bus: Add Baikal-T1 AXI-bus driver

AXI3-bus is the main communication bus connecting all high-speed
peripheral IP-cores with RAM controller and MIPS P5600 cores on Baikal-T1
SoC. Bus traffic arbitration is done by means of DW AMBA 3 AXI
Interconnect (so called AXI Main Interconnect) routing IO requests from
one SoC block to another. This driver provides a way to detect any bus
protocol errors and device not responding situations by means of an
embedded on top of the interconnect errors handler block (EHB). AXI
Interconnect QoS arbitration tuning is currently unsupported.
The bus doesn't provide a way to detect the interconnected devices,
so they are supposed to be statically defined like by means of the
simple-bus sub-nodes.

[arnd: fix build warnings for missing includes and wrong return types]

Link: https://lore.kernel.org/r/20200526125928.17096-5-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: soc@kernel.org
Cc: devicetree@vger.kernel.org
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 15 insertions, 0 deletions

diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 6d4e4497b59b..1080dd26e268 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -29,6 +29,21 @@ config BRCMSTB_GISB_ARB
 	  arbiter. This driver provides timeout and target abort error handling
 	  and internal bus master decoding.
 
+config BT1_AXI
+	tristate "Baikal-T1 AXI-bus driver"
+	depends on MIPS_BAIKAL_T1 || COMPILE_TEST
+	select MFD_SYSCON
+	help
+	  AXI3-bus is the main communication bus connecting all high-speed
+	  peripheral IP-cores with RAM controller and with MIPS P5600 cores on
+	  Baikal-T1 SoC. Traffic arbitration is done by means of DW AMBA 3 AXI
+	  Interconnect (so called AXI Main Interconnect) routing IO requests
+	  from one SoC block to another. This driver provides a way to detect
+	  any bus protocol errors and device not responding situations by
+	  means of an embedded on top of the interconnect errors handler
+	  block (EHB). AXI Interconnect QoS arbitration tuning is currently
+	  unsupported.
+
 config MOXTET
 	tristate "CZ.NIC Turris Mox module configuration bus"
 	depends on SPI_MASTER && OF