clear dead link bug fix and opt_link_read for non coherent link

[coreboot.git] / src / northbridge / amd / amdk8 / coherent_ht.c

/* coherent hypertransport initialization for AMD64 
 * 
 * written by Stefan Reinauer <stepan@openbios.org>
 * (c) 2003-2004 by SuSE Linux AG
 *
 * (c) 2004 Tyan Computer
 *  2004.12 yhlu added support to create routing table dynamically.
 *          it also support 8 ways too. (8 ways ladder or 8 ways crossbar)
 *
 * This code is licensed under GPL.
 */

/*
 * This algorithm assumes a grid configuration as follows:
 *
 * nodes :  1    2    4    6    8
 * org.  :  1x1  2x1  2x2  2x3  2x4
 Ladder:
                        CPU7-------------CPU6 
                        |                |    
                        |                |
                        |                | 
                        |                |     
                        |                |        
                        |                |    
                        CPU5-------------CPU4                    
                        |                |    
                        |                |   
                        |                |  
                        |                |    
                        |                |         
                        |                |       
                        CPU3-------------CPU2              
                        |                |    
                        |                | 
                        |                |
                        |                |
                        |                | 
                        |                |    
                        CPU1-------------CPU0    
 CROSS_BAR_47_56:
                        CPU7-------------CPU6 
                        |  \____    ___/ |    
                        |       \  /     |
                        |        \/      | 
                        |        /\      |     
                        |       /  \     |        
                        |  ____/    \___ |    
                        CPU5             CPU4                    
                        |                |    
                        |                |   
                        |                |  
                        |                |    
                        |                |         
                        |                |       
                        CPU3-------------CPU2              
                        |                |    
                        |                | 
                        |                |
                        |                |
                        |                | 
                        |                |    
                        CPU1-------------CPU0           
 */

#include <device/pci_def.h>
#include <device/pci_ids.h>
#include <device/hypertransport_def.h>
#include "arch/romcc_io.h"
#include "amdk8.h"

#define enable_bsp_routing()    enable_routing(0)

#define NODE_HT(x) PCI_DEV(0,24+x,0)
#define NODE_MP(x) PCI_DEV(0,24+x,1)
#define NODE_MC(x) PCI_DEV(0,24+x,3)

#define DEFAULT 0x00010101      /* default row entry */

typedef uint8_t u8;
typedef uint32_t u32;

#ifndef CROSS_BAR_47_56
        #define CROSS_BAR_47_56 0
#endif

#ifndef TRY_HIGH_FIRST
        #define TRY_HIGH_FIRST 0
#endif


static inline void print_linkn (const char *strval, uint8_t byteval) 
{
#if 1
        print_debug(strval); print_debug_hex8(byteval); print_debug("\r\n");
#endif
}

static void disable_probes(void)
{
        /* disable read/write/fill probes for uniprocessor setup
         * they don't make sense if only one cpu is available
         */

        /* Hypetransport Transaction Control Register 
         * F0:0x68
         * [ 0: 0] Disable read byte probe
         *         0 = Probes issues
         *         1 = Probes not issued
         * [ 1: 1] Disable Read Doubleword probe
         *         0 = Probes issued
         *         1 = Probes not issued
         * [ 2: 2] Disable write byte probes
         *         0 = Probes issued
         *         1 = Probes not issued
         * [ 3: 3] Disable Write Doubleword Probes
         *         0 = Probes issued
         *         1 = Probes not issued.
         * [10:10] Disable Fill Probe
         *         0 = Probes issued for cache fills
         *         1 = Probes not issued for cache fills.
         */

        u32 val;

        print_spew("Disabling read/write/fill probes for UP... ");

        val=pci_read_config32(NODE_HT(0), 0x68);
        val |= (1<<10)|(1<<9)|(1<<8)|(1<<4)|(1<<3)|(1<<2)|(1<<1)|(1 << 0);
        pci_write_config32(NODE_HT(0), 0x68, val);

        print_spew("done.\r\n");

}

#ifndef ENABLE_APIC_EXT_ID
#define ENABLE_APIC_EXT_ID 0 
#endif

static void enable_apic_ext_id(u8 node)
{
#if ENABLE_APIC_EXT_ID==1
#warning "FIXME Is the right place to enable apic ext id here?"

        u32 val;

        val = pci_read_config32(NODE_HT(node), 0x68);
        val |= HTTC_APIC_EXT_ID | HTTC_APIC_EXT_BRD_CST ;
        pci_write_config32(NODE_HT(node), 0x68, val);
#endif
}

static void enable_routing(u8 node)
{
        u32 val;

        /* HT Initialization Control Register
         * F0:0x6C
         * [ 0: 0] Routing Table Disable
         *         0 = Packets are routed according to routing tables
         *         1 = Packets are routed according to the default link field
         * [ 1: 1] Request Disable (BSP should clear this)
         *         0 = Request packets may be generated
         *         1 = Request packets may not be generated.
         * [ 3: 2] Default Link (Read-only)
         *         00 = LDT0
         *         01 = LDT1
         *         10 = LDT2
         *         11 = CPU on same node
         * [ 4: 4] Cold Reset
         *         - Scratch bit cleared by a cold reset
         * [ 5: 5] BIOS Reset Detect
         *         - Scratch bit cleared by a cold reset
         * [ 6: 6] INIT Detect
         *         - Scratch bit cleared by a warm or cold reset not by an INIT
         *
         */

        /* Enable routing table */
        print_spew("Enabling routing table for node ");
        print_spew_hex8(node);
        
        val=pci_read_config32(NODE_HT(node), 0x6c);
        val &= ~((1<<1)|(1<<0));
        pci_write_config32(NODE_HT(node), 0x6c, val);

        print_spew(" done.\r\n");
}

static void fill_row(u8 node, u8 row, u32 value)
{
        pci_write_config32(NODE_HT(node), 0x40+(row<<2), value);
}

#if CONFIG_MAX_CPUS > 1
static u8 link_to_register(int ldt)
{
        /*
         * [ 0: 3] Request Route
         *     [0] Route to this node
         *     [1] Route to Link 0
         *     [2] Route to Link 1
         *     [3] Route to Link 2
         */

        if (ldt&0x08) return 0x40;
        if (ldt&0x04) return 0x20;
        if (ldt&0x02) return 0x00;
        
