net: intel: introduce {, Intel} Ethernet common library

Not a secret there's a ton of code duplication between two and more Intel
ethernet modules.

Before introducing new changes, which would need to be copied over again,
start decoupling the already existing duplicate functionality into a new
module, which will be shared between several Intel Ethernet drivers.
Add the lookup table which converts 8/10-bit hardware packet type into
a parsed bitfield structure for easy checking packet format parameters,
such as payload level, IP version, etc. This is currently used by i40e,
ice and iavf and it's all the same in all three drivers.
The only difference introduced in this implementation is that instead of
defining a 256 (or 1024 in case of ice) element array, add unlikely()
condition to limit the input to 154 (current maximum non-reserved packet
type). There's no reason to waste 600 (or even 3600) bytes only to not
hurt very unlikely exception packets.
The hash computation function now takes payload level directly as a
pkt_hash_type. There's a couple cases when non-IP ptypes are marked as
L3 payload and in the previous versions their hash level would be 2, not
3. But skb_set_hash() only sees difference between L4 and non-L4, thus
this won't change anything at all.
The module is behind the hidden Kconfig symbol, which the drivers will
select when needed. The exports are behind 'LIBIE' namespace to limit
the scope of the functions.

Not that non-HW-specific symbols will live in yet another module,
libeth. This is done to easily distinguish pretty generic code ready
for reusing by any other vendor and/or for moving the layer up from
the code useful in Intel's 1-100G drivers only.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/Kconfig b/drivers/net/ethernet/intel/Kconfig
index 6e7901e12699..e0287fbd501d 100644
--- a/drivers/net/ethernet/intel/Kconfig
+++ b/drivers/net/ethernet/intel/Kconfig
@@ -16,6 +16,9 @@ config NET_VENDOR_INTEL
 
 if NET_VENDOR_INTEL
 
+source "drivers/net/ethernet/intel/libeth/Kconfig"
+source "drivers/net/ethernet/intel/libie/Kconfig"
+
 config E100
 	tristate "Intel(R) PRO/100+ support"
 	depends on PCI
@@ -225,6 +228,7 @@ config I40E
 	depends on PTP_1588_CLOCK_OPTIONAL
 	depends on PCI
 	select AUXILIARY_BUS
+	select LIBIE
 	select NET_DEVLINK
 	help
 	  This driver supports Intel(R) Ethernet Controller XL710 Family of
@@ -253,6 +257,8 @@ config I40E_DCB
 # so that CONFIG_IAVF symbol will always mirror the state of CONFIG_I40EVF
 config IAVF
 	tristate
+	select LIBIE
+
 config I40EVF
 	tristate "Intel(R) Ethernet Adaptive Virtual Function support"
 	select IAVF
@@ -283,6 +289,7 @@ config ICE
 	depends on GNSS || GNSS = n
 	select AUXILIARY_BUS
 	select DIMLIB
+	select LIBIE
 	select NET_DEVLINK
 	select PLDMFW
 	select DPLL