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path: root/src/northbridge/amd/amdk8/incoherent_ht.c
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/*
 	This should be done by Eric
	2004.12 yhlu add multi ht chain dynamically support

*/
#include <device/pci_def.h>
#include <device/pci_ids.h>
#include <device/hypertransport_def.h>


/* We can reduce the size of code generated by romcc by
 * changing all of the fixed size types that live in registers
 * into simple unsigned variables. (ie s/uint8_t/unsigned/g)
 */
#ifndef K8_HT_FREQ_1G_SUPPORT
        #define K8_HT_FREQ_1G_SUPPORT 0
#endif

#ifndef K8_SCAN_PCI_BUS
	#define K8_SCAN_PCI_BUS 0
#endif

static inline void print_linkn_in (const char *strval, uint8_t byteval)
{
#if 1
#if CONFIG_USE_INIT
        printk_debug("%s%02x\r\n", strval, byteval); 
#else
        print_debug(strval); print_debug_hex8(byteval); print_debug("\r\n");
#endif
#endif
}

static uint8_t ht_lookup_capability(device_t dev, uint16_t val)
{
	uint8_t pos;
	uint8_t hdr_type;

	hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
	pos = 0;
	hdr_type &= 0x7f;

	if ((hdr_type == PCI_HEADER_TYPE_NORMAL) ||
	    (hdr_type == PCI_HEADER_TYPE_BRIDGE)) {
		pos = PCI_CAPABILITY_LIST;
	}
	if (pos > PCI_CAP_LIST_NEXT) {
		pos = pci_read_config8(dev, pos);
	}
	while(pos != 0) { /* loop through the linked list */
		uint8_t cap;
		cap = pci_read_config8(dev, pos + PCI_CAP_LIST_ID);
		if (cap == PCI_CAP_ID_HT) {
			uint16_t flags;

			flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
			if ((flags >> 13) == val) {
				/* Entry is a slave or host , success... */
				break;
			}
		}
		pos = pci_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
	}
	return pos;
}

static uint8_t ht_lookup_slave_capability(device_t dev)
{          
	return ht_lookup_capability(dev, 0); // Slave/Primary Interface Block Format
}

static uint8_t ht_lookup_host_capability(device_t dev)
{
        return ht_lookup_capability(dev, 1); // Host/Secondary Interface Block Format
}

static void ht_collapse_previous_enumeration(uint8_t bus)
{
	device_t dev;
	uint32_t id;

	/* Check if is already collapsed */
	dev = PCI_DEV(bus, 0, 0);
        id = pci_read_config32(dev, PCI_VENDOR_ID);
        if ( ! ( (id == 0xffffffff) || (id == 0x00000000) ||
            (id == 0x0000ffff) || (id == 0xffff0000) ) ) {
                     return;
        }

	/* Spin through the devices and collapse any previous
	 * hypertransport enumeration.
	 */
	for(dev = PCI_DEV(bus, 1, 0); dev <= PCI_DEV(bus, 0x1f, 0x7); dev += PCI_DEV(0, 1, 0)) {
		uint32_t id;
		uint8_t pos;
		uint16_t flags;
		
		id = pci_read_config32(dev, PCI_VENDOR_ID);
		if ((id == 0xffffffff) || (id == 0x00000000) ||
		    (id == 0x0000ffff) || (id == 0xffff0000)) {
			continue;
		}
#if 0
#if CK804_DEVN_BASE==0 
                //CK804 workaround: 
                // CK804 UnitID changes not use
                if(id == 0x005e10de) {
                        break;
                }
#endif
#endif
		
		pos = ht_lookup_slave_capability(dev);
		if (!pos) {
			continue;
		}

		/* Clear the unitid */
		flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
		flags &= ~0x1f;
		pci_write_config16(dev, pos + PCI_CAP_FLAGS, flags);
	}
}

static uint16_t ht_read_freq_cap(device_t dev, uint8_t pos)
{
	/* Handle bugs in valid hypertransport frequency reporting */
	uint16_t freq_cap;
	uint32_t id;

	freq_cap = pci_read_config16(dev, pos);
	freq_cap &= ~(1 << HT_FREQ_VENDOR); /* Ignore Vendor HT frequencies */

	id = pci_read_config32(dev, 0);

