GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/lotus/machine/xmfalcon/compressed/time.c

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <config.h>
+#include <div64.h>
+#include <linux/io.h>
+#include <asm/arch/platform.h>
+
+static struct {
+	unsigned int timebase_l;
+	unsigned int timebase_h;
+} timebase;
+
+/* Returns tick rate in ticks per second */
+unsigned long get_tbclk(void)
+{
+	return CONFIG_SYS_TIMER_RATE;
+}
+
+unsigned long timer_read_counter(void)
+{
+	return ~readl(CONFIG_SYS_TIMER_COUNTER);
+}
+
+unsigned long long get_ticks(void)
+{
+	unsigned long now = timer_read_counter();
+
+	/* increment tbu if tbl has rolled over */
+	if (now < timebase.timebase_l)
+		timebase.timebase_h++;
+	timebase.timebase_l = now;
+	return ((unsigned long long)timebase.timebase_h << 32) | timebase.timebase_l;
+}
+
+unsigned long long usec_to_tick(unsigned long usec)
+{
+	uint64_t tick = usec;
+
+	tick *= get_tbclk();
+	do_div(tick, 1000000);
+	return tick;
+}
+
+void udelay(unsigned long usec)
+{
+	uint64_t tmp;
+
+	tmp = get_ticks() + usec_to_tick(usec);
+
+	while (get_ticks() < tmp+1)
+		;
+}
+
+int timer_init(void)
+{
+	writel(0, TIMER0_REG_BASE + REG_TIMER_CONTROL);
+	writel(~0, TIMER0_REG_BASE + REG_TIMER_RELOAD);
+
+	writel(CFG_TIMER_CTRL, TIMER0_REG_BASE + REG_TIMER_CONTROL);
+
+	return 0;
+}