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Altera_Forum
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17 years ago

Linux with MMU on NEEK

Hi, all. I'm testing Linux MMU version, on my NEEK. http://www.nioswiki.com/linux It works fine and I can use "bash" shell. This is the evident proof that we are using the true 'fo...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

Hi,

The previous version of 'kgdb' will not read the Nios's registers r17~r23.

http://www.alteraforum.com/forum/showpost.php?p=77003&postcount=20

But the kernel sometimes uses those for the locations of its local variables, so we must read and write the registers r17~r23. To do this, please add codes to the file 'entry.S' 


handle_diverror:
    call handle_illegal_c
    br ret_from_exception
# ifdef CONFIG_KGDB
handle_kgdb_breakpoint:
    SAVE_SWITCH_STACK        // <-- Add this.
    call kgdb_breakpoint_c
    RESTORE_SWITCH_STACK        // <-- Add this.
    br ret_from_exception# endif
and modify the file 'kgdb.c' of the nios arch like 


void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
    gdb_regs = 0;
    gdb_regs = regs->r1;
    gdb_regs = regs->r2;
    gdb_regs = regs->r3;
    gdb_regs = regs->r4;
    gdb_regs = regs->r5;
    gdb_regs = regs->r6;
    gdb_regs = regs->r7;
    gdb_regs = regs->r8;
    gdb_regs = regs->r9;
    gdb_regs = regs->r10;
    gdb_regs = regs->r11;
    gdb_regs = regs->r12;
    gdb_regs = regs->r13;
    gdb_regs = regs->r14;
    gdb_regs = regs->r15;
    gdb_regs = regs->ra;
    gdb_regs = regs->fp;
    gdb_regs = regs->sp;
    gdb_regs = regs->gp;
    gdb_regs = regs->estatus;
    gdb_regs = regs->ea;
    gdb_regs = regs->ea;
    {
        struct switch_stack *swregs = (struct switch_stack *)regs;
        swregs--;
        gdb_regs = swregs->r16;
        gdb_regs = swregs->r17;
        gdb_regs = swregs->r18;
        gdb_regs = swregs->r19;
        gdb_regs = swregs->r20;
        gdb_regs = swregs->r21;
        gdb_regs = swregs->r22;
        gdb_regs = swregs->r23;
    }
}
void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs)
{
    regs->r1 = gdb_regs;
    regs->r2 = gdb_regs;
    regs->r3 = gdb_regs;
    regs->r4 = gdb_regs;
    regs->r5 = gdb_regs;
    regs->r6 = gdb_regs;
    regs->r7 = gdb_regs;
    regs->r8 = gdb_regs;
    regs->r9 = gdb_regs;
    regs->r10 = gdb_regs;
    regs->r11 = gdb_regs;
    regs->r12 = gdb_regs;
    regs->r13 = gdb_regs;
    regs->r14 = gdb_regs;
    regs->r15 = gdb_regs;
    regs->ra = gdb_regs;
    regs->fp = gdb_regs;
    regs->sp = gdb_regs;
    regs->gp = gdb_regs;
    regs->estatus = gdb_regs;
    regs->ea = gdb_regs;
    {
        struct switch_stack *swregs = (struct switch_stack *)regs;
        swregs--;
        swregs->r16 = gdb_regs;
        swregs->r17 = gdb_regs;
        swregs->r18 = gdb_regs;
        swregs->r19 = gdb_regs;
        swregs->r20 = gdb_regs;
        swregs->r21 = gdb_regs;
        swregs->r22 = gdb_regs;
        swregs->r23 = gdb_regs;
    }
}
.

Kazu