        /* we should never get here */
        print_spew("Unknown Link\n");
        return 0;
}

static u32 get_row(u8 node, u8 row)
{
        return pci_read_config32(NODE_HT(node), 0x40+(row<<2));
}

static int link_connection(u8 src, u8 dest)
{
        return get_row(src, dest) & 0x0f;
}

static void rename_temp_node(u8 node)
{
        uint32_t val;

        print_spew("Renaming current temporary node to ");
        print_spew_hex8(node);

        val=pci_read_config32(NODE_HT(7), 0x60);
        val &= (~7);  /* clear low bits. */
        val |= node;   /* new node        */
        pci_write_config32(NODE_HT(7), 0x60, val);

        print_spew(" done.\r\n");
}

static int check_connection(u8 dest)
{
        /* See if we have a valid connection to dest */
        u32 val;

        /* Verify that the coherent hypertransport link is
         * established and actually working by reading the
         * remode node's vendor/device id
         */
        val = pci_read_config32(NODE_HT(dest),0);
        if(val != 0x11001022)
                return 0;

        return 1;
}

static unsigned read_freq_cap(device_t dev, unsigned pos)
{
        /* Handle bugs in valid hypertransport frequency reporting */
        unsigned 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))) {
                freq_cap &= ~(1 << HT_FREQ_1000Mhz);
        }
        return freq_cap;
}

static int optimize_connection(device_t node1, uint8_t link1, device_t node2, uint8_t link2)
{
        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, freq_cap, freq_mask;
        uint8_t width_cap1, width_cap2, width_cap, 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 = read_freq_cap(node1, link1 + PCI_HT_CAP_HOST_FREQ_CAP);
        freq_cap2 = read_freq_cap(node2, link2 + PCI_HT_CAP_HOST_FREQ_CAP);

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

        /* See if I am changing the link freqency */
        old_freq = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_FREQ);
        needs_reset |= old_freq != freq;
        old_freq = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_FREQ);
        needs_reset |= old_freq != freq;

        /* Set the Calulcated link frequency */
        pci_write_config8(node1, link1 + PCI_HT_CAP_HOST_FREQ, freq);
        pci_write_config8(node2, link2 + PCI_HT_CAP_HOST_FREQ, freq);

        /* Get the width capabilities */
        width_cap1 = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH);
        width_cap2 = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH);

        /* Calculate node1'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 node1'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 node1's width */
        old_width = pci_read_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH + 1);
        needs_reset |= old_width != width;

        /* Set node1's widths */
        pci_write_config8(node1, link1 + PCI_HT_CAP_HOST_WIDTH + 1, width);

        /* Calculate node2's width */
        width = ((width & 0x70) >> 4) | ((width & 0x7) << 4);

        /* See if I am changing node2's width */
        old_width = pci_read_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH + 1);
        needs_reset |= old_width != width;

        /* Set node2's widths */
        pci_write_config8(node2, link2 + PCI_HT_CAP_HOST_WIDTH + 1, width);

        return needs_reset;
}

static void setup_row_local(u8 source, u8 row) /* source will be 7 when it is for temp use*/
{
        unsigned linkn;
        uint32_t val;
        val = 1;
        for(linkn = 0; linkn<3; linkn++) { 
                unsigned regpos; 
                uint32_t reg;
                regpos = 0x98 + 0x20 * linkn;
                reg = pci_read_config32(NODE_HT(source), regpos);
                if ((reg & 0x17) != 3) continue; /* it is not conherent or not connected*/
                val |= 1<<(linkn+1); 
        }
        val <<= 16;
        val |= 0x0101;
        fill_row(source,row, val);
}

static void setup_row_direct_x(u8 temp, u8 source, u8 dest, u8 linkn)
{
        uint32_t val;
        uint32_t val_s;
        val = 1<<(linkn+1);
        val |= 1<<(linkn+1+8); /*for direct connect response route should equal to request table*/

        if(((source &1)!=(dest &1)) 
#if CROSS_BAR_47_56
                && (source<4) && (dest<4) 
#endif
        ){
                val |= (1<<16);
        } else {
                /*for CROSS_BAR_47_56  47, 74, 56, 65 should be here too*/
                val_s = get_row(temp, source);
                val |= ((val_s>>16) - (1<<(linkn+1)))<<16;
        }

        fill_row(temp,dest, val );
}

static void setup_row_direct(u8 source, u8 dest, u8 linkn){
        setup_row_direct_x(source, source, dest, linkn);
}

static void setup_remote_row_direct(u8 source, u8 dest, u8 linkn){
        setup_row_direct_x(7, source, dest, linkn);
}

static uint8_t get_linkn_first(uint8_t byte)
{
        if(byte & 0x02) { byte = 0; }
        else if(byte & 0x04) { byte = 1; }
        else if(byte & 0x08) { byte = 2; }
        return byte; 
}

static uint8_t get_linkn_last(uint8_t byte)
{
        if(byte & 0x02) { byte &= 0x0f; byte |= 0x00;  }
        if(byte & 0x04) { byte &= 0x0f; byte |= 0x10;  }
        if(byte & 0x08) { byte &= 0x0f; byte |= 0x20;  }
        return byte>>4; 
}

static uint8_t get_linkn_last_count(uint8_t byte)
{
        byte &= 0x3f;
        if(byte & 0x02) { byte &= 0xcf; byte |= 0x00; byte+=0x40; }
        if(byte & 0x04) { byte &= 0xcf; byte |= 0x10; byte+=0x40; }
        if(byte & 0x08) { byte &= 0xcf; byte |= 0x20; byte+=0x40; }
        return byte>>4;
}

static void setup_temp_row(u8 source, u8 dest)
{
        /* copy val from (source, dest) to (source,7) */
        fill_row(source,7,get_row(source,dest));
}

static void clear_temp_row(u8 source)
{
        fill_row(source, 7, DEFAULT);
}

static void setup_remote_node(u8 node)
{
        static const uint8_t pci_reg[] = { 
                0x44, 0x4c, 0x54, 0x5c, 0x64, 0x6c, 0x74, 0x7c, 
                0x40, 0x48, 0x50, 0x58, 0x60, 0x68, 0x70, 0x78,
                0x84, 0x8c, 0x94, 0x9c, 0xa4, 0xac, 0xb4, 0xbc,
                0x80, 0x88, 0x90, 0x98, 0xa0, 0xa8, 0xb0, 0xb8,
                0xc4, 0xcc, 0xd4, 0xdc,
                0xc0, 0xc8, 0xd0, 0xd8,
                0xe0, 0xe4, 0xe8, 0xec,
        };
        int i;

        print_spew("setup_remote_node: ");

