Current implementation of descriptor init procedure only takes
care about setting/clearing ownership flag in "des0"/"des1"
fields while it is perfectly possible to get unexpected bits
set because of the following factors:

 [1] On driver probe underlying memory allocated with
     dma_alloc_coherent() might not be zeroed and so
     it will be filled with garbage.

 [2] During driver operation some bits could be set by SD/MMC
     controller (for example error flags etc).

And unexpected and/or randomly set flags in "des0"/"des1"
fields may lead to unpredictable behavior of GMAC DMA block.

This change addresses both items above with:

 [1] Use of dma_zalloc_coherent() instead of simple
     dma_alloc_coherent() to make sure allocated memory is
     zeroed. That shouldn't affect performance because
     this allocation only happens once on driver probe.

 [2] Do explicit zeroing of both "des0" and "des1" fields
     of all buffer descriptors during initialization of
     DMA transfer.

And while at it fixed identation of dma_free_coherent()
counterpart as well.
Signed-off-by: NAlexey Brodkin <abrodkin@synopsys.com>
Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Cc: arc-linux-dev@synopsys.com
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch tidies up the code. I have run Linden (and verified with checkpatch)
many part of the driver trying to reorganize some sections respecting the
codying-style rules in the points where it was not done.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is to support the extend descriptors available
in the chips newer than the 3.50.

In case of the extend descriptors cannot be supported,
at runtime, the driver will continue to work using the old style.

In detail, this support extends the main descriptor structure
adding new descriptors: 4, 5, 6, 7. The desc4 gives us extra
information about the received ethernet payload when it is
carrying PTP packets or TCP/UDP/ICMP over IP packets.
The descriptors 6 and 7 are used for saving HW L/H timestamps (PTP).

V2: this new version removes the Koption added in the first implementation
because all the checks now to verify if the extended descriptors are
actually supported happen at probe time.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds "#ifndef __<header>_H" for protecting header from double
inclusion.
Signed-off-by: NRayagond Kokatanur <rayagond@vayavyalabs.com>
Hacked-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch updates the normal descriptor structure
to work fine on new GMAC Synopsys chips.

Normal descriptors were designed on the old MAC10/100
databook 1.91 where some bits were reserved: for example
the tx checksum insertion and rx checksum offload.

The patch maintains the back-compatibility with old
MAC devices (tested on STx7109 MAC10/100) and adds new
fields that actually new GMAC devices can use.

For example, STx7109 (MAC10/100) will pass from the platform
  tx_coe = 0, enh_desc = 0, has_gmac = 0.
A platform like Loongson1B (GMAC) will pass:
  tx_coe = 1, enh_desc = 0, has_gmac = 1.

Thanks to Kelvin, he enhanced the normal descriptors for
GMAC (on MIPS Loongson1B platform).
Signed-off-by: NKelvin Cheung <keguang.zhang@gmail.com>
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the STMicroelectronics driver into driver/net/ethernet/stmicro/ and
make the necessary Kconfig and Makefile changes.

CC: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Use dwmac1000 naming instead of gmac.
The patch also splits the gmac.c file in two new ones:
dwmac1000_core.c and dwmac1000_dma.c.
This could actually help on some architectures where different
DMA engines are used.
Signed-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the driver for the ST MAC 10/100/1000 on-chip Ethernet
controllers (Synopsys IP blocks).

Driver documentation:
 o http://stlinux.com/drupal/kernel/network/stmmac
Revisions:
 o http://stlinux.com/drupal/kernel/network/stmmac-driver-revisions
Performances:
 o http://stlinux.com/drupal/benchmarks/networking/stmmacSigned-off-by: NGiuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>