Hi I have to reply to my mail. It was a cache related problem. I didn't initialize cache correctly.
Thank you for listening to my problem. - Sangmoon Kim - ----- Original Message ----- From: "Sangmoon Kim" <[EMAIL PROTECTED]> To: <linuxppc-embedded at lists.linuxppc.org> Sent: Wednesday, December 19, 2001 3:37 PM Subject: Re: MPC755 Porting Problem > > Thank you for response. > > I solved the problem. > After the RFI, MMU begins to work. > I tried to access the phiscal address in serial_hello(). > While the address is mapped to another area by BAT. > > I think, It's something like the uncertainty theory. > We cannot watch a phenominan precisely, because the action of watching > affects the phenominan. > > Any way, I encountered another problem. > I'm porting linux on my MPC755 board. > It is the dump message of xmon after the kernel was crashed during > initialization. > > vector: 400 at pc = 20002024, lr = 20002024 > msr = 40001032, sp = c0130320 [c0130270] > current = c012e420, pid = 0, comm = swapper > mon> > > The point where it happens was in __alloc_bootmem_core. > After the following function. > memset(ret, 0, size); > where > ret = 0xC01D9000 > size = 0x200040 > > Where can I start to debug this. > > Thanks in advance. > - Sangmoon Kim - > > ----- Original Message ----- > From: "Babic Stefano" <Stefano.Babic at icn.siemens.de> > To: <linuxppc-embedded at lists.linuxppc.org> > Sent: Wednesday, December 19, 2001 1:36 AM > Subject: AW: MPC755 Porting Problem > > > > > > Hi, > > > > we have already ported linux on our board based on MPC 755. The kernel is > > set at 0xc0000000, as you can see on arch/ppc/Makefile > > (KERNELLOAD=0xc0000000). We did not want to change it, because it is quite > > a standard value for external tools. > > We are using the boot loader in mbx directory (or mbxboot, depending on > > version you are using), so we are using really the head_8260.S file instead > > of head.S. > > From the sources of the loader it seems necessary to load the kernel in > > high memory range (physical address), in any case greater as 0x400000 > > (which address is not important). Then the loader remapped it to 0xc0000000. > > For us it is not a problem to load the kernel at a higher address and in > > this way the loader can correctly start the kernel. > > > > I hope it could be help. > > > > stefano babic > > > > -----Ursprungliche Nachricht----- > > Von: Sangmoon Kim [mailto:dogoil at etinsys.com] > > Gesendet: Samstag, 15. Dezember 2001 07:24 > > An: linuxppc-embedded at lists.linuxppc.org > > Betreff: MPC755 Porting Problem > > > > > > > > Hi? > > I'm porting linux for a MPC755 board which I designed, > > and having some trouble with arch/ppc/kernel/head.S > > I load the kernel at phiscal address 0x00000000 > > and head.S seams to relocate it to 0xc0000000 > > The code is like this > > > > mfmsr r0 /* Inst and data addr translations are disabled */ > > ori r0,r0,MSR_DR|MSR_IR /* enable Inst and data addr > > translation */ > > mtspr SRR1,r0 > > lis r0,start_here at h > > ori r0,r0,start_here at l > > mtspr SRR0,r0 > > SYNC > > RFI /* jump to SRR0 */ > > > > start_here: > > /* Call setup_cpu for CPU 0 */ > > li r3,0 /* data offset */ > > li r24,0 /* cpu# */ > > bl call_setup_cpu > > > > It is running at base address 0x00000000. > > start_here is at address 0xc000369c. > > And the IBAT0, and DBAT0 is C0001FFE-00000002. > > So after RFI it should go to start_here. > > > > But If I insert some code like 'bl serial_hello', > > which prints hello? to serial console after start_here. > > It never prints a message. It works before the RFI. > > > > Where can I start to debug it? > > > > serial_hello is like this. > > > > void > > serial_hello() > > { > > serial_putc(SCC_A_ADDRESS,'h'); > > serial_putc(SCC_A_ADDRESS,'e'); > > serial_putc(SCC_A_ADDRESS,'l'); > > serial_putc(SCC_A_ADDRESS,'l'); > > serial_putc(SCC_A_ADDRESS,'o'); > > serial_putc(SCC_A_ADDRESS,'?'); > > serial_putc(SCC_A_ADDRESS,'\n'); > > serial_putc(SCC_A_ADDRESS,'\r'); > > } > > Thanks in advance. > > - Sangmoon Kim - > > > > > > > > > > > ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
