Hi, On Tue, 7 Dec 2010, Chikkature Rajashekar, Madhusudhan wrote: > On Tue, Dec 7, 2010 at 1:51 PM, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote: > > > > It is at least because omap_pm_get_dev_context_loss_count() is not > > implemented. Tero Kristo was looking at that recently. > > > > Yes. I agree that is the problem. In the .32 kernel I had hooked it to > "get_last_off_on_transaction_id" which helped. > But that functionality does not exist anymore. So something equivalent > to tell the driver when the OFF was hit will make it work. OK, let's see if we can get that fixed in at least some trivial way for 2.6.38. While working on this, I applied this trivial patch: diff --git a/arch/arm/plat-omap/omap-pm-noop.c b/arch/arm/plat-omap/omap-pm-noop.c index e129ce8..781aa5f 100644 --- a/arch/arm/plat-omap/omap-pm-noop.c +++ b/arch/arm/plat-omap/omap-pm-noop.c @@ -30,6 +30,8 @@ struct omap_opp *dsp_opps; struct omap_opp *mpu_opps; struct omap_opp *l3_opps; +static int dummy_context_loss_counter; + /* * Device-driver-originated constraints (via board-*.c files) */ @@ -303,7 +305,7 @@ int omap_pm_get_dev_context_loss_count(struct device *dev) * off counter. */ - return 0; + return dummy_context_loss_counter++; } ... which causes drivers to believe that device context has been lost after each call to omap_pm_get_dev_context_loss_count(). Brutal, but effective for chasing out context save/restore bugs. This patch causes an abort in the MMC driver with the current linux-omap master: [ 1.960693] Unhandled fault: external abort on non-linefetch (0x1028) at 0xfa09c014 [ 1.968872] Internal error: : 1028 [#1] SMP [ 1.973266] last sysfs file: [ 1.976379] Modules linked in: [ 1.979583] CPU: 0 Not tainted (2.6.37-rc4-09012-gfea0fb8 #65) [ 1.986083] PC is at omap_hsmmc_context_restore+0x58/0x2ec [ 1.991851] LR is at omap_hsmmc_context_restore+0x4c/0x2ec [ 1.997619] pc : [<c0345590>] lr : [<c0345584>] psr: 20000013 [ 1.997619] sp : cf82deb0 ip : cf82c000 fp : cf890408 [ 2.009643] r10: cf826160 r9 : 00000053 r8 : 00000001 [ 2.015136] r7 : cfad2000 r6 : cfad23c0 r5 : 00000000 r4 : ffff6b1f [ 2.021972] r3 : 0000000e r2 : fa09c000 r1 : fa09c014 r0 : ffff6b22 [ 2.028808] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 2.036499] Control: 10c5387d Table: 80004019 DAC: 00000017 [ 2.042510] Process swapper (pid: 1, stack limit = 0xcf82c2f8) [ 2.048645] Stack: (0xcf82deb0 to 0xcf82e000) [ 2.053192] dea0: cfad23c0 00000000 cfad2000 cfad23c0 [ 2.061798] dec0: 00000000 c0345844 cfad2000 00000000 cfad2000 c0338040 00000000 00000001 [ 2.070373] dee0: cfad2000 c002c728 00000000 00000003 cf886c08 cfad0a60 c05fdbc0 cf890408 [ 2.078948] df00: cf890408 c05fdbc0 cfaef1a0 c05f06b8 00000000 00000000 00000000 c02a0368 [ 2.087524] df20: cf890408 c029f388 cf890408 cf89043c c05fdbc0 c029f4b0 00000000 c029f448 [ 2.096130] df40: c05fdbc0 c029eb3c cf826eb8 cf8b5890 cf8001e0 00000080 c05fdbc0 c029e468 [ 2.104705] df60: c04f3804 00000468 00000000 c05fdbac c061bd54 c05fdbc0 c061bd4c c002c400 [ 2.113281] df80: 00000000 c029f7a8 c05fdbac c061bd54 c05aa190 c061bd4c c002c400 c02a0770 [ 2.121856] dfa0: c00335dc c061bd54 c05aa190 c0050574 00000000 00000000 c0503d6c 00000192 [ 2.130462] dfc0: c061bd54 c00335dc c061bd54 c05aa190 c061bd4c 00000000 00000000 c00084ec [ 2.139038] dfe0: 00000000 c00083a0 c005bcf0 00000013 00000000 c005bcf0 1177ed0a 0073ef00 [ 2.147644] [<c0345590>] (omap_hsmmc_context_restore+0x58/0x2ec) from [<c0345844>] (omap_hsmmc_enable_fclk+0x20/0x28) [ 2.158782] [<c0345844>] (omap_hsmmc_enable_fclk+0x20/0x28) from [<c0338040>] (mmc_host_enable+0x6c/0x90) [ 2.168823] [<c0338040>] (mmc_host_enable+0x6c/0x90) from [<c002c728>] (omap_hsmmc_probe+0x314/0x96c) [ 2.178497] [<c002c728>] (omap_hsmmc_probe+0x314/0x96c) from [<c02a0368>] (platform_drv_probe+0x18/0x1c) [ 2.188476] [<c02a0368>] (platform_drv_probe+0x18/0x1c) from [<c029f388>] (driver_probe_device+0xc8/0x188) [ 2.198608] [<c029f388>] (driver_probe_device+0xc8/0x188) from [<c029f4b0>] (__driver_attach+0x68/0x8c) [ 2.208465] [<c029f4b0>] (__driver_attach+0x68/0x8c) from [<c029eb3c>] (bus_for_each_dev+0x44/0x74) [ 2.217956] [<c029eb3c>] (bus_for_each_dev+0x44/0x74) from [<c029e468>] (bus_add_driver+0x104/0x294) [ 2.227569] [<c029e468>] (bus_add_driver+0x104/0x294) from [<c029f7a8>] (driver_register+0xa8/0x130) [ 2.237152] [<c029f7a8>] (driver_register+0xa8/0x130) from [<c02a0770>] (platform_driver_probe+0x18/0x8c) [ 2.247192] [<c02a0770>] (platform_driver_probe+0x18/0x8c) from [<c0050574>] (do_one_initcall+0xc8/0x1a0) [ 2.257263] [<c0050574>] (do_one_initcall+0xc8/0x1a0) from [<c00084ec>] (kernel_init+0x14c/0x214) [ 2.266571] [<c00084ec>] (kernel_init+0x14c/0x214) from [<c005bcf0>] (kernel_thread_exit+0x0/0x8) [ 2.275878] Code: ebf53fa3 e5962048 e2821014 e0800004 (e5913000) [ 2.282409] ---[ end trace a0fb0e5d1754cad1 ]--- [ 2.287353] Kernel panic - not syncing: Attempted to kill init! Looks like 0xfa09c014 is the MMC SYSSTATUS register... maybe there's something wrong with the clock control. - Paul
