cpu(int reset)
+{
+	/*
+	* NOTE:  Regardless of whether the request is to hold the CPU in reset
+	*        or take it out of reset, every processor in the CPU complex
+	*        except the master (CPU 0) will be held in reset because the
+	*        AVP only talks to the master. The AVP does not know that there
+	*        are multiple processors in the CPU complex.
+	*/
+
+	/* Hold CPU 1 in reset, and CPU 0 if asked */
+	reset_cmplx_set_enable(1, crc_rst_cpu | crc_rst_de | crc_rst_debug, 1);
+	reset_cmplx_set_enable(0, crc_rst_cpu | crc_rst_de | crc_rst_debug,
+			       reset);
+
+	/* Enable/Disable master CPU reset */
+	reset_set_enable(PERIPH_ID_CPU, reset);
+}
+
+static void clock_enable_coresight(int enable)
+{
+	u32 rst, src;
+
+	clock_set_enable(PERIPH_ID_CORESIGHT, enable);
+	reset_set_enable(PERIPH_ID_CORESIGHT, !enable);
+
+	if (enable) {
+		/*
+		 * Put CoreSight on PLLP_OUT0 (216 MHz) and divide it down by
+		 *  1.5, giving an effective frequency of 144MHz.
+		 * Set PLLP_OUT0 [bits31:30 = 00], and use a 7.1 divisor
+		 *  (bits 7:0), so 00000001b == 1.5 (n+1 + .5)
+		 */
+		src = CLK_DIVIDER(NVBL_PLLP_KHZ, 144000);
+		clock_ll_set_source_divisor(PERIPH_ID_CSI, 0, src);
+
+		/* Unlock the CPU CoreSight interfaces */
+		rst = 0xC5ACCE55;
+		writel(rst, CSITE_CPU_DBG0_LAR);
+		writel(rst, CSITE_CPU_DBG1_LAR);
+	}
+}
+
+void start_cpu(u32 reset_vector)
+{
+	/* Enable VDD_CPU */
+	enable_cpu_power_rail();
+
+	/* Hold the CPUs in reset */
+	reset_A9_cpu(1);
+
+	/* Disable the CPU clock */
+	enable_cpu_clock(0);
+
+	/* Enable CoreSight */
+	clock_enable_coresight(1);
+
+	/*
+	 * Set the entry point for CPU execution from reset,
+	 *  if it's a non-zero value.
+	 */
+	if (reset_vector)
+		writel(reset_vector, EXCEP_VECTOR_CPU_RESET_VECTOR);
+
+	/* Enable the CPU clock */
+	enable_cpu_clock(1);
+
+	/* If the CPU doesn't already have power, power it up */
+	powerup_cpu();
+
+	/* Take the CPU out of reset */
+	reset_A9_cpu(0);
+}
+
+
+void halt_avp(void)
+{
+	for (;;) {
+		writel((HALT_COP_EVENT_JTAG | HALT_COP_EVENT_IRQ_1 \
+			| HALT_COP_EVENT_FIQ_1 | (FLOW_MODE_STOP<<29)),
+			FLOW_CTLR_HALT_COP_EVENTS);
+	}
+}
diff --git a/arch/arm/cpu/arm720t/tegra20/cpu.h b/arch/arm/cpu/arm720t/tegra20/cpu.h
new file mode 100644
index 0000000000..6804cd7a3d
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/cpu.h
@@ -0,0 +1,100 @@
+/*
+ * (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
+ */
+#include <asm/types.h>
+
+/* Stabilization delays, in usec */
+#define PLL_STABILIZATION_DELAY (300)
+#define IO_STABILIZATION_DELAY	(1000)
+
+#define NVBL_PLLP_KHZ	(216000)
+
+#define PLLX_ENABLED		(1 << 30)
+#define CCLK_BURST_POLICY	0x20008888
+#define SUPER_CCLK_DIVIDER	0x80000000
+
+/* Calculate clock fractional divider value from ref and target frequencies */
+#define CLK_DIVIDER(REF, FREQ)  ((((REF) * 2) / FREQ) - 2)
+
