Tool/software: Linux
On our custom board, we want to use GPIO3 as output io. the insmod modules is failed when we configure the GPIO_OE register in modules.
the message is:
[ 1356.253828] en phyaddr is:0x48057134 viraddr is:0xfa057134
[ 1356.260474] Unhandled fault: asynchronous external abort (0x1211) at 0x00000000
[ 1356.260477] pgd = ed35d7c0
[ 1356.260483] [00000000] *pgd=acf2c003, *pmd=fe37f003
[ 1356.260489] Internal error: : 1211 [#1] PREEMPT SMP ARM
[ 1356.260568] Modules linked in: ubt_sci(O+) xhci_plat_hcd xhci_hcd usbcore xfrm_user xfrm4_tunnel ipcomp xfrm_ipcomp esp4 ah4 bluetooth af)
[ 1356.260575] CPU: 1 PID: 1136 Comm: insmod Tainted: G W O 4.4.41-rt50-g968d071ce9 #9
[ 1356.260578] Hardware name: Generic DRA74X (Flattened Device Tree)
[ 1356.260581] task: ed25ba00 ti: ecdae000 task.ti: ecdae000
when we use 'devmem2' to read GPIO_OE '0x48057134', the linux print message as:
root@am57xx-evm:/mnt# devmem2 0x48057134
/dev/mem opened.
Memory mapped at address 0xb6f02000.[ 1783.180811] Unhandled fault: asynchronous external abort (0x1211) at 0x00000000
[ 1783.180814] pgd = ed358980
[ 1783.180817] ------------[ cut here ]------------
[ 1783.180828] [00000000] *pgd=ad1ec003, *pmd=fe04b003
[ 1783.204974] WARNING: CPU: 1 PID: 28 at drivers/bus/omap_l3_noc.c:147 l3_interrupt_handler+0x25c/0x36c()
[ 1783.214579] 44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER1_P3 (Read): Data Access in User mode during Functional access
[ 1783.226202] Modules linked in:Bus error (core dumped) ubt_sci(O+) xhci_plat_hcd xhci_hcd usbcore xfrm_user xfrm4_tunnel ipcomp xfrm_ipcom)
[ 1783.282665] CPU: 1 PID: 28 Comm: irq/23-l3-app-i Tainted: G D W O 4.4.41-rt50-g968d071ce9 #9
[ 1783.282668] Hardware name: Generic DRA74X (Flattened Device Tree)
[ 1783.282672] Backtrace:
[ 1783.282688] [<c0013100>] (dump_backtrace) from [<c00132fc>] (show_stack+0x18/0x1c)
[ 1783.282698] r7:c02e7a0c r6:20080013 r5:00000000 r4:c093e2b4
[ 1783.282708] [<c00132e4>] (show_stack) from [<c02bb384>] (dump_stack+0x8c/0xa0)
[ 1783.282718] [<c02bb2f8>] (dump_stack) from [<c0034794>] (warn_slowpath_common+0x88/0xb8)
[ 1783.282725] r7:c02e7a0c r6:00000093 r5:00000009 r4:ee651e28
[ 1783.282735] [<c003470c>] (warn_slowpath_common) from [<c00347fc>] (warn_slowpath_fmt+0x38/0x40)
[ 1783.282743] r8:ee62e510 r7:c0828920 r6:00000002 r5:c08289e0 r4:c0828a84
[ 1783.282751] [<c00347c8>] (warn_slowpath_fmt) from [<c02e7a0c>] (l3_interrupt_handler+0x25c/0x36c)
[ 1783.282755] r3:ee62e380 r2:c0828a84
[ 1783.282758] r4:80080003
[ 1783.282767] [<c02e77b0>] (l3_interrupt_handler) from [<c00839d4>] (irq_forced_thread_fn+0x28/0x7c)
[ 1783.282777] r10:c00839ac r9:ee62e8c0 r8:ee601900 r7:00000001 r6:00000000 r5:ee601900
[ 1783.282779] r4:ee62e8c0
[ 1783.282788] [<c00839ac>] (irq_forced_thread_fn) from [<c0083d3c>] (irq_thread+0x124/0x1f8)
[ 1783.282794] r7:00000001 r6:00000000 r5:ee650000 r4:ee62e8e4
[ 1783.282802] [<c0083c18>] (irq_thread) from [<c00507cc>] (kthread+0xe4/0xfc)
[ 1783.282811] r10:00000000 r9:00000000 r8:00000000 r7:c0083c18 r6:ee62e8c0 r5:ee62e900
[ 1783.282813] r4:00000000
[ 1783.282821] [<c00506e8>] (kthread) from [<c000fb10>] (ret_from_fork+0x14/0x24)
[ 1783.282827] r7:00000000 r6:00000000 r5:c00506e8 r4:ee62e900
[ 1783.282830] ---[ end trace 0000000000000008 ]---
it seems that the register was protected. how can i restore this problem?
the linux version is: am57xx-evm 4.4.41-rt50-g968d071ce9
