linux-stable.git/drivers, branch v4.14.59

can: m_can.c: fix setup of CCCR register: clear CCCR NISO bit before checking can.ctrlmode

2018-07-28T05:55:45+00:00

commit 393753b217f05474e714aea36c37501546ed1202 upstream.

Inside m_can_chip_config(), when setting up the new value of the CCCR,
the CCCR_NISO bit is not cleared like the others, CCCR_TEST, CCCR_MON,
CCCR_BRSE and CCCR_FDOE, before checking the can.ctrlmode bits for
CAN_CTRLMODE_FD_NON_ISO.

This way once the controller was configured for CAN_CTRLMODE_FD_NON_ISO,
this mode could never be cleared again.

This fix is only relevant for controllers with version 3.1.x or 3.2.x.
Older versions do not support NISO.

Signed-off-by: Roman Fietze 
Cc: linux-stable 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: peak_canfd: fix firmware < v3.3.0: limit allocation to 32-bit DMA addr only

2018-07-28T05:55:45+00:00

commit 5d4c94ed9f564224d7b37dbee13f7c5d4a8a01ac upstream.

The DMA logic in firmwares < v3.3.0 embedded in the PCAN-PCIe FD cards
family is not capable of handling a mix of 32-bit and 64-bit logical
addresses. If the board is equipped with 2 or 4 CAN ports, then such a
situation might lead to a PCIe Bus Error "Malformed TLP" packet
as well as "irq xx: nobody cared" issue.

This patch adds a workaround that requests only 32-bit DMA addresses
when these might be allocated outside of the 4 GB area.

This issue has been fixed in firmware v3.3.0 and next.

Signed-off-by: Stephane Grosjean 
Cc: linux-stable 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix RX overflow interrupt not being enabled

2018-07-28T05:55:45+00:00

commit 83997997252f5d3fc7f04abc24a89600c2b504ab upstream.

RX overflow interrupt (RXOFLW) is disabled even though xcan_interrupt()
processes it. This means that an RX overflow interrupt will only be
processed when another interrupt gets asserted (e.g. for RX/TX).

Fix that by enabling the RXOFLW interrupt.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: Michal Simek 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix incorrect clear of non-processed interrupts

2018-07-28T05:55:45+00:00

commit 2f4f0f338cf453bfcdbcf089e177c16f35f023c8 upstream.

xcan_interrupt() clears ERROR|RXOFLV|BSOFF|ARBLST interrupts if any of
them is asserted. This does not take into account that some of them
could have been asserted between interrupt status read and interrupt
clear, therefore clearing them without handling them.

Fix the code to only clear those interrupts that it knows are asserted
and therefore going to be processed in xcan_err_interrupt().

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: Michal Simek 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: keep only 1-2 frames in TX FIFO to fix TX accounting

2018-07-28T05:55:45+00:00

commit 620050d9c2be15c47017ba95efe59e0832e99a56 upstream.

The xilinx_can driver assumes that the TXOK interrupt only clears after
it has been acknowledged as many times as there have been successfully
sent frames.

However, the documentation does not mention such behavior, instead
saying just that the interrupt is cleared when the clear bit is set.

Similarly, testing seems to also suggest that it is immediately cleared
regardless of the amount of frames having been sent. Performing some
heavy TX load and then going back to idle has the tx_head drifting
further away from tx_tail over time, steadily reducing the amount of
frames the driver keeps in the TX FIFO (but not to zero, as the TXOK
interrupt always frees up space for 1 frame from the driver's
perspective, so frames continue to be sent) and delaying the local echo
frames.

The TX FIFO tracking is also otherwise buggy as it does not account for
TX FIFO being cleared after software resets, causing
  BUG!, TX FIFO full when queue awake!
messages to be output.

There does not seem to be any way to accurately track the state of the
TX FIFO for local echo support while using the full TX FIFO.

The Zynq version of the HW (but not the soft-AXI version) has watermark
programming support and with it an additional TX-FIFO-empty interrupt
bit.

Modify the driver to only put 1 frame into TX FIFO at a time on soft-AXI
and 2 frames at a time on Zynq. On Zynq the TXFEMP interrupt bit is used
to detect whether 1 or 2 frames have been sent at interrupt processing
time.

Tested with the integrated CAN on Zynq-7000 SoC. The 1-frame-FIFO mode
was also tested.

An alternative way to solve this would be to drop local echo support but
keep using the full TX FIFO.

v2: Add FIFO space check before TX queue wake with locking to
synchronize with queue stop. This avoids waking the queue when xmit()
had just filled it.

v3: Keep local echo support and reduce the amount of frames in FIFO
instead as suggested by Marc Kleine-Budde.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix device dropping off bus on RX overrun

2018-07-28T05:55:45+00:00

commit 2574fe54515ed3487405de329e4e9f13d7098c10 upstream.

The xilinx_can driver performs a software reset when an RX overrun is
detected. This causes the device to enter Configuration mode where no
messages are received or transmitted.

The documentation does not mention any need to perform a reset on an RX
overrun, and testing by inducing an RX overflow also indicated that the
device continues to work just fine without a reset.

Remove the software reset.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix recovery from error states not being propagated

2018-07-28T05:55:44+00:00

commit 877e0b75947e2c7acf5624331bb17ceb093c98ae upstream.

The xilinx_can driver contains no mechanism for propagating recovery
from CAN_STATE_ERROR_WARNING and CAN_STATE_ERROR_PASSIVE.