	/* AMD 8131 Errata 48 */
	if (id == (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_AMD_8131_PCIX << 16))) {
		freq_cap &= ~(1 << HT_FREQ_800Mhz);
	} 

	/* AMD 8151 Errata 23 */
	if (id == (PCI_VENDOR_ID_AMD | (PCI_DEVICE_ID_AMD_8151_SYSCTRL << 16))) {
		freq_cap &= ~(1 << HT_FREQ_800Mhz);
	} 
	
	/* AMD K8 Unsupported 1Ghz? */
	if (id == (PCI_VENDOR_ID_AMD | (0x1100 << 16))) {
#if K8_HT_FREQ_1G_SUPPORT == 1
	    	/* Supported starting with E0 */
		device_t dev_2 = PCI_DEV(0,0x18,2);
              	if(pci_read_config32(dev_2,0x9c) < 0x20f00) 
#endif
			freq_cap &= ~(1 << HT_FREQ_1000Mhz);
	}

	return freq_cap;
}
#define LINK_OFFS(CTRL, WIDTH,FREQ,FREQ_CAP) \
      (((CTRL & 0xff) << 24) | ((WIDTH & 0xff) << 16) | ((FREQ & 0xff) << 8) | (FREQ_CAP & 0xFF))

#define LINK_CTRL(OFFS)     ((OFFS >> 24) & 0xFF)
#define LINK_WIDTH(OFFS)    ((OFFS >> 16) & 0xFF)
#define LINK_FREQ(OFFS)     ((OFFS >> 8) & 0xFF)
#define LINK_FREQ_CAP(OFFS) ((OFFS) & 0xFF)

#define PCI_HT_HOST_OFFS LINK_OFFS(		\
		PCI_HT_CAP_HOST_CTRL,           \
		PCI_HT_CAP_HOST_WIDTH,		\
		PCI_HT_CAP_HOST_FREQ,		\
		PCI_HT_CAP_HOST_FREQ_CAP)

#define PCI_HT_SLAVE0_OFFS LINK_OFFS(		\
		PCI_HT_CAP_SLAVE_CTRL0,         \
		PCI_HT_CAP_SLAVE_WIDTH0,	\
		PCI_HT_CAP_SLAVE_FREQ0,		\
		PCI_HT_CAP_SLAVE_FREQ_CAP0)

#define PCI_HT_SLAVE1_OFFS LINK_OFFS(		\
		PCI_HT_CAP_SLAVE_CTRL1,         \
		PCI_HT_CAP_SLAVE_WIDTH1,	\
		PCI_HT_CAP_SLAVE_FREQ1,		\
		PCI_HT_CAP_SLAVE_FREQ_CAP1)

static int ht_optimize_link(
	device_t dev1, uint8_t pos1, unsigned offs1,
	device_t dev2, uint8_t pos2, unsigned offs2)
{
	static const uint8_t link_width_to_pow2[]= { 3, 4, 0, 5, 1, 2, 0, 0 };
	static const uint8_t pow2_to_link_width[] = { 0x7, 4, 5, 0, 1, 3 };
	uint16_t freq_cap1, freq_cap2;
	uint8_t width_cap1, width_cap2, width, old_width, ln_width1, ln_width2;
	uint8_t freq, old_freq;
	int needs_reset;
	/* Set link width and frequency */

	/* Initially assume everything is already optimized and I don't need a reset */
	needs_reset = 0;

	/* Get the frequency capabilities */
	freq_cap1 = ht_read_freq_cap(dev1, pos1 + LINK_FREQ_CAP(offs1));
	freq_cap2 = ht_read_freq_cap(dev2, pos2 + LINK_FREQ_CAP(offs2));

	/* Calculate the highest possible frequency */
	freq = log2(freq_cap1 & freq_cap2);

	/* See if I am changing the link freqency */
	old_freq = pci_read_config8(dev1, pos1 + LINK_FREQ(offs1));
	old_freq &= 0x0f;
	needs_reset |= old_freq != freq;
	old_freq = pci_read_config8(dev2, pos2 + LINK_FREQ(offs2));
	old_freq &= 0x0f;
	needs_reset |= old_freq != freq;

