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-rw-r--r--cpu/arm925t/Makefile43
-rw-r--r--cpu/arm925t/config.mk27
-rw-r--r--cpu/arm925t/cpu.c159
-rw-r--r--cpu/arm925t/interrupts.c301
-rw-r--r--cpu/arm925t/omap925.c73
-rw-r--r--cpu/arm925t/start.S424
6 files changed, 1027 insertions, 0 deletions
diff --git a/cpu/arm925t/Makefile b/cpu/arm925t/Makefile
new file mode 100644
index 0000000..a1db818
--- /dev/null
+++ b/cpu/arm925t/Makefile
@@ -0,0 +1,43 @@
+#
+# (C) Copyright 2000-2003
+# 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 $(TOPDIR)/config.mk
+
+LIB = lib$(CPU).a
+
+START = start.o
+OBJS = interrupts.o cpu.o omap925.o
+
+all: .depend $(START) $(LIB)
+
+$(LIB): $(OBJS)
+ $(AR) crv $@ $(OBJS)
+
+#########################################################################
+
+.depend: Makefile $(START:.o=.S) $(OBJS:.o=.c)
+ $(CC) -M $(CFLAGS) $(START:.o=.S) $(OBJS:.o=.c) > $@
+
+sinclude .depend
+
+#########################################################################
diff --git a/cpu/arm925t/config.mk b/cpu/arm925t/config.mk
new file mode 100644
index 0000000..cef7d26
--- /dev/null
+++ b/cpu/arm925t/config.mk
@@ -0,0 +1,27 @@
+#
+# (C) Copyright 2002
+# Gary Jennejohn, DENX Software Engineering, <gj@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
+#
+
+PLATFORM_RELFLAGS += -fno-strict-aliasing -fno-common -ffixed-r8 \
+ -mshort-load-bytes -msoft-float
+
+PLATFORM_CPPFLAGS += -mapcs-32 -march=armv4
diff --git a/cpu/arm925t/cpu.c b/cpu/arm925t/cpu.c
new file mode 100644
index 0000000..c55fbc7
--- /dev/null
+++ b/cpu/arm925t/cpu.c
@@ -0,0 +1,159 @@
+/*
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <gj@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
+ */
+
+/*
+ * CPU specific code
+ */
+
+#include <common.h>
+#include <command.h>
+#include <arm925t.h>
+
+/* read co-processor 15, register #1 (control register) */
+static unsigned long read_p15_c1 (void)
+{
+ unsigned long value;
+
+ __asm__ __volatile__(
+ "mrc p15, 0, %0, c1, c0, 0 @ read control reg\n"
+ : "=r" (value)
+ :
+ : "memory");
+
+#ifdef MMU_DEBUG
+ printf ("p15/c1 is = %08lx\n", value);
+#endif
+ return value;
+}
+
+/* write to co-processor 15, register #1 (control register) */
+static void write_p15_c1 (unsigned long value)
+{
+#ifdef MMU_DEBUG
+ printf ("write %08lx to p15/c1\n", value);
+#endif
+ __asm__ __volatile__(
+ "mcr p15, 0, %0, c1, c0, 0 @ write it back\n"
+ :
+ : "r" (value)
+ : "memory");
+
+ read_p15_c1 ();
+}
+
+static void cp_delay (void)
+{
+ volatile int i;
+
+ /* Many OMAP regs need at least 2 nops */
+ for (i = 0; i < 100; i++);
+}
+
+/* See also ARM Ref. Man. */
+#define C1_MMU (1<<0) /* mmu off/on */
+#define C1_ALIGN (1<<1) /* alignment faults off/on */
+#define C1_DC (1<<2) /* dcache off/on */
+#define C1_WB (1<<3) /* merging write buffer on/off */
+#define C1_BIG_ENDIAN (1<<7) /* big endian off/on */
+#define C1_SYS_PROT (1<<8) /* system protection */
+#define C1_ROM_PROT (1<<9) /* ROM protection */
+#define C1_IC (1<<12) /* icache off/on */
+#define C1_HIGH_VECTORS (1<<13) /* location of vectors: low/high addresses */
+#define RESERVED_1 (0xf << 3) /* must be 111b for R/W */
+
+int cpu_init (void)
+{
+ /*
+ * setup up stack if necessary
+ */
+#ifdef CONFIG_USE_IRQ
+ IRQ_STACK_START = _armboot_end +
+ CONFIG_STACKSIZE + CONFIG_STACKSIZE_IRQ - 4;
+ FIQ_STACK_START = IRQ_STACK_START + CONFIG_STACKSIZE_FIQ;
+ _armboot_real_end = FIQ_STACK_START + 4;
+#else
+ _armboot_real_end = _armboot_end + CONFIG_STACKSIZE;
+#endif /* CONFIG_USE_IRQ */
+ return (0);
+}
+
+int cleanup_before_linux (void)
+{
+ /*
+ * this function is called just before we call linux
+ * it prepares the processor for linux
+ *
+ * we turn off caches etc ...
