Commit Graph

7 Commits

Author SHA1 Message Date
Ivan Vecera
2dbf9b7562 dpll: zl3073x: add channel ToD, phase step and TIE operations
Add low-level DPLL channel operations for ToD read/write/adjust,
output phase step, delta frequency offset write and TIE (Time
Interval Error) write. These serve as building blocks for the PTP
clock callbacks added in the next patch.

ToD operations use a wait-before-write pattern to avoid blocking
after each operation.

The tod_ready_wait helper selects the poll timeout based on the
current ToD command - write operations use a longer timeout (1000 ms)
than reads (30 ms).

The ToD read captures system timestamps (ptp_system_timestamp) around
the HW command and completion poll to support cross-timestamping.

The TIE write operation provides sub-picosecond resolution phase
adjustment for modes where the DPLL is tracking a reference
(AUTO and REFLOCK).

Add output step-time mask to struct zl3073x_dev and
zl3073x_dev_out_is_stepped() helper to check if an output
participates in step-time operations.

Reviewed-by: Petr Oros <poros@redhat.com>
Tested-by: Chris du Quesnay <Chris.duQuesnay@microchip.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260814082656.306534-3-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-18 09:40:05 -07:00
Ivan Vecera
3553976ffe dpll: zl3073x: add NCO virtual input pin
Add a virtual NCO (Numerically Controlled Oscillator) input pin that
lets userspace switch a DPLL channel into NCO mode. A single NCO pin
is shared across all DPLL channels - each channel has its own
independent connection state. The NCO pin is registered with the new
DPLL_PIN_TYPE_INT_NCO type and reports DPLL_PIN_STATE_CONNECTED /
DPLL_PIN_OPERSTATE_ACTIVE when the channel is in NCO mode.

At NCO pin registration the following bits are configured in
dpll_ctrl_x:
  - nco_auto_read: auto-capture tracking offset on NCO entry
  - tod_step_reset: apply negated ToD step accumulator on NCO exit
  - tie_clear: PPS DPLLs set 1 to re-align outputs on NCO exit,
               EEC DPLLs keep 0 to prevent an unwanted TIE write

Before switching to NCO mode, dpll_df_read_x is configured with
ref_ofst=0 and cmd=ACC_I so that nco_auto_read captures the
accumulated I-part offset relative to the master clock. Without
this, the captured df_offset would be near zero (offset relative
to the input reference after lock).

On NCO entry the df_offset captured by nco_auto_read is read from
the register. Per the datasheet, nco_auto_read only captures a valid
offset when entering NCO from reflock, auto or holdover mode; from
freerun the captured value is not meaningful and df_offset is marked as
ZL_DPLL_DF_OFFSET_UNKNOWN. The same sentinel is set in
chan_state_update() when the channel is not locked, and both FFO
consumers (NCO pin and input pin) guard against it.

Disconnecting the NCO pin switches to freerun rather than holdover
because holdover averaging is not updated during NCO mode.

When connecting the NCO pin displaces a previously connected input
pin (reflock mode), a change notification is sent for that input pin.

Input reference pins are now always registered regardless of the
initial DPLL mode. Previously they were skipped when the DPLL was
in NCO mode, but the NCO pin provides the proper mechanism for
mode transitions.

Reviewed-by: Petr Oros <poros@redhat.com>
Tested-by: Chris du Quesnay <Chris.duQuesnay@microchip.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260630125536.720717-6-ivecera@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-06 14:45:05 +02:00
Ivan Vecera
2b11bde391 dpll: zl3073x: use per-operation poll timeouts
Replace the single 2s timeout in zl3073x_poll_zero_u8() with a
per-caller timeout parameter. Different HW operations have different
expected completion times so using per-operation timeouts improves
error detection. The timeout values are based on proprietary source
code provided by Microchip and own measurement.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Reviewed-by: Petr Oros <poros@redhat.com>
Link: https://patch.msgid.link/20260630125536.720717-4-ivecera@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-06 14:45:05 +02:00
Ivan Vecera
54e65df8cf dpll: zl3073x: report FFO as DPLL vs input reference offset
Replace the per-reference frequency offset measurement (which was
redundant with measured-frequency) with a direct read of the DPLL's
delta frequency offset vs its tracked input reference.

The new implementation uses the dpll_df_offset_x register with
ref_ofst=1 via the dpll_df_read_x semaphore mechanism. This
provides 2^-48 resolution (~3.5 fE) and reports the actual
frequency difference between the DPLL and its active input.

