bnxt_en: Skip nic close/open when configuring tstamp filters

We don't have to close and open the nic to make sure we have
valid rx timestamps. Once we have the timestamp filter applied to
the HW and the timestamp_fld_format bit is cleared in the rx
completion and the timestamp is non-zero, we can be sure that rx
timestamp is valid data.

Skip close/open when we set any timestamp filter.

Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20231212005122.2401-13-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

bnxt_en: Add a non-real time mode to access NIC clock

When using a PHC that is shared between multiple hosts,
in order to achieve consistent timestamps across all hosts,
we need to isolate the PHC from any host making frequency
adjustments.

This patch adds a non-real time mode for this purpose.
The implementation is based on a free running NIC hardware timer
which is used as the timestamper time-base. Each host implements
individual adjustments to a local timecounter based on the NIC free
running timer.

Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Reviewed-by: Andy Gospodarek <andrew.gospodarek@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

bnxt_en: Configure ptp filters during bnxt open

For correctness, we need to configure the packet filters for timestamping
during bnxt_open. This way they are always configured after firmware
reset or chip reset. We should not assume that the filters will always
be retained across resets.

This patch modifies the ioctl handler and always configures the PTP
filters in the bnxt_open() path.

Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: bnxt_ptp: fix compilation error

The Broadcom bnxt_ptp driver does not compile with GCC 11.2.2 when
CONFIG_WERROR is enabled. The following error is generated:

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c: In function ‘bnxt_ptp_enable’:
drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:400:43: error: array
subscript 255 is above array bounds of ‘struct pps_pin[4]’
[-Werror=array-bounds]
400 | ptp->pps_info.pins[pin_id].event = BNXT_PPS_EVENT_EXTERNAL;
| ~~~~~~~~~~~~~~~~~~^~~~~~~~
In file included from drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.c:20:
drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h:75:24: note: while
referencing ‘pins’
75 | struct pps_pin pins[BNXT_MAX_TSIO_PINS];
| ^~~~
cc1: all warnings being treated as errors

This is due to the function ptp_find_pin() returning a pin ID of -1 when
a valid pin is not found and this error never being checked.
Change the TSIO_PIN_VALID() function to also check that a pin ID is not
negative and use this macro in bnxt_ptp_enable() to check the result of
the calls to ptp_find_pin() to return an error early for invalid pins.
This fixes the compilation error.

Cc: <stable@vger.kernel.org>
Fixes: 9e518f25802c ("bnxt_en: 1PPS functions to configure TSIO pins")
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Link: https://lore.kernel.org/r/20220328062708.207079-1-damien.lemoal@opensource.wdc.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

bnxt_en: Implement .adjtime() for PTP RTC mode

The adjusted time is set in the PHC in RTC mode. We also need to
update the snapshots ptp->current_time and ptp->old_time when the
time is adjusted.

Cc: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Add driver support to use Real Time Counter for PTP

Add support for RTC mode if it is supported by firmware. In RTC
mode, the PHC is set to the 64-bit clock. Because the legacy interface
is 48-bit, the driver still has to keep track of the upper 16 bits and
handle the rollover.

Cc: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: implement devlink dev reload driver_reinit

The RTNL lock must be held between down and up to prevent interleaving
state changes, especially since external state changes might release
and allocate different driver resource subsets that would otherwise
need to be tracked and carefully handled. If the down function fails,
then devlink will not call the corresponding up function, thus the
lock is released in the down error paths.

v2: Don't use devlink_reload_disable() and devlink_reload_enable().
Instead, check that the netdev is not in unregistered state before
proceeding with reload.

Signed-off-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-Off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Event handler for PPS events

Once the PPS pins are configured, the FW can report
PPS values using ASYNC event. This patch adds the
ASYNC event handler and subsequent reporting of the
events to kernel.

Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: 1PPS functions to configure TSIO pins

Application will send ioctls to set/clear PPS pin functions
based on user input. This patch implements the driver
callbacks that will configure the TSIO pins using firmware
commands. After firmware reset, the TSIO pins will be reconfigured
again.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: 1PPS support for 5750X family chips

1PPS (One Pulse Per Second) is a signal generated either
by the NIC PHC or an external timing source.
Integrating the support to configure and use 1PPS using
the TSIO pins along with PTP timestamps will add Grand
Master capability to the 5750X family chipsets.

This patch initializes the driver data structures and
registers the 1PPS with kernel, based on the TSIO pins'
capability in the hardware. This will create a /dev/ppsX
device which applications can use to receive PPS events.

Later patches will define functions to configure and use
the pins.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Use register window 6 instead of 5 to read the PHC

Some older Broadcom debug tools use window 5 and may conflict, so switch
to use window 6 instead.

Fixes: 118612d519d8 ("bnxt_en: Add PTP clock APIs, ioctls, and ethtool methods")
Reviewed-by: Andy Gospodarek <gospo@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Update firmware call to retrieve TX PTP timestamp

New firmware interface requires the PTP sequence ID header offset to
be passed to the firmware to properly find the matching timestamp
for all protocols.

Fixes: 83bb623c968e ("bnxt_en: Transmit and retrieve packet timestamps")
Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Add missing periodic PHC overflow check

We use the timecounter APIs for the 48-bit PHC and packet timestamps.
We must periodically update the timecounter at roughly half the
overflow interval. The overflow interval is about 78 hours, so
update it every 19 hours (1/4 interval) for some extra margins.

Fixes: 390862f45c85 ("bnxt_en: Get the full 48-bit hardware timestamp periodically")
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Move bnxt_ptp_init() to bnxt_open()

The device needs to be in ifup state for PTP to function, so move
bnxt_ptp_init() to bnxt_open(). This means that the PHC will be
registered during bnxt_open().

This also makes firmware reset work correctly. PTP configurations
may change after firmware upgrade or downgrade. bnxt_open() will
be called after firmware reset, so it will work properly.

bnxt_ptp_start() is now incorporated into bnxt_ptp_init(). We now
also need to call bnxt_ptp_clear() in bnxt_close().

Fixes: 93cb62d98e9c ("bnxt_en: Enable hardware PTP support")
Cc: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Transmit and retrieve packet timestamps

Setup the TXBD to enable TX timestamp if requested. At TX packet DMA
completion, if we requested TX timestamp on that packet, we defer to
.do_aux_work() to obtain the TX timestamp from the firmware before we
free the TX SKB.

v2: Use .do_aux_work() to get the TX timestamp from firmware.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Get the RX packet timestamp

If the RX packet is timestamped by the hardware, the RX completion
record will contain the lower 32-bit of the timestamp. This needs
to be combined with the upper 16-bit of the periodic timestamp that
we get from the timer. The previous snapshot in ptp->old_timer is
used to make sure that the snapshot is not ahead of the RX timestamp
and we adjust for wrap-around if needed.

v2: Make ptp->old_time read access safe on 32-bit CPUs.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Get the full 48-bit hardware timestamp periodically

From the bnxt_timer(), read the 48-bit hardware running clock
periodically and store it in ptp->current_time. The previous snapshot
of the clock will be stored in ptp->old_time. The old_time snapshot
will be used in the next patches to compute the RX packet timestamps.

v2: Use .do_aux_work() to read the timer periodically.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Add PTP clock APIs, ioctls, and ethtool methods

Add the clock APIs to set/get/adjust the hw clock, and the related
ioctls and ethtool methods.

v2: Propagate error code from ptp_clock_register().
Add spinlock to serialize access to the timecounter. The
timecounter is accessed in process context and the RX datapath.
Read the PHC using direct registers.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

bnxt_en: Get PTP hardware capability from firmware

Store PTP hardware info in a structure if hardware and firmware support PTP.

Reviewed-by: Edwin Peer <edwin.peer@broadcom.com>
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>