net: ipa: add IPA v5.0 GSI register definitions

Add the definitions of GSI register offsets and fields for IPA v5.0.
These are used for the SDX65 SoC. Increase the maximum channel and
event ring co

net: ipa: add IPA v5.0 GSI register definitions

Add the definitions of GSI register offsets and fields for IPA v5.0.
These are used for the SDX65 SoC. Increase the maximum channel and
event ring counts supported by the driver, so those implemented by
the SDX65 are supported.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: kill gsi->virt_raw

Starting at IPA v4.5, almost all GSI registers had their offsets
changed by a fixed amount (shifted downward by 0xd000). Rather than
defining offsets for all those regi

net: ipa: kill gsi->virt_raw

Starting at IPA v4.5, almost all GSI registers had their offsets
changed by a fixed amount (shifted downward by 0xd000). Rather than
defining offsets for all those registers dependent on version, an
adjustment was applied for most register accesses. This was
implemented in commit cdeee49f3ef7f ("net: ipa: adjust GSI register
addresses"). It was later modified to be a bit more obvious about
the adjusment, in commit 571b1e7e58ad3 ("net: ipa: use a separate
pointer for adjusted GSI memory").

We now are able to define every GSI register with its own offset, so
there's no need to implement this special adjustment.

So get rid of the "virt_raw" pointer, and just maintain "virt" as
the (non-adjusted) base address of I/O mapped GSI register memory.

Redefine the offsets of all GSI registers (other than the INTER_EE
ones, which were not subject to the adjustment) for IPA v4.5+,
subtracting 0xd000 from their defined offsets instead.

Move the ERROR_LOG and ERROR_LOG_CLR definitions further down in the
register definition files so all registers are defined in order of
their offset.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

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net: ipa: start creating GSI register definitions

Create a new register definition file in the "reg" subdirectory,
and begin populating it with GSI register definitions based on IPA
version. The GS

net: ipa: start creating GSI register definitions

Create a new register definition file in the "reg" subdirectory,
and begin populating it with GSI register definitions based on IPA
version. The GSI registers haven't changed much, so several IPA
versions can share the same GSI register definitions.

As with IPA registers, an array of pointers indexed by GSI register ID
refers to these register definitions, and a new "regs" field in the
GSI structure is initialized in gsi_reg_init() to refer to register
information based on the IPA version (though for now there's only
one). The new function gsi_reg() returns register information for
a given GSI register, and the result can be used to look up that
register's offset.

This patch is meant only to put the infrastructure in place, so only
eon register (CH_C_QOS) is defined for each version, and only the
offset and stride are defined for that register. Use new function
gsi_reg() to look up that register's information to get its offset,
This makes the GSI_CH_C_QOS_OFFSET() unnecessary, so get rid of it.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: update copyrights

Some source files state copyright dates that are earlier than the
last modification of the file. Change the copyright year to 2022 in
all such cases.

Signed-off-by: Ale

net: ipa: update copyrights

Some source files state copyright dates that are earlier than the
last modification of the file. Change the copyright year to 2022 in
all such cases.

Signed-off-by: Alex Elder <elder@linaro.org>
Link: https://lore.kernel.org/r/20220930224549.3503434-1-elder@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: move the definition of gsi_ee_id

Move the definition of the gsi_ee_id enumerated type out of "gsi.h"
and into "ipa_version.h". That latter header file isolates the
definition of the ipa_v

net: ipa: move the definition of gsi_ee_id

Move the definition of the gsi_ee_id enumerated type out of "gsi.h"
and into "ipa_version.h". That latter header file isolates the
definition of the ipa_version enumerated type, allowing it to be
included in both IPA and GSI code. We have the same requirement for
gsi_ee_id, and moving it here makes it easier to get only that
definition without everything else defined in "gsi.h".

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: kill all other transaction lists

None of the transaction lists are actually needed any more, because
transaction IDs (which have been shown to be equivalent) are used
instead. So we can r

net: ipa: kill all other transaction lists

None of the transaction lists are actually needed any more, because
transaction IDs (which have been shown to be equivalent) are used
instead. So we can remove all of them, as well as the spinlock
that protects updates to them.

Not requiring a lock simplifies gsi_trans_free() as well; we only
need to check the reference count once to decide whether we've hit
the last reference.

This makes the links field in the gsi_trans structure unused, so get
rid of that as well.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: kill the allocated transaction list

The only place the trans_info->alloc list is used is when
initializing it, when adding a transaction to it when allocation
finishes, and when moving a t

net: ipa: kill the allocated transaction list

The only place the trans_info->alloc list is used is when
initializing it, when adding a transaction to it when allocation
finishes, and when moving a transaction from that list to the
committed list.