        /* copy the default resource map from node 0 */
        for(i = 0; i < sizeof(pci_reg)/sizeof(pci_reg[0]); i++) {
                uint32_t value;
                uint8_t reg;
                reg = pci_reg[i];
                value = pci_read_config32(NODE_MP(0), reg);
                pci_write_config32(NODE_MP(7), reg, value);

        }
        print_spew("done\r\n");
}

#endif /* CONFIG_MAX_CPUS > 1*/


#if CONFIG_MAX_CPUS > 2
#if !CROSS_BAR_47_56
static void setup_row_indirect_x(u8 temp, u8 source, u8 dest, u8 gateway)
#else
static void setup_row_indirect_x(u8 temp, u8 source, u8 dest, u8 gateway, u8 diff)
#endif
{
        /*for indirect connection, we need to compute the val from val_s(source, source), and val_g(source, gateway) */
        uint32_t val_s;
        uint32_t val;
#if !CROSS_BAR_47_56    
        u8 diff;
#endif
        val_s = get_row(temp, source);
        val = get_row(temp, gateway);
        
        val &= 0xffff;
        val_s >>= 16;
        val_s &= 0xfe;
        
#if !CROSS_BAR_47_56
        diff = ((source&1)!=(dest &1));
#endif

        if(diff && (val_s!=(val&0xff)) ) { /* use another connect as response*/
                val_s -= val &  0xff;
#if CONFIG_MAX_CPUS > 4
                uint8_t byte;
                /* Some node have two links left
                 * don't worry we only have (2, (3 as source need to handle
                 */
                byte = val_s;
                byte = get_linkn_last_count(byte);
                if((byte>>2)>1) { /* make sure not the corner*/
                        if(source<dest) {
                                val_s-=link_connection(temp, source-2); /* -down*/
                        } else {
                                val_s-=link_connection(temp, source+2); /* -up*/
                        }
                }
#endif
                val &= 0xff;
                val |= (val_s<<8);
        } 

        if(diff) { /* cross rung?*/
                val |= (1<<16);
        }
        else {
                val_s = get_row(temp, source);
                val |= ((val_s>>16) - link_connection(temp, gateway))<<16; 
        }

        fill_row(temp, dest, val);

}

#if !CROSS_BAR_47_56
static void setup_row_indirect(u8 source, u8 dest, u8 gateway)
{       
        setup_row_indirect_x(source, source, dest, gateway);
}
#else           
static void setup_row_indirect(u8 source, u8 dest, u8 gateway, u8 diff)
{
        setup_row_indirect_x(source, source, dest, gateway, diff);
}
#endif   

static void setup_row_indirect_group(const u8 *conn, int num)
{
        int i;

#if !CROSS_BAR_47_56
        for(i=0; i<num; i+=3) {
                setup_row_indirect(conn[i], conn[i+1],conn[i+2]);
#else
        for(i=0; i<num; i+=4) {
                setup_row_indirect(conn[i], conn[i+1],conn[i+2], conn[i+3]);
#endif

        }
}

#if !CROSS_BAR_47_56
static void setup_remote_row_indirect(u8 source, u8 dest, u8 gateway)
{
        setup_row_indirect_x(7, source, dest, gateway);
}
#else
static void setup_remote_row_indirect(u8 source, u8 dest, u8 gateway, u8 diff)
{
        setup_row_indirect_x(7, source, dest, gateway, diff);
}
#endif

static void setup_remote_row_indirect_group(const u8 *conn, int num)
{
        int i;

#if !CROSS_BAR_47_56
        for(i=0; i<num; i+=3) {
                setup_remote_row_indirect(conn[i], conn[i+1],conn[i+2]);
#else
        for(i=0; i<num; i+=4) {
                setup_remote_row_indirect(conn[i], conn[i+1],conn[i+2], conn[i+3]);
#endif
        }
}

#endif /*CONFIG_MAX_CPUS > 2*/


static void setup_uniprocessor(void)
{
        print_spew("Enabling UP settings\r\n");
        disable_probes();
}

struct setup_smp_result {
        int nodes;
        int needs_reset;
};

#if CONFIG_MAX_CPUS > 2
static int optimize_connection_group(const u8 *opt_conn, int num) {
        int needs_reset = 0;
        int i;
        for(i=0; i<num; i+=2) {
                needs_reset = optimize_connection(
                        NODE_HT(opt_conn[i]), 0x80 + link_to_register(link_connection(opt_conn[i],opt_conn[i+1])),
                        NODE_HT(opt_conn[i+1]), 0x80 + link_to_register(link_connection(opt_conn[i+1],opt_conn[i])) );
        }               
        return needs_reset;
}  
#endif

#if CONFIG_MAX_CPUS > 1
static struct setup_smp_result setup_smp2(void)
{
        struct setup_smp_result result;
        u8 byte;
        uint32_t val;
        result.nodes = 2;
        result.needs_reset = 0;

        setup_row_local(0, 0); /* it will update the broadcast RT*/
        
        val = get_row(0,0);
        byte = (val>>16) & 0xfe;
        if(byte<0x2) { /* no coherent connection so get out.*/
                result.nodes = 1;
                return result;
        }

        /* Setup and check a temporary connection to node 1 */
#if TRY_HIGH_FIRST == 1
        byte = get_linkn_last(byte); /* Max Link to node1 */
#else
        byte = get_linkn_first(byte); /*Min Link to node1 --- according to AMD*/
#endif
        print_linkn("(0,1) link=", byte);
        setup_row_direct(0,1, byte);
        setup_temp_row(0, 1);
        
        if (!check_connection(7)) {
                print_spew("No connection to Node 1.\r\n");
                result.nodes = 1;
                return result;
        }

        /* We found 2 nodes so far */
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /*get default link on node7 to node0*/
        print_linkn("(1,0) link=", byte);
        setup_row_local(7,1);
        setup_remote_row_direct(1, 0, byte);

