This series enables uio_pruss on AM33xx and it mostly intended to look
for the proper solution to handling this particular OMAP hwmod which
contains hardware reset lines.
The comment in arch/arm/mach-omap2/omap_hwmod.c:
/*
* If an IP block contains HW reset lines and any of them are
* asserted, we let integration code associated with that
* block handle the enable. We've received very little
* information on what those driver authors need, and until
* detailed information is provided and the driver code is
* posted to the public lists, this is probably the best we
* can do.
*/
is waiting for some information which is at least partially available
with this uio_pruss driver example.
The series has some ifdefery to get uio_pruss to build without the
DaVinci specific sram API, and then some needed DT, pinctrl, and
runtime PM support so I could actually use the driver on AM33xx.
The approach to deal with the hardware reset (for at least the pruss
hwmod) was to add a generic omap property to properly define this
hardware. The implementation simply deasserts any rst lines that
are called out in the property when the omap_device is
instantiated. This is not the right implementation as the sequence is
a bit wrong for pruss since the busy check during the hard reset
will fail, even though it fails in a benign manner. Ideally, we would
want the implementation to observe the ti,deassert-hard-reset property
and use that in omap_hwmod.c:_enable() *after* the module is unidled
and the clocks active. However, this is actually functional for purposes
of getting the uio_pruss driver up and running.
Matt Porter (3):
uio: uio_pruss: port to AM33xx
ARM: omap: add DT support for deasserting hardware reset lines
ARM: dts: AM33xx PRUSS support
.../devicetree/bindings/arm/omap/omap.txt | 2 +
Documentation/devicetree/bindings/uio/pruss.txt | 17 ++++++
.../devicetree/bindings/uio/uio_pruss.txt | 17 ++++++
arch/arm/boot/dts/am335x-bone.dts | 4 ++
arch/arm/boot/dts/am33xx.dtsi | 11 ++++
arch/arm/plat-omap/omap_device.c | 25 +++++++-
drivers/uio/Kconfig | 4 +-
drivers/uio/uio_pruss.c | 63 +++++++++++++++++++-
8 files changed, 138 insertions(+), 5 deletions(-)
create mode 100644 Documentation/devicetree/bindings/uio/pruss.txt
create mode 100644 Documentation/devicetree/bindings/uio/uio_pruss.txt
--
1.7.9.5
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