We can just skip putting a transaction on the allocated list, and
add it (rather than move it) to the committed list when it is
committed.

On additional caveat is that an allocated transaction that's
committed without any TREs added will be immediately freed. Because
we aren't adding allocated transactions to a list any more, the
list links need to be initialized to ensure they're valid at the
time list_del() is called for the transaction.

Then we can safely eliminate the allocated transaction list.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: track polled transactions with an ID

Add a transaction ID to track the first element in the transaction
array that has been polled. Advance the ID when we are releasing a
transaction.

Te

net: ipa: track polled transactions with an ID

Add a transaction ID to track the first element in the transaction
array that has been polled. Advance the ID when we are releasing a
transaction.

Temporarily add warnings that verify that the first polled
transaction tracked by the ID matches the first element on the
polled list, both when polling and freeing.

Remove the temporary warnings added by the previous commit.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: track completed transactions with an ID

Add a transaction ID field to track the first element in the
transaction array that has completed but has not yet been polled.

Advance the ID when

net: ipa: track completed transactions with an ID

Add a transaction ID field to track the first element in the
transaction array that has completed but has not yet been polled.

Advance the ID when we are processing a transaction in the NAPI
polling loop (where completed transactions become polled).

Temporarily add warnings that verify that the first completed
transaction tracked by the ID matches the first element on the
completed list, both when pending and completing.

Remove the temporary warnings added by the previous commit.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: track pending transactions with an ID

Add a transaction ID field to track the first element in the
transaction array that is pending (sent to hardware) but not yet
complete. Advance the I

net: ipa: track pending transactions with an ID

Add a transaction ID field to track the first element in the
transaction array that is pending (sent to hardware) but not yet
complete. Advance the ID when a completion event for a channel
indicates that transactions have completed.

Temporarily add warnings that verify that the first pending
transaction tracked by the ID matches the first element on the
pending list, both when pending and completing, as well as when
resetting the channel.

Remove the temporary warnings added by the previous commit.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: track committed transactions with an ID

Add a transaction ID field to track the first element in a channel's
transaction array that has been committed, but not yet passed to the
hardware.

net: ipa: track committed transactions with an ID

Add a transaction ID field to track the first element in a channel's
transaction array that has been committed, but not yet passed to the
hardware. Advance the ID when the hardware is notified via doorbell
that TREs from a transaction are ready for consumption.

Temporarily add warnings that verify that the first committed
transaction tracked by the ID matches the first element on the
committed list, both when committing and pending (at doorbell).

Remove the temporary warnings added by the previous commit.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: track allocated transactions with an ID

Transactions for a channel are now managed in an array, with a free
transaction ID indicating which is the next one free.

Add another transaction I

net: ipa: track allocated transactions with an ID

Transactions for a channel are now managed in an array, with a free
transaction ID indicating which is the next one free.

Add another transaction ID field to track the first element in the
array that has been allocated. Advance it when a transaction is
committed (because that is when that transaction leaves allocated
state).

Temporarily add warnings that verify that the first allocated
transaction tracked by the ID matches the first element on the
allocated list, both when allocating and committing a transaction.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: use an array for transactions

Transactions are always allocated one at a time. The maximum number
of them we could ever need occurs if each TRE is assigned to a
transaction. So a channel

net: ipa: use an array for transactions

Transactions are always allocated one at a time. The maximum number
of them we could ever need occurs if each TRE is assigned to a
transaction. So a channel requires no more transactions than the
number of TREs in its transfer ring. That number is known to be a
power-of-2 less than 65536.

The transaction pool abstraction is used for other things, but for
transactions we can use a simple array of transaction structures,
and use a free index to indicate which entry in the array is the
next one free for allocation.

By having the number of elements in the array be a power-of-2, we
can use an ever-incrementing 16-bit free index, and use it modulo
the array size. Distinguish a "trans_id" (whose value can exceed
the number of entries in the transaction array) from a "trans_index"
(which is less than the number of entries).

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: rearrange transaction initialization

The transaction map is really associated with the transaction pool;
move its definition earlier in the gsi_trans_info structure.

Rearrange initializat

net: ipa: rearrange transaction initialization

The transaction map is really associated with the transaction pool;
move its definition earlier in the gsi_trans_info structure.

Rearrange initialization in gsi_channel_trans_init() so it
sets the tre_avail value first, then initializes the transaction
pool, and finally allocating the transaction map.

Update comments.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: add a transaction committed list

We currently put a transaction on the pending list when it has
been committed. But until the channel's doorbell rings, these
transactions aren't actually

net: ipa: add a transaction committed list

We currently put a transaction on the pending list when it has
been committed. But until the channel's doorbell rings, these
transactions aren't actually "owned" by the hardware yet.