#if CONFIG_MAX_CPUS > 4    
        val = get_row(7,1);
        byte = (val>>16) & 0xfe;
        byte = get_linkn_last_count(byte);
        if((byte>>2)==3) { /* Oh! we need to treat it as node2. So use another link*/
                val = get_row(0,0);
                byte = (val>>16) & 0xfe;
#if TRY_HIGH_FIRST == 1
                byte = get_linkn_first(byte); /* Min link to Node1 */
#else
                byte = get_linkn_last(byte);  /* Max link to Node1*/
#endif
                print_linkn("-->(0,1) link=", byte);
                setup_row_direct(0,1, byte);
                setup_temp_row(0, 1);
        
                if (!check_connection(7)) {
                        print_spew("No connection to Node 1.\r\n");
                        result.nodes = 1;
                        return result;
                }               
                        
                /* We found 2 nodes so far */
                val = pci_read_config32(NODE_HT(7), 0x6c);
                byte = (val>>2) & 0x3; /* get default link on node7 to node0*/
                print_linkn("-->(1,0) link=", byte); 
                setup_row_local(7,1);
                setup_remote_row_direct(1, 0, byte);
        }
#endif
        
        setup_remote_node(1);  /* Setup the regs on the remote node */
        rename_temp_node(1);    /* Rename Node 7 to Node 1  */
        enable_routing(1);      /* Enable routing on Node 1 */
#if 0
        /*don't need and it is done by clear_dead_links */
        clear_temp_row(0);
#endif
        
        result.needs_reset = optimize_connection(
                NODE_HT(0), 0x80 + link_to_register(link_connection(0,1)),
                NODE_HT(1), 0x80 + link_to_register(link_connection(1,0)) );


        return result;
}
#endif /*CONFIG_MAX_CPUS > 1 */

#if CONFIG_MAX_CPUS > 2

static struct setup_smp_result setup_smp4(int needs_reset)
{
        struct setup_smp_result result;
        u8 byte;
        uint32_t val;

        result.nodes=4;
        result.needs_reset = needs_reset;

        /* Setup and check temporary connection from Node 0 to Node 2 */
        val = get_row(0,0);
        byte = ((val>>16) & 0xfe) - link_connection(0,1);
        byte = get_linkn_last_count(byte);

        if((byte>>2)==0) { /* We should have two coherent for 4p and above*/
                result.nodes = 2;
                return result;
        }

        byte &= 3; /* bit [3,2] is count-1*/
        print_linkn("(0,2) link=", byte); 
        setup_row_direct(0, 2, byte);  /*(0,2) direct link done*/
        setup_temp_row(0, 2);

        if (!check_connection(7) ) {
                print_spew("No connection to Node 2.\r\n");
                result.nodes = 2;
                return result;
        }

        /* We found 3 nodes so far. Now setup a temporary
        * connection from node 0 to node 3 via node 1
        */
        setup_temp_row(0,1); /* temp. link between nodes 0 and 1 */
        /* here should setup_row_direct(1,3) at first, before that we should find the link in node 1 to 3*/
        val = get_row(1,1);
        byte = ((val>>16) & 0xfe) - link_connection(1,0);
        byte = get_linkn_first(byte);
        print_linkn("(1,3) link=", byte); 
        setup_row_direct(1,3,byte);  /* (1, 3) direct link done*/
        setup_temp_row(1,3); /* temp. link between nodes 1 and 3 */
        
        if (!check_connection(7)) {
                print_spew("No connection to Node 3.\r\n");
                result.nodes = 2;
                return result;
        }

        /* We found 4 nodes so far. Now setup all nodes for 4p */
#if !CROSS_BAR_47_56
        static const u8 conn4_1[] = {
                0,3,2,
                1,2,3,
        };      
#else
        static const u8 conn4_1[] = {
                0,3,2,1,
                1,2,3,1,
        };
#endif

        setup_row_indirect_group(conn4_1, sizeof(conn4_1)/sizeof(conn4_1[0]));

        setup_temp_row(0,2);

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 0*/
        print_linkn("(2,0) link=", byte); 

        setup_row_local(7,2);
        setup_remote_row_direct(2, 0, byte);
        setup_remote_node(2);  /* Setup the regs on the remote node */
#if !CROSS_BAR_47_56
        static const u8 conn4_2[] = {
                2,1,0,
        };
#else   
        static const u8 conn4_2[] = {
                2,1,0,1, 
        };      
#endif          
        setup_remote_row_indirect_group(conn4_2, sizeof(conn4_2)/sizeof(conn4_2[0]));

        rename_temp_node(2);    /* Rename Node 7 to Node 2  */
        enable_routing(2);      /* Enable routing on Node 2 */

        setup_temp_row(0,1);
        setup_temp_row(1,3);

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 1*/
        print_linkn("(3,1) link=", byte); 

        setup_row_local(7,3);
        setup_remote_row_direct(3, 1, byte);
        setup_remote_node(3);  /* Setup the regs on the remote node */

#if !CROSS_BAR_47_56
        static const u8 conn4_3[] = {
                3,0,1,
        };
#else   
        static const u8 conn4_3[] = {
                3,0,1,1,
        };      
#endif          
        setup_remote_row_indirect_group(conn4_3, sizeof(conn4_3)/sizeof(conn4_3[0]));

        /* We need to init link between 2, and 3 direct link */
        val = get_row(2,2);
        byte = ((val>>16) & 0xfe) - link_connection(2,0);
        byte = get_linkn_last_count(byte);
        print_linkn("(2,3) link=", byte & 3);
        
        setup_row_direct(2,3, byte & 0x3);
        setup_temp_row(0,2);
        setup_temp_row(2,3);
        check_connection(7); /* to 3*/

#if CONFIG_MAX_CPUS > 4
        /* We need to find out which link is to node3 */
        
        if((byte>>2)==2) { /* one to node3, one to node0, one to node4*/
                val = get_row(7,3);
                if((val>>16) == 1) { /* that link is to node4, because via node3 it has been set, recompute it*/
                        val = get_row(2,2);
                        byte = ((val>>16) & 0xfe) - link_connection(2,0);
                        byte = get_linkn_first(byte);
                        print_linkn("-->(2,3) link=", byte); 
                        setup_row_direct(2,3,byte);
                        setup_temp_row(2,3);
                        check_connection(7); /* to 3*/
                }
        } 
#endif

