[SPARC64]: Fetch bootup time of day from Hypervisor. (4bdff414) · Commits · github.com / kvm-riscv / linux

arch/sparc64/kernel/time.c

+50 −8

Original line number	Diff line number	Diff line
		@@ -683,6 +683,48 @@ static void __init set_system_time(void)
		}
		}

		/* davem suggests we keep this within the 4M locked kernel image */
		static u32 starfire_get_time(void)
		{
		static char obp_gettod[32];
		static u32 unix_tod;

		sprintf(obp_gettod, "h# %08x unix-gettod",
		(unsigned int) (long) &unix_tod);
		prom_feval(obp_gettod);

		return unix_tod;
		}

		static u32 hypervisor_get_time(void)
		{
		register unsigned long func asm("%o5");
		register unsigned long arg0 asm("%o0");
		register unsigned long arg1 asm("%o1");
		int retries = 10000;

		retry:
		func = HV_FAST_TOD_GET;
		arg0 = 0;
		arg1 = 0;
		__asm__ __volatile__("ta %6"
		: "=&r" (func), "=&r" (arg0), "=&r" (arg1)
		: "0" (func), "1" (arg0), "2" (arg1),
		"i" (HV_FAST_TRAP));
		if (arg0 == HV_EOK)
		return arg1;
		if (arg0 == HV_EWOULDBLOCK) {
		if (--retries > 0) {
		udelay(100);
		goto retry;
		}
		printk(KERN_WARNING "SUN4V: tod_get() timed out.\n");
		return 0;
		}
		printk(KERN_WARNING "SUN4V: tod_get() not supported.\n");
		return 0;
		}

		void __init clock_probe(void)
		{
		struct linux_prom_registers clk_reg[2];
		@@ -702,14 +744,14 @@ void __init clock_probe(void)


		if (this_is_starfire) {
		/* davem suggests we keep this within the 4M locked kernel image */
		static char obp_gettod[256];
		static u32 unix_tod;

		sprintf(obp_gettod, "h# %08x unix-gettod",
		(unsigned int) (long) &unix_tod);
		prom_feval(obp_gettod);
		xtime.tv_sec = unix_tod;
		xtime.tv_sec = starfire_get_time();
		xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
		set_normalized_timespec(&wall_to_monotonic,
		-xtime.tv_sec, -xtime.tv_nsec);
		return;
		}
		if (tlb_type == hypervisor) {
		xtime.tv_sec = hypervisor_get_time();
		xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
		set_normalized_timespec(&wall_to_monotonic,
		-xtime.tv_sec, -xtime.tv_nsec);