I'm trying to get the MMC port working on our custom AM3352 CPU board. I have added MMC entries to out dts file (similar to [1]), and I've enabled CONFIG_TI_EDMA. Our board boots fine without an SD card inserted ... [ 0.000000] Booting Linux on physical CPU 0x0 [ 0.000000] Linux version 3.11.0-rc1-00025-g95b9b72 (mpfj@mpfj-nanobone) (gcc version 4.6.3 (Buildroot 2013.02-dirty) ) #309 Wed Jul 17 16:37:28 BST 2013 ... [ 2.789028] VFS: Mounted root (ubifs filesystem) on device 0:12. [ 2.797268] devtmpfs: mounted [ 2.801032] Freeing unused kernel memory: 200K (c0551000 - c0583000) ... Welcome to Buildroot nanobone login: But when I boot with a card already inserted, I get the following oops ... ... [ 1.827343] Unable to handle kernel NULL pointer dereference at virtual address 0000000c [ 1.835868] pgd = c0004000 [ 1.838774] [0000000c] *pgd=00000000 [ 1.842556] Internal error: Oops: 5 [#1] ARM [ 1.847063] CPU: 0 PID: 6 Comm: kworker/u2:0 Not tainted 3.11.0-rc1-00025-g95b9b72 #309 [ 1.855511] Workqueue: kmmcd mmc_rescan [ 1.859556] task: cf06a080 ti: cf072000 task.ti: cf072000 [ 1.865257] PC is at omap_hsmmc_start_command+0x74/0xf4 [ 1.870761] LR is at omap_hsmmc_request+0xec/0x4dc [ 1.875806] pc : [<c0305b70>] lr : [<c0306c64>] psr: 60000113 [ 1.875806] sp : cf073ca0 ip : 00000000 fp : 00000008 [ 1.887885] r10: cf073de8 r9 : 00000001 r8 : cf11d918 [ 1.893382] r7 : 00000003 r6 : cf33cc80 r5 : 00000001 r4 : 00000033 [ 1.900250] r3 : 00020000 r2 : cf073db8 r1 : cf073d84 r0 : cf33cc80 [ 1.907122] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel [ 1.914813] Control: 10c5387d Table: 80004019 DAC: 00000015 [ 1.920859] Process kworker/u2:0 (pid: 6, stack limit = 0xcf072238) [ 1.927454] Stack: (0xcf073ca0 to 0xcf074000) [ 1.932048] 3ca0: cf33c800 cf073d40 00000003 00000000 c0076a8c cf073d40 48060220 48060220 [ 1.940659] 3cc0: 00000004 00000004 00000002 00000002 cf073ec8 c0421a9c c051835c cf073d40 [ 1.949271] 3ce0: cf33c800 00000001 00000008 00000008 00000002 cf073db8 cf073ec8 c02f0f28 [ 1.957882] 3d00: 00000200 00000064 00000000 cf073db8 cf073ec8 cf073d40 cf073d50 00000000 [ 1.966493] 3d20: cf33c800 c02f18a4 cf369800 cf369a80 00000000 cf360880 00000008 c02f9964 [ 1.975104] 3d40: 00000000 cf073d84 cf073db8 00000000 00000001 00000001 dead4ead ffffffff [ 1.983717] 3d60: ffffffff c0af722c c06aa3e4 00000000 c04ddadc cf073d74 cf073d74 c02f0dc4 [ 1.992327] 3d80: 00000000 00000033 00000000 00000000 00000000 00000000 00000000 000000b5 [ 2.000938] 3da0: 00000000 00000000 00000000 00000000 cf073db8 cf073d40 05f5e100 00000000 [ 2.009548] 3dc0: 00000008 00000001 00000000 00000200 00000000 00000000 cf073d40 00000001 [ 2.018159] 3de0: cf073de8 00000000 c0cf1c02 00000880 00000008 8f360880 00000000 cf369800 [ 2.026771] 3e00: cf33c800 00000000 cf369800 cf073e4c cf072000 c02f8740 00000000 00000015 [ 2.035382] 3e20: 00000003 cf33c800 00000000 00000000 cf369800 cf073e4c cf072000 c02f8b20 [ 2.043994] 3e40: 00000002 c02f25cc 00000002 02544d53 41303447 1026c914 2600bbbd c0ff8000 [ 2.052605] 3e60: c0455884 cf33c800 00000000 c0455884 c0455890 00000000 cf072000 c02f92bc [ 2.061217] 3e80: c0455890 00ff8000 00000002 cf33cb14 cf33c800 c02f3a28 cf041ac0 cf33cb14 [ 2.069829] 3ea0: cf050c00 cf051c00 00000000 c00507ec 00000002 00000000 c0050778 c0050f10 [ 2.078441] 3ec0: 00000000 00000000 c0af7268 c06aa1c4 00000000 c0518cd0 cf06a080 cf041ac0 [ 2.087054] 3ee0: cf050c00 cf072000 cf050c30 cf041ad8 00000089 c05d7b5c cf050c00 c0050e4c [ 2.095665] 3f00: 00000000 cf072000 60000113 cf04dda8 00000000 cf041ac0 c0050d08 00000000 [ 2.104276] 3f20: 00000000 00000000 00000000 c0056c94 c0429a18 00000000 00000001 cf041ac0 [ 2.112888] 3f40: 00000000 00000001 dead4ead ffffffff ffffffff c05ec0a0 00000000 00000000 [ 2.121499] 3f60: c04ddadc cf073f64 cf073f64 00000000 00000001 dead4ead ffffffff ffffffff [ 2.130112] 3f80: c05ec0a0 00000000 00000000 c04ddadc cf073f90 cf073f90 cf073fac cf04dda8 [ 2.138724] 3fa0: c0056bf0 00000000 00000000 c0013588 00000000 00000000 00000000 00000000 [ 2.147334] 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [ 2.155946] 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 57e0c5db 5ffb7d3c [ 2.164565] [<c0305b70>] (omap_hsmmc_start_command+0x74/0xf4) from [<00000003>] (0x3) [ 2.172814] Code: 13a03801 0a00001b e590c008 e5914000 (e59cc00c) [ 2.179314] ---[ end trace 6ec9899a56aef6aa ]--- I have also noticed that when the kernel boots okay (without a card inserted), if I then insert a card, nothing happens (even with CONFIG_MMC_DEBUG=y) ... including no kernel oops. Can anyone shed light on what's wrong ? Cheers Mark J. [1] https://lkml.org/lkml/2013/6/25/784 -- 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
