Since commit 1fa59bda ("ARM: shmobile: Remove legacy board code
for Armadillo-800 EVA"), r8a7740 is only supported in generic DT-only
ARM multi-platform builds.  The driver doesn't need to match platform
devices by name anymore, hence remove the corresponding
platform_device_id entry.

Protect r8a7740_data by #ifdef CONFIG_OF as it's now referenced on DT
platforms only. Move it to a more logical position, in front of the
r8a777x support, so we can have a single #ifdef covering all r7s* and
r8a* support soon. This requires moving a few helper functions, too.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit a483dcbf ("ARM: shmobile: lager: Remove legacy
board support"), R-Car Gen2 SoCs are only supported in generic DT-only
ARM multi-platform builds.  The driver doesn't need to match platform
devices by name anymore, hence remove the corresponding
platform_device_id entry.

Protect r8a779x_data by #ifdef CONFIG_OF as it's now referenced on DT
platforms only.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 05104c26 ("ARM: shmobile: r7s72100: genmai: Remove
legacy board file"), r7s72100 is only supported in generic DT-only ARM
multi-platform builds.  The driver doesn't need to match platform
devices by name anymore, hence remove the corresponding
platform_device_id entry.

Protect r7s72100_data by #ifdef CONFIG_OF as it's now referenced on DT
platforms only. Move it to a more logical position, in front of the
r8a777x support, so we can have a single #ifdef covering all r7s* and
r8a* support soon. This requires moving a helper function, too.
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The GTI.TIV may be set to 2GHz^2 / rate, where rate is
that of the clock of the device. Rather than assuming a
rate of 130MHz use the actual rate of the clock.

The motivation for this is to use the correct rate on
the r8a7795/Salvator-X which is advertised as 133MHz but
may differ depending on the extal present on the Salvator-X.
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver does not handle the AVB-DMAC Receive FIFO Warning interrupt
now, so the interrupt should not be enabled.
Signed-off-by: NMasaru Nagai <masaru.nagai.vx@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When RX/TX interrupt for Network Control queue and Best Effort queue
is issued at the same time, the interrupt mask of Network Control
queue will be reset when the mask of Best Effort queue is set.
This patch fixes this problem.
Signed-off-by: NMasaru Nagai <masaru.nagai.vx@renesas.com>
Signed-off-by: NYoshihiro Kaneko <ykaneko0929@gmail.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Acked-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While the ring allocation is done by a single function, sh_eth_ring_init(),
the ring deallocation was split into two functions (almost always called
one after the other) for no good reason. Merge  sh_eth_free_dma_buffer()
into sh_eth_ring_free() which allows us  to save space not only on the
direct calls  of the former function but also on the sh_eth_ring_init()'s
simplified error path...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The 'ret' local variable in sh_eth_ring_init() serves no useful purpose as
the only  values it gets assigned are 0 and -ENOMEM both of which could be
returned directly...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit  7d7355f5 ("sh_eth: Ensure proper ordering of descriptor active
bit write/read") did the right thing  but used too "heavy" barriers while
there were already "lighter" DMA barriers exactly  for this case...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The correct name of the RX descriptor 0 bit 30 is RDLE (receive descriptor
list end),  not  RDEL.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This corrects what appear to be typos, making the code consistent with
itself, and allowing meaningful prefixes to be displayed with the errors in
question.

Before:
 (null): failed to initialize MDIO
 (null): Cannot allocate desc base address table (size 176 bytes)

After:
ravb e6800000.ethernet: failed to initialize MDIO
ravb e6800000.ethernet: Cannot allocate desc base address table (size 176 bytes)
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Iff the first dma_alloc_coherent()  call fails in sh_eth_ring_init(), the
following  is printed to the kernel console:

