On 09/19/2011 03:32 PM, Jan Kiszka wrote:
> It's opt-in. If a device sets
> MemoryRegionOps::impl.{min,max}_access_size = 1, it will only be fed
> byte accesses (the core will take care of breaking apart larger
> writes). If it sets MemoryRegionOps::impl.{min,max}_access_size = 4, it
> will only get long accesses (and the core will/should shift/mask or
> RMW). Refusing illegal access sizes is done using
> MemoryRegionOps::valid. Most of this is unimplemented unfortunately.
That makes sense (for non-old_portio users).
The trick of having a way to register N callbacks with one shot is worth
growing. Ideally each register in a BAR would have a callback and we'd
do something like
MemoryRegionOps mydev_ops = {
.registers = {
{ MYDEV_REG_x, 4, 4, mydev_reg_x_read, mydev_reg_x_write, },
...
},
}
with hints to the core like "this register sits at this offset, use it
for reads instead of a callback", or, "this is a read-only register".
--
error compiling committee.c: too many arguments to function
