dma_map_single() may fail if an IOMMU or swiotlb is in use, so
we need to check for this.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently we try to clear EDRRR and EDTRR and immediately continue to
free buffers.  This is unsafe because:

- In general, register writes are not serialised with DMA, so we still
  have to wait for DMA to complete somehow
- The R8A7790 (R-Car H2) manual states that the TX running flag cannot
  be cleared by writing to EDTRR
- The same manual states that clearing the RX running flag only stops
  RX DMA at the next packet boundary

I applied this patch to the driver to detect DMA writes to freed
buffers:

> --- a/drivers/net/ethernet/renesas/sh_eth.c
> +++ b/drivers/net/ethernet/renesas/sh_eth.c
> @@ -1098,7 +1098,14 @@ static void sh_eth_ring_free(struct net_device *ndev)
>  	/* Free Rx skb ringbuffer */
>  	if (mdp->rx_skbuff) {
>  		for (i = 0; i < mdp->num_rx_ring; i++)
> +			memcpy(mdp->rx_skbuff[i]->data,
> +			       "Hello, world", 12);
> +		msleep(100);
> +		for (i = 0; i < mdp->num_rx_ring; i++) {
> +			WARN_ON(memcmp(mdp->rx_skbuff[i]->data,
> +				       "Hello, world", 12));
>  			dev_kfree_skb(mdp->rx_skbuff[i]);
> +		}
>  	}
>  	kfree(mdp->rx_skbuff);
>  	mdp->rx_skbuff = NULL;

then ran the loop:

    while ethtool -G eth0 rx 128 ; ethtool -G eth0 rx 64; do echo -n .; done

and 'ping -f' toward the sh_eth port from another machine.  The
warning fired several times a minute.

To fix these issues:

- Deactivate all TX descriptors rather than writing to EDTRR
- As there seems to be no way of telling when RX DMA is stopped,
  perform a soft reset to ensure that both DMA enginess are stopped
- To reduce the possibility of the reset truncating a transmitted
  frame, disable egress and wait a reasonable time to reach a
  packet boundary before resetting
- Update statistics before resetting

(The 'reasonable time' does not allow for CS/CD in half-duplex
mode, but half-duplex no longer seems reasonable!)
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If RX traffic is overflowing the FIFO or DMA ring, logging every time
this happens just makes things worse.  These errors are visible in the
statistics anyway.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In order to stop the RX path accessing the RX ring while it's being
stopped or resized, we clear the interrupt mask (EESIPR) and then call
free_irq() or synchronise_irq().  This is insufficient because the
interrupt handler or NAPI poller may set EESIPR again after we clear
it.  Also, in sh_eth_set_ringparam() we currently don't disable NAPI
polling at all.

I could easily trigger a crash by running the loop:

   while ethtool -G eth0 rx 128 && ethtool -G eth0 rx 64; do echo -n .; done

and 'ping -f' toward the sh_eth port from another machine.

To fix this:
- Add a software flag (irq_enabled) to signal whether interrupts
  should be enabled
- In the interrupt handler, if the flag is clear then clear EESIPR
  and return
- In the NAPI poller, if the flag is clear then don't set EESIPR
- Set the flag before enabling interrupts in sh_eth_dev_init() and
  sh_eth_set_ringparam()
- Clear the flag and serialise with the interrupt and NAPI
  handlers before clearing EESIPR in sh_eth_close() and
  sh_eth_set_ringparam()

After this, I could run the loop for 100,000 iterations successfully.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the device is down then no packet buffers should be allocated.
We also must not touch its registers as it may be powered off.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We must only ever stop TX queues when they are full or the net device
is not 'ready' so far as the net core, and specifically the watchdog,
is concerned.  Otherwise, the watchdog may fire *immediately* if no
packets have been added to the queue in the last 5 seconds.

What's more, sh_eth_tx_timeout() will likely crash if called while
we're resizing the TX ring.

I could easily trigger this by running the loop:

   while ethtool -G eth0 rx 128 && ethtool -G eth0 rx 64; do echo -n .; done
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If an skb to be transmitted is shorter than the minimum Ethernet frame
length, we currently set the DMA descriptor length to the minimum but
do not add zero-padding.  This could result in leaking sensitive
data.  We also pass different lengths to dma_map_single() and
dma_unmap_single().