WARNING: CPU: 0 PID: 1 at drivers/base/dma-mapping.c:334 dma_common_free_remap+0x48/0x6c()
trying to free invalid coherent area:   (null)
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.3.0-rc7-dirty #969
Hardware name: Generic R8A7791 (Flattened Device Tree)
Backtrace:
[<c0013820>] (dump_backtrace) from [<c00139bc>] (show_stack+0x18/0x1c)
 r6:c0662856 r5:00000009 r4:00000000 r3:00204140
[<c00139a4>] (show_stack) from [<c0227510>] (dump_stack+0x74/0x90)
[<c022749c>] (dump_stack) from [<c0026ef4>] (warn_slowpath_common+0x8c/0xb8)
 r4:ee84dce0 r3:c0712774
[<c0026e68>] (warn_slowpath_common) from [<c0026fc4>] (warn_slowpath_fmt+0x38/0x40)
 r8:ee7f8000 r7:c0734520 r6:00001000 r5:20000008 r4:00000000
[<c0026f90>] (warn_slowpath_fmt) from [<c02df404>] (dma_common_free_remap+0x48/0x6c)
 r3:00000000 r2:c0662871
[<c02df3bc>] (dma_common_free_remap) from [<c001b9fc>] (__arm_dma_free+0xb8/0xd4)
r6:00000001 r5:00000000 r4:00001000 r3:ee8c5584
[<c001b944>] (__arm_dma_free) from [<c001ba68>] (arm_dma_free+0x24/0x2c)
 r10:0000016b r8:00000000 r7:ee9bc830 r6:00000000 r5:00000400 r4:ee9bc800
[<c001ba44>] (arm_dma_free) from [<c032ebf0>] (sh_eth_ring_init+0x110/0x138)
[<c032eae0>] (sh_eth_ring_init) from [<c033179c>] (sh_eth_open+0x94/0x1f4)
 r6:00000000 r5:ee9bcd18 r4:ee9bc800
[<c0331708>] (sh_eth_open) from [<c041bf7c>] (__dev_open+0x84/0x104)
 r6:c0565c50 r5:00000000 r4:ee9bc800
[<c041bef8>] (__dev_open) from [<c041c208>] (__dev_change_flags+0x94/0x13c)
 r7:00001002 r6:00000001 r5:00001003 r4:ee9bc800
[<c041c174>] (__dev_change_flags) from [<c041c2e8>] (dev_change_flags+0x20/0x50)
 r7:c072c8a0 r6:00000138 r5:00001002 r4:ee9bc800
[<c041c2c8>] (dev_change_flags) from [<c06e8d4c>] (ip_auto_config+0x174/0xf7c)
 r8:00001002 r7:c072c8a0 r6:c0700040 r5:00000001 r4:ee9bc800 r3:00000101
[<c06e8bd8>] (ip_auto_config) from [<c000a810>] (do_one_initcall+0x100/0x1c8)
 r10:c06f883c r9:00000000 r8:c06e8bd8 r7:c0734000 r6:c070e918 r5:c070e918
 r4:ee083640
[<c000a710>] (do_one_initcall) from [<c06c9ddc>] (kernel_init_freeable+0x11c/0x1ec)
 r10:c06f883c r9:00000000 r8:00000099 r7:c0734000 r6:c070372c r5:c06f8834
 r4:00000007
[<c06c9cc0>] (kernel_init_freeable) from [<c0514d78>] (kernel_init+0x14/0xec)
 r10:00000000 r8:00000000 r7:00000000 r6:00000000 r5:c0514d64 r4:c0734000
[<c0514d64>] (kernel_init) from [<c0010458>] (ret_from_fork+0x14/0x3c)
 r4:00000000 r3:ee84c000