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 2*/
        print_linkn("(3,2) link=", byte); 
        setup_remote_row_direct(3,2, byte);

/* ready to enable RT for Node 3 */
        rename_temp_node(3);
        enable_routing(3);      /* enable routing on node 3 (temp.) */

#if 0
        /*We need to do sth to reverse work for setup_temp_row (0,1) (1,3) */
        /* it will be done by clear_dead_links */
        clear_temp_row(0);
        clear_temp_row(1);
#endif

        /* optimize physical connections - by LYH */
        static const u8 opt_conn4[] = {
                0,2,
                1,3,
                2,3,
        };

        result.needs_reset = optimize_connection_group(opt_conn4, sizeof(opt_conn4)/sizeof(opt_conn4[0]));
        
        return result;

}

#endif /* CONFIG_MAX_CPUS > 2 */

#if CONFIG_MAX_CPUS > 4

static struct setup_smp_result setup_smp6(int needs_reset)
{
        struct setup_smp_result result;
        u8 byte;
        uint32_t val;

        result.nodes=6;
        result.needs_reset = needs_reset;

        /* Setup and check temporary connection from Node 0 to Node 4 via 2 */
        val = get_row(2,2);
        byte = ((val>>16) & 0xfe) - link_connection(2,3) - link_connection(2,0);
        byte = get_linkn_last_count(byte);

        if((byte>>2)==0) { /* We should have two coherent link on node 2 for 6p and above*/
                result.nodes = 4;
                return result;
        }
        byte &= 3; /* bit [3,2] is count-2*/
        print_linkn("(2,4) link=", byte);
        setup_row_direct(2, 4, byte);
        
        /* Setup and check temporary connection from Node 0 to Node 4  through 2*/
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte,byte+2); 
        }

        if (!check_connection(7) ) {
                print_spew("No connection to Node 4.\r\n");
                result.nodes = 4;
                return result; 
        }       

        /* Setup and check temporary connection from Node 0 to Node 5  through 1, 3*/
        val = get_row(3,3);
        byte = ((val>>16) & 0xfe) - link_connection(3,2) - link_connection(3,1);
        byte = get_linkn_last_count(byte);
        if((byte>>2)==0) { /* We should have two coherent links on node 3 for 6p and above*/
                result.nodes = 4;
                return result;
        }

        byte &= 3; /*bit [3,2] is count-2*/
        print_linkn("(3,5) link=", byte);
        setup_row_direct(3, 5, byte);

        setup_temp_row(0,1); /* temp. link between nodes 0 and 1 */
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte+1,byte+3); 
        }
        
        if (!check_connection(7)) {
                print_spew("No connection to Node 5.\r\n");
                result.nodes = 4;
                return result; 
        }       
        
        /* We found 6 nodes so far. Now setup all nodes for 6p */
#warning "FIXME we need to find out the correct gateway for 6p" 
        static const u8 conn6_1[] = {
#if !CROSS_BAR_47_56
                0, 4, 2,
                0, 5, 1,
                1, 4, 3,
                1, 5, 3,
                2, 5, 3,
                3, 4, 5,
#else
                0, 4, 2, 0,
                0, 5, 1, 1,
                1, 4, 3, 1,
                1, 5, 3, 0,
                2, 5, 3, 0,
                3, 4, 2, 0,
#endif
        }; 

        setup_row_indirect_group(conn6_1, sizeof(conn6_1)/sizeof(conn6_1[0]));
        
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte,byte+2);
        }
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /*get default link on 7 to 2*/
        print_linkn("(4,2) link=", byte); 
        
        setup_row_local(7,4);
        setup_remote_row_direct(4, 2, byte);
        setup_remote_node(4);  /* Setup the regs on the remote node */
        /* Set indirect connection to 0, to 3 */
        static const u8 conn6_2[] = {
#if !CROSS_BAR_47_56
                4, 0, 2,
                4, 1, 2,
                4, 3, 2,
#else
                4, 0, 2, 0,
                4, 1, 2, 0,
                4, 3, 2, 0,
                4, 5, 2, 0,
#endif
        };      
        
        setup_remote_row_indirect_group(conn6_2, sizeof(conn6_2)/sizeof(conn6_2[0]));
        
        rename_temp_node(4);
        enable_routing(4);

        setup_temp_row(0,1);
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte+1,byte+3);
        }

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 3*/
        print_linkn("(5,3) link=", byte); 
        setup_row_local(7,5);
        setup_remote_row_direct(5, 3, byte);
        setup_remote_node(5);  /* Setup the regs on the remote node */
        
#if !CROSS_BAR_47_56
        /* We need to init link between 4, and 5 direct link */
        val = get_row(4,4);
        byte = ((val>>16) & 0xfe) - link_connection(4,2);
        byte = get_linkn_last_count(byte);
        print_linkn("(4,5) link=", byte & 3);
        
        setup_row_direct(4,5, byte & 0x3);
        setup_temp_row(0,2);
        setup_temp_row(2,4);
        setup_temp_row(4,5);
        check_connection(7); /* to 5*/

#if CONFIG_MAX_CPUS > 6
        /* We need to find out which link is to node5 */
        
        if((byte>>2)==2) { /* one to node5, one to node2, one to node6*/
                val = get_row(7,5);
                if((val>>16) == 1) { /* that link is to node6, because via node 3 node 5 has been set*/
                        val = get_row(4,4);
                        byte = ((val>>16) & 0xfe) - link_connection(4,2);
                        byte = get_linkn_first(byte);
                        print_linkn("-->(4,5) link=", byte);
                        setup_row_direct(4,5,byte);
                        setup_temp_row(4,5);
                        check_connection(7); /* to 5*/
                }
        } 
#endif

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 4*/
        print_linkn("(5,4) link=", byte); 
        setup_remote_row_direct(5,4, byte);
#endif  
        
        /* Set indirect connection to 0, to 3  for indirect we will use clockwise routing */
        static const u8 conn6_3[] = {
#if !CROSS_BAR_47_56
                5, 0, 4,
                5, 2, 4,
                5, 1, 3,
#else
                5, 0, 3, 0,
                5, 2, 3, 0,
                5, 1, 3, 0,
                5, 4, 3, 0,
#endif
        };      
        
        setup_remote_row_indirect_group(conn6_3, sizeof(conn6_3)/sizeof(conn6_3[0]));

