Commit graph

27 commits

Author SHA1 Message Date
Dhinakaran Pandiyan
0bb9c2b27f drm/dp/mst: Sideband message transaction to power up/down nodes
The POWER_DOWN_PHY and POWER_UP_PHY sideband message transactions allow
the source to reqest any node in a mst path or a whole path to be
powered down or up. This allows drivers to target a specific sink in the
MST topology, an improvement over just power managing the imediate
downstream device. Secondly, since the request-reply protocol waits for an
ACK, we can be sure that a downstream sink has enough time to respond to a
power up/down request.

v2: Fix memory leak (Lyude)
Cc: Lyude <lyude@redhat.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170907001458.9399-1-dhinakaran.pandiyan@intel.com
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
2017-09-11 16:03:57 +03:00
Ville Syrjälä
a4370c7774 drm/atomic: Make private objs proper objects
Make the atomic private object stuff less special by introducing proper
base classes for the object and its state. Drivers can embed these in
their own appropriate objects, after which these things will work
exactly like the plane/crtc/connector states during atomic operations.

v2: Reorder to not depend on drm_dynarray (Daniel)

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> #v1
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170712155102.26276-3-ville.syrjala@linux.intel.com
2017-07-13 19:28:43 +03:00
Pandiyan, Dhinakaran
edb1ed1ab7 drm/dp: Add DP MST helpers to atomically find and release vcpi slots
drm_dp_atomic_find_vcpi_slots() should be called from ->atomic_check() to
check there are sufficient vcpi slots for a mode and to add that to the
state. This should be followed by a call to drm_dp_mst_allocate_vcpi()
in ->atomic_commit() to initialize a struct vcpi for the port.

drm_dp_atomic_release_vcpi_slots() should be called from
->atomic_check() to release a port's vcpi slot allocation from the
state.

Drivers that do not make use of this atomic helper are expected to call
drm_dp_find_vcpi_slots() instead before calling
drm_dp_mst_allocate_vcpi().

v3: drm_dp_atomic_release_vcpi_slots() now needs to know how many slots
    to release as we may not have a valid reference to port.
v2:
Added checks for verifying the port reference is valid
Moved get_mst_topology_state() into the helpers (Daniel)
Changed find_vcpi_slots() to not depend on current allocation

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Harry Wentland <Harry.wentland@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1492753893-3748-4-git-send-email-dhinakaran.pandiyan@intel.com
2017-05-04 15:02:47 +02:00
Pandiyan, Dhinakaran
3f3353b7e1 drm/dp: Introduce MST topology state to track available link bandwidth
Link bandwidth is shared between multiple display streams in DP MST
configurations. The DP MST topology manager structure maintains the
shared link bandwidth for a primary link directly connected to the GPU. For
atomic modesetting drivers, checking if there is sufficient link bandwidth
for a mode needs to be done during the atomic_check phase to avoid failed
modesets. Let's encapsulate the available link bw information in a
private state structure so that bw can be allocated and released atomically
for each of the ports sharing the primary link.

v3: WARN_ON() if connection_mutex is not held (Archit)
v2: Included kernel doc, moved state initialization and switched to
kmemdup() for allocation (Daniel)

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Harry Wentland <Harry.wentland@amd.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1492753893-3748-3-git-send-email-dhinakaran.pandiyan@intel.com
2017-05-04 15:02:46 +02:00
Pandiyan, Dhinakaran
1e797f556c drm/dp: Split drm_dp_mst_allocate_vcpi
drm_dp_mst_allocate_vcpi() apart from setting up the vcpi structure,
also finds if there are enough slots available. This check is a duplicate
of that implemented in drm_dp_mst_find_vcpi_slots(). Let's move this check
out and reuse the existing drm_dp_mst_find_vcpi_slots() function to check
if there are enough vcpi slots before allocating them.