This is because the code jumps to a wrong label and so tries to free yet
unallocated coherent memory.  Fix the *goto* in question.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sh_eth_ring_free()  called in the sh_eth_ring_init()'s error path expects
the arrays pointed  to  by 'sh_eth_private::[rt]x_skbuff' to be initialized
with NULLs but they are allocated with just kmalloc_array() and so are left
filled with random data. Use kcalloc() instead.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The RX buffer size calulation failed to account for the length granularity
(which is now 32 bytes)...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Both  Renesas R-Car and RZ/A1 manuals state that RX buffer  length must be
a multiple of 32 bytes, while the driver  only uses 16 byte granularity...
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch supports the r8a7795 SoC by:
- Using two interrupts
  + One for E-MAC
  + One for everything else
  + Both can be handled by the existing common interrupt handler, which
    affords a simpler update to support the new SoC. In future some
    consideration may be given to implementing multiple interrupt handlers
- Limiting the phy speed to 100Mbit/s for the new SoC;
  at this time it is not clear how this restriction may be lifted
  but I hope it will be possible as more information comes to light
Signed-off-by: NKazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
[horms: reworked]
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch is in preparation for using this driver on arm64 where the
implementation of __dma_alloc_coherent fails if a device parameter is not
provided.
Signed-off-by: NKazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com>
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NMasaru Nagai <masaru.nagai.vx@renesas.com>
[horms: squashed into a single patch]
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver overrides the error returned by platform_get_irq() with -ENODEV
which e.g. precludes the deferred  probing from working. Propagate the real
error code to the driver core instead.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver overrides the error returned by platform_get_irq() with -ENODEV
which e.g. precludes the deferred  probing from working. Propagate the real
error code to the driver core instead.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Renesas Ethernet AVB controller requires that all data are aligned on 4-byte
boundary.  While it's  easily achievable for  the RX  data with  the help of
skb_reserve() (we even align on 128-byte boundary as recommended by the manual),
we  can't  do the same with the TX data, and it always comes  unaligned from
the networking core. Originally we solved it an easy way, copying all packet
to  a  preallocated  aligned buffer; however, it's enough to copy only up to
3 first bytes from each packet, doing the transfer using 2 TX descriptors
instead of just 1. Here's an implementation of the new  TX algorithm that
significantly reduces the driver's memory requirements.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The driver is written as if it can adapt to a low memory situation  allocating
less RX  skbs and TX aligned buffers than the respective RX/TX ring sizes.  In
reality  though  the driver  would malfunction in this case. Stop being overly
smart and just fail in such situation -- this is achieved by moving the memory
allocation from ravb_ring_format() to ravb_ring_init().

We leave dma_map_single() calls in place but make their failure non-fatal
by marking the corresponding RX descriptors  with zero data size which should
prevent DMA to an invalid addresses.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The TCCR.TSRQn bit may get clearead after TCCR gets read, so that TCCR write
would get skipped. We don't need to check this bit before setting.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

First, dma_sync_single_for_cpu() shouldn't have been called in the first place
(it's a streaming DMA API), dma_unmap_single() should have been called instead.
Second, dma_unmap_single() call after handing the buffer to napi_gro_receive()
makes little sense.  Moreover desc->dptr might not be valid at this point.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some of the local variable intializers in the driver turned out to be pointless,
kill them.
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to unlock before returning here.

Fixes: a0d2f206 ('Renesas Ethernet AVB PTP clock driver')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This howto made sense in the 1990s when users had to manually configure
ISA cards with jumpers or vendor utilities, but with the implementation
of PCI it became increasingly less and less relevant, to the point where
it has been well over a decade since I last updated it.  And there is
no value in anyone else taking over updating it either.

However the references to it continue to spread as boiler plate text
from one Kconfig file into the next.  We are not doing end users any
favours by pointing them at this old document, so lets kill it with
fire, once and for all, to hopefully stop any further spread.

No code is changed in this commit, just Kconfig help text.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ethernet AVB device includes the gPTP  timer, so we can implement a PTP clock
driver.  We're doing that in a separate file, with  the main Ethernet driver
calling the PTP driver's [de]initialization and interrupt handler functions.
Unfortunately, the clock seems tightly coupled with the AVB-DMAC, so when that
one leaves the operation mode, we have to unregister the PTP clock... :-(

Based on the original patches by Masaru Nagai.
Signed-off-by: NMasaru Nagai <masaru.nagai.vx@renesas.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ethernet AVB includes an Gigabit Ethernet controller (E-MAC) that is basically
compatible with SuperH Gigabit Ethernet E-MAC.  Ethernet AVB has  a  dedicated
direct memory access controller (AVB-DMAC) that is a new design compared to the
SuperH E-DMAC. The AVB-DMAC is compliant with 3 standards formulated for IEEE
802.1BA: IEEE 802.1AS timing and synchronization protocol, IEEE 802.1Qav real-
time transfer, and the IEEE 802.1Qat stream reservation protocol.

