PM: omap_wdt: modprobe fails

PM: omap_wdt: modprobe fails

[Roger Quadros]

hi,

   modprobe omap_wdt fails in omap PM branch. below is the trace log.
any idea why?

   i wonder weather fails in master too.

regards,
-roger

[   37.218078] Unhandled fault: external abort on non-linefetch (0x1028) at 
0xd8314034
[   37.225982] Internal error: : 1028 [#1]
[   37.229888] Modules linked in: omap_wdt(+) tsc2005 rtc_twl4030 rtc_core
[   37.236633] CPU: 0    Not tainted  (2.6.29-omap1-06218-gcc1a62b #93)
[   37.243072] PC is at omap_wdt_disable+0x20/0x4c [omap_wdt]
[   37.248626] LR is at omap_wdt_probe+0xf8/0x1ec [omap_wdt]
[   37.254089] pc : [<bf0180bc>]    lr : [<bf01c130>]    psr: a0000013
[   37.254119] sp : ce927db0  ip : ce927dc0  fp : ce927dbc
[   37.265716] r10: c032ddf0  r9 : bf01928c  r8 : c032ddd0
[   37.270996] r7 : ce9712a0  r6 : c032ddf8  r5 : 00000000  r4 : cf160be0
[   37.277587] r3 : 0000aaaa  r2 : 00000000  r1 : d8314048  r0 : d8314000
[   37.284179] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   37.291412] Control: 10c5387d  Table: 8e94c019  DAC: 00000015
[   37.297210] Process modprobe (pid: 743, stack limit = 0xce9262e0)
[   37.303375] Stack: (0xce927db0 to 0xce928000)
[   37.307769] 7da0:                                     ce927df4 ce927dc0 
bf01c130 bf0180a
[   37.316253] 7dc0: 00000000 c034a3d8 ce927de4 c032ddf8 c032dea4 bf019154 
bf019154 c034a3d
[   37.324707] 7de0: ce926000 40024000 ce927e04 ce927df8 c017bf98 bf01c044 
ce927e24 ce927e0
[   37.333190] 7e00: c017b180 c017bf84 c032ddf8 c032dea4 bf019154 bf019154 
ce927e44 ce927e2
[   37.341644] 7e20: c017b294 c017b0b8 00000000 ce927e48 c017b22c bf019154 
ce927e6c ce927e4
[   37.350128] 7e40: c017a590 c017b238 cf81ce5c c032de4c 00000000 bf019154 
c0354580 ce870aa
[   37.358581] 7e60: ce927e7c ce927e70 c017afc4 c017a550 ce927eac ce927e80 
c017ab58 c017afb
[   37.367065] 7e80: bf018650 00000000 c0029a64 00002518 bf019154 c0354580 
00000000 c0029a6
[   37.375518] 7ea0: ce927ed4 ce927eb0 c017b4b8 c017aabc 00002518 bf019184 
c0354580 0000000
[   37.384002] 7ec0: c0029a64 40024000 ce927ee4 ce927ed8 c017c3b4 c017b42c 
ce927ef4 ce927ee
[   37.392456] 7ee0: bf01c028 c017c354 ce927f7c ce927ef8 c00292c0 bf01c00c 
c014280c c0258b5
[   37.400939] 7f00: bf01c000 00000000 bf019184 ffffffff ce927f34 ce927f20 
c0065548 c014276
[   37.409393] 7f20: 00000000 c03319dc ce927f64 ce927f38 c0065f44 c006552c 
00000000 ce927f4
[   37.417877] 7f40: c0256bf0 00002518 bf019184 4001e000 00000000 00002518 
bf019184 4001e00
[   37.426330] 7f60: 00000000 c0029a64 ce926000 40024000 ce927fa4 ce927f80 
c007ac60 c002926
[   37.434814] 7f80: 00000003 00000000 bea3a98c 4001cbe0 00000000 00000080 
00000000 ce927fa
[   37.443267] 7fa0: c00298e0 c007abd0 bea3a98c 4001cbe0 4001e000 00002518 
0001afa0 0000251
[   37.451751] 7fc0: bea3a98c 4001cbe0 00000000 00000080 00000000 00000000 
40024000 bea3a9c
