On a TI am3359 processor (Beaglebone Black) I'm attempting to attempting
to control the GPIO pin-muxing through the Control subsystem registers
which start at 0x4e100000. I can read and write to the GPIO0 through
GPIO3 registers correctly through MMIO after attaching the device
memory, but when I try to write to any of the pin mux registers nothing
is written and no errors are output.
The code I've written to set up pin muxing resides in a gpio driver
which is a modified version of an am 33xx gpio driver I pulled from the
ksyslabs.org repository.
With verbosity turned on, I see the that the pin mux registers are
attached to local memory:
/Genode::Io_mem_session_component::Dataspace_attr
Genode::Io_mem_session_component::_prepare_io_mem(const char*,
Genode::Range_allocator*): I/O mem [44e10000,44e11000)//
//[init -> gpio_drv] GPIO_control base is 0x44e10000 local is 0x4000/
I write a value of 5 to the register offset 0x800 into the Control
dataspace:
/[init -> gpio_drv] mmio write 0x4800: 0x00000005//
//[init -> gpio_drv] void Omap_driver::set_pin_controls(int, int, int):
B=1, P=0, Mode=5, Input=0, Offset=0/
In jdb I see that the value at 0x4800 has not changed after apparently
writing 5 to it.
I believe I've set up the IO memory mapping correctly, the values read
from the pin muxing registers look correct, and the GPIO subsystem
appears to be set up correctly as I can turn on and off some LEDs.
Is there something I need to do to enable writing to the memory region
containing the Control registers?
Thanks for any help.
Bob Stewart
------------------------------------------------------------------------------
October Webinars: Code for Performance
Free Intel webinars can help you accelerate application performance.
Explore tips for MPI, OpenMP, advanced profiling, and more. Get the most from
the latest Intel processors and coprocessors. See abstracts and register >
http://pubads.g.doubleclick.net/gampad/clk?id=60135991&iu=/4140/ostg.clktrk
_______________________________________________
Genode-main mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/genode-main