	/* Set the Calulcated link frequency */
	pci_write_config8(dev1, pos1 + LINK_FREQ(offs1), freq);
	pci_write_config8(dev2, pos2 + LINK_FREQ(offs2), freq);

	/* Get the width capabilities */
	width_cap1 = pci_read_config8(dev1, pos1 + LINK_WIDTH(offs1));
	width_cap2 = pci_read_config8(dev2, pos2 + LINK_WIDTH(offs2));

	/* Calculate dev1's input width */
	ln_width1 = link_width_to_pow2[width_cap1 & 7];
	ln_width2 = link_width_to_pow2[(width_cap2 >> 4) & 7];
	if (ln_width1 > ln_width2) {
		ln_width1 = ln_width2;
	}
	width = pow2_to_link_width[ln_width1];
	/* Calculate dev1's output width */
	ln_width1 = link_width_to_pow2[(width_cap1 >> 4) & 7];
	ln_width2 = link_width_to_pow2[width_cap2 & 7];
	if (ln_width1 > ln_width2) {
		ln_width1 = ln_width2;
	}
	width |= pow2_to_link_width[ln_width1] << 4;

	/* See if I am changing dev1's width */
	old_width = pci_read_config8(dev1, pos1 + LINK_WIDTH(offs1) + 1);
	needs_reset |= old_width != width;

	/* Set dev1's widths */
	pci_write_config8(dev1, pos1 + LINK_WIDTH(offs1) + 1, width);

	/* Calculate dev2's width */
	width = ((width & 0x70) >> 4) | ((width & 0x7) << 4);

	/* See if I am changing dev2's width */
	old_width = pci_read_config8(dev2, pos2 + LINK_WIDTH(offs2) + 1);
	needs_reset |= old_width != width;

	/* Set dev2's widths */
	pci_write_config8(dev2, pos2 + LINK_WIDTH(offs2) + 1, width);

	return needs_reset;
}
#if (USE_DCACHE_RAM == 1) && (K8_SCAN_PCI_BUS == 1)
static int ht_setup_chainx(device_t udev, uint8_t upos, uint8_t bus);
static int scan_pci_bus( unsigned bus) 
{
        /*      
                here we already can access PCI_DEV(bus, 0, 0) to PCI_DEV(bus, 0x1f, 0x7)
                So We can scan these devices to find out if they are bridge 
                If it is pci bridge, We need to set busn in bridge, and go on
                For ht bridge, We need to set the busn in bridge and ht_setup_chainx, and the scan_pci_bus
        */    
	unsigned int devfn;
	unsigned new_bus;
	unsigned max_bus;

	new_bus = (bus & 0xff); // mask out the reset_needed

	if(new_bus<0x40) {
		max_bus = 0x3f;
	} else if (new_bus<0x80) {
		max_bus = 0x7f;
	} else if (new_bus<0xc0) {
		max_bus = 0xbf;
	} else {
		max_bus = 0xff;
	}

	new_bus = bus;

#if 0
#if CONFIG_USE_INIT == 1
	printk_debug("bus_num=%02x\r\n", bus);
#endif
#endif

	for (devfn = 0; devfn <= 0xff; devfn++) { 
	        uint8_t hdr_type;
	        uint16_t class;
		uint32_t buses;
		device_t dev;
		uint16_t cr;
		dev = PCI_DEV((bus & 0xff), ((devfn>>3) & 0x1f), (devfn & 0x7));
                hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
                class = pci_read_config16(dev, PCI_CLASS_DEVICE);

#if 0
#if CONFIG_USE_INIT == 1
		if(hdr_type !=0xff ) {
			printk_debug("dev=%02x fn=%02x hdr_type=%02x class=%04x\r\n", 
				(devfn>>3)& 0x1f, (devfn & 0x7), hdr_type, class);
		}
#endif
#endif
		switch(hdr_type & 0x7f) {  /* header type */
		        case PCI_HEADER_TYPE_BRIDGE:
		                if (class  != PCI_CLASS_BRIDGE_PCI) goto bad;
				/* set the bus range dev */