/* ready to enable RT for 5 */
        rename_temp_node(5);
        enable_routing(5);      /* enable routing on node 5 (temp.) */

#if 0
        /* We need to do sth about reverse about setup_temp_row (0,1), (2,4), (1, 3), (3,5)
         * It will be done by clear_dead_links 
         */
        for(byte=0; byte<4; byte++) {
                clear_temp_row(byte);
        }
#endif

        /* optimize physical connections - by LYH */
        static const uint8_t opt_conn6[] ={
                2, 4,
                3, 5,
#if !CROSS_BAR_47_56
                4, 5,
#endif
        }; 
        result.needs_reset = optimize_connection_group(opt_conn6, sizeof(opt_conn6)/sizeof(opt_conn6[0]));

        return result;

}

#endif /* CONFIG_MAX_CPUS > 4 */

#if CONFIG_MAX_CPUS > 6

static struct setup_smp_result setup_smp8(int needs_reset)
{
        struct setup_smp_result result;
        u8 byte;
        uint32_t val;

        result.nodes=8;
        result.needs_reset = needs_reset;

        /* Setup and check temporary connection from Node 0 to Node 6 via 2 and 4 to 7 */
        val = get_row(4,4);
#if !CROSS_BAR_47_56
        byte = ((val>>16) & 0xfe) - link_connection(4,5) - link_connection(4,2);
#else
        byte = ((val>>16) & 0xfe) - link_connection(4,2);
#endif

#if TRY_HIGH_FIRST == 1
        byte = get_linkn_last_count(byte); /* Max link to 6*/
        if((byte>>2)==0) { /* We should have two or three coherent links on node 4 for 8p*/
                result.nodes = 6;
                return result;
        }
        byte &= 3; /* bit [3,2] is count-1 or 2*/
#else
        byte = get_linkn_first(byte);  /*Min link to 6*/
#endif
        print_linkn("(4,6) link=", byte);
        setup_row_direct(4, 6, byte);

        /* Setup and check temporary connection from Node 0 to Node 6  through 2, and 4*/
        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte,byte+2); 
        }

        if (!check_connection(7) ) {
                print_spew("No connection to Node 6.\r\n");
                result.nodes = 6;
                return result;
        }
#if !CROSS_BAR_47_56
        /* Setup and check temporary connection from Node 0 to Node 7  through 1, 3, 5*/
        val = get_row(5,5);
        byte = ((val>>16) & 0xfe) - link_connection(5,4) - link_connection(5,3);
        byte = get_linkn_first(byte);
        print_linkn("(5,7) link=", byte);
        setup_row_direct(5, 7, byte);

        setup_temp_row(0,1); /* temp. link between nodes 0 and 1 */
        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte+1,byte+3); 
        }
#else
        val = get_row(4,4);
        byte = ((val>>16) & 0xfe) - link_connection(4,2) - link_connection(4,6);
        byte = get_linkn_first(byte); 
        print_linkn("(4,7) link=", byte); 
        setup_row_direct(4, 7, byte);

        /* Setup and check temporary connection from Node 0 to Node 7 through 2, and 4*/
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte,byte+2); 
        }
        setup_temp_row(4, 7);

#endif

        if (!check_connection(7)) {
                print_spew("No connection to Node 7.\r\n");
                result.nodes = 6;
                return result;
        }


        /* We found 8 nodes so far. Now setup all nodes for 8p */
        static const u8 conn8_1[] = {
#if !CROSS_BAR_47_56
                0, 6, 2,
                /*0, 7, 1,*/
                1, 6, 3,
                /*1, 7, 3,*/
                2, 6, 4,
                /*2, 7, 3,*/
                3, 6, 5,
                /*3, 7, 5,*/
                /*4, 7, 5,*/
#else
                0, 6, 2, 0,
                /*0, 7, 2, 0,*/
                1, 6, 3, 0,
                /*1, 7, 3, 0,*/
                2, 6, 4, 0,
                /*2, 7, 4, 0,*/
                3, 6, 5, 0,
                /*3, 7, 5, 0,*/
#endif
        };

        setup_row_indirect_group(conn8_1,sizeof(conn8_1)/sizeof(conn8_1[0]));

        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte,byte+2);
        }
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 4*/
        print_linkn("(6,4) link=", byte);
        
        setup_row_local(7,6);
        setup_remote_row_direct(6, 4, byte);
        setup_remote_node(6);  /* Setup the regs on the remote node */
        /* Set indirect connection to 0, to 3   */
#warning "FIXME we need to find out the correct gateway for 8p"         
        static const u8 conn8_2[] = {
#if !CROSS_BAR_47_56
                6, 0, 4,
                6, 1, 4,
                6, 2, 4,
                6, 3, 4,
                6, 5, 4,
#else
                6, 0, 4, 0,
                /*6, 1, 5, 0,*/
                6, 2, 4, 0,
                /*6, 3, 5, 0,*/
#endif
        };

        setup_remote_row_indirect_group(conn8_2, sizeof(conn8_2)/sizeof(conn8_2[0]));
        
        rename_temp_node(6);
        enable_routing(6);

#if !CROSS_BAR_47_56
        setup_temp_row(0,1);
        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte+1,byte+3);
        }

        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 5*/
        print_linkn("(7,5) link=", byte); 
        setup_row_local(7,7);
        setup_remote_row_direct(7, 5, byte);

#else
        for(byte=0; byte<4; byte+=2) {
                setup_temp_row(byte,byte+2);
        }
        setup_temp_row(4,7);
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 4*/
        print_linkn("(7,4) link=", byte); 
        setup_row_local(7,7);
        setup_remote_row_direct(7, 4, byte);
        /* till now 4-7, 7-4 done. */
#endif
        setup_remote_node(7);  /* Setup the regs on the remote node */

