[LinuxBIOS] lb on pd10000

bios at lists.actweb.info bios at lists.actweb.info
Sun Jul 2 02:24:25 CEST 2006

Hi folks,

Ok, ive had a play around with the code for LB to see if i can find where its failing and have found the following :-

in file : src/northbridge/via/vt8623/raminit.c

I added a couple of line to show were in the file its crashing :-

        /* setup cpu */
        print_debug("vt8623 init step 2\r\n");
    DRAM MA Map Type  Device 0  Offset 58

    Determine memory addressing based on the module's memory technology and
    arrangement.  See Table 4-9 of Intel's 82443GX datasheet for details.

    Bank 1/0 MA map type   58[7-5]
    Bank 1/0 command rate  58[4]
    Bank 3/2 MA map type   58[3-1]
    Bank 3/2 command rate  58[0]

    Read SPD byte 17, Number of banks on SDRAM device.
        print_debug("vt8623 init step 3\r\n");
        c = 0;
        b = smbus_read_byte(0xa0,17);
        print_debug("vt8623 init step 4\r\n");
        print_val("Detecting Memory\r\nNumber of Banks ",b);
        print_debug("vt8623 init step 5\r\n");
        if( b != 2 ){            // not 16 Mb type

    Read SPD byte 3, Number of row addresses.

At line 103 (aprox, as ive added some lines for debug as u can see)
the print_debug("vt8623 init step 3\r\n"); statment works ok
BUT I NEVER GET THE 'step 4' debug statments outputting
so i can assume (and PLEASE correct me if im wrong, or if u recon the lines ive added are the cause)
the the bad line is :

 b = smbus_read_byte(0xa0,17);

Ok, after finding this line, i hunted for the source for smbus_read_byte which i belive is in :
(am i corect in thinking this??????)
Im not sure because i edited the file starting at line 151 and added in my debug lines as follows :-

static int smbus_read_byte(unsigned device, unsigned address)
        print_debug("smbus_read_byte start\r\n");
        unsigned char global_control_register;
        unsigned char global_status_register;
        unsigned char byte;

        print_debug("smbus_read_byte step 2\r\n");
        if (smbus_wait_until_ready() < 0) {
                if (smbus_wait_until_ready() < 0) {
                        return -2;
        print_debug("smbus_read_byte step 3\r\n");

        /* setup transaction */
        /* disable interrupts */
        print_debug("smbus_read_byte step 4\r\n");
        /* set the device I'm talking too */
        outb(((device & 0x7f) << 1) | 1, SMBUS_IO_BASE + SMBXMITADD);
        print_debug("smbus_read_byte step 5\r\n");
        /* set the command/address... */
        outb(address & 0xFF, SMBUS_IO_BASE + SMBHSTCMD);
        print_debug("smbus_read_byte step 6\r\n");
        /* set up for a byte data read */
        outb((inb(SMBUS_IO_BASE + SMBHSTCTL) & 0xe3) | (0x2 << 2), SMBUS_IO_BAS$
        print_debug("smbus_read_byte step 7\r\n");

        /* clear any lingering errors, so the transaction will run */
        print_debug("smbus_read_byte step 8\r\n");

        /* clear the data byte... */
        outb(0, SMBUS_IO_BASE + SMBHSTDAT0);
        print_debug("smbus_read_byte step 9\r\n");

        /* start a byte read, with interrupts disabled */
        outb((inb(SMBUS_IO_BASE + SMBHSTCTL) | 0x40), SMBUS_IO_BASE + SMBHSTCTL$
        print_debug("smbus_read_byte step 10\r\n");
        /* poll for it to start */
        if (smbus_wait_until_active() < 0) {
                return -4;
        print_debug("smbus_read_byte step 11\r\n");

        /* poll for transaction completion */
        if (smbus_wait_until_done() < 0) {
                return -3;

        print_debug("smbus_read_byte step 12\r\n");
        /* Ignore the Host Busy & Command Complete ? */
        global_status_register = inb(SMBUS_IO_BASE + SMBHSTSTAT) & ~((1 << 1) |$
        print_debug("smbus_read_byte step 13\r\n");

        /* read results of transaction */
        byte = inb(SMBUS_IO_BASE + SMBHSTDAT0);
        print_debug("smbus_read_byte step 14\r\n");

        if (global_status_register != 0) {
                return -1;
        print_debug("smbus_read_byte step 15\r\n");
        return byte;

Unfortunatly NOTHING EXTRA was displayed via the serial port :(
So, first, is this the write file that im editing to find were the problem is occuring?
second, if so, why didnt i get at leaste the first print_debug before anything else was run in the routine?
if its not the correct file, which file should i edit?
Is this all necisarry, or has someone else already done all this, and got a solution :)

One last thing, am i correct in thinking that simply going into src/targets/via/epia-m/epia-m/ and running 'make clean', 'make'
is enough to recompile all the routines (including the southbridge stuff)?


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