Hopefully my understanding of how the hardware works is correct,
as the documentation isn't completely clear. So far I have seen
no obvious issue. Pause seem to also work with NC-SI.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Directly access the fields when needed. The accessors add clutter
not clarity and in some cases cause unnecessary read-modify-write
type access on the slow (uncached) descriptor memory.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Directly access the fields when needed. The accessors add clutter
not clarity and in some cases cause unnecessary read-modify-write
type access on the slow (uncached) descriptor memory.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
First, don't look at the interrupt status in the poll loop
to decide what to poll. It's wrong. If we have run out of
budget, we may still have RX packets to unqueue but no more
RX interrupt pending.
So instead move the code looking at the interrupt status
into the interrupt handler where it belongs. That avoids a slow
MMIO read in the NAPI fast path. We keep the abnormal interrupts
enabled while NAPI is scheduled.
While at it, actually do something useful in the "error" cases:
On AHB bus error, trigger the new reset task, that's about all
we can do. On RX packet fifo or descriptor overflows, we need
to restart the MAC after having freed things up. So set a flag
that NAPI will see and use to perform that restart after
harvesting the RX ring.
Finally, we shouldn't complete NAPI if there are still outgoing
packets that will need harvesting. Waiting for more interrupts
is less efficient than letting NAPI run a while longer while
the queue drains.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The PHYSTS_CHG (the ftgmac100's PHY IRQ) is telling the system to go
look at the PHY registers for a link status change.
The interrupt was causing issues on Aspeed SoC where some board designs
had an active high configuration, some active low, and in some cases
repurposed for other functions. When misconfigured Linux would chew 100%
of CPU cycles servicing interrupts:
[ 20.280000] ftgmac100 1e660000.ethernet eth0: [ISR] = 0x200: PHYSTS_CHG
[ 20.280000] ftgmac100 1e660000.ethernet eth0: [ISR] = 0x200: PHYSTS_CHG
[ 20.280000] ftgmac100 1e660000.ethernet eth0: [ISR] = 0x200: PHYSTS_CHG
[ 20.300000] ftgmac100 1e660000.ethernet eth0: [ISR] = 0x200: PHYSTS_CHG
While in the ftgmac100 IP can be configured for high, low and edge
sensitivity the current driver always polls the PHY, so we chose to mask
out the interrupt.
See https://patchwork.ozlabs.org/patch/672099/ for more discussion.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The Aspeed SoCs have a new MDIO interface as an option in the G4 and G5
SoCs. The old one is still available, so select it in order to remain
compatible with the ftgmac100 driver.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
These bits are #defined at a fixed location. In order to support future
hardware that has chosen to move these bits around move the bits into a
member of the struct ftgmac100.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the Faraday driver into drivers/net/ethernet/faraday/ and
make the necessary Kconfig and Makefile changes.
CC: "Po-Yu Chuang" <ratbert@faraday-tech.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Po-Yu Chuang <ratbert@faraday-tech.com>
Benjamin Herrenschmidt