<font size="4">kernel version is linux-2.6.33 , and apply with android patch, hardware is arm realview pbxA9<br><br>I configured the sd/mmc driver into the kernel, when I boot filesystem from nfs, after the kernel boot up, the sd/mmc driver is probe ok, and I can mount the sd card. but when I copy the filesytem to sd/mmc card , and boot with it, it can't works ok. error as follows:<br>
</font><br><7>mmc0: starting CMD51 arg 00000000 flags 000000b5<br><7>mmc0: blksz 8 blocks 1 flags 00000200 tsac 100 ms nsac 0<br>Desc_No: 0 , desc0: 0x8000001c, desc1: 0x8, desc2: 0x7f3fe4e0, desc3: 0x0<br>
[ 55.324953] Desc_No: 0 , desc0: 0x8000001c, desc1: 0x8, desc2: 0x7f3fe4e0, desc3: 0x0<br><3>ns2416-sdmmc ns2416-sdmmc.0: MMC IRQ 00000004 (CMD 51): [ 55.365066] ns2416-sdmmc ns2416-sdmmc.0: MMC IRQ 00000004 (CMD 51): CMD doneCMD done<br>
<br><6>scsi0 : pata_platform<br>.......................................................................................<br>.......................................................................................<br><4>atkbd.c: keyboard reset failed on fpga:kmi1<br>
[ 53.382712] atkbd.c: keyboard reset failed on fpga:kmi1<br><6>Waiting for root device /dev/mmcblk0p4...<br>[ 53.861013] Waiting for root device /dev/mmcblk0p4...<br><3>INFO: task kmmcd:165 blocked for more than 120 seconds.<br>
[ 288.385908] INFO: task kmmcd:165 blocked for more than 120 seconds.<br><3>"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.<br>[ 288.425467] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.<br>
<6>kmmcd D[ 288.454402] kmmcd D<c> c02c69b4 c02c69b4 <c> 0 165 2 0x00000000<br> 0 165 2 0x00000000<br>[<c02c69b4>] (schedule+0x280/0x2c4) from [<c02c6b5c>] (schedule_timeout+0x18/0x188)<br>
[ 288.508780] [<c02c69b4>] (schedule+0x280/0x2c4) from [<c02c6b5c>] (schedule_timeout+0x18/0x188)<br>[<c02c6b5c>] (schedule_timeout+0x18/0x188) from [<c02c6628>] (wait_for_common+0xc0/0x14c)<br>[ 288.559151] [<c02c6b5c>] (schedule_timeout+0x18/0x188) from [<c02c6628>] (wait_for_common+0xc0/0x14c)<br>
[<c02c6628>] (wait_for_common+0xc0/0x14c) from [<c017b95c>] (mmc_wait_for_req+0x114/0x120)<br>[ 288.611389] [<c02c6628>] (wait_for_common+0xc0/0x14c) from [<c017b95c>] (mmc_wait_for_req+0x114/0x120)<br>
[<c017b95c>] (mmc_wait_for_req+0x114/0x120) from [<c017e1a4>] (mmc_app_send_scr+0xec/0x134)<br>[ 288.664140] [<c017b95c>] (mmc_wait_for_req+0x114/0x120) from [<c017e1a4>] (mmc_app_send_scr+0xec/0x134)<br>
[<c017e1a4>] (mmc_app_send_scr+0xec/0x134) from [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c)<br>[ 288.717131] [<c017e1a4>] (mmc_app_send_scr+0xec/0x134) from [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c)<br>
[<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c) from [<c017dd04>] (mmc_attach_sd+0x104/0x180)<br>[ 288.769587] [<c017d8f0>] (mmc_sd_init_card+0x38c/0x69c) from [<c017dd04>] (mmc_attach_sd+0x104/0x180)<br>
[<c017dd04>] (mmc_attach_sd+0x104/0x180) from [<c017b7bc>] (mmc_rescan+0x1b0/0x23c)<br>[ 288.819924] [<c017dd04>] (mmc_attach_sd+0x104/0x180) from [<c017b7bc>] (mmc_rescan+0x1b0/0x23c)<br>[<c017b7bc>] (mmc_rescan+0x1b0/0x23c) from [<c00500ac>] (worker_thread+0x14c/0x1c4)<br>
[ 288.868745] [<c017b7bc>] (mmc_rescan+0x1b0/0x23c) from [<c00500ac>] (worker_thread+0x14c/0x1c4)<br>[<c00500ac>] (worker_thread+0x14c/0x1c4) from [<c0052e94>] (kthread+0x7c/0x84)<br>[ 288.916254] [<c00500ac>] (worker_thread+0x14c/0x1c4) from [<c0052e94>] (kthread+0x7c/0x84)<br>
[<c0052e94>] (kthread+0x7c/0x84) from [<c002a970>] (kernel_thread_exit+0x0/0x8)<br><br><br><font size="4">CMD51 is the first command which need transfer data from SD to memory. At normal working condition when I write DMA Descriptors address to register it's begin transfer data, but now it's blocked and it can't get the data tranfer over, timeout or any others interrupt. my programm flow as follows;<br>
<br> setup DMA descriptors---> wmb() ----> write DMA descriptors address to SD/MMC controller's regsiter and begin to transfer data<br><br>I don't how to relove this problem , anybody can help me ? thanks!</font><br>
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