This brings the check to one place. Additionally drivers that will use MST
state tracking for atomic modesets can use the atomic version of
find_vcpi_slots() and reuse drm_dp_mst_allocate_vcpi()

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1489648231-30700-4-git-send-email-dhinakaran.pandiyan@intel.com
2017-03-22 21:47:44 +01:00
Pandiyan, Dhinakaran
feb2c3bc33 drm/dp: Kill unused MST vcpi slot availability tracking
The avail_slots member in the MST topology manager is never updated to
reflect the available vcpi slots. The check is effectively against
total slots, 63. So, let's make that check obvious and remove
avail_slots. While at it, make debug messages more descriptive.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Harry Wentland <Harry.wentland@amd.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1489648231-30700-3-git-send-email-dhinakaran.pandiyan@intel.com
2017-03-22 21:46:41 +01:00
Pandiyan, Dhinakaran
a538d6137d drm/dp: Kill total_pbn and total_slots in struct drm_dp_mst_topology_mgr
The total vcpi time slots is always 63 and does not depend on the link BW,
remove total_slots from MST topology manager struct. The next change is to
remove total_pbn which is hardcoded to 2560. The total PBN that the
topology manager allocates from depends on the link rate and is not a
constant. So, fix this by removing the total_pbn member itself.

Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Harry Wentland <Harry.wentland@amd.com>
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1489648231-30700-2-git-send-email-dhinakaran.pandiyan@intel.com
2017-03-22 21:46:21 +01:00
Daniel Vetter
6806cdf9aa drm/kms-helpers: Use recommened kerneldoc for struct member refs
I just learned that &struct_name.member_name works and looks pretty
even. It doesn't (yet) link to the member directly though, which would
be really good for big structures or vfunc tables (where the
per-member kerneldoc tends to be long).

Also some minor drive-by polish where it makes sense, I read a lot
of docs ...

v2: Comments from Gustavo.

Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Rewiewed-by: Gustavo Padovan <gustavo.padovan@collabora.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170125062657.19270-2-daniel.vetter@ffwll.ch
2017-01-25 16:18:57 +01:00
Dhinakaran Pandiyan
7b0a89a6db drm/dp: Store drm_device in MST topology manager
struct drm_dp_mst_topology_mgr currently stores a pointer to struct dev.
Changing this to instead hold a pointer to drm_device is more useful as it
gives access to DRM structures. This also makes it consistent with other
DRM structures like drm_crtc, drm_connector etc.

Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1485301777-3465-2-git-send-email-dhinakaran.pandiyan@intel.com
2017-01-25 06:01:48 +01:00
Daniel Vetter
132d49d728 drm/dp-mst: Missing kernel doc
Cc: Dave Airlie <airlied@redhat.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1468612088-9721-7-git-send-email-daniel.vetter@ffwll.ch
2016-07-19 10:31:53 +02:00
Daniel Vetter
cb021a3eb6 drm/dp-mst: Remove tx_down_in_progress
Just replicates whether the list is empty or not. Nuke code
to avoid writing docs for it!

Cc: Dave Airlie <airlied@redhat.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1468612088-9721-6-git-send-email-daniel.vetter@ffwll.ch
2016-07-19 10:31:40 +02:00
Hersen Wu
5e93b8208d drm/dp/mst: move GUID storage from mgr, port to only mst branch
Previous implementation does not handle case below: boot up one MST branch
to DP connector of ASIC. After boot up, hot plug 2nd MST branch to DP output
of 1st MST, GUID is not created for 2nd MST branch. When downstream port of
2nd MST branch send upstream request, it fails because 2nd MST branch GUID
is not available.

New Implementation: only create GUID for MST branch and save it within Branch.

Signed-off-by: Hersen Wu <hersenxs.wu@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Cc: stable@vger.kernel.org
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2016-02-05 15:23:49 +10:00
Dave Airlie
28f03607bb Merge tag 'topic/drm-misc-2016-01-17' of git://anongit.freedesktop.org/drm-intel into drm-next
Since your main drm-next pull isn't out of the door yet I figured I might
as well flush out drm-misc instead of delaying for 4.6. It's really just
random stuff all over, biggest thing probably connector_mask tracking from
Maarten.

* tag 'topic/drm-misc-2016-01-17' of git://anongit.freedesktop.org/drm-intel: (24 commits)
  drm/fb_cma_helper: Remove implicit call to disable_unused_functions
  drm/sysfs: use kobj_to_dev()
  drm/i915: Init power domains early in driver load
  drm: Do not set connector->encoder in drivers
  apple-gmux: Add initial documentation
  drm: move MODULE_PARM_DESC to other file
  drm/edid: index CEA/HDMI mode tables using the VIC
  drm/atomic: Remove drm_atomic_connectors_for_crtc.
  drm/i915: Update connector_mask during readout, v2.
  drm: Remove opencoded drm_gem_object_release_handle()
  drm: Do not set outparam on error during GEM handle allocation
  drm/docs: more leftovers from the big vtable documentation pile
  drm/atomic-helper: Reject legacy flips on a disabled pipe
  drm/atomic: add connector mask to drm_crtc_state.
  drm/tegra: Use __drm_atomic_helper_reset_connector for subclassing connector state, v2.
  drm/atomic: Add __drm_atomic_helper_connector_reset, v2.
  drm/i915: Set connector_state->connector using the helper.
  drm: Use a normal idr allocation for the obj->name
  drm: Only bump object-reference count when adding first handle
  drm: Balance error path for GEM handle allocation
  ...
2016-01-18 07:01:16 +10:00
Mykola Lysenko
1f16ee7fa1 drm/dp/mst: always send reply for UP request
We should always send reply for UP request in order
to make downstream device clean-up resources appropriately.