#if CROSS_BAR_47_56
        /* here init 5, 7 */
        /* Setup and check temporary connection from Node 0 to Node 5  through 1, 3, 5*/
        val = get_row(5,5);
        byte = ((val>>16) & 0xfe) - link_connection(5,3);
        byte = get_linkn_last(byte);
        print_linkn("(5,7) link=", byte); 
        setup_row_direct(5, 7, byte);
        
        setup_temp_row(0,1); /* temp. link between nodes 0 and 1 */
        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte+1,byte+3); 
        }

        if (!check_connection(7)) {
                /* We need to recompute link to 7 */
                val = get_row(5,5);
                byte = ((val>>16) & 0xfe) - link_connection(5,3);
                byte = get_linkn_first(byte);

                print_linkn("-->(5,7) link=", byte);
                setup_row_direct(5, 7, byte);
#if 0
                setup_temp_row(0,1); /* temp. link between nodes 0 and 1 */
                for(byte=0; byte<6; byte+=2) {
                        setup_temp_row(byte+1,byte+3); 
                }
#else
                setup_temp_row(5,7);
#endif
                check_connection(7);
        }
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 5*/
        print_linkn("(7,5) link=", byte);
        setup_remote_row_direct(7, 5, byte);
        /*Till now 57, 75 done */
        
        /* init init 5, 6 */
        val = get_row(5,5);
        byte = ((val>>16) & 0xfe) - link_connection(5,3) - link_connection(5,7);
        byte = get_linkn_first(byte);
        print_linkn("(5,6) link=", byte);
        setup_row_direct(5, 6, byte);

        /* init 6,7 */
        val = get_row(6,6);
        byte = ((val>>16) & 0xfe) - link_connection(6,4);
        byte = get_linkn_last(byte);
        print_linkn("(6,7) link=", byte);
        setup_row_direct(6, 7, byte);

        for(byte=0; byte<6; byte+=2) {
                setup_temp_row(byte,byte+2); 
        }
        setup_temp_row(6,7);

        if (!check_connection(7)) {
                /* We need to recompute link to 7 */
                val = get_row(6,6);
                byte = ((val>>16) & 0xfe) - link_connection(6,4);
                byte = get_linkn_first(byte);
                print_linkn("-->(6,7) link=", byte);

                setup_row_direct(6, 7, byte);
#if 0
                for(byte=0; byte<6; byte+=2) {
                        setup_temp_row(byte,byte+2); /* temp. link between nodes 0 and 2 */
                }
#endif
                setup_temp_row(6,7);
                check_connection(7);
        }
        val = pci_read_config32(NODE_HT(7), 0x6c);
        byte = (val>>2) & 0x3; /* get default link on 7 to 6*/
        print_linkn("(7,6) link=", byte);

        setup_remote_row_direct(7, 6, byte);
        /* Till now 67, 76 done*/

        /* init 6,5 */
        val = get_row(6,6);
        byte = ((val>>16) & 0xfe) - link_connection(6,4) - link_connection(6,7);
        byte = get_linkn_first(byte);
        print_linkn("(6,5) link=", byte);
        setup_row_direct(6, 5, byte);

#endif

#if !CROSS_BAR_47_56
        /* We need to init link between 6, and 7 direct link */
        val = get_row(6,6);
        byte = ((val>>16) & 0xfe) - link_connection(6,4);
        byte = get_linkn_first(byte);
        print_linkn("(6,7) link=", byte);
        setup_row_direct(6,7, byte);

        val = get_row(7,7);
        byte = ((val>>16) & 0xfe) - link_connection(7,5);
        byte = get_linkn_first(byte);
        print_linkn("(7,6) link=", byte);
        setup_row_direct(7,6, byte);
#endif

        /* Set indirect connection to 0, to 3  for indirect we will use clockwise routing */
        static const u8 conn8_3[] = {
#if !CROSS_BAR_47_56
                0, 7, 1,  /* restore it*/
                1, 7, 3,
                2, 7, 3,
                3, 7, 5,
                4, 7, 5,

                7, 0, 6,
                7, 1, 5,
                7, 2, 6,
                7, 3, 5,
                7, 4, 6,
#else
                0, 7, 2, 0, /* restore it*/
                1, 7, 3, 0,
                2, 7, 4, 0,
                3, 7, 5, 0,
                
                6, 1, 5, 0, /*???*/
                6, 3, 5, 0, /*???*/
                
                7, 0, 4, 0,
                7, 1, 5, 0,
                7, 2, 4, 0,
                7, 3, 5, 0,
                4, 5, 7, 0,
                5, 4, 6, 0,
#endif
        };

        setup_row_indirect_group(conn8_3, sizeof(conn8_3)/sizeof(conn8_3[0]));
        
/* ready to enable RT for Node 7 */
        enable_routing(7);      /* enable routing on node 7 (temp.) */
        

        static const uint8_t opt_conn8[] ={
                4, 6,
#if CROSS_BAR_47_56
                4, 7,
                5, 6,
#endif
                5, 7,
                6, 7,
        };
        /* optimize physical connections - by LYH */
        result.needs_reset = optimize_connection_group(opt_conn8, sizeof(opt_conn8)/sizeof(opt_conn8[0]));

        return result;
}

#endif /* CONFIG_MAX_CPUS > 6 */


#if CONFIG_MAX_CPUS > 1

static struct setup_smp_result setup_smp(void)
{
        struct setup_smp_result result;

        print_spew("Enabling SMP settings\r\n");
                
        result = setup_smp2();
#if CONFIG_MAX_CPUS > 2
        result = setup_smp4(result.needs_reset);
#endif
        
#if CONFIG_MAX_CPUS > 4
        result = setup_smp6(result.needs_reset);
#endif

#if CONFIG_MAX_CPUS > 6
        result = setup_smp6(result.needs_reset);
#endif

        print_debug_hex8(result.nodes);
        print_debug(" nodes initialized.\r\n");
        
        return result;

}

static unsigned verify_mp_capabilities(unsigned nodes)
{
        unsigned node, mask;
        
        mask = 0x06; /* BigMPCap */

        for (node=0; node<nodes; node++) {
                mask &= pci_read_config32(NODE_MC(node), 0xe8);
        }
        
        switch(mask) {
#if CONFIG_MAX_CPUS > 2
        case 0x02: /* MPCap    */
                if(nodes > 2) {
                        print_err("Going back to DP\r\n");
                        return 2;
                }
                break;
#endif
        case 0x00: /* Non SMP */
                if(nodes >1 ) {
                        print_err("Going back to UP\r\n");
                        return 1;
                }
                break;
        }
        
        return nodes;

