123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172 |
- /*
- * Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
- * Copyright (C) 2007-2009 PetaLogix
- * Copyright (C) 2006 Atmark Techno, Inc.
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- */
- #include <linux/sched.h>
- #include <linux/io.h>
- #include <asm/setup.h>
- #include <asm/page.h>
- #include <asm/prom.h>
- static unsigned int base_addr;
- void microblaze_heartbeat(void)
- {
- static unsigned int cnt, period, dist;
- if (base_addr) {
- if (cnt == 0 || cnt == dist)
- out_be32(base_addr, 1);
- else if (cnt == 7 || cnt == dist + 7)
- out_be32(base_addr, 0);
- if (++cnt > period) {
- cnt = 0;
- /*
- * The hyperbolic function below modifies the heartbeat
- * period length in dependency of the current (5min)
- * load. It goes through the points f(0)=126, f(1)=86,
- * f(5)=51, f(inf)->30.
- */
- period = ((672 << FSHIFT) / (5 * avenrun[0] +
- (7 << FSHIFT))) + 30;
- dist = period / 4;
- }
- }
- }
- void microblaze_setup_heartbeat(void)
- {
- struct device_node *gpio = NULL;
- int *prop;
- int j;
- const char * const gpio_list[] = {
- "xlnx,xps-gpio-1.00.a",
- NULL
- };
- for (j = 0; gpio_list[j] != NULL; j++) {
- gpio = of_find_compatible_node(NULL, NULL, gpio_list[j]);
- if (gpio)
- break;
- }
- if (gpio) {
- base_addr = be32_to_cpup(of_get_property(gpio, "reg", NULL));
- base_addr = (unsigned long) ioremap(base_addr, PAGE_SIZE);
- pr_notice("Heartbeat GPIO at 0x%x\n", base_addr);
- /* GPIO is configured as output */
- prop = (int *) of_get_property(gpio, "xlnx,is-bidir", NULL);
- if (prop)
- out_be32(base_addr + 4, 0);
- }
- }
|