Issue was that reply for UP request was sent only once.

Acked-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Mykola Lysenko <Mykola.Lysenko@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
2016-01-04 12:05:55 -05:00
Julia Lawall
69a0f89c06 drm/dp/mst: constify drm_dp_mst_topology_cbs structures
The drm_dp_mst_topology_cbs structures are never modified, so declare them
as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2016-01-04 08:09:58 +01:00
Libin Yang
ef8f9bea13 dp/mst: add SDP stream support
This adds code to initialise the SDP streams
for a sink in the simplest ordering.

I've no idea how you'd want to control the
ordering at this level, so don't bother
until someone comes up with a use case.

Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com>
Signed-off-by: Libin Yang <libin.yang@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449036584-105393-1-git-send-email-libin.yang@linux.intel.com
2015-12-10 10:00:42 +01:00
Dave Airlie
ae491542cb drm/dp/mst: make mst i2c transfer code more robust.
This zeroes the msg so no random stack data ends up getting
sent, it also limits the function to not accepting > 4
i2c msgs.

Cc: stable@vger.kernel.org
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-10-15 09:06:20 +10:00
Dave Airlie
d9515c5ec1 drm/dp/mst: split connector registration into two parts (v2)
In order to cache the EDID properly for tiled displays, we
need to retrieve it before we register the connector with
userspace, otherwise userspace can call get resources
and try and get the edid before we've even cached it.

This fixes some problems when hotplugging mst monitors,
with X/mutter running. As mutter seems to get 0 modes
for one of the monitors in the tile.

v2: fix warning in radeon
handle tile setting in cached path rather than
get edid path.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-10-02 15:34:41 +10:00
Dave Airlie
6b8eeca65b drm/dp/mst: close deadlock in connector destruction.
I've only seen this once, and I failed to capture the
lockdep backtrace, but I did some investigations.

If we are calling into the MST layer from EDID probing,
we have the mode_config mutex held, if during that EDID
probing, the MST hub goes away, then we can get a deadlock
where the connector destruction function in the driver
tries to retake the mode config mutex.

This offloads connector destruction to a workqueue,
and avoid the subsequenct lock ordering issue.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
2015-06-25 11:57:23 +10:00
Dave Airlie
87f5942d1f drm/dp_mst: add a function to retrieve vcpi slots
radeon requires this to get the slots for later filling
out a table on every transition.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-03-19 12:26:45 -04:00
Dave Airlie
c6a0aed4d4 drm/mst: cached EDID for logical ports (v2)
Logical ports are never going to have EDID changes,
they are used for the internal ports on MST monitors.

We cache the EDIDs from these to save time at MST probe.

v2: drop misplace tile property line, meant for other patch.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-12-09 09:56:47 +10:00
Dave Airlie
4fb2ac6ebe drm: Miscellaneous fixes for v3.19-rc1
This is a small collection of fixes that I've been carrying around for a
 while now. Many of these have been posted and reviewed or acked. The few
 that haven't I deemed too trivial to bother.
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Merge tag 'drm/fixes/for-3.19-rc1' of git://people.freedesktop.org/~tagr/linux into drm-next

drm: Miscellaneous fixes for v3.19-rc1

This is a small collection of fixes that I've been carrying around for a
while now. Many of these have been posted and reviewed or acked. The few
that haven't I deemed too trivial to bother.

* tag 'drm/fixes/for-3.19-rc1' of git://people.freedesktop.org/~tagr/linux:
  video/hdmi: Relicense header under MIT license
  drm/gma500: mdfld: Reuse video/mipi_display.h
  drm: Make drm_mode_create_tv_properties() signature consistent
  drm: Implement drm_get_pci_dev() dummy for !PCI
  drm/prime: Use unsigned type for number of pages
  drm/gem: Fix typo in kerneldoc
  drm: Use const data when creating blob properties
  drm: Use size_t for blob property sizes
2014-11-15 09:37:20 +10:00
Thierry Reding
12e6cecd55 drm: Use const data when creating blob properties
Creating a blob property will always copy the input data so the data
that is passed in can be const.

