Like i.MX8 SCU, i.MX8ULP S4 also has vendor specific protocol.
 - bind SCU/S4 MU part to share one tx/rx/init API to make code simple.
 - S4 msg max size is very large, so alloc the space at driver probe,
   not use local on stack variable.
 - S4 MU has 8 TR and 4 RR which is different with i.MX8 MU, so adapt
   code to reflect this.

   Tested on i.MX8MP, i.MX8ULP

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Move the PCCT subspace parsing and allocation into pcc_mbox_probe so
that we can get rid of global PCC channel and mailbox controller data.
It also helps to make use of devm_* APIs for all the allocations.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

With all the plumbing in place to avoid accessing PCCT type and other
fields directly from the PCCT table all the time, let us now add the
support for extended PCC subspaces(type 3 and 4).

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

pcc_chan_reg_init now checks if the register bit width is within the
list [8, 16, 32, 64] and flags error if that is not the case. Therefore
there is no need to handling invalid bit-width in both read_register
and write_register. We can drop that along with the return values for
these 2 functions.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Now that the con_priv is availvale solely for PCC mailbox controller
driver, let us use the same to save the channel specific information
in it so that we can it whenever required instead of parsing the PCCT
table entries every time in both pcc_send_data and pcc_mbox_irq.

We can now use the newly introduces PCC register bundle to simplify both
saving of channel specific information and accessing them without repeated
checks for the subspace type.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Extended PCC subspaces introduces more registers into the PCCT. In order
to consolidate access to these registers and to keep all the details
contained in one place, let us introduce PCC register bundle that holds
the ACPI Generic Address Structure as well as the virtual address for
the same if it is mapped in the OS.

It also contains the various masks used to access the register and
the associated read, write and read-modify-write accessors.

We can also clean up the initialisations by having a helper function
for the same.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

The specification refers this register and associated bitmask as platform
interrupt acknowledge register. Let us rename it so that it is easier to
map and understand.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Now that we have all the shared memory region information populated in
the pcc_mbox_chan, let us propagate the pointer to the same as the
return value to pcc_mbox_request channel.

This eliminates the need for the individual users of PCC mailbox to
parse the PCCT subspace entries and fetch the shmem information. This
also eliminates the need for PCC mailbox controller to set con_priv to
PCCT subspace entries. This is required as con_priv is private to the
controller driver to attach private data associated with the channel and
not meant to be used by the mailbox client/users.

Let us convert all the users of pcc_mbox_{request,free}_channel to use
new interface.

Cc: Jean Delvare <jdelvare@suse.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Currently PCC mailbox controller sets con_priv in each channel to hold
the pointer to pcct subspace entry it corresponds to. The mailbox user
will then fetch this pointer from the channel descriptor they get when
they request for the channel. Using that pointer they then parse the
pcct entry again to fetch all the information about shared memory region.

In order to remove individual users of PCC mailbox parsing the PCCT
subspace entries to fetch same information, let us consolidate the same
in pcc mailbox controller by parsing all the shared memory region
information into a structure that can also hold the mbox_chan pointer it
represent.

This can then be used as main PCC mailbox channel pointer that we can
return as part of pcc_mbox_request_channel instead of standard mailbox
channel pointer.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

Extended PCC subspaces(Type 3 and 4) differ from generic(Type 0) and
HW-Reduced Communication(Type 1 and 2) subspace structures. However some
fields share same offsets and same type of structure can be use to
extract the fields. In order to simplify that, let us move all the doorbell
register parsing into pcc_parse_subspace_db_reg and consolidate there.
It will be easier to extend it if required within the same.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>