+ */
+
+ unsigned long i;
+
+ disable_interrupts ();
+
+ /* turn off I/D-cache */
+ asm ("mrc p15, 0, %0, c1, c0, 0":"=r" (i));
+ i &= ~(C1_DC | C1_IC);
+ asm ("mcr p15, 0, %0, c1, c0, 0": :"r" (i));
+
+ /* flush I/D-cache */
+ i = 0;
+ asm ("mcr p15, 0, %0, c7, c7, 0": :"r" (i));
+ return (0);
+}
+
+int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+ extern void reset_cpu (ulong addr);
+
+ disable_interrupts ();
+ reset_cpu (0);
+ /*NOTREACHED*/
+ return (0);
+}
+
+void icache_enable (void)
+{
+ ulong reg;
+
+ reg = read_p15_c1 (); /* get control reg. */
+ cp_delay ();
+ write_p15_c1 (reg | C1_IC);
+}
+
+void icache_disable (void)
+{
+ ulong reg;
+
+ reg = read_p15_c1 ();
+ cp_delay ();
+ write_p15_c1 (reg & ~C1_IC);
+}
+
+int icache_status (void)
+{
+ return (read_p15_c1 () & C1_IC) != 0;
+}
diff --git a/cpu/arm925t/interrupts.c b/cpu/arm925t/interrupts.c
new file mode 100644
index 0000000..ed8a1c7
--- /dev/null
+++ b/cpu/arm925t/interrupts.c
@@ -0,0 +1,301 @@
+/*
+ * (C) Copyright 2003
+ * Texas Instruments, <www.ti.com>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <gj@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 <common.h>
+#include <arm925t.h>
+#include <configs/omap1510.h>
+
+#include <asm/proc-armv/ptrace.h>
+
+extern void reset_cpu(ulong addr);
+#define TIMER_LOAD_VAL 0xffffffff
+
+/* macro to read the 32 bit timer */
+#define READ_TIMER (*(volatile ulong *)(CFG_TIMERBASE+8))
+
+#ifdef CONFIG_USE_IRQ
+/* enable IRQ interrupts */
+void enable_interrupts (void)
+{
+ unsigned long temp;
+ __asm__ __volatile__("mrs %0, cpsr\n"
+ "bic %0, %0, #0x80\n"
+ "msr cpsr_c, %0"
+ : "=r" (temp)
+ :
+ : "memory");
+}
+
+
+/*
+ * disable IRQ/FIQ interrupts
+ * returns true if interrupts had been enabled before we disabled them
+ */
+int disable_interrupts (void)
+{
+ unsigned long old,temp;
+ __asm__ __volatile__("mrs %0, cpsr\n"
+ "orr %1, %0, #0xc0\n"
+ "msr cpsr_c, %1"
+ : "=r" (old), "=r" (temp)
+ :
+ : "memory");
+ return (old & 0x80) == 0;
+}
+#else
+void enable_interrupts (void)
+{
+ return;
+}
+int disable_interrupts (void)
+{
+ return 0;
+}
+#endif
+
+
+
+void bad_mode (void)
+{
+ panic ("Resetting CPU ...\n");
+ reset_cpu (0);
+}
+
+void show_regs (struct pt_regs *regs)
+{
+ unsigned long flags;
+ const char *processor_modes[] = {
+ "USER_26", "FIQ_26", "IRQ_26", "SVC_26",
+ "UK4_26", "UK5_26", "UK6_26", "UK7_26",
+ "UK8_26", "UK9_26", "UK10_26", "UK11_26",
+ "UK12_26", "UK13_26", "UK14_26", "UK15_26",
+ "USER_32", "FIQ_32", "IRQ_32", "SVC_32",
+ "UK4_32", "UK5_32", "UK6_32", "ABT_32",
+ "UK8_32", "UK9_32", "UK10_32", "UND_32",
+ "UK12_32", "UK13_32", "UK14_32", "SYS_32",
+ };
+
+ flags = condition_codes (regs);
+
+ printf ("pc : [<%08lx>] lr : [<%08lx>]\n"
+ "sp : %08lx ip : %08lx fp : %08lx\n",
+ instruction_pointer (regs),
+ regs->ARM_lr, regs->ARM_sp, regs->ARM_ip, regs->ARM_fp);
+ printf ("r10: %08lx r9 : %08lx r8 : %08lx\n",
+ regs->ARM_r10, regs->ARM_r9, regs->ARM_r8);
+ printf ("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n",
+ regs->ARM_r7, regs->ARM_r6, regs->ARM_r5, regs->ARM_r4);
+ printf ("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n",
