diff options
Diffstat (limited to 'arch/i386/cpu/sc520/sc520_timer.c')
-rw-r--r-- | arch/i386/cpu/sc520/sc520_timer.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/i386/cpu/sc520/sc520_timer.c b/arch/i386/cpu/sc520/sc520_timer.c new file mode 100644 index 0000000..93b5b55 --- /dev/null +++ b/arch/i386/cpu/sc520/sc520_timer.c @@ -0,0 +1,84 @@ +/* + * (C) Copyright 2002 + * Daniel Engström, Omicron Ceti AB <daniel@omicron.se>. + * + * 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 + */ + +/* stuff specific for the sc520, but independent of implementation */ + +#include <common.h> +#include <asm/interrupt.h> +#include <asm/ic/sc520.h> + +void sc520_timer_isr(void) +{ + /* Ack the GP Timer Interrupt */ + sc520_mmcr->gptmrsta = 0x02; +} + +int timer_init(void) +{ + /* Register the SC520 specific timer interrupt handler */ + register_timer_isr (sc520_timer_isr); + + /* Install interrupt handler for GP Timer 1 */ + irq_install_handler (0, timer_isr, NULL); + + /* Map GP Timer 1 to Master PIC IR0 */ + sc520_mmcr->gp_tmr_int_map[1] = 0x01; + + /* Disable GP Timers 1 & 2 - Allow configuration writes */ + sc520_mmcr->gptmr1ctl = 0x4000; + sc520_mmcr->gptmr2ctl = 0x4000; + + /* Reset GP Timers 1 & 2 */ + sc520_mmcr->gptmr1cnt = 0x0000; + sc520_mmcr->gptmr2cnt = 0x0000; + + /* Setup GP Timer 2 as a 100kHz (10us) prescaler */ + sc520_mmcr->gptmr2maxcmpa = 83; + sc520_mmcr->gptmr2ctl = 0xc001; + + /* Setup GP Timer 1 as a 1000 Hz (1ms) interrupt generator */ + sc520_mmcr->gptmr1maxcmpa = 100; + sc520_mmcr->gptmr1ctl = 0xe009; + + unmask_irq (0); + + /* Clear the GP Timer 1 status register to get the show rolling*/ + sc520_mmcr->gptmrsta = 0x02; + + return 0; +} + +void __udelay(unsigned long usec) +{ + int m = 0; + long u; + long temp; + + temp = sc520_mmcr->swtmrmilli; + temp = sc520_mmcr->swtmrmicro; + + do { + m += sc520_mmcr->swtmrmilli; + u = sc520_mmcr->swtmrmicro + (m * 1000); + } while (u < usec); +} |