}


static void clear_dead_routes(unsigned nodes)
{
        int last_row;
        int node, row;
#if CONFIG_MAX_CPUS > 6
        if(nodes==8) return;/* don't touch (7,7)*/
#endif
        last_row = nodes;
        if (nodes == 1) {
                last_row = 0;
        }
        for(node = 7; node >= 0; node--) {
                for(row = 7; row >= last_row; row--) {
                        fill_row(node, row, DEFAULT);
                }
        }
        
        /* Update the local row */
        for( node=0; node<nodes; node++) {
                uint32_t val = 0;
                for(row =0; row<nodes; row++) {
                        val |= get_row(node, row);
                }
                fill_row(node, node, (((val & 0xff) | ((val >> 8) & 0xff)) << 16) | 0x0101); 
        }
}
#endif /* CONFIG_MAX_CPUS > 1 */

static void coherent_ht_finalize(unsigned nodes)
{
        unsigned node;
        int rev_a0;
        
        /* set up cpu count and node count and enable Limit
        * Config Space Range for all available CPUs.
        * Also clear non coherent hypertransport bus range
        * registers on Hammer A0 revision.
        */

        print_spew("coherent_ht_finalize\r\n");
        rev_a0 = is_cpu_rev_a0();
        for (node = 0; node < nodes; node++) {
                device_t dev;
                uint32_t val;
                dev = NODE_HT(node);

                /* Set the Total CPU and Node count in the system */
                val = pci_read_config32(dev, 0x60);
                val &= (~0x000F0070);
                val |= ((nodes-1)<<16)|((nodes-1)<<4);
                pci_write_config32(dev, 0x60, val);

                /* Only respond to real cpu pci configuration cycles
                * and optimize the HT settings 
                */
                val=pci_read_config32(dev, 0x68);
                val &= ~((HTTC_BUF_REL_PRI_MASK << HTTC_BUF_REL_PRI_SHIFT) |
                        (HTTC_MED_PRI_BYP_CNT_MASK << HTTC_MED_PRI_BYP_CNT_SHIFT) |
                        (HTTC_HI_PRI_BYP_CNT_MASK << HTTC_HI_PRI_BYP_CNT_SHIFT));
                val |= HTTC_LIMIT_CLDT_CFG | 
                        (HTTC_BUF_REL_PRI_8 << HTTC_BUF_REL_PRI_SHIFT) |
                        HTTC_RSP_PASS_PW |
                        (3 << HTTC_MED_PRI_BYP_CNT_SHIFT) |
                        (3 << HTTC_HI_PRI_BYP_CNT_SHIFT);
                pci_write_config32(dev, 0x68, val);

                if (rev_a0) {
                        print_spew("shit it is an old cup\n");
                        pci_write_config32(dev, 0x94, 0);
                        pci_write_config32(dev, 0xb4, 0);
                        pci_write_config32(dev, 0xd4, 0);
                }
        }

        print_spew("done\r\n");
}

static int apply_cpu_errata_fixes(unsigned nodes, int needs_reset)
{
        unsigned node;
        for(node = 0; node < nodes; node++) {
                device_t dev;
                uint32_t cmd;
                dev = NODE_MC(node);
                if (is_cpu_pre_c0()) {

                        /* Errata 66
                        * Limit the number of downstream posted requests to 1 
                        */
                        cmd = pci_read_config32(dev, 0x70);
                        if ((cmd & (3 << 0)) != 2) {
                                cmd &= ~(3<<0);
                                cmd |= (2<<0);
                                pci_write_config32(dev, 0x70, cmd );
                                needs_reset = 1;
                        }
                        cmd = pci_read_config32(dev, 0x7c);
                        if ((cmd & (3 << 4)) != 0) {
                                cmd &= ~(3<<4);
                                cmd |= (0<<4);
                                pci_write_config32(dev, 0x7c, cmd );
                                needs_reset = 1;
                        }
                        /* Clock Power/Timing Low */
                        cmd = pci_read_config32(dev, 0xd4);
                        if (cmd != 0x000D0001) {
                                cmd = 0x000D0001;
                                pci_write_config32(dev, 0xd4, cmd);
                                needs_reset = 1; /* Needed? */
                        }

                }
                else {
                        uint32_t cmd_ref;
                        /* Errata 98 
                        * Set Clk Ramp Hystersis to 7
                        * Clock Power/Timing Low
                        */
                        cmd_ref = 0x04e20707; /* Registered */
                        cmd = pci_read_config32(dev, 0xd4);
                        if(cmd != cmd_ref) {
                                pci_write_config32(dev, 0xd4, cmd_ref );
                                needs_reset = 1; /* Needed? */
                        }
                }
        }
        return needs_reset;
}

static int optimize_link_read_pointers(unsigned nodes, int needs_reset)
{
        unsigned node;
        for(node = 0; node < nodes; node++) {
                device_t f0_dev, f3_dev;
                uint32_t cmd_ref, cmd;
                int link;
                f0_dev = NODE_HT(node);
                f3_dev = NODE_MC(node);
                cmd_ref = cmd = pci_read_config32(f3_dev, 0xdc);
                for(link = 0; link < 3; link++) {
                        uint32_t link_type;
                        unsigned reg;
                        /* This works on an Athlon64 because unimplemented links return 0 */
                        reg = 0x98 + (link * 0x20);
                        link_type = pci_read_config32(f0_dev, reg);
                        if ((link_type & 7) == 3) { 
                                cmd &= ~(0xff << (link *8));
                                cmd |= 0x25 << (link *8);
                        }
                }
                if (cmd != cmd_ref) {
                        pci_write_config32(f3_dev, 0xdc, cmd);
                        needs_reset = 1;
                }
        }
        return needs_reset;
}

static int setup_coherent_ht_domain(void)
{
        struct setup_smp_result result;

        enable_bsp_routing();

#if CONFIG_MAX_CPUS > 1
        result = setup_smp();
        result.nodes = verify_mp_capabilities(result.nodes);
        clear_dead_routes(result.nodes);
#else
        result.nodes = 1;
        result.needs_reset = 0;
#endif

        if (result.nodes == 1) {
                setup_uniprocessor();
        } 
        coherent_ht_finalize(result.nodes);
        result.needs_reset = apply_cpu_errata_fixes(result.nodes, result.needs_reset);
        result.needs_reset = optimize_link_read_pointers(result.nodes, result.needs_reset);
        return result.needs_reset;
}