On Wed, Jun 29, 2011 at 8:12 PM, Paul Walmsley <paul@xxxxxxxxx> wrote: > On Wed, 29 Jun 2011, T Krishnamoorthy, Balaji wrote: > >> On Wed, Jun 29, 2011 at 12:11 AM, Paul Walmsley <paul@xxxxxxxxx> wrote: >> > On Tue, 28 Jun 2011, T Krishnamoorthy, Balaji wrote: >> > >> >> On Tue, Jun 28, 2011 at 10:52 PM, Paul Walmsley <paul@xxxxxxxxx> wrote: >> >> > >> >> > On Wed, 22 Jun 2011, Balaji T K wrote: >> >> > >> >> >> Use runtime autosuspend APIs to enable auto suspend delay >> >> > >> >> > Does this really need to use runtime autosuspend? Seems to me that since >> >> > PM runtime is just controlling the MMC IP blocks and not the regulators in >> >> > this instance, this could simply use pm_runtime_put*() and just avoid the >> >> > extra power wastage and complexity involved in autosuspend. >> >> >> >> I have seen some instabilities if delay is very less, on some production boards. >> > >> > Could you be more specific? What type of instabilities did you see? >> >> There have been some experiments on our customer programs to reduce this >> value to a few ms and infrequent crashes were observed (stress testing >> for several hours) while trying to access the controller registers. > > Was there an oops? Any analysis, etc.? OOPS pointed to omap_hsmmc_prepare_data / set_data_timeout Use case was MMC + SDIO +GPS activity, on kernel 2.6.35 though. Unhandled fault: imprecise external abort (0x1406) at 0x4073102c Internal error: : 1406 [#1] PREEMPT SMP last sysfs file: /sys/devices/platform/switch-sio/usb_sel Modules linked in: param(P) j4fs(P) vibetonz Si4709_driver fm_drv(C) bt_drv(C) st_drv(C) CPU: 0 Tainted: P WC (2.6.35.7 #2) PC is at clk_get_rate+0x4/0x48 LR is at set_data_timeout+0x68/0xf4 [<c06e78e0>] (set_data_timeout+0x0/0xf4) from [<c06e7dc8>] (omap_hsmmc_request+0x2d0/0x5c8) r8:efa78400 r7:00000001 r6:00000000 r5:ef9efe78 r4:efa78640 r3:ef9efee4 [<c06e7af8>] (omap_hsmmc_request+0x0/0x5c8) from [<c06df040>] (mmc_wait_for_req+0x118/0x130) [<c06def28>] (mmc_wait_for_req+0x0/0x130) from [<c06e59e8>] (mmc_blk_issue_rq+0x1c0/0x500) r6:ef86f000 r5:efa79000 r4:c91e61a0 [<c06e5828>] (mmc_blk_issue_rq+0x0/0x500) from [<c06e6620>] (mmc_queue_thread+0xf4/0xf8) [<c06e652c>] (mmc_queue_thread+0x0/0xf8) from [<c045ddec>] (kthread+0x84/0x8c) [<c045dd68>] (kthread+0x0/0x8c) from [<c044b748>] (do_exit+0x0/0x604) r7:00000013 r6:c044b748 r5:c045dd68 r4:ef8d5d68 Code: e1a00004 e89da8f0 c0a653c0 e1a0c00d (e92dd818) ---[ end trace 533b4c955f5abafd ]--- > > > - Paul -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
