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void uhci_init() {
	
	asm("movw %%ds, %%ax":"=a"(ds));

	unsigned int   i;
	unsigned char bus  = usb_pack[0x12];
	unsigned char dev  = usb_pack[0x13];
	unsigned char func = usb_pack[0x14];
	unsigned char reset = 0;	
	printk(" Initializing UHCI USB Device Driver ...\n");

	// I: Initialize Descriptors:
	// ----------------------------
	//printk(" Port 0: %x\n", usbio.readregw(UHCI_REG_PORTBASE + 0));
	//printk(" Port 1: %x\n", usbio.readregw(UHCI_REG_PORTBASE + 2));
	
	// 1- Pointers:
	uhci_frlst = (unsigned int   *)((unsigned int)(uhci_data  + 0x0FFF) & 0xFFFFF000);
	uhci_qhlst = (eightbytelen   *)((unsigned int) uhci_frlst + 0x1000);
	uhci_tdlst = (sixteenbytelen *)((unsigned int) uhci_qhlst + 0x0010);

	// 2- TDs:
	uhci_tdlst[0].lng[0] = 0x00000001;
	uhci_tdlst[0].lng[1] = 0x00000000;
	uhci_tdlst[0].lng[2] = 0x00000000;
	uhci_tdlst[0].lng[3] = 0x00000000;
	
	// 3- QHs:
	uhci_qhlst[0].lng[0] = ((unsigned int) &uhci_qhlst[1] + krnl_get_selector_base(ds)) | 0x00000002;
	uhci_qhlst[0].lng[1] = 0x00000001;
	uhci_qhlst[1].lng[0] = 0x00000001;
	uhci_qhlst[1].lng[1] = ((unsigned int) &uhci_tdlst[0] + krnl_get_selector_base(ds)) | 0x00000000;

	// 4- Frame List:
	for (i = 0; i < 0x400; i++)
		uhci_frlst[i] = ((unsigned int) &uhci_qhlst[0] + krnl_get_selector_base(ds)) | 0x00000002;
		
	// II: Initialize Structures:
	// ----------------------------
	unsigned char *struct_ptr = (unsigned char *) &uhci_devices;
	for (i = 0; i < sizeof(uhci_devices); i++) struct_ptr[i] = 0;
	
	// III: Initialize UHCI:
	// ----------------------------
	// 1- Set Bus Master and I/O Space Enable Bits.
	unsigned int pci_command;
	pci_command = pci_readw(bus, dev, func, 4);
	pci_writew(pci_command | 5, bus, dev, func, 4);
	
	// 2- Turn off PIRQ and disable SMI. this shall turn off BIOS's legacy support.
   	pci_writew(0x8f00, bus, dev, func, 0xC0);
	
	// 3- Reset the host controller:
	usbio.writeregw(2, UHCI_REG_USBCMD);
	while(usbio.readregw(UHCI_REG_USBCMD) & 2);
	sleep(1000); // Sleep for 1 second.
	
	// 4- Setup Registers:
	usbio.writeregb(64, UHCI_REG_SOFMOD); // 64+11936=12000. (1ms for each frame).
	usbio.writeregl((unsigned int) uhci_frlst + krnl_get_selector_base(ds), UHCI_REG_FRBASEADD);
	usbio.writeregw(0x00, UHCI_REG_FRNUM);  // Frame Number
	usbio.writeregw(0x01, UHCI_REG_USBCMD); // RUN

	// IV: Search for Connected Devices:
	// -----------------------------------
	for (i = 0; i < 2; i++) {
		unsigned int portsc = usbio.readregw(UHCI_REG_PORTBASE + (2*i));
		while (portsc & 1) {
			// Set Reset Bit:
			usbio.writeregw(0x0200, UHCI_REG_PORTBASE + (2*i)); // Reset
			sleep(500);			
			usbio.writeregw(0x0000, UHCI_REG_PORTBASE + (2*i)); // Stop Reset
			sleep(100);
			usbio.writeregw(0x000E, UHCI_REG_PORTBASE + (2*i)); // Enable
			sleep(500);
		
			if (!uhci_enumerate(i)) break;
		}
	}
}

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I'm just starting my UHCI driver at the moment, and the first thing that's worrying me is that there are lots of UHCI controllers in every system. The driver will need coding carefully so it can handle multiple devices

Code: Select all

I'm just starting my UHCI driver at the moment,