Add a new "committed" state (and list), to represent transactions
that have been committed but not yet sent to hardware. Define
"pending" to mean committed transactions that have been sent
to hardware but have not yet completed.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: initialize ring indexes to 0

When a GSI channel is initially allocated, and after it has been
reset, the hardware assumes its ring index is 0. And although we
do initialize channels this

net: ipa: initialize ring indexes to 0

When a GSI channel is initially allocated, and after it has been
reset, the hardware assumes its ring index is 0. And although we
do initialize channels this way, the comments in the IPA code don't
really explain this. For event rings, it doesn't matter what value
we use initially, so using 0 is just fine.

Add some information about the assumptions made by hardware above
the definition of the gsi_ring structure in "gsi.h".

Zero the index field for all rings (channel and event) when the ring
is allocated. As a result, that function initializes all fields in
the structure.

Stop zeroing the index the top of gsi_channel_program(). Initially
we'll use the index value set when the channel ring was allocated.
And we'll explicitly zero the index value in gsi_channel_reset()
before programming the hardware, adding a comment explaining why
it's required.

For event rings, use the index initialized by gsi_ring_alloc()
rather than 0 when ringing the doorbell in gsi_evt_ring_program().
(It'll still be zero, but we won't assume that to be the case.)

Use a local variable in gsi_evt_ring_program() that represents the
address of the event ring's ring structure.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: stop counting total RX bytes and transactions

In gsi_evt_ring_rx_update(), we update each transaction so its len
field reflects the actual number of bytes received. In the process,
the to

net: ipa: stop counting total RX bytes and transactions

In gsi_evt_ring_rx_update(), we update each transaction so its len
field reflects the actual number of bytes received. In the process,
the total number of transactions and bytes processed on the channel
are summed, and added to a running total for the channel.

But we don't actually use those running totals for RX endpoints.
They're maintained for TX channels to support CoDel when they are
associated with a "real" network device.

So stop maintaining these totals for RX endpoints, and update the
comment where the fields are defined to make it clear they're only
valid for TX channels.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: rename channel->tlv_count

Each GSI channel has a TLV FIFO of a certain size, specified in the
configuration data for an AP channel. That size dictates the
maximum number of TREs that are

net: ipa: rename channel->tlv_count

Each GSI channel has a TLV FIFO of a certain size, specified in the
configuration data for an AP channel. That size dictates the
maximum number of TREs that are allowed in a single transaction.

The only way that value is used after initialization is as a limit
on the number of TREs in a transaction; calling it "tlv_count"
isn't helpful, and in fact gsi_channel_trans_tre_max() exists to
sort of abstract it.

Instead, rename the channel->tlv_count field trans_tre_max, and get
rid of the helper function. Update a couple of comments as well.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: remove command info pool

The ipa_cmd_info structure now contains only one field, and it's an
enumerated type whose values all fit in 8 bits. Currently we'll
never use more than 8 TREs in

net: ipa: remove command info pool

The ipa_cmd_info structure now contains only one field, and it's an
enumerated type whose values all fit in 8 bits. Currently we'll
never use more than 8 TREs in a command transaction, and we can
represent that number of command opcodes in the same space as a 64
bit pointer to an ipa_cmd_info structure.

Define IPA_COMMAND_TRANS_TRE_MAX as the maximum number of TREs that
can be in a command transaction. Replace the info pointer in a
transaction with a fixed-size array named cmd_opcode[] of that many
bytes. Store the opcode in this array when adding a command TRE to
a transaction, as was done previously for the info array. This
makes the ipa_cmd_info unused, so get rid of it.

When committing an immediate command transaction, use the channel's
Boolean command flag to determine whether to fill in the opcode,
which will be taken (as before) from the array in the transaction.

This makes the command info pool unnecessary, so get rid of it.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: support enhanced channel flow control

IPA v4.2 introduced GSI channel flow control, used instead of IPA
endpoint DELAY mode to prevent a TX channel from injecting packets
into the IPA core

net: ipa: support enhanced channel flow control

IPA v4.2 introduced GSI channel flow control, used instead of IPA
endpoint DELAY mode to prevent a TX channel from injecting packets
into the IPA core. It used a new FLOW_CONTROLLED channel state
which could be entered using GSI generic commands.

IPA v4.11 extended the channel flow control model. Rather than
having a distinct FLOW_CONTROLLED channel state, each channel has a
"flow control" property that can be enabled or not--independent of
the channel state. The AP (or modem) can modify this property using
the same GSI generic commands as before.

The AP only uses channel flow control on modem TX channels, and only
when recovering from a modem crash. The AP has no way to discover
the state of a modem channel, so the fact that (starting with IPA
v4.11) flow control no longer uses a distinct channel state is
invisible to the AP. So enhanced flow control generally does not
change the way AP uses flow control.