			        /* Clear all status bits and turn off memory, I/O and master enables. */
			        cr = pci_read_config16(dev, PCI_COMMAND);
			        pci_write_config16(dev, PCI_COMMAND, 0x0000);
			        pci_write_config16(dev, PCI_STATUS, 0xffff);

			        buses = pci_read_config32(dev, PCI_PRIMARY_BUS);

			        buses &= 0xff000000;
				new_bus++;
			        buses |= (((unsigned int) (bus & 0xff) << 0) |
			                ((unsigned int) (new_bus & 0xff) << 8) |
			                ((unsigned int) max_bus << 16));
			        pci_write_config32(dev, PCI_PRIMARY_BUS, buses);
				
				{
				/* here we need to figure out if dev is a ht bridge
					if it is ht bridge, we need to call ht_setup_chainx at first
				   Not verified --- yhlu
				*/
					uint8_t upos;
			                upos = ht_lookup_host_capability(dev); // one func one ht sub
			                if (upos) { // sub ht chain
						uint8_t busn;
						busn = (new_bus & 0xff);
				                /* Make certain the HT bus is not enumerated */
				                ht_collapse_previous_enumeration(busn);
						/* scan the ht chain */
				                new_bus |= (ht_setup_chainx(dev,upos,busn)<<16); // store reset_needed to upword
			                }
				}
				
				new_bus = scan_pci_bus(new_bus);
				/* set real max bus num in that */

			        buses = (buses & 0xff00ffff) |
			                ((unsigned int) (new_bus & 0xff) << 16);
				        pci_write_config32(dev, PCI_PRIMARY_BUS, buses);

				pci_write_config16(dev, PCI_COMMAND, cr);

                		break;  
        		default:
		        bad:
				;
        	}

                /* if this is not a multi function device, 
                 * or the device is not present don't waste
                 * time probing another function. 
                 * Skip to next device. 
                 */
                if ( ((devfn & 0x07) == 0x00) && ((hdr_type & 0x80) != 0x80))
                {
                        devfn += 0x07;
                }
        }
	
	return new_bus; 
}
#endif
static int ht_setup_chainx(device_t udev, uint8_t upos, uint8_t bus)
{
	uint8_t next_unitid, last_unitid;
	unsigned uoffs;
	int reset_needed=0;

	uoffs = PCI_HT_HOST_OFFS;
	next_unitid = 1;

	do {
		uint32_t id;
		uint8_t pos;
		uint16_t flags, ctrl;
		uint8_t count;
		unsigned offs;
	
		/* Wait until the link initialization is complete */
		do {
			ctrl = pci_read_config16(udev, upos + LINK_CTRL(uoffs));
			/* Is this the end of the hypertransport chain? */
			if (ctrl & (1 << 6)) {
				break;
			}
			/* Has the link failed */
			if (ctrl & (1 << 4)) {
				break;
			}
		} while((ctrl & (1 << 5)) == 0);
	
		device_t dev = PCI_DEV(bus, 0, 0);
		last_unitid = next_unitid;

		id = pci_read_config32(dev, PCI_VENDOR_ID);

		/* If the chain is enumerated quit */
		if (    (id == 0xffffffff) || (id == 0x00000000) ||
			(id == 0x0000ffff) || (id == 0xffff0000))
		{
			break;
		}

		pos = ht_lookup_slave_capability(dev);
		if (!pos) {
			print_err("HT link capability not found\r\n");
			break;
		}

#if CK804_DEVN_BASE==0 
                //CK804 workaround: 
                // CK804 UnitID changes not use
		id = pci_read_config32(dev, PCI_VENDOR_ID);
                if(id != 0x005e10de) {
#endif

		/* Update the Unitid of the current device */
		flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
		flags &= ~0x1f; /* mask out the bse Unit ID */
		flags |= next_unitid & 0x1f;
		pci_write_config16(dev, pos + PCI_CAP_FLAGS, flags);