+/* Calculate clock frequency value from reference and clock divider value */
+#define CLK_FREQUENCY(REF, REG)  (((REF) * 2) / (REG + 2))
+
+/* AVP/CPU ID */
+#define PG_UP_TAG_0_PID_CPU	0x55555555	/* CPU aka "a9" aka "mpcore" */
+#define PG_UP_TAG_0             0x0
+
+#define CORESIGHT_UNLOCK	0xC5ACCE55;
+
+/* AP20-Specific Base Addresses */
+
+/* AP20 Base physical address of SDRAM. */
+#define AP20_BASE_PA_SDRAM      0x00000000
+/* AP20 Base physical address of internal SRAM. */
+#define AP20_BASE_PA_SRAM       0x40000000
+/* AP20 Size of internal SRAM (256KB). */
+#define AP20_BASE_PA_SRAM_SIZE  0x00040000
+/* AP20 Base physical address of flash. */
+#define AP20_BASE_PA_NOR_FLASH  0xD0000000
+/* AP20 Base physical address of boot information table. */
+#define AP20_BASE_PA_BOOT_INFO  AP20_BASE_PA_SRAM
+
+/*
+ * Super-temporary stacks for EXTREMELY early startup. The values chosen for
+ * these addresses must be valid on ALL SOCs because this value is used before
+ * we are able to differentiate between the SOC types.
+ *
+ * NOTE: The since CPU's stack will eventually be moved from IRAM to SDRAM, its
+ *       stack is placed below the AVP stack. Once the CPU stack has been moved,
+ *       the AVP is free to use the IRAM the CPU stack previously occupied if
+ *       it should need to do so.
+ *
+ * NOTE: In multi-processor CPU complex configurations, each processor will have
+ *       its own stack of size CPU_EARLY_BOOT_STACK_SIZE. CPU 0 will have a
+ *       limit of CPU_EARLY_BOOT_STACK_LIMIT. Each successive CPU will have a
+ *       stack limit that is CPU_EARLY_BOOT_STACK_SIZE less then the previous
+ *       CPU.
+ */
+
+/* Common AVP early boot stack limit */
+#define AVP_EARLY_BOOT_STACK_LIMIT	\
+	(AP20_BASE_PA_SRAM + (AP20_BASE_PA_SRAM_SIZE/2))
+/* Common AVP early boot stack size */
+#define AVP_EARLY_BOOT_STACK_SIZE	0x1000
+/* Common CPU early boot stack limit */
+#define CPU_EARLY_BOOT_STACK_LIMIT	\
+	(AVP_EARLY_BOOT_STACK_LIMIT - AVP_EARLY_BOOT_STACK_SIZE)
+/* Common CPU early boot stack size */
+#define CPU_EARLY_BOOT_STACK_SIZE	0x1000
+
+#define EXCEP_VECTOR_CPU_RESET_VECTOR	(NV_PA_EVP_BASE + 0x100)
+#define CSITE_CPU_DBG0_LAR		(NV_PA_CSITE_BASE + 0x10FB0)
+#define CSITE_CPU_DBG1_LAR		(NV_PA_CSITE_BASE + 0x12FB0)
+
+#define FLOW_CTLR_HALT_COP_EVENTS	(NV_PA_FLOW_BASE + 4)
+#define FLOW_MODE_STOP			2
+#define HALT_COP_EVENT_JTAG		(1 << 28)
+#define HALT_COP_EVENT_IRQ_1		(1 << 11)
+#define HALT_COP_EVENT_FIQ_1		(1 << 9)
+
+void start_cpu(u32 reset_vector);
+int ap20_cpu_is_cortexa9(void);
+void halt_avp(void)  __attribute__ ((noreturn));
diff --git a/arch/arm/cpu/arm720t/tegra20/spl.c b/arch/arm/cpu/arm720t/tegra20/spl.c
new file mode 100644
index 0000000000..6c16dce299
--- /dev/null
+++ b/arch/arm/cpu/arm720t/tegra20/spl.c
@@ -0,0 +1,133 @@
+/*
+ * (C) Copyright 2012
+ * NVIDIA Inc, <www.nvidia.com>
+ *
+ * Allen Martin <amartin@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
