Patches by Scott McNutt, 24 Aug 2004:
- Add support for Altera Nios-II processors.
- Add support for Psyent PCI-5441 board.
- Add support for Psyent PK1C20 board.
diff --git a/cpu/nios2/Makefile b/cpu/nios2/Makefile
new file mode 100644
index 0000000..76b324a
--- /dev/null
+++ b/cpu/nios2/Makefile
@@ -0,0 +1,44 @@
+#
+# (C) Copyright 2000
+# 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
+AOBJS = exceptions.o
+OBJS = cpu.o interrupts.o serial.o traps.o
+
+all: .depend $(START) $(LIB)
+
+$(LIB): $(OBJS) $(AOBJS)
+ $(AR) crv $@ $(OBJS) $(AOBJS)
+
+#########################################################################
+
+.depend: Makefile $(START:.o=.S) $(OBJS:.o=.c) $(AOBJS:.o=.S)
+ $(CC) -M $(CFLAGS) $(START:.o=.S) $(OBJS:.o=.c) $(AOBJS:.o=.S) > $@
+
+sinclude .depend
+
+#########################################################################
diff --git a/cpu/nios2/config.mk b/cpu/nios2/config.mk
new file mode 100644
index 0000000..f228d72
--- /dev/null
+++ b/cpu/nios2/config.mk
@@ -0,0 +1,24 @@
+#
+# (C) Copyright 2000
+# 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
+#
+
+PLATFORM_RELFLAGS +=
diff --git a/cpu/nios2/cpu.c b/cpu/nios2/cpu.c
new file mode 100644
index 0000000..c9db127
--- /dev/null
+++ b/cpu/nios2/cpu.c
@@ -0,0 +1,62 @@
+/*
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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 <nios2.h>
+#include <nios2-io.h>
+
+#if defined (CFG_NIOS_SYSID_BASE)
+#include <linux/time.h>
+static void check_sysid (void)
+{
+ struct nios_sysid_t *sysid =
+ (struct nios_sysid_t *)CACHE_BYPASS(CFG_NIOS_SYSID_BASE);
+ struct tm t;
+ char asc[32];
+
+ localtime_r ((time_t *)&sysid->timestamp, &t);
+ asctime_r (&t, asc);
+ printf ("SYSID : %08x, %s", sysid->id, asc);
+
+}
+#endif /* CFG_NIOS_SYSID_BASE */
+
+int checkcpu (void)
+{
+ printf ("CPU : Nios-II\n");
+#if !defined(CFG_NIOS_SYSID_BASE)
+ printf ("SYSID : <unknown>\n");
+#else
+ check_sysid ();
+#endif
+ return (0);
+}
+
+
+int do_reset (void)
+{
+ void (*rst)(void) = (void(*)(void))CFG_RESET_ADDR;
+ disable_interrupts ();
+ rst();
+ return(0);
+}
diff --git a/cpu/nios2/exceptions.S b/cpu/nios2/exceptions.S
new file mode 100644
index 0000000..d3b95cf
--- /dev/null
+++ b/cpu/nios2/exceptions.S
@@ -0,0 +1,152 @@
+/*
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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 <asm/opcodes.h>
+
+
+ .text
+ .align 4
+
+ .global _exception
+
+_exception:
+ /* SAVE ALL REGS -- this allows trap and unimplemented
+ * instruction handlers to be coded conveniently in C
+ */
+ addi sp, sp, -(33*4)
+ stw r0, 0(sp)
+ stw r1, 4(sp)
+ stw r2, 8(sp)
+ stw r3, 12(sp)
+ stw r4, 16(sp)
+ stw r5, 20(sp)
+ stw r6, 24(sp)
+ stw r7, 28(sp)
+ stw r8, 32(sp)
+ stw r9, 36(sp)
+ stw r10, 40(sp)
+ stw r11, 44(sp)
+ stw r12, 48(sp)
+ stw r13, 52(sp)
+ stw r14, 56(sp)
+ stw r15, 60(sp)
+ stw r16, 64(sp)
+ stw r17, 68(sp)
+ stw r19, 72(sp)
+ stw r19, 76(sp)
+ stw r20, 80(sp)
+ stw r21, 84(sp)
+ stw r22, 88(sp)
+ stw r23, 92(sp)
+ stw r24, 96(sp)
+ stw r25, 100(sp)
+ stw r26, 104(sp)
+ stw r27, 108(sp)
+ stw r28, 112(sp)
+ stw r29, 116(sp)
+ stw r30, 120(sp)
+ stw r31, 124(sp)
+ rdctl et, estatus
+ stw et, 128(sp)
+
+ /* If interrupts are disabled -- software interrupt */
+ rdctl et, estatus
+ andi et, et, 1
+ beq et, r0, 0f
+
+ /* If no interrupts are pending -- software interrupt */
+ rdctl et, ipending
+ beq et, r0, 0f
+
+ /* HARDWARE INTERRUPT: Call interrupt handler */
+ movhi r3, %hi(external_interrupt)
+ ori r3, r3, %lo(external_interrupt)
+ mov r4, sp /* ptr to regs */
+ callr r3
+
+ /* Return address fixup: execution resumes by re-issue of
+ * interrupted instruction at ea-4 (ea == r29). Here we do
+ * simple fixup to allow common exception return.