		/* Note the change in device number */
		dev = PCI_DEV(bus, next_unitid, 0);
#if CK804_DEVN_BASE==0	
		} 
		else {
			dev = PCI_DEV(bus, 0, 0);
		}
#endif

                /* Compute the number of unitids consumed */
                count = (flags >> 5) & 0x1f;
                next_unitid += count;

		/* Find which side of the ht link we are on,
		 * by reading which direction our last write to PCI_CAP_FLAGS
		 * came from.
		 */
		flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
                offs = ((flags>>10) & 1) ? PCI_HT_SLAVE1_OFFS : PCI_HT_SLAVE0_OFFS;
                
                /* Setup the Hypertransport link */
                reset_needed |= ht_optimize_link(udev, upos, uoffs, dev, pos, offs);

#if CK804_DEVN_BASE==0
		if(id == 0x005e10de) {
			break;
		}
#endif

		/* Remeber the location of the last device */
		udev = dev;
		upos = pos;
		uoffs = ( offs != PCI_HT_SLAVE0_OFFS ) ? PCI_HT_SLAVE0_OFFS : PCI_HT_SLAVE1_OFFS;

	} while((last_unitid != next_unitid) && (next_unitid <= 0x1f));

	return reset_needed;
}

static int ht_setup_chain(device_t udev, unsigned upos)
{
        /* Assumption the HT chain that is bus 0 has the HT I/O Hub on it.
         * On most boards this just happens.  If a cpu has multiple
         * non Coherent links the appropriate bus registers for the
         * links needs to be programed to point at bus 0.
         */

        /* Make certain the HT bus is not enumerated */
        ht_collapse_previous_enumeration(0);

        return ht_setup_chainx(udev, upos, 0);
}
static int optimize_link_read_pointer(uint8_t node, uint8_t linkn, uint8_t linkt, uint8_t val)
{
	uint32_t dword, dword_old;
	uint8_t link_type;
	
	/* This works on an Athlon64 because unimplemented links return 0 */
	dword = pci_read_config32(PCI_DEV(0,0x18+node,0), 0x98 + (linkn * 0x20));
	link_type = dword & 0xff;
	
	dword_old = dword = pci_read_config32(PCI_DEV(0,0x18+node,3), 0xdc);
	
	if ( (link_type & 7) == linkt ) { /* Coherent Link only linkt = 3, ncoherent = 7*/
		dword &= ~( 0xff<<(linkn *8) );
		dword |= val << (linkn *8);
	}
	
	if (dword != dword_old) {
		pci_write_config32(PCI_DEV(0,0x18+node,3), 0xdc, dword);
		return 1;
	}
	
	return 0;
}

static int optimize_link_in_coherent(uint8_t ht_c_num)
{
	int reset_needed; 
	uint8_t i;

	reset_needed = 0;

	for (i = 0; i < ht_c_num; i++) {
		uint32_t reg;
		uint8_t nodeid, linkn;
		uint8_t busn;
		uint8_t val;

		reg = pci_read_config32(PCI_DEV(0,0x18,1), 0xe0 + i * 4);
		
		nodeid = ((reg & 0xf0)>>4); // nodeid
		linkn = ((reg & 0xf00)>>8); // link n
		busn = (reg & 0xff0000)>>16; //busn
	
		reg = pci_read_config32( PCI_DEV(busn, 1, 0), PCI_VENDOR_ID);
		if ( (reg & 0xffff) == PCI_VENDOR_ID_AMD) {
			val = 0x25;
		} else if ( (reg & 0xffff) == PCI_VENDOR_ID_NVIDIA ) {
			val = 0x25;//???
		} else {
			continue;
		}

		reset_needed |= optimize_link_read_pointer(nodeid, linkn, 0x07, val);

	}

	return reset_needed;
}

static int ht_setup_chains(uint8_t ht_c_num)
{
	/* Assumption the HT chain that is bus 0 has the HT I/O Hub on it. 
	 * On most boards this just happens.  If a cpu has multiple
	 * non Coherent links the appropriate bus registers for the
	 * links needs to be programed to point at bus 0.
	 */
	int reset_needed; 
        uint8_t upos;
        device_t udev;
	uint8_t i;

	reset_needed = 0;

	for (i = 0; i < ht_c_num; i++) {
		uint32_t reg;
		uint8_t devpos;
		unsigned regpos;
		uint32_t dword;
		uint8_t busn;
		#if (USE_DCACHE_RAM == 1) && (K8_SCAN_PCI_BUS == 1)
		unsigned bus;
		#endif
		
		reg = pci_read_config32(PCI_DEV(0,0x18,1), 0xe0 + i * 4);