Use skb_padto() to pad properly, before calling dma_map_single().
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver connects and disconnects the PHY device whenever the
net device is brought up and down.  The ethtool get_settings,
set_settings and nway_reset operations will dereference a null
or dangling pointer if called while it is down.

I think it would be preferable to keep the PHY connected, but there
may be good reasons not to.

As an immediate fix for this bug:
- Set the phydev pointer to NULL after disconnecting the PHY
- Change those three operations to return -ENODEV while the PHY is
  not connected
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently net_device_ops::set_rx_mode is only implemented for
chips with a TSU (multiple address table).  However we do need
to turn the PRM (promiscuous) flag on and off for other chips.

- Remove the unlikely() from the TSU functions that we may safely
  call for chips without a TSU
- Make setting of the MCT flag conditional on the tsu capability flag
- Rename sh_eth_set_multicast_list() to sh_eth_set_rx_mode() and plumb
  it into both net_device_ops structures
- Remove the previously-unreachable branch in sh_eth_rx_mode() that
  would otherwise reset the flags to defaults for non-TSU chips
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit b284fbe3 ("sh_eth: Fix access to TRSCER register") wanted
to add a .trscer_err_mask value to the R-Car Gen2 family-specific data
structure (r8a779x_data), but it was accidentally added to the
SH7724-specific data structure (sh7724_data).

Presumably this happened due to a patch conflict with commit
d407bc02 ("sh-eth: Set fdr_value of R-Car SoCs"), which added
another field at the same position.

Move the field setting to fix this.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Fixes: b284fbe3 ("sh_eth: Fix access to TRSCER register")
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TRSCER register is configured differently by SoCs. TRSCER of R-Car Gen2 is
RINT8 bit only valid, other bits are reserved bits. This removes access to
TRSCER register reserve bit by adding variable trscer_err_mask to
sh_eth_cpu_data structure, set the register information to each SoCs.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

FDR register of R-Car set in fdr_value can have the original settings.
This sets the value that is suitable for each SoCs to fdr_value of R8A777x
and R8A779x.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

PTR_ALIGN macro after skb_reserve is redundant, because skb_reserve
function adjusts the alignment of skb->data.
Signed-off-by: NMitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both of 'boguscnt' and 'quota' have nearly meaning as the condition of
the reception loop.
In order to cut down redundant processing, this patch changes excess
judgement.
Signed-off-by: NMitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This resolves the following bug which can be reproduced by building the
kernel with CONFIG_DEBUG_ATOMIC_SLEEP=y and reading network statistics
while the network interface is down.

e.g.:

ifconfig eth0 down
cat /sys/class/net/eth0/statistics/tx_errors

----
[ 1238.161349] BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:952
[ 1238.188279] in_atomic(): 1, irqs_disabled(): 0, pid: 1388, name: cat
[ 1238.207425] CPU: 0 PID: 1388 Comm: cat Not tainted 3.10.31-ltsi-00046-gefa0b46 #1087
[ 1238.230737] Backtrace:
[ 1238.238123] [<c0012e64>] (dump_backtrace+0x0/0x10c) from [<c0013000>] (show_stack+0x18/0x1c)
[ 1238.263499]  r6:000003b8 r5:c06160c0 r4:c0669e00 r3:00404000
[ 1238.280583] [<c0012fe8>] (show_stack+0x0/0x1c) from [<c04515a4>] (dump_stack+0x20/0x28)
[ 1238.304631] [<c0451584>] (dump_stack+0x0/0x28) from [<c004970c>] (__might_sleep+0xf8/0x118)
[ 1238.329734] [<c0049614>] (__might_sleep+0x0/0x118) from [<c02465ac>] (__pm_runtime_resume+0x38/0x90)
[ 1238.357170]  r7:d616f000 r6:c049c458 r5:00000004 r4:d6a17210
[ 1238.374251] [<c0246574>] (__pm_runtime_resume+0x0/0x90) from [<c029b1c4>] (sh_eth_get_stats+0x44/0x280)
[ 1238.402468]  r7:d616f000 r6:c049c458 r5:d5c21000 r4:d5c21000
[ 1238.419552] [<c029b180>] (sh_eth_get_stats+0x0/0x280) from [<c03ae39c>] (dev_get_stats+0x54/0x88)
[ 1238.446204]  r5:d5c21000 r4:d5ed7e08
[ 1238.456980] [<c03ae348>] (dev_get_stats+0x0/0x88) from [<c03c677c>] (netstat_show.isra.15+0x54/0x9c)
[ 1238.484413]  r6:d5c21000 r5:d5c21238 r4:00000028 r3:00000001
[ 1238.501495] [<c03c6728>] (netstat_show.isra.15+0x0/0x9c) from [<c03c69b8>] (show_tx_errors+0x18/0x1c)
[ 1238.529196]  r7:d5f945d8 r6:d5f945c0 r5:c049716c r4:c0650e7c
[ 1238.546279] [<c03c69a0>] (show_tx_errors+0x0/0x1c) from [<c023963c>] (dev_attr_show+0x24/0x50)
[ 1238.572157] [<c0239618>] (dev_attr_show+0x0/0x50) from [<c010c148>] (sysfs_read_file+0xb0/0x140)
[ 1238.598554]  r5:c049716c r4:d5c21240
[ 1238.609326] [<c010c098>] (sysfs_read_file+0x0/0x140) from [<c00b9ee4>] (vfs_read+0xb0/0x13c)
[ 1238.634679] [<c00b9e34>] (vfs_read+0x0/0x13c) from [<c00ba0ac>] (SyS_read+0x44/0x74)
[ 1238.657944]  r8:bef45bf0 r7:00000000 r6:d6ac0600 r5:00000000 r4:00000000
[ 1238.678172] [<c00ba068>] (SyS_read+0x0/0x74) from [<c000eec0>] (ret_fast_syscall+0x0/0x30)
----
Signed-off-by: NMitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the current driver, allocation size of skb does not care the alignment
adjust after allocation.
And also, in the current implementation, buffer alignment method by
sh_eth_set_receive_align function has a bug that this function displace
buffer start address forcedly when the alignment is corrected.
In the result, tail of the skb will exceed allocated area and kernel panic
will be occurred.
This patch fix this issue.
Signed-off-by: NMitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The device tree probing for R-Car M2N (r8a7793) is added.
Signed-off-by: NHisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using RMMI mode, it is necessary to change in probe.
Signed-off-by: NHisashi Nakamura <hisashi.nakamura.ak@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

devm_ioremap_resource checks platform_get_resource() return value.
We can remove the duplicate check here.
Signed-off-by: NVarka Bhadram <varkab@cdac.in>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHisashi Nakamura <hisashi.nakamura.ak@renesas.com>
[uli: added bindings documentation]
Signed-off-by: NUlrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since consume_skb() (and hence dev_kfree_skb() macro) checks the passed pointer
for NULL, there's no need to check for NULL before invoking dev_kfree_skb().
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes an issue that we cannot use nfs rootfs correctly
on r8a7790 when the command below runs on a host PC.

 $ sudo ping -f -l 8 $BOARD_IP_ADDR

Since the driver sets the RACT to 1 in the first while loop of
sh_eth_rx(), the controller accepts a next frame into the next RX
descriptor during the while loop. But, in the first while loop
doesn't allocate a next skb. So, this patch removes the RACT setting
in the first while loop of sh_eth_rx().
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes the packet "exceeded" condition in sh_eth_rx() when
RACT in an RX descriptor is not set and the "quota" is 0.
Otherwise, kernel panic happens because the "&n->poll_list" is deleted
twice in sh_eth_poll() which calls napi_complete() and net_rx_action().
Signed-off-by: NKouei Abe <kouei.abe.cp@renesas.com>
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 4a55530f (net: sh_eth: modify the definitions of register) managed
to leave out the E-DMAC register entries in sh_eth_offset_fast_sh3_sh2[], thus
totally breaking SH7619/771x support.  Add the missing entries using  the data
from before that commit.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The current behaviour of the sh_eth driver is not to use the RNC bit
for the receive ring. This means that every packet recieved is not only
generating an IRQ but it also stops the receive ring DMA as well until
the driver re-enables it after unloading the packet.

This means that a number of the following errors are generated due to
the receive packet FIFO overflowing due to nowhere to put packets:

	net eth0: Receive FIFO Overflow

Since feedback from Yoshihiro Shimoda shows that every supported LSI
for this driver should have the bit enabled it seems the best way is
to remove the RMCR default value from the per-system data and just
write it when initialising the RMCR value. This is discussed in
the message (http://www.spinics.net/lists/netdev/msg284912.html).