+ */
+#include <common.h>
+#include <asm/u-boot.h>
+#include <asm/utils.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/arch/clock.h>
+#include <nand.h>
+#include <mmc.h>
+#include <fat.h>
+#include <version.h>
+#include <i2c.h>
+#include <image.h>
+#include <malloc.h>
+#include <linux/compiler.h>
+#include "board.h"
+#include "cpu.h"
+
+#include <asm/io.h>
+#include <asm/arch/tegra20.h>
+#include <asm/arch/clk_rst.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pmc.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch/scu.h>
+#include <common.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Define global data structure pointer to it*/
+static gd_t gdata __attribute__ ((section(".data")));
+static bd_t bdata __attribute__ ((section(".data")));
+
+inline void hang(void)
+{
+	puts("### ERROR ### Please RESET the board ###\n");
+	for (;;)
+		;
+}
+
+void board_init_f(ulong dummy)
+{
+	board_init_uart_f();
+
+	/* Initialize periph GPIOs */
+#ifdef CONFIG_SPI_UART_SWITCH
+	gpio_early_init_uart();
+#else
+	gpio_config_uart();
+#endif
+
+	/*
+	 * We call relocate_code() with relocation target same as the
+	 * CONFIG_SYS_SPL_TEXT_BASE. This will result in relocation getting
+	 * skipped. Instead, only .bss initialization will happen. That's
+	 * all we need
+	 */
+	debug(">>board_init_f()\n");
+	relocate_code(CONFIG_SPL_STACK, &gdata, CONFIG_SPL_TEXT_BASE);
+}
+
+/* This requires UART clocks to be enabled */
+static void preloader_console_init(void)
+{
+	const char *u_boot_rev = U_BOOT_VERSION;
+
+	gd = &gdata;
+	gd->bd = &bdata;
+	gd->flags |= GD_FLG_RELOC;
+	gd->baudrate = CONFIG_BAUDRATE;
+
+	serial_init();		/* serial communications setup */
+
+	gd->have_console = 1;
+
+	/* Avoid a second "U-Boot" coming from this string */
+	u_boot_rev = &u_boot_rev[7];
+
+	printf("\nU-Boot SPL %s (%s - %s)\n", u_boot_rev, U_BOOT_DATE,
+		U_BOOT_TIME);
+}
+
+void board_init_r(gd_t *id, ulong dummy)
+{
+	struct pmux_tri_ctlr *pmt = (struct pmux_tri_ctlr *)NV_PA_APB_MISC_BASE;
+
+	/* enable JTAG */
+	writel(0xC0, &pmt->pmt_cfg_ctl);
+
+	debug(">>spl:board_init_r()\n");
+
+	mem_malloc_init(CONFIG_SYS_SPL_MALLOC_START,
+			CONFIG_SYS_SPL_MALLOC_SIZE);
+
+#ifdef CONFIG_SPL_BOARD_INIT
+	spl_board_init();
+#endif
+
+	clock_early_init();
+	serial_init();
+	preloader_console_init();
+
+	start_cpu((u32)CONFIG_SYS_TEXT_BASE);
+	halt_avp();
+	/* not reached */
+}
+
+int board_usb_init(const void *blob)
+{
+	return 0;
+}
diff --git a/arch/arm/include/asm/arch-tegra20/hardware.h b/arch/arm/include/asm/arch-tegra20/hardware.h
new file mode 100644
index 0000000000..8c47578338
--- /dev/null
+++ b/arch/arm/include/asm/arch-tegra20/hardware.h
@@ -0,0 +1,29 @@
+/*
+* (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 __TEGRA2_HW_H
+#define __TEGRA2_HW_H
+
+/* include tegra specific hardware definitions */
+
+#endif /* __TEGRA2_HW_H */