The  driver only supports device tree probing, so the binding document is
included in this patch.

Based on the original patches by Mitsuhiro Kimura.
Signed-off-by: NMitsuhiro Kimura <mitsuhiro.kimura.kc@renesas.com>
Signed-off-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The statistics registers have write-clear behaviour, which means we
will lose any increment between the read and write.  Mitigate this by
only clearing when we read a non-zero value, so we will never falsely
report a total of zero.  This also saves time as we only handle
error statistics here and they won't often be incremented.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are many different sets of registers implemented by the
different versions of this controller, and we can only expect this to
get more complicated in future.  Limit how much ethtool needs to know
by including an explicit bitmap of which registers are included in the
dump, allowing room for future growth in the number of possible
registers.

As I don't have datasheets for all of these, I've only included
registers that are:

- defined in all 5 register type arrays, or
- used by the driver, or
- documented in the datasheet I have

Add one new capability flag so we can tell whether the RTRATE
register is implemented.

Delete the TSU_ADRL0 and TSU_ADR{H,L}31 definitions, as they weren't
used and the address table is already assumed to be contiguous.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently we may silently read/write a register at offset 0.  Change
this to WARN and then ignore the write or read-back all-ones.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Acked-by: NSergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

At least on the R8A7790, RFS8 reflects the RINT8 (multicast) MAC
status flag.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

My previous fix to clear padding of short frames used skb->len as the
DMA length, assuming that skb_padto() extended skb->len to include the
padding.  That isn't the case; we need to use skb_put_padto() instead.

(This wasn't immediately obvious because software padding isn't
actually needed on the R-Car H2.  We could make it conditional on
which chip is being driven, but it's probably not worth the effort.)
Reported-by: N"Violeta Menéndez González" <violeta.menendez@codethink.co.uk>
Fixes: 612a17a54b50 ("sh_eth: Fix padding of short frames on TX")
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit fd9af07c.

The hardware manual states that the frame error and multicast bits are
copied to bits 9:0 of RD0, not bits 25:16.  I've tested that this is
true for RFS1 (CRC error), RFS3 (frame too short), RFS4 (frame too
long) and RFS8 (multicast).

Also adjust a comment to agree with this.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case of RX ring underrun (RDE), we attempt to reset the software
descriptor pointers (dirty_rx and cur_rx) to match where the hardware
will read the next descriptor from, as that might not be the first
dirty descriptor.  This relies on reading RDFAR, but that register
doesn't exist on all supported chips - specifically, not on the R-Car
chips.  This will result in unpredictable behaviour on those chips
after an RDE.

Make this pointer reset conditional and assume that it isn't needed on
the R-Car chips.  This fix also assumes that RDFAR is never exposed at
offset 0 in the memory map - this is currently true, and a subsequent
commit will fix the ambiguity between offset 0 and no-offset in the
register offset maps.

Fixes: 79fba9f5 ("net: sh_eth: fix the rxdesc pointer when rx ...")
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When submitting a DMA descriptor, the active bit must be written last.
When reading a completed DMA descriptor, the active bit must be read
first.

Add memory barriers to ensure that this ordering is maintained.
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 740c7f31 ("sh_eth: Ensure DMA engines are stopped before
freeing buffers") added a call to sh_eth_reset() to the
sh_eth_set_ringparam() and sh_eth_close() paths.

However, setting the software reset bit(s) in the EDMR register resets
the MAC Address Registers to zero. Hence after kexec, the new kernel
doesn't detect a valid MAC address and assigns a random MAC address,
breaking DHCP.

Set the MAC address again after the reset in sh_eth_dev_exit() to fix
this.

Tested on r8a7740/armadillo (GETHER) and r8a7791/koelsch (FAST_RCAR).

Fixes: 740c7f31 ("sh_eth: Ensure DMA engines are stopped before freeing buffers")
Signed-off-by: NGeert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Use the return value of dma_map_single(), rather than calling
  virt_to_page() separately
- Check for mapping failue
- Call dma_unmap_single() rather than dma_sync_single_for_cpu()
Signed-off-by: NBen Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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>