2 * (C) Copyright 2008-2011
3 * Graeme Russ, <graeme.russ@gmail.com>
6 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
8 * See file CREDITS for list of people who contributed to this
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation; either version 2 of
14 * the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29 #include <asm/interrupt.h>
30 #include <asm/ic/sc520.h>
32 void sc520_timer_isr(void)
34 /* Ack the GP Timer Interrupt */
35 writeb(0x02, &sc520_mmcr->gptmrsta);
40 /* Register the SC520 specific timer interrupt handler */
41 register_timer_isr (sc520_timer_isr);
43 /* Install interrupt handler for GP Timer 1 */
44 irq_install_handler (0, timer_isr, NULL);
46 /* Map GP Timer 1 to Master PIC IR0 */
47 writeb(0x01, &sc520_mmcr->gp_tmr_int_map[1]);
49 /* Disable GP Timers 1 & 2 - Allow configuration writes */
50 writew(0x4000, &sc520_mmcr->gptmr1ctl);
51 writew(0x4000, &sc520_mmcr->gptmr2ctl);
53 /* Reset GP Timers 1 & 2 */
54 writew(0x0000, &sc520_mmcr->gptmr1cnt);
55 writew(0x0000, &sc520_mmcr->gptmr2cnt);
57 /* Setup GP Timer 2 as a 100kHz (10us) prescaler */
58 writew(83, &sc520_mmcr->gptmr2maxcmpa);
59 writew(0xc001, &sc520_mmcr->gptmr2ctl);
61 /* Setup GP Timer 1 as a 1000 Hz (1ms) interrupt generator */
62 writew(100, &sc520_mmcr->gptmr1maxcmpa);
63 writew(0xe009, &sc520_mmcr->gptmr1ctl);
67 /* Clear the GP Timer 1 status register to get the show rolling*/
68 writeb(0x02, &sc520_mmcr->gptmrsta);
73 /* Allow boards to override udelay implementation */
74 void __udelay(unsigned long usec)
75 __attribute__((weak, alias("sc520_udelay")));
77 void sc520_udelay(unsigned long usec)
83 temp = readw(&sc520_mmcr->swtmrmilli);
84 temp = readw(&sc520_mmcr->swtmrmicro);
87 m += readw(&sc520_mmcr->swtmrmilli);
88 u = readw(&sc520_mmcr->swtmrmicro) + (m * 1000);