L4Re GPIO

Adam Lackorzynski adam at os.inf.tu-dresden.de
Thu Dec 4 23:53:01 CET 2014


Hi,

On Thu Dec 04, 2014 at 14:57:14 +0700, Erry Pradana Darajati wrote:
> I have some follow up question from my last email.
> 
> 1. About GPIO. So IOs defined on LUA script. So in OMAP4460, is gonna be
> like this, isn't it ?

Principally yes.

>     I have a question in line of this code.
> 
> GPIO = Hw.Device(function()
>     GPIO1 = Hw.Gpio_omap46x_chip(function(
> )
>       hid = "gpio-omap46x-GPIO1";
>       compatible = {"ti,omap4-gpio"};
>       regs = Res.mmio(0x4A310000, 0x4A310194); // This one is range of
> Address GPIO1 used

Yes.

>       irq = Res.irq(29); //This one is IRQ of GPIO1 ? What is the meaning
> of irq(29) ?

This is the IRQ number for the GPIO chip. The driver in IO will then
generate IRQs for the specific pins by reading hardware registers of the
GPIO chip.

>       scm_table = 0; // I still don't understand about this line

This selects the specific GPIO block. It is a driver-internal selection.

>     end);
> end);
> 
> And where can i read the reference about another parameters of this ? (Like
> there pins parameter in raspi b. And there are mems instead of regs)

The specific ones are driver specific so you should check the driver in
io (pkg/io/server/src/drivers/gpio/*).

I guess a driver for the 4460 won't be so different from the omap3 one
so maybe it can be modified.

> 2. I try the L4Re with x86 build run in QEMU. And want it to accept my
> keyboard input. So i need to include x86-legacy.devs module in modules.list
> and define REQUIRES_LIBS=libc_be_file_stdin isn't it ?
> But after i've done it, it still doesn't accept keyboard input. what did i
> miss ?

For what purpose do you want it to accept input? Maybe just a missing
-serial_esc option on Fiasco's command line?




Adam
-- 
Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/



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