There are a few small differences, however:
- There is a notion of "primary" or "secondary" flow control, and
when enabling or disabling flow control that must be specified
in a new field in the GSI generic command register. For now, we
always specify 0 (meaning "primary").
- When disabling flow control, it's possible a request will need
to be retried. We retry up to 5 times in this case.
- Another new generic command allows the current flow control
state to be queried. We do not use this.

Other than the need for retries, the code essentially works the same
way as before.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: introduce channel flow control

One quirk for certain versions of IPA is that endpoint DELAY mode
does not work properly. IPA DELAY mode prevents any packets from
being delivered to the IP

net: ipa: introduce channel flow control

One quirk for certain versions of IPA is that endpoint DELAY mode
does not work properly. IPA DELAY mode prevents any packets from
being delivered to the IPA core for processing on a TX endpoint.
The AP uses DELAY mode when the modem crashes, to prevent modem TX
endpoints from generating traffic during crash recovery. Without
this, there is a chance the hardware will stall during recovery from
a modem crash.

To achieve a similar effect, a GSI FLOW_CONTROLLED channel state
was created. A STARTED TX channel can be placed in FLOW_CONTROLLED
state, which prevents the transfer of any more packets. A channel
in FLOW_CONTROLLED state can be either returned to STARTED state, or
can be transitioned to STOPPED state.

Because this operates on GSI channels, two generic commands were
added to allow the AP to control this state for modem channels
(similar to the ALLOCATE and HALT channel commands).

Previously the code assumed this quirk only applied to IPA v4.2.
In fact, channel flow control (rather than endpoint DELAY mode)
should be used for all versions *starting* with IPA v4.2.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: rearrange GSI structure fields

The dummy net_device is a large field in the GSI structure, but it
is not at all interesting from the perspective of debugging. Move
it to the end of the GS

net: ipa: rearrange GSI structure fields

The dummy net_device is a large field in the GSI structure, but it
is not at all interesting from the perspective of debugging. Move
it to the end of the GSI structure so the other fields are easier to
find in memory.

The channel and event ring arrays are also very large, so move them
near the end of the structure as well.

Swap the position of the result and completion fields to improve
structure packing.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: GSI only needs one completion

A mutex ensures we never submit more than one GSI command of any
kind at once. This means the per-channel and per-event ring
completion structures provide no

net: ipa: GSI only needs one completion

A mutex ensures we never submit more than one GSI command of any
kind at once. This means the per-channel and per-event ring
completion structures provide no benefit. Instead, just use the
single (existing) GSI completion to signal the completion of GSI
commands of all types.

This makes gsi_evt_ring_init() a trivial function with no inverse,
so open-code it in its sole caller and get rid of the function.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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net: ipa: disable GSI interrupts while suspended

Introduce new functions gsi_suspend() and gsi_resume(), which will
disable the GSI interrupt handler after all endpoints are suspended
and re-enable

net: ipa: disable GSI interrupts while suspended

Introduce new functions gsi_suspend() and gsi_resume(), which will
disable the GSI interrupt handler after all endpoints are suspended
and re-enable it before endpoints are resumed. This will ensure no
GSI interrupt handler will fire when the hardware is suspended.

Here's a little further explanation. There are seven GSI interrupt
types, and most are disabled except when needed.
- These two are not used (never enabled):
GSI_INTER_EE_CH_CTRL
GSI_INTER_EE_EV_CTRL
- These two are only used to implement channel and event ring
commands, and are only enabled while a command is underway:
GSI_CH_CTRL
GSI_EV_CTRL
- The IEOB interrupt signals I/O completion. It will not fire
when a channel is stopped (or "suspended").
GSI_IEOB
- This interrupt is used to allocate or halt modem channels,
and is only enabled while such a command is underway.
GSI_GLOB_EE
However it also is used to signal certain errors, and this could
occur at any time.
- The general interrupt signals general errors, and could occur at
any time.
GSI_GENERAL

The purpose for this change is to ensure no global or general
interrupts fire due to errors while the hardware is suspended.
We enable the clock on resume, and at that time we can "handle"
(at least report) these error conditions.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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net: ipa: use gsi->version for channel suspend/resume

The GSI layer has the IPA version now, so there's no need for
version-specific flags to be passed from IPA. One instance of
this is in gsi_chan

net: ipa: use gsi->version for channel suspend/resume

The GSI layer has the IPA version now, so there's no need for
version-specific flags to be passed from IPA. One instance of
this is in gsi_channel_suspend() and gsi_channel_resume(), which
indicate whether or not the endpoint suspend is implemented by
GSI stopping the channel. We can make that determination based
on gsi->version, eliminating the need for a Boolean flag in those
functions.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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