net: Fix new EMAC driver for NAPI changes

This fixes the new EMAC driver for the NAPI updates. The previous patch
by Roland Dreier (already applied) to do that doesn't actually work. This
applies on top of it makes it work on my test Ebony machine.

This patch depends on "net: Add __napi_sycnhronize() to sync with napi poll"
posted previously.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

With the base stored in dcr_host_t, there's no need for callers to pass
the dcr_n into dcr_unmap(). In fact this removes the possibility of them
passing the incorrect value, which would then be iounmap()'ed.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Now that all users of dcr_read()/dcr_write() add the dcr_host_t.base, we
can save them the trouble and do it in dcr_read()/dcr_write().

As some background to why we just went through all this jiggery-pokery,
benh sayeth:

 Initially the goal of the dcr_read/dcr_write routines was to operate like
 mfdcr/mtdcr which take absolute DCR numbers. The reason is that on 4xx
 hardware, indirect DCR access is a pain (goes through a table of
 instructions) and it's useful to have the compiler resolve an absolute DCR
 inline.

 We decided that wasn't worth the API bastardisation since most places
 where absolute DCR values are used are low level 4xx-only code which may
 as well continue using mfdcr/mtdcr, while the new API is designed for
 device "instances" that can exist on 4xx and Axon type platforms and may
 be located at variable DCR offsets.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Now that dcr_host_t contains the base address, we can use that in the
ibm_newemac code, rather than storing it separately.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

... since that sucker is not 32bit-only and on 64bit skb->tail is an
offset, not a pointer.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit da3dedd9 ("[NET]: Make NAPI polling independent of struct
net_device objects.") changed the interface to NAPI polling.  Fix up
the ibm_newemac driver so that it works with this new interface.  This
is actually a nice cleanup because ibm_newemac is one of the drivers
that wants to have multiple NAPI structures for a single net_device.

Compile-tested only as I don't have a system that uses the ibm_newemac
driver.  This conversion the conversion for the ibm_emac driver that
was tested on real PowerPC 440SPe hardware.
Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NRoland Dreier <rolandd@cisco.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Fix an obvious typo in emac_xmit_finish.
Signed-off-by: NValentine Barshak <vbarshak@ru.mvista.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Based on BenH's earlier work, this is a new version of the EMAC driver
for the built-in ethernet found on PowerPC 4xx embedded CPUs.  The
same ASIC is also found in the Axon bridge chip.  This new version is
designed to work in the arch/powerpc tree, using the device tree to
probe the device, rather than the old and ugly arch/ppc OCP layer.

This driver is designed to sit alongside the old driver (that lies in
drivers/net/ibm_emac and this one in drivers/net/ibm_newemac).  The
old driver is left in place to support arch/ppc until arch/ppc itself
reaches its final demise (not too long now, with luck).

This driver still has a number of things that could do with cleaning
up, but I think they can be fixed up after merging.  Specifically:
	- Should be adjusted to properly use the dma mapping API.
Axon needs this.
	- Probe logic needs reworking, in conjuction with the general
probing code for of_platform devices.  The dependencies here between
EMAC, MAL, ZMII etc. make this complicated.  At present, it usually
works, because we initialize and register the sub-drivers before the
EMAC driver itself, and (being in driver code) runs after the devices
themselves have been instantiated from the device tree.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Signed-off-by: NJeff Garzik <jeff@garzik.org>