		//We need setup 0x94, 0xb4, and 0xd4 according to the reg
		devpos = ((reg & 0xf0)>>4)+0x18; // nodeid; it will decide 0x18 or 0x19
		regpos = ((reg & 0xf00)>>8) * 0x20 + 0x94; // link n; it will decide 0x94 or 0xb4, 0x0xd4;
		busn = (reg & 0xff0000)>>16;
		
		dword = pci_read_config32( PCI_DEV(0, devpos, 0), regpos) ;
		dword &= ~(0xffff<<8);
		dword |= (reg & 0xffff0000)>>8;
		pci_write_config32( PCI_DEV(0, devpos,0), regpos , dword);
		
	        /* Make certain the HT bus is not enumerated */
        	ht_collapse_previous_enumeration(busn);

		upos = ((reg & 0xf00)>>8) * 0x20 + 0x80;
		udev =  PCI_DEV(0, devpos, 0);
		
		reset_needed |= ht_setup_chainx(udev,upos,busn);

		#if (USE_DCACHE_RAM == 1) && (K8_SCAN_PCI_BUS == 1)
	        /* You can use use this in romcc, because there is function call in romcc, recursive will kill you */
		bus = busn; // we need 32 bit 
        	reset_needed |= (scan_pci_bus(bus)>>16); // take out reset_needed that stored in upword
		#endif
	}

	reset_needed |= optimize_link_in_coherent(ht_c_num);		
	
	return reset_needed;
}

#ifndef K8_ALLOCATE_IO_RANGE 
	#define K8_ALLOCATE_IO_RANGE 0
#endif

static int ht_setup_chains_x(void)
{               
        uint8_t nodeid;
        uint32_t reg; 
	uint32_t tempreg;
        uint8_t next_busn;
        uint8_t ht_c_num;
	uint8_t nodes;
#if K8_ALLOCATE_IO_RANGE == 1	
	unsigned next_io_base;
#endif
      
        /* read PCI_DEV(0,0x18,0) 0x64 bit [8:9] to find out SbLink m */
        reg = pci_read_config32(PCI_DEV(0, 0x18, 0), 0x64);
        /* update PCI_DEV(0, 0x18, 1) 0xe0 to 0x05000m03, and next_busn=0x3f+1 */
	print_linkn_in("SBLink=", ((reg>>8) & 3) );
        tempreg = 3 | ( 0<<4) | (((reg>>8) & 3)<<8) | (0<<16)| (0x3f<<24);
        pci_write_config32(PCI_DEV(0, 0x18, 1), 0xe0, tempreg);

	next_busn=0x3f+1; /* 0 will be used ht chain with SB we need to keep SB in bus0 in auto stage*/

#if K8_ALLOCATE_IO_RANGE == 1
	/* io range allocation */
	tempreg = 0 | (((reg>>8) & 0x3) << 4 )|  (0x3<<12); //limit
	pci_write_config32(PCI_DEV(0, 0x18, 1), 0xC4, tempreg);
	tempreg = 3 | ( 3<<4) | (0<<12);	//base
	pci_write_config32(PCI_DEV(0, 0x18, 1), 0xC0, tempreg);
	next_io_base = 0x3+0x1;
#endif

