Hi, I just posted a guide on this topic on this group that I think that it will help you. Read it and let me know if you have a question.
Τη Παρασκευή, 9 Ιουνίου 2017 - 2:09:33 μ.μ. UTC+3, ο χρήστης [email protected] έγραψε: > > Hello, Vladimir. I am a student of computer engineering with some problems > to multiplex my BeagleBoard xM. How did you edit your device tree? I feel > like I'm at the very beginning of what I need to know to make my GPIO work, > but I'd be grateful for any help your experience might bring me. > > Thank you. > > Em sexta-feira, 15 de novembro de 2013 13:22:26 UTC-2, porkupan escreveu: >> >> On 3.12 an attempt to dump >> */sys/kernel/debug/pinctrl/48002030.pinmux/pins* continues to cause a >> kernel crash (not a complete crash, but bad enough): >> >> root@arm:~# cat /sys/kernel/debug/pinctrl/48002030.pinmux/pins >> Segmentation fault >> >> http://paste.ubuntu.com/6421695/ >> >> [63418.031249] Unhandled fault: external abort on non-linefetch (0x1028) >> at 0xfa002268 >> [63418.039337] Internal error: : 1028 [#1] SMP ARM >> [63418.044128] Modules linked in: ftdi_sio smsc95xx usbnet usbserial >> joydev leds_pwm rtc_twl uio_pdrv_genirq gpio_keys phy_generic uio >> [63418.056762] CPU: 0 PID: 1798 Comm: cat Not tainted 3.12.0-armv7-x8 #2 >> [63418.063537] task: de739600 ti: df082000 task.ti: df082000 >> [63418.069244] PC is at pcs_readw+0x0/0x10 >> [63418.073303] LR is at pcs_pin_dbg_show+0x2c/0x4c >> [63418.078094] pc : [<c0393d40>] lr : [<c0394a14>] psr: a0000013 >> [63418.078094] sp : df083ee0 ip : 00000000 fp : c0961fb5 >> [63418.090209] r10: de16088c r9 : c077a5e8 r8 : de1608b8 >> [63418.095703] r7 : 0000011c r6 : df566a00 r5 : 0000011c r4 : df566a00 >> [63418.102600] r3 : c0393d40 r2 : fa002030 r1 : df566a00 r0 : fa002268 >> [63418.109466] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM >> Segment user >> [63418.117004] Control: 10c5387d Table: 9db08019 DAC: 00000015 >> [63418.123046] Process cat (pid: 1798, stack limit = 0xdf082248) >> [63418.129119] Stack: (0xdf083ee0 to 0xdf084000) >> [63418.133728] 3ee0: de160880 0000011c df566a00 c038ef24 c038ee88 >> 00000000 df083f20 df566a00 >> [63418.142364] 3f00: 00000001 00010000 000cf000 df083f80 dd9f1e40 >> c0139e58 00000000 df566a28 >> [63418.151000] 3f20: 00000000 00000000 00000000 dd9f1e40 df083f80 >> dd9f1e40 000cf000 dd9f1e40 >> [63418.159606] 3f40: df082018 df083f80 00010000 00000000 00000000 >> c011c1f8 dd9f1e40 000cf000 >> [63418.168243] 3f60: 00000000 00000000 dd9f1e40 00000000 000cf000 >> 00010000 00000000 c011c914 >> [63418.176879] 3f80: 00000000 00000000 00010000 00010000 000171c4 >> 000cf000 00000003 c000da64 >> [63418.185516] 3fa0: df082000 c000d8e0 00010000 000171c4 00000003 >> 000cf000 00010000 000cf000 >> [63418.194122] 3fc0: 00010000 000171c4 000cf000 00000003 7fffe000 >> 00000000 00010000 00000000 >> [63418.202758] 3fe0: 00000000 bead0574 0000b581 b6ef6f2c 40000010 >> 00000003 ffffffeb ff7fdfbf >> [63418.211395] [<c0393d40>] (pcs_readw+0x0/0x10) from [<c0394a14>] >> (pcs_pin_dbg_show+0x2c/0x4c) >> [63418.220336] [<c0394a14>] (pcs_pin_dbg_show+0x2c/0x4c) from >> [<c038ef24>] (pinctrl_pins_show+0x9c/0xd0) >> [63418.230072] [<c038ef24>] (pinctrl_pins_show+0x9c/0xd0) from >> [<c0139e58>] (seq_read+0x1b0/0x404) >> [63418.239257] [<c0139e58>] (seq_read+0x1b0/0x404) from [<c011c1f8>] >> (vfs_read+0xa4/0x168) >> [63418.247711] [<c011c1f8>] (vfs_read+0xa4/0x168) from [<c011c914>] >> (SyS_read+0x38/0x68) >> [63418.256011] [<c011c914>] (SyS_read+0x38/0x68) from [<c000d8e0>] >> (ret_fast_syscall+0x0/0x30) >> [63418.264831] Code: e5d03000 e6ef0073 f57ff04f e12fff1e (e1d030b0) >> [63418.307189] ---[ end trace 12432e5fbd2a5e32 ]--- >> [63418.312133] In-band Error seen by MPU at address 0 >> [63418.317260] ------------[ cut here ]------------ >> [63418.322174] WARNING: CPU: 0 PID: 1798 at drivers/bus/omap_l3_smx.c:162 >> omap3_l3_app_irq+0xcc/0x110() >> [63418.331787] Modules linked in: ftdi_sio smsc95xx usbnet usbserial >> joydev leds_pwm rtc_twl uio_pdrv_genirq gpio_keys phy_generic uio >> [63418.344390] CPU: 0 PID: 1798 Comm: cat Tainted: G D >> 3.12.0-armv7-x8 #2 >> [63418.352233] [<c0014000>] (unwind_backtrace+0x0/0xdc) from [<c0010eb0>] >> (show_stack+0x10/0x14) >> [63418.361236] [<c0010eb0>] (show_stack+0x10/0x14) from [<c06febf0>] >> (dump_stack+0x70/0x8c) >> [63418.369781] [<c06febf0>] (dump_stack+0x70/0x8c) from [<c003b328>] >> (warn_slowpath_common+0x64/0x88) >> [63418.379241] [<c003b328>] (warn_slowpath_common+0x64/0x88) from >> [<c003b3dc>] (warn_slowpath_null+0x18/0x20) >> [63418.389434] [<c003b3dc>] (warn_slowpath_null+0x18/0x20) from >> [<c038e034>] (omap3_l3_app_irq+0xcc/0x110) >> [63418.399353] [<c038e034>] (omap3_l3_app_irq+0xcc/0x110) from >> [<c007b104>] (handle_irq_event_percpu+0x6c/0x1fc) >> [63418.409851] [<c007b104>] (handle_irq_event_percpu+0x6c/0x1fc) from >> [<c007b2d4>] (handle_irq_event+0x40/0x60) >> [63418.420227] [<c007b2d4>] (handle_irq_event+0x40/0x60) from >> [<c007dd2c>] (handle_level_irq+0xd4/0xfc) >> [63418.429840] [<c007dd2c>] (handle_level_irq+0xd4/0xfc) from >> [<c007a968>] (generic_handle_irq+0x20/0x30) >> [63418.439666] [<c007a968>] (generic_handle_irq+0x20/0x30) from >> [<c000e1c4>] (handle_IRQ+0x68/0x90) >> [63418.448944] [<c000e1c4>] (handle_IRQ+0x68/0x90) from [<c00085d8>] >> (omap3_intc_handle_irq+0x60/0x74) >> [63418.458496] [<c00085d8>] (omap3_intc_handle_irq+0x60/0x74) from >> [<c07038c0>] (__irq_svc+0x40/0x50) >> [63418.467956] Exception stack(0xdf083cd8 to 0xdf083d20) >> [63418.473266] >> 3cc0: df5ca9c4 >> 00003572 >> [63418.481903] 3ce0: df5ca4c0 00000504 df6cedc0 df082000 00000b58 >> 00000001 df082000 0000000b >> [63418.490539] 3d00: c0ac97b0 c0393d40 00000000 df083d20 c0095a4c >> c0095b54 40000113 ffffffff >> [63418.499176] [<c07038c0>] (__irq_svc+0x40/0x50) from [<c0095b54>] >> (acct_collect+0x19c/0x1a0) >> [63418.507995] [<c0095b54>] (acct_collect+0x19c/0x1a0) from [<c003d6c0>] >> (do_exit+0x1d0/0x940) >> [63418.516815] [<c003d6c0>] (do_exit+0x1d0/0x940) from [<c001115c>] >> (die+0x2a8/0x3a0) >> [63418.524810] [<c001115c>] (die+0x2a8/0x3a0) from [<c00083b8>] >> (do_DataAbort+0x84/0x98) >> [63418.533081] [<c00083b8>] (do_DataAbort+0x84/0x98) from [<c0703858>] >> (__dabt_svc+0x38/0x60) >> [63418.541778] Exception stack(0xdf083e98 to 0xdf083ee0) >> [63418.547119] >> 3e80: fa002268 >> df566a00 >> [63418.555755] 3ea0: fa002030 c0393d40 df566a00 0000011c df566a00 >> 0000011c de1608b8 c077a5e8 >> [63418.564361] 3ec0: de16088c c0961fb5 00000000 df083ee0 c0394a14 >> c0393d40 a0000013 ffffffff >> [63418.573028] [<c0703858>] (__dabt_svc+0x38/0x60) from [<c0393d40>] >> (pcs_readw+0x0/0x10) >> [63418.581359] [<c0393d40>] (pcs_readw+0x0/0x10) from [<c0394a14>] >> (pcs_pin_dbg_show+0x2c/0x4c) >> [63418.590270] [<c0394a14>] (pcs_pin_dbg_show+0x2c/0x4c) from >> [<c038ef24>] (pinctrl_pins_show+0x9c/0xd0) >> [63418.600036] [<c038ef24>] (pinctrl_pins_show+0x9c/0xd0) from >> [<c0139e58>] (seq_read+0x1b0/0x404) >> [63418.609222] [<c0139e58>] (seq_read+0x1b0/0x404) from [<c011c1f8>] >> (vfs_read+0xa4/0x168) >> [63418.617675] [<c011c1f8>] (vfs_read+0xa4/0x168) from [<c011c914>] >> (SyS_read+0x38/0x68) >> [63418.625946] [<c011c914>] (SyS_read+0x38/0x68) from [<c000d8e0>] >> (ret_fast_syscall+0x0/0x30) >> [63418.634735] ---[ end trace 12432e5fbd2a5e33 ]--- >> >> >> On Thursday, October 31, 2013 4:13:58 PM UTC-4, porkupan wrote: >>> >>> Well, so I think I understand a bit more about the DTS support for >>> GPIO. I configured the pinctrl for GPIO5 channel, and it seems to have >>> some effect on the GPIO pins. After the kernel starts up the LEDs are >>> being turned off. >>> >>> &omap3_pmx_core { >>> vvv_gpio_pins: pinmux_gpio_pins { >>> pinctrl-single,pins = < >>> 0x136 (PIN_OUTPUT | MUX_MODE4) /* >>> gpio_137 */ >>> 0x138 (PIN_OUTPUT | MUX_MODE4) /* >>> gpio_138 */ >>> 0x13a (PIN_OUTPUT | MUX_MODE4) /* >>> gpio_139 */ >>> >; >>> }; >>> }; >>> >>> &gpio5 { >>> pinctrl-names = "default"; >>> pinctrl-0 = <&vvv_gpio_pins>; >>> }; >>> >>> However the GPIO export mechanism from userspace is still not working. >>> Basically, no matter what value you try to set gpio137-139, they stay low >>> (although the value in the /sys/class/gpio/gpioXXX/value file is being >>> changed appropriately. It's as if gpiochip128 is not really associated >>> with gpio5. >>> >>> I am also worried about not being able to dump >>> */sys/kernel/debug/pinctrl/48002030.pinmux/pins* . The kernel hiccup >>> occurs on the base 3.11 DTB file, so it's not my change that's causing it. >>> >>> >>> >>> On Friday, October 25, 2013 3:13:46 PM UTC-4, porkupan wrote: >>>> >>>> Trying to dump the pinmux states >>>> (/sys/kernel/debug/pinctrl/48002030.pinmux/pins) in 3.11 seems to cause a >>>> kernel crash: >>>> http://paste.ubuntu.com/6302171/ >>>> >>>> GPIO access via /sys/class/gpio appears to be nonoperational in 3.11. >>>> It looks like a reasonable assumption that GPIOs may not be muxed into the >>>> GPIO pins. >>>> >>>> I tried to add a devicetree entry to to force-mux GPIOs: >>>> >>>> &omap3_pmx_core { >>>> vvv_gpio_pins: pinmux_gpio_pins { >>>> pinctrl-single,pins = < >>>> 0x134 (PIN_OUTPUT | MUX_MODE4) /* >>>> gpio_137 */ >>>> 0x135 (PIN_OUTPUT | MUX_MODE4) /* >>>> gpio_138 */ >>>> 0x136 (PIN_OUTPUT | MUX_MODE4) /* >>>> gpio_139 */ >>>> >; >>>> }; >>>> }; >>>> >>>> &ocp { >>>> gpio_helper: helper { >>>> compatible = "ti,omap3-gpio"; >>>> pinctrl-names = "default"; >>>> pinctrl-0 = <&vvv_gpio_pins>; >>>> status = "okay"; >>>> }; >>>> }; >>>> >>>> Doesn't seem to do anything. The only indication that the kernel is >>>> actually trying to parse the fake "helper" device is these lines in the >>>> message log: >>>> >>>> [ 0.369201] omap_gpio helper.26: could not find pctldev for node >>>> /ocp/pinmux@48002030/pinmux_gpio_pins, deferring probe >>>> [ 0.369232] platform helper.26: Driver omap_gpio requests probe deferral >>>> <...> >>>> [ 3.354125] omap_gpio helper.26: Invalid IRQ resource >>>> >>>> Obviously, I have no idea what "compatible" driver should I chose, >>>> omap3_gpio just sounded like something that could fit. For BBB they >>>> reference bone-pinmux-helper, which I assume is BBB-specific? >>>> >>>> Thanks! >>>> >>>> -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/8b2de04c-a2ef-48ad-bf91-713aa17d5e63%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
