mpc5644a MMU setup

yangzhao — Mon, 11 Mar 2019 09:26:55 GMT

Dear FAE,

I Want to set up MMU of mpc5644a, the complier is WR Diab v5.9.3, after startup code(crt0.s), i try to initial the TLBs

as below, but it run with error to exception after first call CalcTLBEntry, the protype of function is as attached.

my question :

(1) what i need to do before initial MMU in crt0.s?

(2) about the problem , is any suggestion?

thanks for your reply!

void main(void)
{
           CalcTLBEntry (TLBNr0, TLBValid, PorcessID0, TS0, Size64KByte , 0x00000000, 0x00000000, 0);//first 64kb
          CalcTLBEntry (TLBNr1, TLBValid, PorcessID0, TS0, Size64KByte , 0x00010000, 0x00010000, 0);
           CalcTLBEntry (TLBNr2, TLBValid, PorcessID0, TS0, Size64KByte , 0x00020000, 0x00020000, 0);
           CalcTLBEntry (TLBNr3, TLBValid, PorcessID0, TS0, Size64KByte , 0x00030000, 0x00030000, 1);//for Cal_RP


          CalcTLBEntry (TLBNr4, TLBValid, PorcessID0, TS0, Size256KByte , 0x00040000, 0x00040000, 1);//
           CalcTLBEntry (TLBNr5, TLBValid, PorcessID0, TS0, Size256KByte , 0x00080000, 0x00080000, 1);//
          CalcTLBEntry (TLBNr6, TLBValid, PorcessID0, TS0, Size256KByte , 0x000C0000, 0x000C0000, 1);//

           CalcTLBEntry (TLBNr7, TLBValid, PorcessID0, TS0, Size1MByte , 0x00100000, 0x00100000, 1);//
          CalcTLBEntry (TLBNr8, TLBValid, PorcessID0, TS0, Size256KByte , 0x40000000, 0x40000000, 1);//???? not sure

Re: mpc5644a MMU setup

lukaszadrapa — Tue, 12 Mar 2019 10:00:01 GMT

Hi,

MMU is already initialized by BAM. You can find default configuration in the reference manual:

If you are going the reconfigure the TLB entries, you need to be aware of these settings. MMU is active all the time, it can't be disabled. So, you must be very careful to not cut a branch you are sitting on.

Where does it crash exactly? And where the code is running from (which address)?

Regards,

Lukas

topic Re: mpc5644a MMU setup in MPC5xxx

mpc5644a MMU setup

Re: mpc5644a MMU setup