+ */
+ ldw r3, 116(sp)
+ addi r3, r3, -4
+ stw r3, 116(sp)
+ br _exception_return
+
+0:
+ /* TRAP EXCEPTION */
+ movhi r3, %hi(OPC_TRAP)
+ ori r3, r3, %lo(OPC_TRAP)
+ addi r1, ea, -4
+ ldw r1, 0(r1)
+ bne r1, r3, 1f
+ movhi r3, %hi(trap_handler)
+ ori r3, r3, %lo(trap_handler)
+ mov r4, sp /* ptr to regs */
+ callr r3
+ br _exception_return
+
+1:
+ /* UNIMPLEMENTED INSTRUCTION EXCEPTION */
+ movhi r3, %hi(soft_emulation)
+ ori r3, r3, %lo(soft_emulation)
+ mov r4, sp /* ptr to regs */
+ callr r3
+
+ /* Restore regsisters and return from exception*/
+_exception_return:
+ ldw r1, 4(sp)
+ ldw r2, 8(sp)
+ ldw r3, 12(sp)
+ ldw r4, 16(sp)
+ ldw r5, 20(sp)
+ ldw r6, 24(sp)
+ ldw r7, 28(sp)
+ ldw r8, 32(sp)
+ ldw r9, 36(sp)
+ ldw r10, 40(sp)
+ ldw r11, 44(sp)
+ ldw r12, 48(sp)
+ ldw r13, 52(sp)
+ ldw r14, 56(sp)
+ ldw r15, 60(sp)
+ ldw r16, 64(sp)
+ ldw r17, 68(sp)
+ ldw r19, 72(sp)
+ ldw r19, 76(sp)
+ ldw r20, 80(sp)
+ ldw r21, 84(sp)
+ ldw r22, 88(sp)
+ ldw r23, 92(sp)
+ ldw r24, 96(sp)
+ ldw r25, 100(sp)
+ ldw r26, 104(sp)
+ ldw r27, 108(sp)
+ ldw r28, 112(sp)
+ ldw r29, 116(sp)
+ ldw r30, 120(sp)
+ ldw r31, 124(sp)
+ addi sp, sp, (33*4)
+ eret
+/*-------------------------------------------------------------*/
diff --git a/cpu/nios2/interrupts.c b/cpu/nios2/interrupts.c
new file mode 100644
index 0000000..4a6da58
--- /dev/null
+++ b/cpu/nios2/interrupts.c
@@ -0,0 +1,229 @@
+/*
+ * (C) Copyright 2000-2002
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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 <nios2.h>
+#include <nios2-io.h>
+#include <asm/ptrace.h>
+#include <common.h>
+#include <command.h>
+#include <watchdog.h>
+#ifdef CONFIG_STATUS_LED
+#include <status_led.h>
+#endif
+
+#if defined(CFG_NIOS_TMRBASE) && !defined(CFG_NIOS_TMRIRQ)
+#error CFG_NIOS_TMRIRQ not defined (see documentation)
+#endif
+
+/****************************************************************************/
+
+struct irq_action {
+ interrupt_handler_t *handler;
+ void *arg;
+ int count;
+};
+
+static struct irq_action vecs[32];
+
+/*************************************************************************/
+volatile ulong timestamp = 0;
+
+void reset_timer (void)
+{
+ timestamp = 0;
+}
+
+ulong get_timer (ulong base)
+{
+ WATCHDOG_RESET ();
+ return (timestamp - base);
+}
+
+void set_timer (ulong t)
+{
+ timestamp = t;
+}
+
+
+/* The board must handle this interrupt if a timer is not
+ * provided.