Add such a mechanism by factoring the handling of
XCAN_STATE_ERROR_PASSIVE and XCAN_STATE_ERROR_WARNING out of
xcan_err_interrupt and checking for recovery after RX and TX if the
interface is in one of those states.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix power management handling

2018-07-28T05:55:44+00:00

commit 8ebd83bdb027f29870d96649dba18b91581ea829 upstream.

There are several issues with the suspend/resume handling code of the
driver:

- The device is attached and detached in the runtime_suspend() and
  runtime_resume() callbacks if the interface is running. However,
  during xcan_chip_start() the interface is considered running,
  causing the resume handler to incorrectly call netif_start_queue()
  at the beginning of xcan_chip_start(), and on xcan_chip_start() error
  return the suspend handler detaches the device leaving the user
  unable to bring-up the device anymore.

- The device is not brought properly up on system resume. A reset is
  done and the code tries to determine the bus state after that.
  However, after reset the device is always in Configuration mode
  (down), so the state checking code does not make sense and
  communication will also not work.

- The suspend callback tries to set the device to sleep mode (low-power
  mode which monitors the bus and brings the device back to normal mode
  on activity), but then immediately disables the clocks (possibly
  before the device reaches the sleep mode), which does not make sense
  to me. If a clean shutdown is wanted before disabling clocks, we can
  just bring it down completely instead of only sleep mode.

Reorganize the PM code so that only the clock logic remains in the
runtime PM callbacks and the system PM callbacks contain the device
bring-up/down logic. This makes calling the runtime PM callbacks during
e.g. xcan_chip_start() safe.

The system PM callbacks now simply call common code to start/stop the
HW if the interface was running, replacing the broken code from before.

xcan_chip_stop() is updated to use the common reset code so that it will
wait for the reset to complete. Reset also disables all interrupts so do
not do that separately.

Also, the device_may_wakeup() checks are removed as the driver does not
have wakeup support.

Tested on Zynq-7000 integrated CAN.

Signed-off-by: Anssi Hannula 
Cc: Michal Simek 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

can: xilinx_can: fix RX loop if RXNEMP is asserted without RXOK

2018-07-28T05:55:44+00:00

commit 32852c561bffd613d4ed7ec464b1e03e1b7b6c5c upstream.

If the device gets into a state where RXNEMP (RX FIFO not empty)
interrupt is asserted without RXOK (new frame received successfully)
interrupt being asserted, xcan_rx_poll() will continue to try to clear
RXNEMP without actually reading frames from RX FIFO. If the RX FIFO is
not empty, the interrupt will not be cleared and napi_schedule() will
just be called again.

This situation can occur when:

(a) xcan_rx() returns without reading RX FIFO due to an error condition.
The code tries to clear both RXOK and RXNEMP but RXNEMP will not clear
due to a frame still being in the FIFO. The frame will never be read
from the FIFO as RXOK is no longer set.

(b) A frame is received between xcan_rx_poll() reading interrupt status
and clearing RXOK. RXOK will be cleared, but RXNEMP will again remain
set as the new message is still in the FIFO.

I'm able to trigger case (b) by flooding the bus with frames under load.

There does not seem to be any benefit in using both RXNEMP and RXOK in
the way the driver does, and the polling example in the reference manual
(UG585 v1.10 18.3.7 Read Messages from RxFIFO) also says that either
RXOK or RXNEMP can be used for detecting incoming messages.

Fix the issue and simplify the RX processing by only using RXNEMP
without RXOK.

Tested with the integrated CAN on Zynq-7000 SoC.

Fixes: b1201e44f50b ("can: xilinx CAN controller support")
Signed-off-by: Anssi Hannula 
Cc: 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Greg Kroah-Hartman

driver core: Partially revert "driver core: correct device's shutdown order"

2018-07-28T05:55:44+00:00

commit 722e5f2b1eec7de61117b7c0a7914761e3da2eda upstream.

Commit 52cdbdd49853 (driver core: correct device's shutdown order)
introduced a regression by breaking device shutdown on some systems.

Namely, the devices_kset_move_last() call in really_probe() added by
that commit is a mistake as it may cause parents to follow children
in the devices_kset list which then causes shutdown to fail.  For
example, if a device has children before really_probe() is called
for it (which is not uncommon), that call will cause it to be
reordered after the children in the devices_kset list and the
ordering of that list will not reflect the correct device shutdown
order any more.

Also it causes the devices_kset list to be constantly reordered
until all drivers have been probed which is totally pointless
overhead in the majority of cases and it only covered an issue
with system shutdown, while system-wide suspend/resume potentially
had the same issue on the affected platforms (which was not covered).

Moreover, the shutdown issue originally addressed by the change in
really_probe() made by commit 52cdbdd49853 is not present in 4.18-rc
any more, since dra7 started to use the sdhci-omap driver which
doesn't disable any regulators during shutdown, so the really_probe()
part of commit 52cdbdd49853 can be safely reverted.  [The original
issue was related to the omap_hsmmc driver used by dra7 previously.]

For the above reasons, revert the really_probe() modifications made
by commit 52cdbdd49853.

The other code changes made by commit 52cdbdd49853 are useful and
they need not be reverted.

Fixes: 52cdbdd49853 (driver core: correct device's shutdown order)
Link: https://lore.kernel.org/lkml/CAFgQCTt7VfqM=UyCnvNFxrSw8Z6cUtAi3HUwR4_xPAc03SgHjQ@mail.gmail.com/
Reported-by: Pingfan Liu 
Tested-by: Pingfan Liu 
Reviewed-by: Kishon Vijay Abraham I 
Signed-off-by: Rafael J. Wysocki 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman