19 Mar
2015
19 Mar
'15
7:24 p.m.
On 03/19/2015 11:17 AM, Mark Rutland wrote:
On Thu, Mar 19, 2015 at 06:16:25PM +0000, York Sun wrote:
On 03/19/2015 11:08 AM, Mark Rutland wrote:
+int timer_init(void) +{
- u32 __iomem *cntcr = (u32 *)CONFIG_SYS_FSL_TIMER_ADDR;
- u32 __iomem *cltbenr = (u32 *)CONFIG_SYS_FSL_PMU_CLTBENR;
+#ifdef COUNTER_FREQUENCY_REAL
- unsigned long cntfrq = COUNTER_FREQUENCY_REAL;
- /* Update with accurate clock frequency */
- asm volatile("msr cntfrq_el0, %0" : : "r" (cntfrq) : "memory");
+#endif
Is this executed on all CPUs, or do secondary CPUs have CNTFRQ programmed with the correct value elsewhere?
Only the primary CPU runs here. The secondary CPU doesn't come here.
Ok. Where does CNTFRQ get programmed for those CPUs?
If it's necessary to write COUNTER_FREQUENCY_REAL to the primary CPU's CNTFRQ, that's also necessary on the secondaries before they enter the OS.
Hmm, this may be a bug. Didn't hear any complain from Linux users. We found the timer wasn't correct during bring-up. Let me check with internal team.
Thanks, Mark.
York