3 * Daniel Engström, Omicron Ceti AB <daniel@omicron.se>.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24 /* stuff specific for the sc520, but independent of implementation */
27 #include <asm/interrupt.h>
28 #include <asm/ic/sc520.h>
30 void sc520_timer_isr(void)
32 /* Ack the GP Timer Interrupt */
33 write_mmcr_byte (SC520_GPTMRSTA, 0x02);
38 /* Map GP Timer 1 to Master PIC IR0 */
39 write_mmcr_byte (SC520_GPTMR1MAP, 0x01);
41 /* Disable GP Timers 1 & 2 - Allow configuration writes */
42 write_mmcr_word (SC520_GPTMR1CTL, 0x4000);
43 write_mmcr_word (SC520_GPTMR2CTL, 0x4000);
45 /* Reset GP Timers 1 & 2 */
46 write_mmcr_word (SC520_GPTMR1CNT, 0x0000);
47 write_mmcr_word (SC520_GPTMR2CNT, 0x0000);
49 /* Setup GP Timer 2 as a 100kHz (10us) prescaler */
50 write_mmcr_word (SC520_GPTMR2MAXCMPA, 83);
51 write_mmcr_word (SC520_GPTMR2CTL, 0xc001);
53 /* Setup GP Timer 1 as a 1000 Hz (1ms) interrupt generator */
54 write_mmcr_word (SC520_GPTMR1MAXCMPA, 100);
55 write_mmcr_word (SC520_GPTMR1CTL, 0xe009);
57 /* Register the SC520 specific timer interrupt handler */
58 register_timer_isr (sc520_timer_isr);
60 /* Install interrupt handler for GP Timer 1 */
61 irq_install_handler (0, timer_isr, NULL);
64 /* Clear the GP Timer 1 status register to get the show rolling*/
65 write_mmcr_byte (SC520_GPTMRSTA, 0x02);
70 void udelay(unsigned long usec)
75 read_mmcr_word (SC520_SWTMRMILLI);
76 read_mmcr_word (SC520_SWTMRMICRO);
79 m += read_mmcr_word (SC520_SWTMRMILLI);
80 u = read_mmcr_word (SC520_SWTMRMICRO) + (m * 1000);