Re: [ECOS] How to access PCI memory(HELP)....

[Nick Garnett <nickg@cygnus.co.uk>]

"Ling Su" <lingsu@palmmicro.com> writes:

> Why need I set HAL_PCI_ALLOC_BASE_MEMORY to 0x90000000, originally it is
> 0x0, which means mapp the memory from the beginning, what is the rational to
> add a 0x9000_0000 offset?

Since the 4372 is already mapped at 0x80000000 in the PCI space, any
further allocations must be contiguous with that, since the aperture
onto the PCI address space starts there.

> Nick, I follow your suggestion, basically I changed three things,
> (1). HAL_PCI_PHYSICAL_MEMORY_BASE set to 0xD0000000
> (2). HAL_PCI_ALLOC_BASE_MEMORY set to 0x90000000
> (3). increase NUMB_PG to 16
> 


>  BAR[0]    0x09000000 / probed size 0xFFF00000 / CPU addr 0xD9000000

These look like the value of HAL_PCI_ALLOC_BASE_MEMORY is
0x09000000 rather than 0x90000000 - a missing zero most probably.
Also the value of CPU addr suggests that HAL_PCI_PHYSICAL_MEMORY_BASE
should be 0x40000000, since that is the offset between a PCI address
and its virtual address in the CPU.

So try these values:

HAL_PCI_PHYSICAL_MEMORY_BASE = 0x40000000
HAL_PCI_ALLOC_BASE_MEMORY = 0x90000000
NUMB_PG = 16


Let me know what happens.

-- 
Nick Garnett, eCos Kernel Architect
Red Hat, Cambridge, UK