[LinuxBIOS] Accessing MCP55 internal serial UART, GPIOs
eswierk at arastra.com
Wed Mar 14 18:47:00 CET 2007
After staring at the code for a while I realized that I wasn't mapping
the GPIO registers into IO space properly. (I'm still using the ck804
code with a bunch of hacks, as I haven't had time to integrate the
mcp55 support, but there are indeed some important differences :-)
I changed ck804_early_set_port() to use the proper device ID and
function (1:1, not 1:0), and now both the serial port and the LEDs
Now I'm fantasizing about using gdb to step my way through the rest of
the code, which hangs somewhere after ck804_early_setup_x(). When I
set CONFIG_GDB_STUB=1 and add a call to gdb_stub_breakpoint(), I get a
cache_as_ram_auto.c:8740: undefined reference to `gdb_stub_breakpoint'
What's the right magic to export the gdb_stub_breakpoint symbol from c_start.S?
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