After commit dc548fbbd2 ("ARM: omap: convert
sched_clock() to use new infrastructure"), OMAPs that use the 32KiHz
"synchronization timer" as their clocksource crash during boot:
[ 0.000000] OMAP clockevent source: GPTIMER1 at 32768 Hz
[ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00000000
[ 0.000000] pgd = c0004000
[ 0.000000] [00000000] *pgd=00000000
[ 0.000000] Internal error: Oops: 80000005 [#1] SMP
[ 0.000000] last sysfs file:
[ 0.000000] Modules linked in:
[ 0.000000] CPU: 0 Tainted: G W (2.6.37-07734-g2467802 #7)
[ 0.000000] PC is at 0x0
[ 0.000000] LR is at sched_clock_poll+0x2c/0x3c
[ 0.000000] pc : [<00000000>] lr : [<c0060b74>] psr: 600001d3
[ 0.000000] sp : c058bfd0 ip : c058a000 fp : 00000000
[ 0.000000] r10: 00000000 r9 : 411fc092 r8 : 800330c8
[ 0.000000] r7 : c05a08e0 r6 : c0034c48 r5 : c05ffc40 r4 : c0034c4c
[ 0.000000] r3 : c05ffe6c r2 : c05a0bc0 r1 : c059f098 r0 : 00000000
[ 0.000000] Flags: nZCv IRQs off FIQs off Mode SVC_32 ISA ARM Segment kernel
[ 0.000000] Control: 10c53c7f Table: 8000404a DAC: 00000017
This is due to the recent ARM init_sched_clock() changes and the late
initialization of the counter_32k clock source. More information here:
http://marc.info/?l=linux-omap&m=129513468605208&w=2
Fix by initializing the counter_32k clocksource during the machine timer
initialization.
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Thomas Weber <weber@corscience.de>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
d8328f3b85