The reference implementation of the PCI initialization code almost
everywhere contain this fragile loop of "a few usecs", and its
use of volatile variables to delay a number of bus cycles is indeed
uncertain.
Reading the manual "Integrator/AP Users Guide", page 5-15 it is
clearly stated:
"Wait until 230ms after the end of the reset period before
accessing V360EPC internal registers. The V360EPC supports the
use of a serial configuration PROM and the software must wait for
the device to detect the absence of this PROM before accessing any
registers. The required delay is a function of the PCI Clock, but
at the lower frequency (25MHz) is 230ms".
So let's simply wait 230ms per the spec.
This solves the compilation error that looked like this:
pci.c: In function ‘pci_init_board’:
pci.c:286:18: warning: variable ‘j’ set but not used
Reported-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij
fca94c3fd5