+ regs->ARM_r3, regs->ARM_r2, regs->ARM_r1, regs->ARM_r0);
+ printf ("Flags: %c%c%c%c",
+ flags & CC_N_BIT ? 'N' : 'n',
+ flags & CC_Z_BIT ? 'Z' : 'z',
+ flags & CC_C_BIT ? 'C' : 'c', flags & CC_V_BIT ? 'V' : 'v');
+ printf (" IRQs %s FIQs %s Mode %s%s\n",
+ interrupts_enabled (regs) ? "on" : "off",
+ fast_interrupts_enabled (regs) ? "on" : "off",
+ processor_modes[processor_mode (regs)],
+ thumb_mode (regs) ? " (T)" : "");
+}
+
+void do_undefined_instruction (struct pt_regs *pt_regs)
+{
+ printf ("undefined instruction\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_software_interrupt (struct pt_regs *pt_regs)
+{
+ printf ("software interrupt\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_prefetch_abort (struct pt_regs *pt_regs)
+{
+ printf ("prefetch abort\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_data_abort (struct pt_regs *pt_regs)
+{
+ printf ("data abort\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_not_used (struct pt_regs *pt_regs)
+{
+ printf ("not used\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_fiq (struct pt_regs *pt_regs)
+{
+ printf ("fast interrupt request\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+void do_irq (struct pt_regs *pt_regs)
+{
+ printf ("interrupt request\n");
+ show_regs (pt_regs);
+ bad_mode ();
+}
+
+static ulong timestamp;
+static ulong lastdec;
+
+/* nothing really to do with interrupts, just starts up a counter. */
+int interrupt_init (void)
+{
+ int32_t val;
+
+ *((int32_t *) (CFG_TIMERBASE + LOAD_TIM)) = TIMER_LOAD_VAL;
+ val = MPUTIM_ST | MPUTIM_AR | MPUTIM_CLOCK_ENABLE | (CFG_PVT << MPUTIM_PTV_BIT);
+ *((int32_t *) (CFG_TIMERBASE + CNTL_TIMER)) = val;
+ return (0);
+}
+
+/*
+ * timer without interrupts
+ */
+
+void reset_timer (void)
+{
+ reset_timer_masked ();
+}
+
+ulong get_timer (ulong base)
+{
+ return get_timer_masked () - base;
+}
+
+void set_timer (ulong t)
+{
+ timestamp = t;
+}
+
+/* very rough timer... */
+void udelay (unsigned long usec)
+{
+#ifdef CONFIG_INNOVATOROMAP1510
+#define LOOPS_PER_MSEC 60 /* tuned on omap1510 */
+ volatile int i, time_remaining = LOOPS_PER_MSEC * usec;
+
+ for (i = time_remaining; i > 0; i--) {
+ }
+#else
+
+ ulong tmo;
+
+ tmo = usec / 1000;
+ tmo *= CFG_HZ;
+ tmo /= 1000;
+
+ tmo += get_timer (0);
+
+ while (get_timer_masked () < tmo)
+ /*NOP*/;
+#endif
+}
+
+void reset_timer_masked (void)
+{
+ /* reset time */
+ lastdec = READ_TIMER;
+ timestamp = 0;
+}
+
+ulong get_timer_masked (void)
+{
+ ulong now = READ_TIMER; /* current tick value */
+
+ if (lastdec >= now) { /* did I roll (rem decrementer) */
+ /* normal mode */
+ timestamp += lastdec - now; /* record amount of time since last check */
+ } else {
+ /* we have an overflow ... */
+ timestamp += lastdec + TIMER_LOAD_VAL - now;
+ }
+ lastdec = now;
+
+ return timestamp;
+}
+
+void udelay_masked (unsigned long usec)
+{
+#ifdef CONFIG_INNOVATOROMAP1510
+ #define LOOPS_PER_MSEC 60 /* tuned on omap1510 */
+ volatile int i, time_remaining = LOOPS_PER_MSEC*usec;
+ for (i=time_remaining; i>0; i--) { }
+#else
+
+ ulong tmo;
+
+ tmo = usec / 1000;
+ tmo *= CFG_HZ;
+ tmo /= 1000;
+
+ reset_timer_masked ();
