2 * (C) Copyright 2000-2002
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * (C) Copyright 2002 (440 port)
6 * Scott McNutt, Artesyn Communication Producs, smcnutt@artsyncp.com
8 * (C) Copyright 2003 Motorola Inc. (MPC85xx port)
9 * Xianghua Xiao (X.Xiao@motorola.com)
11 * (C) Copyright 2004 Freescale Semiconductor. (MPC86xx Port)
13 * Srikanth Srinivasan (srikanth.srinivasan@freescale.com)
15 * See file CREDITS for list of people who contributed to this
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License as
20 * published by the Free Software Foundation; either version 2 of
21 * the License, or (at your option) any later version.
23 * This program is distributed in the hope that it will be useful,
24 * but WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
26 * GNU General Public License for more details.
28 * You should have received a copy of the GNU General Public License
29 * along with this program; if not, write to the Free Software
30 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
37 #include <asm/processor.h>
38 #include <ppc_asm.tmpl>
40 unsigned long decrementer_count; /* count value for 1e6/HZ microseconds */
41 unsigned long timestamp;
44 static __inline__ unsigned long get_msr(void)
48 asm volatile ("mfmsr %0":"=r" (msr):);
53 static __inline__ void set_msr(unsigned long msr)
55 asm volatile ("mtmsr %0"::"r" (msr));
58 static __inline__ unsigned long get_dec(void)
62 asm volatile ("mfdec %0":"=r" (val):);
67 static __inline__ void set_dec(unsigned long val)
70 asm volatile ("mtdec %0"::"r" (val));
73 /* interrupt is not supported yet */
74 int interrupt_init_cpu(unsigned *decrementer_count)
79 int interrupt_init(void)
84 * The IRQ0 on Rev 2 is pulled high (low in Rev 1.x) to
85 * implement PEX10 errata. As INT is active high, it
86 * will cause core to take 0x500 interrupt.
88 * Due to the PIC's default pass through mode, as soon
89 * as interrupts are enabled (MSR[EE] = 1), an interrupt
90 * will be taken and u-boot will hang. This is due to a
91 * hardware change (per an errata fix) on new revisions
92 * of the board with Rev 2.x parts.
94 * Setting the PIC to mixed mode prevents the hang.
96 if ((get_svr() & 0xf0) == 0x20) {
97 volatile immap_t *immr = (immap_t *)CFG_IMMR;
98 immr->im_pic.gcr = MPC86xx_PICGCR_RST;
99 while (immr->im_pic.gcr & MPC86xx_PICGCR_RST);
100 immr->im_pic.gcr = MPC86xx_PICGCR_MODE;
103 /* call cpu specific function from $(CPU)/interrupts.c */
104 ret = interrupt_init_cpu(&decrementer_count);
109 decrementer_count = get_tbclk() / CFG_HZ;
110 debug("interrupt init: tbclk() = %d MHz, decrementer_count = %d\n",
111 (get_tbclk() / 1000000),
114 set_dec(decrementer_count);
116 set_msr(get_msr() | MSR_EE);
118 debug("MSR = 0x%08lx, Decrementer reg = 0x%08lx\n",
125 void enable_interrupts(void)
127 set_msr(get_msr() | MSR_EE);
130 /* returns flag if MSR_EE was set before */
131 int disable_interrupts(void)
133 ulong msr = get_msr();
135 set_msr(msr & ~MSR_EE);
136 return (msr & MSR_EE) != 0;
139 void increment_timestamp(void)
145 * timer_interrupt - gets called when the decrementer overflows,
146 * with interrupts disabled.
147 * Trivial implementation - no need to be really accurate.
149 void timer_interrupt_cpu(struct pt_regs *regs)
151 /* nothing to do here */
154 void timer_interrupt(struct pt_regs *regs)
156 /* call cpu specific function from $(CPU)/interrupts.c */
157 timer_interrupt_cpu(regs);
163 /* Restore Decrementer Count */
164 set_dec(decrementer_count);
166 #if defined(CONFIG_WATCHDOG) || defined (CONFIG_HW_WATCHDOG)
167 if ((timestamp % (CFG_WATCHDOG_FREQ)) == 0)
169 #endif /* CONFIG_WATCHDOG || CONFIG_HW_WATCHDOG */
171 #ifdef CONFIG_STATUS_LED
172 status_led_tick(timestamp);
173 #endif /* CONFIG_STATUS_LED */
175 #ifdef CONFIG_SHOW_ACTIVITY
176 board_show_activity(timestamp);
177 #endif /* CONFIG_SHOW_ACTIVITY */
181 void reset_timer(void)
186 ulong get_timer(ulong base)
188 return timestamp - base;
191 void set_timer(ulong t)
197 * Install and free a interrupt handler. Not implemented yet.
200 void irq_install_handler(int vec, interrupt_handler_t *handler, void *arg)
204 void irq_free_handler(int vec)
209 * irqinfo - print information about PCI devices,not implemented.
211 int do_irqinfo(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
213 printf("\nInterrupt-unsupported:\n");
219 * Handle external interrupts
221 void external_interrupt(struct pt_regs *regs)
223 puts("external_interrupt (oops!)\n");