Bounine, Alexandre wrote:

Micha Nelissen [off-list ref] wrote:

quoted

Alexandre Bounine wrote:
How can you say this? The two variables have different meanings, this
logically implies you can't merge them. So how do you say 'this does

not

quoted

prevent us from ...' without providing a reason?

Looks like I formulated it bad - better would be: they have different
interpretation by hardware but logically in RapidIO they have single
role - destid/hopcount are a device coordinates in the RIO network used
to access that device.

They are logically different as well (for a non-host).

rswitch->destid with hopcount is the way to reach that switch.

rswitch->rdev->destid should be the id associated with a given switch, 
so that every (processor) device can agree what id some switch has. For 
a non-host, the path to reach a switch may use a different id than the 
switch itself has; it's just the id by which it was discovered.

However, it's possible to fix that by fixing the id+hopcount once the 
switch is found using the path with its own id: then you know the right 
hopcount.

quoted

can be defined to point to the switch that a given rio_dev is

connected

quoted

to. This is useful for quick lookups. How else can to know to which
switch a given device is connected?

rdev->rswitch is not a pointer to the entire switch device object - it
is a pointer to the switch specific extension associated with given
rio_dev (if applicable). There is no other role for rdev->rswitch.

I know this, it doesn't answer my question.

Why would you keep a pointer to device data extension instead of the
pointer to attached device object itself?

There is no particular reason, but this is a useful way to define the 
fields that are there.

My point is, now that you remove the pointer field, that information (to 
which switch is a particular device connected) cannot be stored in this 
way, so do you have an alternative proposal for that? Maybe add a new field.

BTW, I have back and forward links added in previous patches and only
one link that may be added later is a forward link from mport to the
attached rio_dev (ptr to rio_switch will not work here because it can be
switchless connection). But this reference has to be added into
rio_mport.

Possible, but I suggest to put it in the rio_net: fields rdev_host, and 
rdev_self. You can see it in the patch I sent you.

Micha