+
+ while (get_timer_masked () < tmo)
+ /*NOP*/;
+#endif
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ return get_timer(0);
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk (void)
+{ /* poor timer, may need to improve especiall for bootp. */
+ ulong tbclk;
+
+ tbclk = CFG_HZ;
+ return tbclk;
+}
diff --git a/cpu/arm925t/omap925.c b/cpu/arm925t/omap925.c
new file mode 100644
index 0000000..1166ca6
--- /dev/null
+++ b/cpu/arm925t/omap925.c
@@ -0,0 +1,73 @@
+/*
+ * (C) Copyright 2003
+ * Texas Instruments <www.ti.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 <command.h>
+#include <arm925t.h>
+
+ushort gpioreserved;
+
+void gpioreserve(ushort mask)
+{
+ gpioreserved |= mask;
+}
+
+void gpiosetdir(ushort mask, ushort in)
+{
+ *(ushort *)GPIO_DIR_CONTROL_REG = (*(ushort *)GPIO_DIR_CONTROL_REG & ~mask) | (in & mask);
+}
+
+
+void gpiosetout(ushort mask, ushort out)
+{
+ ushort *r_ptr, r_val;
+
+ r_ptr = (ushort *)GPIO_DATA_OUTPUT_REG; /* set pointer */
+ r_val = *r_ptr & ~mask; /* get previous val, clear bits we want to change */
+ r_val |= (out & mask); /* set specified bits in value + plus origional ones */
+ *r_ptr = r_val; /* write it out */
+/*
+ * gcc screwed this one up :(.
+ *
+ * *(ushort *)GPIO_DATA_OUTPUT_REG = (*(ushort *)GPIO_DATA_OUTPUT_REG & ~mask) | (out & mask);
+ */
+
+}
+
+void gpioinit(void)
+{
+}
+
+
+#define MIF_CONFIG_REG 0xFFFECC0C
+#define FLASH_GLOBAL_CTRL_NWP 1
+
+void archflashwp (void *archdata, int wp)
+{
+ ulong *fgc = (ulong *) MIF_CONFIG_REG;
+
+ if (wp == 1)
+ *fgc &= ~FLASH_GLOBAL_CTRL_NWP;
+ else
+ *fgc |= FLASH_GLOBAL_CTRL_NWP;
+}
diff --git a/cpu/arm925t/start.S b/cpu/arm925t/start.S
new file mode 100644
index 0000000..2115fb3
--- /dev/null
+++ b/cpu/arm925t/start.S
@@ -0,0 +1,424 @@
+/*
+ * armboot - Startup Code for ARM925 CPU-core
+ *
+ * Copyright (c) 2003 Texas Instruments
+ *
+ * ----- Adapted for OMAP1510 from ARM920 code ------
+ *
+ * Copyright (c) 2001 Marius Gröger <mag@sysgo.de>
+ * Copyright (c) 2002 Alex Züpke <azu@sysgo.de>
+ * Copyright (c) 2002 Gary Jennejohn <gj@denx.de>
+ * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com>
+ * Copyright (c) 2003 Kshitij <kshitij@ti.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 <config.h>
+#include <version.h>
+
+#if defined(CONFIG_OMAP1510)
+#include <./configs/omap1510.h>
+#endif
+
+/*
+ *************************************************************************
+ *
+ * Jump vector table as in table 3.1 in [1]
+ *
+ *************************************************************************
+ */
+
+
+.globl _start
+_start: b reset
+ ldr pc, _undefined_instruction
+ ldr pc, _software_interrupt
+ ldr pc, _prefetch_abort
+ ldr pc, _data_abort
+ ldr pc, _not_used
+ ldr pc, _irq
+ ldr pc, _fiq
+
+_undefined_instruction: .word undefined_instruction
+_software_interrupt: .word software_interrupt
+_prefetch_abort: .word prefetch_abort
+_data_abort: .word data_abort
+_not_used: .word not_used
+_irq: .word irq
+_fiq: .word fiq
+
+ .balignl 16,0xdeadbeef
+
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * setup Memory and board specific bits prior to relocation.
+ * relocate armboot to ram
+ * setup stack
+ *
+ *************************************************************************
+ */
+
+/*
+ * CFG_MEM_END is in the board dependent config-file (configs/config_BOARD.h)
+ */
+_TEXT_BASE:
+ .word TEXT_BASE
+
+.globl _armboot_start
+_armboot_start:
+ .word _start
+
+/*
+ * Note: _armboot_end_data and _armboot_end are defined
+ * by the (board-dependent) linker script.
+ * _armboot_end_data is the first usable FLASH address after armboot
+ */
+.globl _armboot_end_data
+_armboot_end_data:
+ .word armboot_end_data
+.globl _armboot_end
+_armboot_end:
+ .word armboot_end
+
+/*
+ * _armboot_real_end is the first usable RAM address behind armboot
+ * and the various stacks
+ */
+.globl _armboot_real_end
+_armboot_real_end:
+ .word 0x0badc0de
+
+#ifdef CONFIG_USE_IRQ
+/* IRQ stack memory (calculated at run-time) */
+.globl IRQ_STACK_START
+IRQ_STACK_START:
+ .word 0x0badc0de
+
+/* IRQ stack memory (calculated at run-time) */
+.globl FIQ_STACK_START
+FIQ_STACK_START:
+ .word 0x0badc0de
+#endif
+
+
+/*
+ * the actual reset code
+ */
+
+reset:
+ /*
+ * set the cpu to SVC32 mode
+ */
+ mrs r0,cpsr
+ bic r0,r0,#0x1f
+ orr r0,r0,#0xd3
+ msr cpsr,r0
+
+ /*
+ * Set up 925T mode
+ */
+ mov r1, #0x81 /* Set ARM925T configuration. */
+ mcr p15, 0, r1, c15, c1, 0 /* Write ARM925T configuration register. */
+
+ /*
+ * turn off the watchdog, unlock/diable sequence
+ */
+ mov r1, #0xF5
+ ldr r0, =WDTIM_MODE
+ strh r1, [r0]
+ mov r1, #0xA0
+ strh r1, [r0]
+
+ /*
+ * mask all IRQs by setting all bits in the INTMR - default
+ */
+ mov r1, #0xffffffff
+ ldr r0, =REG_IHL1_MIR
+ str r1, [r0]
+ ldr r0, =REG_IHL2_MIR
+ str r1, [r0]
+
+ /*
+ * wait for dpll to lock
+ */
+ ldr r0, =CK_DPLL1
+ mov r1, #0x10
+ strh r1, [r0]
+poll1:
+ ldrh r1, [r0]
+ ands r1, r1, #0x01
+ beq poll1
+ bl cpu_init_crit
+
+relocate:
+ /*
+ * relocate armboot to RAM
+ */
+ adr r0, _start /* r0 <- current position of code */
+ ldr r2, _armboot_start
+ ldr r3, _armboot_end
+ sub r2, r3, r2 /* r2 <- size of armboot */
+ ldr r1, _TEXT_BASE /* r1 <- destination address */
+ add r2, r0, r2 /* r2 <- source end address */
+
+ /*
+ * r0 = source address
+ * r1 = target address
+ * r2 = source end address
+ */
+copy_loop:
+ ldmia r0!, {r3-r10}
+ stmia r1!, {r3-r10}
+ cmp r0, r2
+ ble copy_loop
+
+ /* set up the stack */
+ ldr r0, _armboot_end
+ add r0, r0, #CONFIG_STACKSIZE
+ sub sp, r0, #12 /* leave 3 words for abort-stack */
+
+ ldr pc, _start_armboot
+
+_start_armboot: .word start_armboot
+
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+
+
+cpu_init_crit:
+ /*
+ * flush v4 I/D caches
+ */
+ mov r0, #0
+ mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */
+ mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
+
+ /*
+ * disable MMU stuff and caches
+ */
+ mrc p15, 0, r0, c1, c0, 0
+ bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS)
+ bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM)
+ orr r0, r0, #0x00000002 @ set bit 2 (A) Align
+ orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache
+ mcr p15, 0, r0, c1, c0, 0
+
+ /*
+ * Go setup Memory and board specific bits prior to relocation.
+ */
+ mov ip, lr /* perserve link reg across call */
+ bl platformsetup /* go setup pll,mux,memory */
+ mov lr, ip /* restore link */
+ mov pc, lr /* back to my caller */
+/*
+ *************************************************************************
+ *
+ * Interrupt handling
+ *
+ *************************************************************************
+ */
+
+@
+@ IRQ stack frame.
+@
+#define S_FRAME_SIZE 72
+
+#define S_OLD_R0 68
+#define S_PSR 64
+#define S_PC 60
+#define S_LR 56
+#define S_SP 52
+
+#define S_IP 48
+#define S_FP 44
+#define S_R10 40
+#define S_R9 36
+#define S_R8 32
+#define S_R7 28
+#define S_R6 24
+#define S_R5 20
+#define S_R4 16
+#define S_R3 12
+#define S_R2 8
+#define S_R1 4
+#define S_R0 0
+
+#define MODE_SVC 0x13
+#define I_BIT 0x80
+
+/*
+ * use bad_save_user_regs for abort/prefetch/undef/swi ...
+ * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling
+ */
+
+ .macro bad_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE @ carve out a frame on current user stack
+ stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12
+
+ ldr r2, _armboot_end @ find top of stack
+ add r2, r2, #CONFIG_STACKSIZE @ find base of normal stack
+ sub r2, r2, #8 @ set base 2 words into abort stack
+ ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs)
+ add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack
+
+ add r5, sp, #S_SP
+ mov r1, lr
+ stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr
+ mov r0, sp @ save current stack into r0 (param register)
+ .endm
+
+ .macro irq_save_user_regs
+ sub sp, sp, #S_FRAME_SIZE
+ stmia sp, {r0 - r12} @ Calling r0-r12
+ add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good.
+ stmdb r8, {sp, lr}^ @ Calling SP, LR
+ str lr, [r8, #0] @ Save calling PC
+ mrs r6, spsr
+ str r6, [r8, #4] @ Save CPSR
+ str r0, [r8, #8] @ Save OLD_R0
+ mov r0, sp
+ .endm
+
+ .macro irq_restore_user_regs
+ ldmia sp, {r0 - lr}^ @ Calling r0 - lr
+ mov r0, r0
+ ldr lr, [sp, #S_PC] @ Get PC
+ add sp, sp, #S_FRAME_SIZE
+ subs pc, lr, #4 @ return & move spsr_svc into cpsr
+ .endm
+
+ .macro get_bad_stack
+ ldr r13, _armboot_end @ get bottom of stack (into sp by by user stack pointer).
+ add r13, r13, #CONFIG_STACKSIZE @ head to reserved words at the top of the stack
+ sub r13, r13, #8 @ reserved a couple spots in abort stack
+
+ str lr, [r13] @ save caller lr in position 0 of saved stack
+ mrs lr, spsr @ get the spsr
+ str lr, [r13, #4] @ save spsr in position 1 of saved stack
+
+ mov r13, #MODE_SVC @ prepare SVC-Mode
+ @ msr spsr_c, r13
+ msr spsr, r13 @ switch modes, make sure moves will execute
+ mov lr, pc @ capture return pc
+ movs pc, lr @ jump to next instruction & switch modes.
+ .endm
+
+ .macro get_irq_stack @ setup IRQ stack
+ ldr sp, IRQ_STACK_START
+ .endm
+
+ .macro get_fiq_stack @ setup FIQ stack
+ ldr sp, FIQ_STACK_START
+ .endm
+
+/*
+ * exception handlers
+ */
+ .align 5
+undefined_instruction:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_undefined_instruction
+
+ .align 5
+software_interrupt:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_software_interrupt
+
+ .align 5
+prefetch_abort:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_prefetch_abort
+
+ .align 5
+data_abort:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_data_abort
+
+ .align 5
+not_used:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_not_used
+
+#ifdef CONFIG_USE_IRQ
+
+ .align 5
+irq:
+ get_irq_stack
+ irq_save_user_regs
+ bl do_irq
+ irq_restore_user_regs
+
+ .align 5
+fiq:
+ get_fiq_stack
+ /* someone ought to write a more effiction fiq_save_user_regs */
+ irq_save_user_regs
+ bl do_fiq
+ irq_restore_user_regs
+
+#else
+
+ .align 5
+irq:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_irq
+
+ .align 5
+fiq:
+ get_bad_stack
+ bad_save_user_regs
+ bl do_fiq
+
+#endif
+
+ .align 5
+.globl reset_cpu
+reset_cpu:
+ ldr r1, rstctl1 /* get clkm1 reset ctl */
+ mov r3, #0x0
+ strh r3, [r1] /* clear it */
+ mov r3, #0x8
+ strh r3, [r1] /* force dsp+arm reset */
+_loop_forever:
+ b _loop_forever
+rstctl1:
+ .word 0xfffece10