+ */
+#if defined(CFG_NIOS_TMRBASE)
+void tmr_isr (void *arg)
+{
+ nios_timer_t *tmr = (nios_timer_t *)arg;
+ /* Interrupt is cleared by writing anything to the
+ * status register.
+ */
+ tmr->status = 0;
+ timestamp += CFG_NIOS_TMRMS;
+#ifdef CONFIG_STATUS_LED
+ status_led_tick(timestamp);
+#endif
+}
+
+static void tmr_init (void)
+{
+ nios_timer_t *tmr =(nios_timer_t *)CACHE_BYPASS(CFG_NIOS_TMRBASE);
+
+ tmr->control &= ~(NIOS_TIMER_START | NIOS_TIMER_ITO);
+ tmr->control |= NIOS_TIMER_STOP;
+#if defined(CFG_NIOS_TMRCNT)
+ tmr->periodl = CFG_NIOS_TMRCNT & 0xffff;
+ tmr->periodh = (CFG_NIOS_TMRCNT >> 16) & 0xffff;
+#endif
+ tmr->control |= ( NIOS_TIMER_ITO |
+ NIOS_TIMER_CONT |
+ NIOS_TIMER_START );
+ irq_install_handler (CFG_NIOS_TMRIRQ, tmr_isr, (void *)tmr);
+}
+
+#endif /* CFG_NIOS_TMRBASE */
+
+/*************************************************************************/
+int disable_interrupts (void)
+{
+ int val = rdctl (CTL_STATUS);
+ wrctl (CTL_STATUS, val & ~STATUS_IE);
+ return (val & STATUS_IE);
+}
+
+void enable_interrupts( void )
+{
+ int val = rdctl (CTL_STATUS);
+ wrctl (CTL_STATUS, val | STATUS_IE);
+}
+
+void external_interrupt (struct pt_regs *regs)
+{
+ unsigned irqs;
+ struct irq_action *act;
+
+ /* Evaluate only irqs that are both enabled AND pending */
+ irqs = rdctl (CTL_IENABLE) & rdctl (CTL_IPENDING);
+ act = vecs;
+
+ /* Assume (as does the Nios2 HAL) that bit 0 is highest
+ * priority. NOTE: There is ALWAYS a handler assigned
+ * (the default if no other).
+ */
+ while (irqs) {
+ if (irqs & 1) {
+ act->handler (act->arg);
+ act->count++;
+ }
+ irqs >>=1;
+ act++;
+ }
+}
+
+static void def_hdlr (void *arg)
+{
+ unsigned irqs = rdctl (CTL_IENABLE);
+
+ /* Disable the individual interrupt -- with gratuitous
+ * warning.
+ */
+ irqs &= ~(1 << (int)arg);
+ wrctl (CTL_IENABLE, irqs);
+ printf ("WARNING: Disabling unhandled interrupt: %d\n",
+ (int)arg);
+}
+
+/*************************************************************************/
+void irq_install_handler (int irq, interrupt_handler_t *hdlr, void *arg)
+{
+
+ int flag;
+ struct irq_action *act;
+ unsigned ena = rdctl (CTL_IENABLE);
+
+ if ((irq < 0) || (irq > 31))
+ return;
+ act = &vecs[irq];
+
+ flag = disable_interrupts ();
+ if (hdlr) {
+ act->handler = hdlr;
+ act->arg = arg;
+ ena |= (1 << irq); /* enable */
+ } else {
+ act->handler = def_hdlr;
+ act->arg = (void *)irq;
+ ena &= ~(1 << irq); /* disable */
+ }
+ wrctl (CTL_IENABLE, ena);
+ if (flag) enable_interrupts ();
+}
+
+
+int interrupt_init (void)
+{
+ int i;
+
+ /* Assign the default handler to all */
+ for (i = 0; i < 32; i++) {
+ vecs[i].handler = def_hdlr;
+ vecs[i].arg = (void *)i;
+ vecs[i].count = 0;
+ }
+
+#if defined(CFG_NIOS_TMRBASE)
+ tmr_init ();
+#endif
+
+ enable_interrupts ();
+ return (0);
+}
+
+
+/*************************************************************************/
+#if (CONFIG_COMMANDS & CFG_CMD_IRQ)
+int do_irqinfo (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
+{
+ int i;
+ struct irq_action *act = vecs;
+
+ printf ("\nInterrupt-Information:\n\n");
+ printf ("Nr Routine Arg Count\n");
+ printf ("-----------------------------\n");
+
+ for (i=0; i<32; i++) {
+ if (act->handler != def_hdlr) {
+ printf ("%02d %08lx %08lx %d\n",
+ i,
+ (ulong)act->handler,
+ (ulong)act->arg,
+ act->count);
+ }
+ act++;
+ }
+ printf ("\n");
+
+ return (0);
+}
+#endif /* CONFIG_COMMANDS & CFG_CMD_IRQ */
diff --git a/cpu/nios2/serial.c b/cpu/nios2/serial.c
new file mode 100644
index 0000000..2d08c93
--- /dev/null
+++ b/cpu/nios2/serial.c
@@ -0,0 +1,144 @@
+/*
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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 <watchdog.h>
+#include <nios2.h>
+#include <nios2-io.h>
+
+/*------------------------------------------------------------------
+ * JTAG acts as the serial port
+ *-----------------------------------------------------------------*/
+#if defined(CONFIG_CONSOLE_JTAG)
+
+static nios_jtag_t *jtag =
+ (nios_jtag_t *)CACHE_BYPASS(CFG_NIOS_CONSOLE);
+
+void serial_setbrg( void ){ return; }
+int serial_init( void ) { return(0);}
+
+void serial_putc (char c)
+{
+ unsigned val;
+
+ while (NIOS_JTAG_WSPACE (jtag->control) == 0)
+ WATCHDOG_RESET ();
+ jtag->data = (unsigned char)c;
+}
+
+void serial_puts (const char *s)
+{
+ while (*s != 0)
+ serial_putc (*s++);
+}
+
+int serial_tstc (void)
+{
+ return (jtag->control & NIOS_JTAG_RRDY);
+}
+
+int serial_getc (void)
+{
+ int c;
+ unsigned val;
+
+ while (1) {
+ WATCHDOG_RESET ();
+ val = jtag->data;
+ if (val & NIOS_JTAG_RVALID)
+ break;
+ }
+ c = val & 0x0ff;
+ return (c);
+}
+
+/*------------------------------------------------------------------
+ * UART the serial port
+ *-----------------------------------------------------------------*/
+#else
+
+static nios_uart_t *uart = (nios_uart_t *)
+ CACHE_BYPASS(CFG_NIOS_CONSOLE);
+
+#if defined(CFG_NIOS_FIXEDBAUD)
+
+/* Everything's already setup for fixed-baud PTF
+ * assignment
+ */
+void serial_setbrg (void){ return; }
+int serial_init (void) { return (0);}
+
+#else
+
+void serial_setbrg (void)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ unsigned div;
+
+ div = (CONFIG_SYS_CLK_FREQ/gd->baudrate)-1;
+ uart->divisor = div;
+ return;
+}
+
+int serial_init (void)
+{
+ serial_setbrg ();
+ return (0);
+}
+
+#endif /* CFG_NIOS_FIXEDBAUD */
+
+
+/*-----------------------------------------------------------------------
+ * UART CONSOLE
+ *---------------------------------------------------------------------*/
+void serial_putc (char c)
+{
+ if (c == '\n')
+ serial_putc ('\r');
+ while ((uart->status & NIOS_UART_TRDY) == 0)
+ WATCHDOG_RESET ();
+ uart->txdata = (unsigned char)c;
+}
+
+void serial_puts (const char *s)
+{
+ while (*s != 0) {
+ serial_putc (*s++);
+ }
+}
+
+int serial_tstc (void)
+{
+ return (uart->status & NIOS_UART_RRDY);
+}
+
+int serial_getc (void)
+{
+ while (serial_tstc () == 0)
+ WATCHDOG_RESET ();
+ return( uart->rxdata & 0x00ff );
+}
+
+#endif /* CONFIG_JTAG_CONSOLE */
diff --git a/cpu/nios2/start.S b/cpu/nios2/start.S
new file mode 100644
index 0000000..281d42c
--- /dev/null
+++ b/cpu/nios2/start.S
@@ -0,0 +1,211 @@
+/*
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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>
+
+/*************************************************************************
+ * RESTART
+ ************************************************************************/
+
+ .text
+ .global _start
+
+_start:
+ /* ICACHE INIT -- only the icache line at the reset address
+ * is invalidated at reset. So the init must stay within
+ * the cache line size (8 words). If GERMS is used, we'll
+ * just be invalidating the cache a second time. If cache
+ * is not implemented initi behaves as nop.
