This flushes out the write to the system before anything continues.
The mips74k guide, chapter 3.3.3 (write gathering) notes that writes
can be buffered in FIFOs - even uncached ones - so we can't guarantee
the device has felt its effects. Now, since we're all lazy driver
authors and don't pepper read/write barriers everywhere, fake it here.
tested:
* mips74k - QCA9558 SoC (AP135 reference board)
This should make it easier to track down interrupt storms from arge.
Tested:
* AP135 (QCA955x) SoC - defaults to ARGE_DEBUG enabled
* Carambola2 (AR9331 SoC) - defaults to ARGE_DEBUG disabled
The early ethernet MACs (I think AR71xx and AR913x) require that both
TX and RX require 4-byte alignment for all packets.
The later MACs have started relaxing the requirements.
For now, the 1-byte TX and 1-byte RX alignment requirements are only for
the QCA955x SoCs. I'll add in the relaxed requirements as I review the
datasheets and do testing.
* Add a hardware flags field and 1-byte / 4-byte TX/RX alignment.
* .. defaulting to 4-byte TX and 4-byte RX alignment.
* Only enforce the TX alignment fixup if the hardware requires a 4-byte
TX alignment. This avoids a call to m_defrag().
* Add counters for various situations for further debugging.
* Set the 1-byte and 4-byte busdma alignment requirement when
the tag is created.
This improves the straight bridging performance from 130mbit/sec
to 180mbit/sec, purely by removing the need for TX path bounce buffers.
The main performance issue is the RX alignment requirement and any RX
bounce buffering that's occuring. (In a local test, removing the RX
fixup path and just aligning buffers raises the performance to above
400mbit/sec.
In theory it's a no-op for SoCs before the QCA955x.
Tested:
* QCA9558 SoC in AP135 board, using software bridging between arge0/arge1.
shifts into the sign bit. Instead use (1U << 31) which gets the
expected result.
This fix is not ideal as it assumes a 32 bit int, but does fix the issue
for most cases.
A similar change was made in OpenBSD.
Discussed with: -arch, rdivacky
Reviewed by: cperciva
The MDIO bus frequency is configured as a divisor off of the MDIO bus
reference clock. For the AR9344 and later, the MDIO bus frequency can
be faster than normal (ie, up to 100MHz) and thus a static divisor may
not be very applicable.
So, for those boards that may require an actual frequency to be selected
regardless of what crazy stuff the vendor throws in uboot, one can now
set the MDIO bus frequency. It uses the MDIO frequency and the target
frequency to choose a divisor that doesn't exceed the target frequency.
By default it will choose:
* DIV_28 on everything; except
* DIV_58 on the AR9344 to be conservative.
Whilst I'm here, add some comments about the defaults being not quite
right. For the other internal switch devices (like the AR933x, AR724x)
the divisor can be higher - it's internal and the reference MDIO clock
is much lower than 100MHz.
The divisor tables and loop code is inspired from Linux/OpenWRT. It's very
simple; I didn't feel that reimplementing it would yield a substantially
different solution.
Tested:
* AR9331 (mips24k)
* AR9344 (mips74k)
Obtained from: Linux/OpenWRT
Without correct barriers, this code just plain doesn't work on the
mips74k cores (specifically the AR9344.)
In particular, the MDIO register accesses need this barriering or MII bus
access results in out-of-order garbage.
Tested:
* AR9344 (mips74k)
* AR9331 (mips24k)
This is only done if the ARGE_MDIO option is included.
* Shuffle the arge MDIO bus into a separate device, that needs to be
probed early (use hint.argemdio.X.order=0)
* hint.arge.X.mdio now specifies which miiproxy to rendezvous with.
* Call MAC/MDIO bus init during MDIO attach, not arge attach.
This is done regardless:
* Shift the arge MAC and MDIO bus reset code into separate functions
and call it early during MDIO bus attach. It's required for
correct MDIO bus IO to occur on AR71xx/AR91xx devices.
* Remove the AR71xx/AR91xx centric assumption that there's only one
MDIO bus. The initial code mapped miibus0(arge0) and miibus1(arge1)
MII register operations to the MII0 (arge0) register space. The
AR724x (and later, upcoming chipsets) have two MDIO busses and
the second is very much in use.
TODO:
* since the multiphy behaviour has changed (where now a phymask of >1
PHY will still be enumerated), multiphy setups may be quite wrong.
I'll go and fix these so they still have a chance of working, at least.
until the switch PHY support appears in -HEAD.
Submitted by: Stefan Bethke <stb@lassitu.de>
fixed-state media with parameters set via hints
and configure MAC accordingly to these parameters.
All the underlying PHY magic is done by boot manager
on startup. At the moment there is no proper way
to make active and control all PHYs simultaneously
from one MII bus and there is no way to associate
incoming/outgoing packet with specific PHY.