	/* clean others */
        for(ht_c_num=1;ht_c_num<4; ht_c_num++) {
                pci_write_config32(PCI_DEV(0, 0x18, 1), 0xe0 + ht_c_num * 4, 0);
		/* io range allocation */
		pci_write_config32(PCI_DEV(0, 0x18, 1), 0xc4 + ht_c_num * 8, 0);
		pci_write_config32(PCI_DEV(0, 0x18, 1), 0xc0 + ht_c_num * 8, 0);
        }
 
	nodes = ((pci_read_config32(PCI_DEV(0, 0x18, 0), 0x60)>>4) & 7) + 1;

        for(nodeid=0; nodeid<nodes; nodeid++) {
                device_t dev; 
                uint8_t linkn;
                dev = PCI_DEV(0, 0x18+nodeid,0);
                for(linkn = 0; linkn<3; linkn++) {
                        unsigned regpos;
                        regpos = 0x98 + 0x20 * linkn;
                        reg = pci_read_config32(dev, regpos);
                        if ((reg & 0x17) != 7) continue; /* it is not non conherent or not connected*/
			print_linkn_in("NC node|link=", ((nodeid & 0xf)<<4)|(linkn & 0xf));
                        tempreg = 3 | (nodeid <<4) | (linkn<<8);
                        /*compare (temp & 0xffff), with (PCI(0, 0x18, 1) 0xe0 to 0xec & 0xfffff) */
                        for(ht_c_num=0;ht_c_num<4; ht_c_num++) {
                                reg = pci_read_config32(PCI_DEV(0, 0x18, 1), 0xe0 + ht_c_num * 4);
                                if(((reg & 0xffff) == (tempreg & 0xffff)) || ((reg & 0xffff) == 0x0000)) {  /*we got it*/
                                        break;
                                }
                        }
                        if(ht_c_num == 4) break; /*used up only 4 non conherent allowed*/
                        /*update to 0xe0...*/
			if((reg & 0xf) == 3) continue; /*SbLink so don't touch it */
			print_linkn_in("\tbusn=", next_busn);
                        tempreg |= (next_busn<<16)|((next_busn+0x3f)<<24);
                        pci_write_config32(PCI_DEV(0, 0x18, 1), 0xe0 + ht_c_num * 4, tempreg);
			next_busn+=0x3f+1;

#if K8_ALLOCATE_IO_RANGE == 1			
			/* io range allocation */
		        tempreg = nodeid | (linkn<<4) |  ((next_io_base+0x3)<<12); //limit
		        pci_write_config32(PCI_DEV(0, 0x18, 1), 0xC4 + ht_c_num * 8, tempreg);
		        tempreg = 3 | ( 3<<4) | (next_io_base<<12);        //base
		        pci_write_config32(PCI_DEV(0, 0x18, 1), 0xC0 + ht_c_num * 8, tempreg);
		        next_io_base += 0x3+0x1;
#endif

                }
        }
        /*update 0xe0, 0xe4, 0xe8, 0xec from PCI_DEV(0, 0x18,1) to PCI_DEV(0, 0x19,1) to PCI_DEV(0, 0x1f,1);*/

        for(nodeid = 1; nodeid<nodes; nodeid++) {
                int i;
                device_t dev;
                dev = PCI_DEV(0, 0x18+nodeid,1);
                for(i = 0; i< 4; i++) {
                        unsigned regpos;
                        regpos = 0xe0 + i * 4;
                        reg = pci_read_config32(PCI_DEV(0, 0x18, 1), regpos);
                        pci_write_config32(dev, regpos, reg);
                }

#if K8_ALLOCATE_IO_RANGE == 1
		/* io range allocation */
                for(i = 0; i< 4; i++) {
                        unsigned regpos;
                        regpos = 0xc4 + i * 8;
                        reg = pci_read_config32(PCI_DEV(0, 0x18, 1), regpos);
                        pci_write_config32(dev, regpos, reg);
                }
                for(i = 0; i< 4; i++) {
                        unsigned regpos;
                        regpos = 0xc0 + i * 8;
                        reg = pci_read_config32(PCI_DEV(0, 0x18, 1), regpos);
                        pci_write_config32(dev, regpos, reg);
                }
#endif
        }
	
	/* recount ht_c_num*/
	uint8_t i=0;
        for(ht_c_num=0;ht_c_num<4; ht_c_num++) {
		reg = pci_read_config32(PCI_DEV(0, 0x18, 1), 0xe0 + ht_c_num * 4);
                if(((reg & 0xf) != 0x0)) {
			i++;
		}
        }

        return ht_setup_chains(i);

}