Switch supported_ffo from DPLL_FFO_PORT_RXTX_RATE to
DPLL_FFO_PIN_DEVICE so FFO is reported only in the per-parent
context for the active input pin.

Use atomic64_t for freq_offset to prevent torn reads on 32-bit
architectures between the periodic worker and netlink callbacks.

Rewrite ffo_check to compare the cached df_offset converted to PPT
instead of using the old per-reference measurement. Remove the
ref_ffo_update periodic measurement and the ref ffo field since
they are no longer needed.

Changes v3 -> v4:
- Switch to DPLL_FFO_PIN_DEVICE, remove dpll=NULL guard
- Use atomic64_t for freq_offset (torn read on 32-bit)

Reviewed-by: Petr Oros <poros@redhat.com>
Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260511155816.99936-3-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-05-12 18:48:07 -07:00
Ivan Vecera
f6b075bc3a dpll: zl3073x: add reference priority to zl3073x_chan
Cache the ZL_REG_DPLL_REF_PRIO registers in the zl3073x_chan cfg group.
These mailbox-based registers store per-reference priority values
(4 bits each, P/N packed) used for automatic reference selection.

Add ref_prio[] array to struct zl3073x_chan and provide inline helpers
zl3073x_chan_ref_prio_get(), zl3073x_chan_ref_prio_set(), and
zl3073x_chan_ref_is_selectable() for nibble-level access and priority
queries. Extend state_fetch and state_set with DPLL mailbox operations
to read and write the priority registers.

Replace the ad-hoc zl3073x_dpll_ref_prio_get/set functions in dpll.c
with the cached state pattern, removing direct mailbox access from
the DPLL layer. This also simplifies pin registration since reading
priority from cached state cannot fail.

Remove the pin->selectable flag from struct zl3073x_dpll_pin and
derive the selectable state from the cached ref priority via
zl3073x_chan_ref_is_selectable(), eliminating a redundant cache.

Inline zl3073x_dpll_selected_ref_set() into
zl3073x_dpll_input_pin_state_on_dpll_set(), unifying all manual and
automatic mode paths to commit changes through a single
zl3073x_chan_state_set() call at the end of the function.

Move hardware limit constants from core.h to regs.h so that chan.h
can reference ZL3073X_NUM_REFS for the ref_prio array size.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260315174224.399074-6-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-17 19:05:12 -07:00
Ivan Vecera
41bab554d7 dpll: zl3073x: add DPLL channel status fields to zl3073x_chan
Add mon_status and refsel_status fields to struct zl3073x_chan in a
stat group to cache the 'dpll_mon_status' and 'dpll_refsel_status'
registers.

Add zl3073x_chan_lock_state_get(), zl3073x_chan_is_ho_ready(),
zl3073x_chan_refsel_state_get() and zl3073x_chan_refsel_ref_get()
inline helpers for reading cached state, and zl3073x_chan_state_update()
for refreshing both registers from hardware. Call it from
zl3073x_chan_state_fetch() as well so that channel status is
initialized at device startup.

Call zl3073x_dev_chan_states_update() from the periodic work to
keep the cached state up to date and convert
zl3073x_dpll_lock_status_get() and zl3073x_dpll_selected_ref_get()
to use the cached state via the new helpers instead of direct register
reads.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260315174224.399074-5-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-17 19:05:12 -07:00
Ivan Vecera
3032e95987 dpll: zl3073x: introduce zl3073x_chan for DPLL channel state
Extract DPLL channel state management into a dedicated zl3073x_chan
module, following the pattern already established by zl3073x_ref,
zl3073x_out and zl3073x_synth.

The new struct zl3073x_chan caches the raw mode_refsel register value
in a cfg group with inline getters and setters to extract and update
the bitfields. Three standard state management functions are provided:

 - zl3073x_chan_state_fetch: read the mode_refsel register from HW
 - zl3073x_chan_state_get: return cached channel state
 - zl3073x_chan_state_set: write changed state to HW, skip if unchanged

The channel state array chan[ZL3073X_MAX_CHANNELS] is added to struct
zl3073x_dev. Channel state is fetched as part of
zl3073x_dev_state_fetch, using the chip-specific channel count.

The refsel_mode and forced_ref fields are removed from struct
zl3073x_dpll and all direct register accesses in dpll.c are replaced
with the new chan state operations.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
Link: https://patch.msgid.link/20260315174224.399074-4-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-17 19:05:12 -07:00