+ */
+ movhi r4, %hi(CFG_ICACHELINE_SIZE)
+ ori r4, r4, %lo(CFG_ICACHELINE_SIZE)
+ movhi r5, %hi(CFG_ICACHE_SIZE)
+ ori r5, r5, %lo(CFG_ICACHE_SIZE)
+ mov r6, r0
+0: initi r6
+ add r6, r6, r4
+ bltu r6, r5, 0b
+
+ /* INTERRUPTS -- for now, all interrupts masked and globally
+ * disabled.
+ */
+ wrctl status, r0 /* Disable interrupts */
+ wrctl ienable, r0 /* All disabled */
+
+ /* DCACHE INIT -- if dcache not implemented, initd behaves as
+ * nop.
+ */
+ movhi r4, %hi(CFG_DCACHELINE_SIZE)
+ ori r4, r4, %lo(CFG_DCACHELINE_SIZE)
+ movhi r5, %hi(CFG_DCACHE_SIZE)
+ ori r5, r5, %lo(CFG_DCACHE_SIZE)
+ mov r6, r0
+1: initd 0(r6)
+ add r6, r6, r4
+ bltu r6, r5, 1b
+
+ /* RELOCATE CODE, DATA & COMMAND TABLE -- the following code
+ * assumes code, data and the command table are all
+ * contiguous. This lets us relocate everything as a single
+ * block. Make sure the linker script matches this ;-)
+ */
+ nextpc r4
+_cur: movhi r5, %hi(_cur - _start)
+ ori r5, r5, %lo(_cur - _start)
+ sub r4, r4, r5 /* r4 <- cur _start */
+ mov r8, r4
+ movhi r5, %hi(_start)
+ ori r5, r5, %lo(_start) /* r5 <- linked _start */
+ beq r4, r5, 3f
+
+ movhi r6, %hi(_edata)
+ ori r6, r6, %lo(_edata)
+2: ldwio r7, 0(r4)
+ addi r4, r4, 4
+ stwio r7, 0(r5)
+ addi r5, r5, 4
+ bne r5, r6, 2b
+3:
+
+ /* ZERO BSS/SBSS -- bss and sbss are assumed to be adjacent
+ * and between __bss_start and _end.
+ */
+ movhi r5, %hi(__bss_start)
+ ori r5, r5, %lo(__bss_start)
+ movhi r6, %hi(_end)
+ ori r6, r6, %lo(_end)
+ beq r5, r6, 5f
+
+4: stwio r0, 0(r5)
+ addi r5, r5, 4
+ bne r5, r6, 4b
+5:
+
+ /* GLOBAL POINTER -- the global pointer is used to reference
+ * "small data" (see -G switch). The linker script must
+ * provide the gp address.
+ */
+ movhi gp, %hi(_gp)
+ ori gp, gp, %lo(_gp)
+
+ /* JUMP TO RELOC ADDR */
+ movhi r4, %hi(_reloc)
+ ori r4, r4, %lo(_reloc)
+ jmp r4
+_reloc:
+
+ /* COPY EXCEPTION TRAMPOLINE -- copy the tramp to the
+ * exception address.
