There are some PowerPC SoCs that do odd things with the MAL handling.  In
order to accommodate them, we need to introduce a feature mechanism that is
similar to the existing emac_has_feature function.

This adds a feature variable to the mal_instance structure, and adds a
mal_has_feature function.  Two features are defined and are guarded
by Kconfig options that are selected by the affected platforms.

MAL_FTR_CLEAR_ICINSTAT is used for platforms that need to clear the
interrupt bits in the ICINTSTAT SDR for txeob/rxeob.  This is common
on MAL implementations that have interrupt coalescing.

MAL_FTR_COMMON_ERR_INT is used for platforms that have SERR, TXDE,
and RXDE OR'd into a single interrupt bit.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

Some PowerPC 40x chips have errata that force us not to use the integrated
flow control.  We have the feature defined, but it currently can't be used
because it is never added to EMAC_FTRS_POSSIBLE.

This adds a Kconfig option for affected platforms to select and puts the
feature in the EMAC_FTRS_POSSIBLE list.  This is set for PowerPC 405EZ
platforms as well.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>

The ibm_newemac driver requires ether_crc to be defined.  Apparently it is
possible to generate a .config without CONFIG_CRC32 set which causes the
following link errors if IBM_NEW_EMAC is selected:

  LD      .tmp_vmlinux1
drivers/built-in.o: In function `emac_hash_mc':
core.c:(.text+0x2f524): undefined reference to `crc32_le'
core.c:(.text+0x2f528): undefined reference to `bitrev32'
make: *** [.tmp_vmlinux1] Error 1

This patch has IBM_NEW_EMAC select CRC32 so we don't hit this error.
Signed-off-by: NJosh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

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>