net: ipa: reg: include <linux/bug.h>

When "reg.h" got created, it included calls to WARN() and WARN_ON().
Those macros are defined via <linux/bug.h>. In addition, it uses
is_power_of_2(), which is defined in <linux/log2.h>. Include those
files so IPA "reg.h" has access to all definitions it requires.

Meanwhile, <linux/bits.h> is included but nothing defined therein
is required directly in "reg.h", so get rid of that.

Fixes: 81772e444dbe ("net: ipa: start generalizing "ipa_reg"")
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: ipa: generalize register field functions

Rename functions related to register fields so they don't appear to
be IPA-specific, and move their definitions into "reg.h":
ipa_reg_fmask() -> reg_fmask()
ipa_reg_bit() -> reg_bit()
ipa_reg_field_max() -> reg_field_max()
ipa_reg_encode() -> reg_encode()
ipa_reg_decode() -> reg_decode()

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

net: ipa: generalize register offset functions

Rename ipa_reg_offset() to be reg_offset() and move its definition
to "reg.h". Rename ipa_reg_n_offset() to be reg_n_offset() also.

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

net: ipa: start generalizing "ipa_reg"

IPA register definitions have evolved with each new version. The
changes required to support more than 32 endpoints in IPA v5.0 made
it best to define a unified mechanism for defining registers and
their fields.

GSI register definitions, meanwhile, have remained fairly stable.
And even as the total number of IPA endpoints goes beyond 32, the
number of GSI channels on a given EE that underly endpoints still
remains 32 or less.

Despite that, GSI v3.0 (which is used with IPA v5.0) extends the
number of channels (and events) it supports to be about 256, and as
a result, many GSI register definitions must change significantly.
To address this, we'll use the same "ipa_reg" mechanism to define
the GSI registers.

As a first step in generalizing the "ipa_reg" to also support GSI
registers, isolate the definitions of the "ipa_reg" and "ipa_regs"
structure types (and some supporting macros) into a new header file,
and remove the "ipa_" and "IPA_" from symbol names.

Separate the IPA register ID validity checking from the generic
check that a register ID is in range. Aside from that, this is
intended to have no functional effect on the code.

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