+ */
+#if !defined(CONFIG_ROM_STUBS)
+ movhi r4, %hi(_except_start)
+ ori r4, r4, %lo(_except_start)
+ movhi r5, %hi(_except_end)
+ ori r5, r5, %lo(_except_end)
+ movhi r6, %hi(CFG_EXCEPTION_ADDR)
+ ori r6, r6, %lo(CFG_EXCEPTION_ADDR)
+
+6: ldwio r7, 0(r4)
+ stwio r7, 0(r6)
+ addi r4, r4, 4
+ addi r6, r6, 4
+ bne r4, r5, 6b
+#endif
+
+ /* STACK INIT -- zero top two words for call back chain.
+ */
+ movhi sp, %hi(CFG_INIT_SP)
+ ori sp, sp, %lo(CFG_INIT_SP)
+ addi sp, sp, -8
+ stw r0, 0(sp)
+ stw r0, 4(sp)
+ mov fp, sp
+
+ /*
+ * Call board_init -- never returns
+ */
+ movhi r4, %hi(board_init@h)
+ ori r4, r4, %lo(board_init@h)
+ callr r4
+
+ /* NEVER RETURNS -- but branch to the _start just
+ * in case ;-)
+ */
+ br _start
+
+ /* EXCEPTION TRAMPOLINE -- the following gets copied
+ * to the exception address.
+ */
+_except_start:
+ movhi et, %hi(_exception)
+ ori et, et, %lo(_exception)
+ jmp et
+_except_end:
+
+
+/*
+ * dly_clks -- Nios2 (like Nios1) doesn't have a timebase in
+ * the core. For simple delay loops, we do our best by counting
+ * instruction cycles.
+ *
+ * Instruction performance varies based on the core. For cores
+ * with icache and static/dynamic branch prediction (II/f, II/s):
+ *
+ * Normal ALU (e.g. add, cmp, etc): 1 cycle
+ * Branch (correctly predicted, taken): 2 cycles
+ * Negative offset is predicted (II/s).
+ *
+ * For cores without icache and no branch prediction (II/e):
+ *
+ * Normal ALU (e.g. add, cmp, etc): 6 cycles
+ * Branch (no prediction): 6 cycles
+ *
+ * For simplicity, if an instruction cache is implemented we
+ * assume II/f or II/s. Otherwise, we use the II/e.
+ *
+ */
+ .globl dly_clks
+
+dly_clks:
+
+#if (CFG_ICACHE_SIZE > 0)
+ subi r4, r4, 3 /* 3 clocks/loop */
+#else
+ subi r4, r4, 12 /* 12 clocks/loop */
+#endif
+ bge r4, r0, dly_clks
+ ret
+
+
+#if !defined(CONFIG_IDENT_STRING)
+#define CONFIG_IDENT_STRING ""
+#endif
+ .data
+ .globl version_string
+
+version_string:
+ .ascii U_BOOT_VERSION
+ .ascii " (", __DATE__, " - ", __TIME__, ")"
+ .ascii CONFIG_IDENT_STRING, "\0"
diff --git a/cpu/nios2/traps.c b/cpu/nios2/traps.c
new file mode 100644
index 0000000..3f1517d
--- /dev/null
+++ b/cpu/nios2/traps.c
@@ -0,0 +1,42 @@
+/*
+ * (C) Copyright 2004, Psyent Corporation <www.psyent.com>
+ * Scott McNutt <smcnutt@psyent.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/ptrace.h>
+#include <common.h>
+
+void trap_handler (struct pt_regs *regs)
+{
+ /* Just issue warning */
+ printf ("\n\n*** WARNING: unimplemented trap @ %08x\n\n",
+ regs->reg[29] - 4);
+}
+
+void soft_emulation (struct pt_regs *regs)
+{
+ /* TODO: Software emulation of mul/div etc. Until this is
+ * implemented, generate warning and hang.
+ */
+ printf ("\n\n*** ERROR: unimplemented instruction @ %08x\n",
+ regs->reg[29] - 4);
+ hang ();
+}