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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-01-20 14:01:31 -0300
commitb4b7ff4b08e691656c9d77c758fc355833128ac0 (patch)
tree82fcb00e6b918026dc9f2d1f05ed8eee83874cc0 /Documentation/arm/keystone
parent35acfa0fc609f2a2cd95cef4a6a9c3a5c38f1778 (diff)
Linux-libre 4.4-gnupck-4.4-gnu
Diffstat (limited to 'Documentation/arm/keystone')
-rw-r--r--Documentation/arm/keystone/Overview.txt18
-rw-r--r--Documentation/arm/keystone/knav-qmss.txt35
2 files changed, 35 insertions, 18 deletions
diff --git a/Documentation/arm/keystone/Overview.txt b/Documentation/arm/keystone/Overview.txt
index f17bc4c9d..400c0c270 100644
--- a/Documentation/arm/keystone/Overview.txt
+++ b/Documentation/arm/keystone/Overview.txt
@@ -49,24 +49,6 @@ specified through DTS. Following are the DTS used:-
The device tree documentation for the keystone machines are located at
Documentation/devicetree/bindings/arm/keystone/keystone.txt
-Known issues & workaround
--------------------------
-
-Some of the device drivers used on keystone are re-used from that from
-DaVinci and other TI SoCs. These device drivers may use clock APIs directly.
-Some of the keystone specific drivers such as netcp uses run time power
-management API instead to enable clock. As this API has limitations on
-keystone, following workaround is needed to boot Linux.
-
- Add 'clk_ignore_unused' to the bootargs env variable in u-boot. Otherwise
- clock frameworks will try to disable clocks that are unused and disable
- the hardware. This is because netcp related power domain and clock
- domains are enabled in u-boot as run time power management API currently
- doesn't enable clocks for netcp due to a limitation. This workaround is
- expected to be removed in the future when proper API support becomes
- available. Until then, this work around is needed.
-
-
Document Author
---------------
Murali Karicheri <m-karicheri2@ti.com>
diff --git a/Documentation/arm/keystone/knav-qmss.txt b/Documentation/arm/keystone/knav-qmss.txt
new file mode 100644
index 000000000..d119e0236
--- /dev/null
+++ b/Documentation/arm/keystone/knav-qmss.txt
@@ -0,0 +1,35 @@
+* Texas Instruments Keystone Navigator Queue Management SubSystem driver
+
+Driver source code path
+ drivers/soc/ti/knav_qmss.c
+ drivers/soc/ti/knav_qmss_acc.c
+
+The QMSS (Queue Manager Sub System) found on Keystone SOCs is one of
+the main hardware sub system which forms the backbone of the Keystone
+multi-core Navigator. QMSS consist of queue managers, packed-data structure
+processors(PDSP), linking RAM, descriptor pools and infrastructure
+Packet DMA.
+The Queue Manager is a hardware module that is responsible for accelerating
+management of the packet queues. Packets are queued/de-queued by writing or
+reading descriptor address to a particular memory mapped location. The PDSPs
+perform QMSS related functions like accumulation, QoS, or event management.
+Linking RAM registers are used to link the descriptors which are stored in
+descriptor RAM. Descriptor RAM is configurable as internal or external memory.
+The QMSS driver manages the PDSP setups, linking RAM regions,
+queue pool management (allocation, push, pop and notify) and descriptor
+pool management.
+
+knav qmss driver provides a set of APIs to drivers to open/close qmss queues,
+allocate descriptor pools, map the descriptors, push/pop to queues etc. For
+details of the available APIs, please refers to include/linux/soc/ti/knav_qmss.h
+
+DT documentation is available at
+Documentation/devicetree/bindings/soc/ti/keystone-navigator-qmss.txt
+
+Accumulator QMSS queues using PDSP firmware
+============================================
+The QMSS PDSP firmware support accumulator channel that can monitor a single
+queue or multiple contiguous queues. drivers/soc/ti/knav_qmss_acc.c is the
+driver that interface with the accumulator PDSP. This configures
+accumulator channels defined in DTS (example in DT documentation) to monitor
+1 or 32 queues per channel. /*(DEBLOBBED)*/