-- File: yse5250.devs

local Hw = Io.Hw
local Res = Io.Res

Io.hw_add_devices
{
	UART3 = Hw.Device
	{
		hid = "UART3";
		Res.irq(86);
		Res.mmio(0x12C30000, 0x12C3ffff);
	}
}

-- File: yse5250.io

Io.add_vbusses
{
	-- Create a virtual bus for a client and give access to UART3
	uart03 = Io.Vi.System_bus(function ()
		dev = wrap(Io.system_bus():match("UART3"));
	end);
}

-- gps-drv.cfg

-- Run GPS Driver for YSE5250 (Exynos 5250)

require("L4");

-- Shortcuts
local ld = L4.default_loader;

local vbus_uart03 = ld:new_channel();
local platform_ctl = ld:new_channel();
local gps_srv = ld:new_channel();

-- Start the IO Server
ld:start(
{
	caps = {
		sigma0  	 = L4.cast(L4.Proto.Factory, L4.Env.sigma0):create(L4.Proto.Sigma0);
		icu 		 = L4.Env.icu;
		platform_ctl = platform_ctl:svr();
		uart03   	 = vbus_uart03:svr();
	},
	log = { "IO Server", "green" },
	l4re_dbg = L4.Dbg.Warn,
}, "rom/io rom/yse5250.devs rom/yse5250.io");

-- Start the GPS Driver Server conected to UART3
ld:start(
{ 
	caps = { 
		gps_srv = gps_srv:svr();
		vbus =  vbus_uart03; 
	},
    log = {"GPS Driver","blue"} 
}, "rom/gps_drv");

/pkg/serial-drv/server/src/main.cc

Message: 1
Date: Fri, 17 Apr 2015 12:03:46 +0200
From: "Pflaum, Clemens" <clemens.pflaum@mytum.de>
To: l4-hackers@os.inf.tu-dresden.de
Subject: Using a second UART to control a serial device
Message-ID: <4a79357eec3b3359e8b09e16a3fe0994@roundcube.lrz.de>
Content-Type: text/plain; charset=US-ASCII; format=flowed

Hi L4 Hackers,
Im currently running Fiasco.OC with L4Re on my BananaPi. I'm trying to 
control a serial device (Pololu Servo Controller) by sending a small 
series of Bytes over a second UART ( not UART 0 since im getting the 
console from there ). Via documentation I've found out that UART 3 is at 
0x01C28C00 and is a U6_16550A, so I'm hoping the driver  in 
/pkg/drivers-frst/uart/src/uart_pxa.cc will be compatible with that.
Where and how would I have to go about initiating my UART 3? By writing 
a new platform for BPi in /pkg/bootstrap/server/src/platform? The 
function set_stdio_uart(&_uart); made me think its only the "console" 
UART. Or do I have to instantiate some kind of Hw.Device like the gpio 
in /pkg/io/config/arm-omap3.devs and put it on a new vBus like in 
/pkg/io/doc/example.io ?

Or am I thinking way too complicated and it is as simple as editing the 
/pkg/serial-drv/server/src/main.cc :

bool
Serial_drv::init()
{
   int irq_num = 37;                                                      
         // How can i find out what this number refers to/do i have to 
change it at all?
   l4_addr_t phys_base = 0x1000a000;                                      
         // change to 0x01C28C00
#if 0
   int irq_num = 74;
   l4_addr_t phys_base = 0x49020000;
#endif
   l4_addr_t virt_base = 0;

   if (l4io_request_iomem(phys_base, 0x1000, L4IO_MEM_NONCACHED, 
&virt_base))
     {
       printf("serial-drv: request io-memory from l4io failed.\n");
       return false;
     }
   printf("serial-drv: virtual base at:%lx\n", virt_base);

   L4::Io_register_block_mmio *regs = new 
L4::Io_register_block_mmio(virt_base);
   _uart = new (malloc(sizeof(L4::Uart_pl011))) L4::Uart_pl011(24019200); 
                    //change to L4::Uart_pxa(what does this number mean?)
   _uart->startup(regs);


Thanks for any answers in advance.

Regards,
Clemens            c...@mytum.de

-- 
Lic. Reinier Millo Sánchez
Centro de Estudios de Informática
Universidad Central "Marta Abreu" de Las Villas
Carretera a Camajuaní Km 5 1/2
Santa Clara, Villa Clara, Cuba
CP 54830

"antes de discutir ... respira;
  antes de hablar ... escucha;
 antes de escribir ... piensa;
  antes de herir ... siente;
 antes de rendirte ... intenta;
  antes de morir ... vive"