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>

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>

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 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>

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>

The r7s72100 SoC includes a fast ethernet controller.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Acked-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Running 'scripts/checkpatch.pl' on the driver files gives numerous warnings:

- block comments using empty /* line;

- unneeded \ at end of lines;

- message string split across lines;

- use of __attribute__((aligned(n))) instead of __aligned(n) macro;

- use of __attribute__((packed)) instead of __packed macro.

Additionally, running 'scripts/checkpatch.pl --strict' gives more complaints:

- including the paragraph about writing to FSF into the heading comment;

- alignment not matching open paren;

- multiple assignments on one line;

- use of CamelCase names;

- missing {} on one of the *if* arms where another has them;

- spinlock definition without a comment.

While fixing these, also do some more style cleanups:

- remove useless () around expressions;

- add {} around multi-line *if* operator's arm;

- remove space before comma;

- add spaces after /* and before */;

- properly align continuation lines of broken up expressions;

- realign comments to the structure fields.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Declare 'enum RMCR_BIT' containing the single member for the RMCR.RNC bit and
replace bare numbers in the driver by  this mnemonic.
Suggested-by: NDavid Miller <davem@davemloft.net>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that the 'register_type' field of the 'sh_eth' driver's platform data is not
used by the driver anymore, it's time to remove it and  its initializers from
the SH platform code. Also  move *enum* declaring values for this  field from
<linux/sh_eth.h>  to  the  local driver's  header file as they're only needed
by the driver itself  now...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The register layout is a SoC characteristic, so it's wrong that it's stored
in the otherwise board specific platform data. Add 'register_type' field to
'struct sh_eth_cpu_data', initialize it properly for each SoC, and read  it
from this structure instead of the platfrom data from now on...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This register is prsent on the r8a7790 SoC.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

EESR.RFE (receive FIFO overflow) interrupt is enabled by the driver on all SoCs
and sh_eth_error() handles it but it's not present in any initializer/assignment
of the 'eesr_err_check' field of 'struct sh_eth_cpu_data'. This leads to that
interrupt not being handled and cleared, and finally to disabling IRQ and the
driver being non-functional.

Modify DEFAULT_EESR_ERR_CHECK macro and all explicit initializers of the above
mentioned field to contain the EESR.RFE bit. Remove useless backslashes from the
initializers, while at it.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only R8A7740 specific #ifdef hindering  ARM multiplatform build is  left in
sh_eth_rx(): it covers the code shifting Rx buffer descriptor word 0 by 16. Get
rid of the #ifdef by adding 'shift_rd0' field to the  'struct sh_eth_cpu_data',
making the shift dependent on it, and setting it to 1 for the R8A7740 case...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the comment to 'enum TD_STS_BIT', reformat the values, and add a couple of
values missing before (though unused by the driver).
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 'tx_error_check' field of 'struct sh_eth_cpu_data' is write-only, so remove
it along with the DEFAULT_TX_ERROR_CHECK macro.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver hasn't used NAPI so far; implement its support at last...

The patch was tested on Renesas R8A77781 BOCK-W board.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sh_eth_interrupt() uses the same Rx interrupt mask twice to check the interrupt
status register -- #define EESR_RX_CHECK  and use it instead.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver supports some SH and SH-Mobile SOCs. There are SOCs with two or more
Ethernet devices, for these we need to pass IRQF_SHARED to request_irq().  Add
the 'irq_flags' field to the 'struct sh_eth_cpu_data' instead of #ifdef'fery.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
[Sergei: properly aligned request_irq() call continuation line, reworded the
changelog, reworded the subject, changing the prefix.]
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove #ifdef around 'enum EDSR_BIT' and 'enum GECMR_BIT', replacing it with the
comments on which SoCs these registers exist.

SH7757 also has EDSR, so add a comment about it to 'enum EDSR_BIT'.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
[Sergei: folded in the former patch #2, updated the changelog, reworded the
subject, changing the prefix.]
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 'link' field of 'struct sh_eth_private' has type 'enum phy_state' while the
'link' field of 'struct phy_device' is merely *int* (having values 0 and 1) and
the former field gets assigned from the latter. Make the field match, getting
rid of incorrectly used PHY_DOWN value in assignments/comparisons.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver's header file contains initialized register offset tables which (as
any data definitions), of course, have no business being there.  Move them  to
the driver's body, somewhat beautifying the initializers, while at it...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Switch the driver to the managed device API by replacing ioremap() calls with
devm_ioremap_resource() (that will also result in calling request_mem_region()
which the driver forgot to do until now) and k[mz]alloc() with devm_kzalloc() --
this permits to simplify driver's probe()/remove() method cleanup. We can now
remove the ioremap() error messages since the error messages are printed by
 devm_ioremap_resource() itself. We can also remove the 'bitbang' field from
'struct sh_eth_private' as we don't need it anymore in order to free the memory
behind it...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sh_mdio_init() allocates pointer to 'struct bb_info' but only stores it locally,
so that sh_mdio_release() can't free it on driver unload.  Add the pointer to
'struct bb_info' to 'struct sh_eth_private', so that sh_mdio_init() can save
'bitbang' variable for sh_mdio_release() to be able to free it later...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch supports the ethtool's set_ringparam() and get_ringparam().
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes unnecessary members in sh_th_private.
This patch also removes unnecessary definitions in sh_eth.h
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sh_eth_timer() called mod_timer() for itself. So, this patch
removes the function.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ethernet IP of SH7734 and R8A7740 has selecting MII register.
The user needs to change a value according to MII to be used.
This adds the function to change the value of this register.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The R8A7740 has a Gigabit Ethernet MAC. This patch supports it.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SuperH has the "CONFIG_CPU_LITTLE_ENDIAN" and the "__LITTLE_ENDIAN__".
But, other architecture doesn't have them. So, this patch fixes it.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add define of SH7734 register and sh_eth_reset_hw_crc function.

V3: Rebase net/HEAD.
V2: Do not split line of #if defined.
Signed-off-by: NNobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some controllers have TSU. It can register one VLAN tag, and it can
filter other VLAN tag by hardware.
If vlan_rx_add_vid() is called twice or more, the driver will disable
the filtering.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some controllers have TSU. It can filter multicast by hardware.
This patch supports it.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No need to maintain a parallel net_device_stats structure in
sh_eth_private, since we have a generic one in netdev

Fix two dma_map_single() incorrect parameters, passing skb->tail instead
of skb->data. Seems that there is no corresponding dmap_unmap_single()
calls for the moment in this driver.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When this GETHER controller received a large frame (about 1800 bytes
or more), skb_over_panic() happened. This is because the previous
driver set the RFLR to 0x1000 (4096 bytes) and the skb allocate size
is smaller than 4096 bytes. So, the controller accepted such a frame.

The controller can discard a large frame by the RFLR setting.
So, the patch modifies the value of RFLR to mtu + ETH_HLEN +
VLAN_HLEN + ETH_FCS_LEN.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch also changes writel/readl to iowrite32/ioread32.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move the Renesas driver into drivers/net/ethernet/renesas/ and make
the necessary Kconfig and Makefile changes.

CC: Yoshihiro Shimoda <yoshihiro.shirmoda.uh@renesas.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

The previous code had hardcoded the PHY_INTERFACE_MODE_MII of phy_connect.
So some Gigabit PHYs will not behave correctly.
The patch adds the phy_interface in sh_eth_plat_data, so we can select
the phy interface.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The SH7763 has GETHER. So the specification of some registers differs than
other CPUs. This patch removes almost #ifdef of CONFIG_CPU_SUBTYPE_SH7763.
Then we are able to add other CPU's GETHER easily.
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>