[   37.460205] 7fe0: 00000000 bea3a94c 0000b6e8 400f0f64 60000010 4001e000 
0177aeee 0000000
[   37.468688] Backtrace:
[   37.471191] [<bf01809c>] (omap_wdt_disable+0x0/0x4c [omap_wdt]) from 
[<bf01c130>] (omap_)
[   37.482238] [<bf01c038>] (omap_wdt_probe+0x0/0x1ec [omap_wdt]) from 
[<c017bf98>] (platfo)
[   37.492492] [<c017bf78>] (platform_drv_probe+0x0/0x24) from [<c017b180>] 
(driver_probe_d)
[   37.502227] [<c017b0ac>] (driver_probe_device+0x0/0x180) from [<c017b294>] 
(__driver_att)
[   37.511657]  r7:bf019154 r6:bf019154 r5:c032dea4 r4:c032ddf8
[   37.517456] [<c017b22c>] (__driver_attach+0x0/0x8c) from [<c017a590>] 
(bus_for_each_dev+)
[   37.526550]  r7:bf019154 r6:c017b22c r5:ce927e48 r4:00000000
[   37.532318] [<c017a544>] (bus_for_each_dev+0x0/0x84) from [<c017afc4>] 
(driver_attach+0x)
[   37.541259]  r7:ce870aa0 r6:c0354580 r5:bf019154 r4:00000000
[   37.547027] [<c017afa4>] (driver_attach+0x0/0x28) from [<c017ab58>] 
(bus_add_driver+0xa8)
[   37.555877] [<c017aab0>] (bus_add_driver+0x0/0x214) from [<c017b4b8>] 
(driver_register+0)
[   37.564971]  r8:c0029a64 r7:00000000 r6:c0354580 r5:bf019154 r4:00002518
[   37.571807] [<c017b420>] (driver_register+0x0/0x120) from [<c017c3b4>] 
(platform_driver_)
[   37.581695] [<c017c348>] (platform_driver_register+0x0/0x88) from 
[<bf01c028>] (omap_wdt)
[   37.592315] [<bf01c000>] (omap_wdt_init+0x0/0x38 [omap_wdt]) from 
[<c00292c0>] (__except)
[   37.602661] [<c0029260>] (__exception_text_end+0x0/0x19c) from [<c007ac60>] 
(sys_init_mo)
[   37.612304] [<c007abc4>] (sys_init_module+0x0/0x1a4) from [<c00298e0>] 
(ret_fast_syscall)
[   37.621429]  r7:00000080 r6:00000000 r5:4001cbe0 r4:bea3a98c
[   37.627197] Code: e30a3aaa e2801048 e5803048 eaffffff (e5903034)
[   37.633514] ---[ end trace 1e4c3ca59877c8bf ]---
udevd-event[741]: run_program: '/sbin/modprobe' abnormal exit

RE: omap_wdt: modprobe fails

[Woodruff, Richard]

> From: linux-omap-owner@vger.kernel.org [mailto:linux-omap-
> owner@vger.kernel.org] On Behalf Of Roger Quadros
> Sent: Tuesday, April 07, 2009 6:11 AM

>    modprobe omap_wdt fails in omap PM branch. below is the trace log.
> any idea why?
>
>    i wonder weather fails in master too.

Looks like it. I had noticed it broken in one older tree a while back.

The probe routine at omap_wdt_disable() touches registers without trying to enable the clocks to the module.  Before this a clk_get happens but no clk_enable.

314         platform_set_drvdata(pdev, wdev);
315
316         omap_wdt_disable(wdev);

Actually there were a number of bugs here.  The only reason the probe works at all is because the boot loader turned the clock on to stop it.  If you make sure its shut off in loader you will crash here normally.

Some fixes were made in an older tree which you can draw from to fix it.

http://git.omapzoom.org/?p=repo/omapkernel.git;a=commitdiff;h=c1753c36b04db34660b6df94e5f395401985f0da

Regards,
Richard W.