Hi,
I've been trying to get SRAM working with ppcboot v 2.0. My SRAM is a
Samsung K1S321615M UtRAM - we are using this due to it's high capacity
and low noise.
I am using (largely butchered) code based on the gen860t.
Currently I have it configured in ppcboot on CS2:
#define BR2 0x00000081
#define OR2 0xfc000100
and my upm table is:
0x00f3fc04, 0x00f3cc04, 0x00f3cc04, 0x10f3ec04,
0xf1f7fc04, 0xfffffc04, 0x0fffcc24, 0x0fffcc04,
0x08ffcc00, 0x03ffcc4c, 0x08ffcc00, 0x03ffcc4c,
0x08ffcc00, 0x03ffcc4c, 0x08ffcc00, 0x33ffcc47,
0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff,
0xffffffff, 0xffffffff, 0xffffcc04, 0xc0ffdc04,
0x00ff4c04, 0x00ffcc04, 0x00ffcc04, 0x10ffec04,
0xf1fffc04, 0xfffffc04, 0x0fafcc04, 0x0cafcc00,
0x01afcc4c, 0x0cafcc00, 0x01afcc4c, 0x0cafcc00,
0x01afcc4c, 0x0cafcc00, 0x31bfcc43, 0xffffffff,
0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff,
0xffffffff, 0xffffffff, 0xc0ffcc84, 0xfffffc05,
0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff,
0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff,
0xffffffff, 0xffffffff, 0x33ffcc07, 0xffffffff,
0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff
from mcuinit.
dumping variables, i have MAMR at 0x00000000 and MPTPR at 0x0000 (i
have not set MAR to anything tho)
i have also made sure that my MCR has been set to CS2 -> to upmconfig()
in cpu/mpc8xx/cpu.c i have modified the MCR line:
memctl->memc_mcr = addr | upm | 0x00004100;
with all this in place, I am quite certain that I have turned off the
refresh timers associated with UPMA, however, ppcboot still refuses to
copy successfully into SRAM.
I tried to set a breakpoint at the "relocate_code" so by that time it
should have configured the UPMA table, however, trying to even do a
set {int} 0x0 = 0xaaaaaaaa
does not work.
AFAIK, it also does configure the UPMA table before setting or2 and
br2.
With the same parameters outlined above, I have been able to enter the
same things using GDB - i have written macros to enter in the mdr/mcr
variables as well as configure the BRx and ORx (I can write and read
from SRAM).
We have thought about using GPCM, but due to the SRAM requiring bank
select functionality, it is a non-option.
Can anyone help me with this problem?? Has anyone used similar
technology - no DRAM??
Thanks in advance,
My Hong Vuong
