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-rw-r--r--cpu/arm920t/interrupts.c304
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diff --git a/cpu/arm920t/interrupts.c b/cpu/arm920t/interrupts.c
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+/*
+ * (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 <arm920t.h>
+#if defined(CONFIG_S3C2400)
+#include <s3c2400.h>
+#elif defined(CONFIG_S3C2410)
+#include <s3c2410.h>
+#endif
+
+#include <asm/proc-armv/ptrace.h>
+
+extern void reset_cpu(ulong addr);
+int timer_load_val = 0;
+
+/* macro to read the 16 bit timer */
+#define READ_TIMER (rTCNTO4 & 0xffff)
+
+#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;
+
+int interrupt_init (void)
+{
+ /* use PWM Timer 4 because it has no output */
+ /* prescaler for Timer 4 is 16 */
+ rTCFG0 = 0x0f00;
+ if (timer_load_val == 0)
+ {
+ /*
+ * for 10 ms clock period @ PCLK with 4 bit divider = 1/2
+ * (default) and prescaler = 16. Should be 10390
+ * @33.25MHz and 15625 @ 50 MHz
+ */
+ timer_load_val = get_PCLK()/(2 * 16 * 100);
+ }
+ /* load value for 10 ms timeout */
+ lastdec = rTCNTB4 = timer_load_val;
+ /* auto load, manual update of Timer 4 */
+ rTCON = 0x600000;
+ /* auto load, start Timer 4 */
+ rTCON = 0x500000;
+ timestamp = 0;
+
+ 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;
+}
+
+void udelay (unsigned long usec)
+{
+ ulong tmo;
+
+ tmo = usec / 1000;
+ tmo *= (timer_load_val * 100);
+ tmo /= 1000;
+
+ tmo += get_timer (0);
+
+ while (get_timer_masked () < tmo)
+ /*NOP*/;
+}
+
+void reset_timer_masked (void)
+{
+ /* reset time */
+ lastdec = READ_TIMER;
+ timestamp = 0;
+}
+
+ulong get_timer_masked (void)
+{
+ ulong now = READ_TIMER;
+
+ if (lastdec >= now) {
+ /* normal mode */
+ timestamp += lastdec - now;
+ } else {
+ /* we have an overflow ... */
+ timestamp += lastdec + timer_load_val - now;
+ }
+ lastdec = now;
+
+ return timestamp;
+}
+
+void udelay_masked (unsigned long usec)
+{
+ ulong tmo;
+
+ tmo = usec / 1000;
+ tmo *= (timer_load_val * 100);
+ tmo /= 1000;
+
+ reset_timer_masked ();
+
+ while (get_timer_masked () < tmo)
+ /*NOP*/;
+}
+
+/*
+ * 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)
+{
+ ulong tbclk;
+
+#if defined(CONFIG_SMDK2400) || defined(CONFIG_TRAB)
+ tbclk = timer_load_val * 100;
+#elif defined(CONFIG_SMDK2410)
+ tbclk = CFG_HZ;
+#endif
+
+ return tbclk;
+}