I have tested the RMCR_RNC configuration with NFS root filesystem and
the driver has not failed yet.  There are further test reports from
Sergei Shtylov and others for both the R8A7790 and R8A7791.

There is also feedback fron Cao Minh Hiep[1] which reports the
same issue in (http://comments.gmane.org/gmane.linux.network/316285)
showing this fixes issues with losing UDP datagrams under iperf.
Tested-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Acked-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When I was converting the driver to the managed device API, only devm_kzalloc()
was available for memory allocation, so I had to use it, despite zeroing out the
PHY IRQ array right before initializing all  its entries to PHY_POLL was quite
stupid.   Now that devm_kmalloc_array() has become available, we can avoid the
needless zeroing out...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net: get rid of SET_ETHTOOL_OPS

Dave Miller mentioned he'd like to see SET_ETHTOOL_OPS gone.
This does that.

Mostly done via coccinelle script:
@@
struct ethtool_ops *ops;
struct net_device *dev;
@@
-       SET_ETHTOOL_OPS(dev, ops);
+       dev->ethtool_ops = ops;

Compile tested only, but I'd seriously wonder if this broke anything.
Suggested-by: NDave Miller <davem@davemloft.net>
Signed-off-by: NWilfried Klaebe <w-lkml@lebenslange-mailadresse.de>
Acked-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The pm_rumtime work queue is causing the device to be suspended during
initialisation, thus the initialisation may not be able to access registers
properly. As the code is called from a work queue, it is possible that this
is not seen from certain configurations/builds due to the asynchronos
nature of the code.

Another issue has also been found where the network device registration
calls back into the driver thus causing further pm_runtime calls that
also caused issues with the MDIO bus code. This has now been checked
and is the only place the MDIO can be called without the device open.

Use pm_runtime_get_sync() and pm_runtime_put() to ensure that the
pm system does not suspend it during the probe() call and remove the
now unnecessary pm_runtime_resume() call. Also add a call in the error
path to call pm_runtime_disable().

This fixes the external abort that can cause /sbin/init or other such
init processed to die.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Tested-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

"goto" is well accepted for error paths in the kernel but should not be
used unnecessarily. Return the correct value directly instead of using a
goto when possible.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Network API functions that rely on the MDIO bus can be called as soon as
the driver calls register_netdev(). Register the MDIO bus before the
network device to avoid race conditions.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The network device passed to the sh_mdio_init and sh_mdio_release
functions is only used to access the sh_eth_private instance. Pass it
directly to those functions.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The MDIO bus parent is set to the network device. Beside not reflecting
the hardware topology, this prevents registering the MDIO bus before
initializing the network device. Fix it by setting the MDIO bus parent
to the platform device.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Memory allocated for the MDIO bus with the devm_kzalloc() API is
associated with the network device. While this will cause memory to be
freed at the right time, it doesn't allow allocating memory before the
network device is initialized.

Replace the network device with the parent platform device for memory
allocation to remove that dependency. This also improves consistency
with the other devm_* calls in the driver that all use the platform
device.
Signed-off-by: NLaurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that we call netdev_*() under netif_msg_*() checks, we can fold these into
netif_*() macro invocations.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert dev_*(&ndev->dev, ...) to netdev_*(ndev, ...) calls since they are a bit
shorter and at the same time give more information on a device.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert pr_*() to netdev_*() calls as the latter provide info on a device.
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Exit the driver's probe() method when the register layout is unknown as the
driver would cause kernel oops in this case anyway.

While at it, move the corresponding error message printout and convert it from
pr_err() to dev_err().
Suggested-by: NJoe Perches <joe@perches.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the sh_eth device is registered using OF, then the driver
should call of_mdiobus_register() to register the PHYs described
in the devicetree and then use of_phy_connect() to connect the
PHYs to the device.

This ensures that any PHYs registered in the device tree are
appropriately connected to the parent devices nodes so that
the PHY drivers can access their OF properties.
Signed-off-by: NBen Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support of the device tree probing for the Renesas SH-Mobile SoCs
documenting the device tree binding as necessary.

This work is loosely based on the original patch by Nobuhiro Iwamatsu
<nobuhiro.iwamatsu.yj@renesas.com>.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver #define's and uses ETHERSMALL macro for the minimum Ethernet frame
size for which we have a standard macro ETH_ZLEN.  Use the latter  instead of
the home-grown one.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>