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authorfishsoupisgood <github@madingley.org>2019-04-29 01:17:54 +0100
committerfishsoupisgood <github@madingley.org>2019-05-27 03:43:43 +0100
commit3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch)
tree65ca85f13617aee1dce474596800950f266a456c /roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c
downloadqemu-master.tar.gz
qemu-master.tar.bz2
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Initial import of qemu-2.4.1HEADmaster
Diffstat (limited to 'roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c')
-rw-r--r--roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c b/roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c
new file mode 100644
index 00000000..ba1e616b
--- /dev/null
+++ b/roms/u-boot/arch/arm/cpu/arm920t/s3c24x0/timer.c
@@ -0,0 +1,160 @@
+/*
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#ifdef CONFIG_S3C24X0
+
+#include <asm/io.h>
+#include <asm/arch/s3c24x0_cpu.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int timer_init(void)
+{
+ struct s3c24x0_timers *timers = s3c24x0_get_base_timers();
+ ulong tmr;
+
+ /* use PWM Timer 4 because it has no output */
+ /* prescaler for Timer 4 is 16 */
+ writel(0x0f00, &timers->tcfg0);
+ if (gd->arch.tbu == 0) {
+ /*
+ * for 10 ms clock period @ PCLK with 4 bit divider = 1/2
+ * (default) and prescaler = 16. Should be 10390
+ * @33.25MHz and 15625 @ 50 MHz
+ */
+ gd->arch.tbu = get_PCLK() / (2 * 16 * 100);
+ gd->arch.timer_rate_hz = get_PCLK() / (2 * 16);
+ }
+ /* load value for 10 ms timeout */
+ writel(gd->arch.tbu, &timers->tcntb4);
+ /* auto load, manual update of timer 4 */
+ tmr = (readl(&timers->tcon) & ~0x0700000) | 0x0600000;
+ writel(tmr, &timers->tcon);
+ /* auto load, start timer 4 */
+ tmr = (tmr & ~0x0700000) | 0x0500000;
+ writel(tmr, &timers->tcon);
+ gd->arch.lastinc = 0;
+ gd->arch.tbl = 0;
+
+ return 0;
+}
+
+/*
+ * timer without interrupts
+ */
+ulong get_timer(ulong base)
+{
+ return get_timer_masked() - base;
+}
+
+void __udelay (unsigned long usec)
+{
+ ulong tmo;
+ ulong start = get_ticks();
+
+ tmo = usec / 1000;
+ tmo *= (gd->arch.tbu * 100);
+ tmo /= 1000;
+
+ while ((ulong) (get_ticks() - start) < tmo)
+ /*NOP*/;
+}
+
+ulong get_timer_masked(void)
+{
+ ulong tmr = get_ticks();
+
+ return tmr / (gd->arch.timer_rate_hz / CONFIG_SYS_HZ);
+}
+
+void udelay_masked(unsigned long usec)
+{
+ ulong tmo;
+ ulong endtime;
+ signed long diff;
+
+ if (usec >= 1000) {
+ tmo = usec / 1000;
+ tmo *= (gd->arch.tbu * 100);
+ tmo /= 1000;
+ } else {
+ tmo = usec * (gd->arch.tbu * 100);
+ tmo /= (1000 * 1000);
+ }
+
+ endtime = get_ticks() + tmo;
+
+ do {
+ ulong now = get_ticks();
+ diff = endtime - now;
+ } while (diff >= 0);
+}
+
+/*
+ * This function is derived from PowerPC code (read timebase as long long).
+ * On ARM it just returns the timer value.
+ */
+unsigned long long get_ticks(void)
+{
+ struct s3c24x0_timers *timers = s3c24x0_get_base_timers();
+ ulong now = readl(&timers->tcnto4) & 0xffff;
+
+ if (gd->arch.lastinc >= now) {
+ /* normal mode */
+ gd->arch.tbl += gd->arch.lastinc - now;
+ } else {
+ /* we have an overflow ... */
+ gd->arch.tbl += gd->arch.lastinc + gd->arch.tbu - now;
+ }
+ gd->arch.lastinc = now;
+
+ return gd->arch.tbl;
+}
+
+/*
+ * This function is derived from PowerPC code (timebase clock frequency).
+ * On ARM it returns the number of timer ticks per second.
+ */
+ulong get_tbclk(void)
+{
+ return CONFIG_SYS_HZ;
+}
+
+/*
+ * reset the cpu by setting up the watchdog timer and let him time out
+ */
+void reset_cpu(ulong ignored)
+{
+ struct s3c24x0_watchdog *watchdog;
+
+ watchdog = s3c24x0_get_base_watchdog();
+
+ /* Disable watchdog */
+ writel(0x0000, &watchdog->wtcon);
+
+ /* Initialize watchdog timer count register */
+ writel(0x0001, &watchdog->wtcnt);
+
+ /* Enable watchdog timer; assert reset at timer timeout */
+ writel(0x0021, &watchdog->wtcon);
+
+ while (1)
+ /* loop forever and wait for reset to happen */;
+
+ /*NOTREACHED*/
+}
+
+#endif /* CONFIG_S3C24X0 */