bus: add Broadcom GISB bus arbiter timeout/error handler

This patch adds support for the Broadcom GISB arbiter bus timeout/error
handler. GISB is a proprietary bus used by Broadcom Set Top Box
System-on-a-chip devices (BCM7xxx) which allows multiple masters and
clients to be interfaced with each other.

The bus arbiter offers support for generating two interrupts towards the
host CPU, thus allowing us to "catch" clock gated masters, or masters
being volontarily blocked for powersaving purposes, or do general system
troubleshooting.

We also register a hook with the ARM fault exception handling to allow
printing a more informative message than "imprecise external abort at
0x00000000" for instance.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 552373c4e362..d40d155f4234 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -4,6 +4,14 @@
 
 menu "Bus devices"
 
+config BRCMSTB_GISB_ARB
+        bool "Broadcom STB GISB bus arbiter"
+        depends on ARM
+        help
+          Driver for the Broadcom Set Top Box System-on-a-chip internal bus
+          arbiter. This driver provides timeout and target abort error handling
+          and internal bus master decoding.
+
 config IMX_WEIM
         bool "Freescale EIM DRIVER"
         depends on ARCH_MXC