Signed-off-by: Thierry Reding <treding@nvidia.com>
2014-11-13 10:43:49 +01:00
Dave Airlie
1f9e14baa9 Merge tag 'topic/core-stuff-2014-11-05' of git://anongit.freedesktop.org/drm-intel into drm-next
Just various stuff all over from a bunch of people. Shortlog gives a beter
overview, it's really all misc drm patches.

* tag 'topic/core-stuff-2014-11-05' of git://anongit.freedesktop.org/drm-intel:
  drm/edid: add #defines and helpers for ELD
  drm/dp: Add counters in the drm_dp_aux struct for I2C NACKs and DEFERs
  drm: Remove compiler BUG_ON() test
  drm: Fix DRM_FORCE_ON_DIGITAL use
  drm/gma500: Don't destroy DRM properties in the driver
  drm/i915: Don't destroy DRM properties in the driver
  drm: Add a note to drm_property_create() about property lifetime
  gpu: drm: Fix warning caused by a parameter description in drm_crtc.c
  drm/dp-helper: Move the legacy helpers to gma500
  drm/crtc: Remove duplicated ioctl code
  drm/crtc: Fix two typos
  gpu:drm: Fix typo in Documentation/DocBook/drm.xml
  gpu: drm: drm_dp_mst_topology.c: Fix improper use of strncat
  drm: drm_err: Remove unnecessary __func__ argument
  drm: Implement O_NONBLOCK support on /dev/dri/cardN
2014-11-07 10:58:46 +10:00
Masanari Iida
32197aab04 gpu:drm: Fix typo in Documentation/DocBook/drm.xml
This patch fix spelling typos found in drm.xml.
It is because the file is generated from comments in
source codes, I have to fix the typos within source files.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2014-10-21 10:55:33 +02:00
Dave Airlie
dfda0df342 drm/mst: rework payload table allocation to conform better.
The old code has problems with the Dell MST monitors due to some
assumptions I made that weren't true.

I initially thought the Virtual Channel Payload IDs had to be in
the DPCD table in ascending order, however it appears that assumption
is bogus.

The old code also assumed it was possible to insert a member
into the table and it would move other members up, like it does
when you remove table entries, however reality has shown this
isn't true.

So the new code allocates VCPIs separate from entries in the payload
tracking table, and when we remove an entry from the DPCD table,
I shuffle the tracking payload entries around in the struct.

This appears to make VT switch more robust (still not perfect)
with an MST enabled Dell monitor.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-10-13 14:40:53 +10:00
Dave Airlie
ad7f8a1f9c drm/helper: add Displayport multi-stream helper (v0.6)
This is the initial import of the helper for displayport multistream.

It consists of a topology manager, init/destroy/set mst state

It supports DP 1.2 MST sideband msg protocol handler - via hpd irqs

connector detect and edid retrieval interface.

It supports i2c device over DP 1.2 sideband msg protocol (EDID reads only)

bandwidth manager API via vcpi allocation and payload updating,
along with a helper to check the ACT status.

Objects:
MST topology manager - one per toplevel MST capable GPU port - not sure if this should be higher level again
MST branch unit - one instance per plugged branching unit - one at top of hierarchy - others hanging from ports
MST port - one port per port reported by branching units, can have MST units hanging from them as well.

Changes since initial posting:
a) add a mutex responsbile for the queues, it locks the sideband and msg slots, and msgs to transmit state
b) add worker to handle connection state change events, for MST device chaining and hotplug
c) add a payload spinlock
d) add path sideband msg support
e) fixup enum path resources transmit
f) reduce max dpcd msg to 16, as per DP1.2 spec.
g) separate tx queue kicking from irq processing and move irq acking back to drivers.

Changes since v0.2:
a) reorganise code,
b) drop ACT forcing code
c) add connector naming interface using path property
d) add topology dumper helper
e) proper reference counting and lookup for ports and mstbs.
f) move tx kicking into a workq
g) add aux locking - this should be redone
h) split teardown into two parts
i) start working on documentation on interface.

Changes since v0.3:
a) vc payload locking and tracking fixes
b) add hotplug callback into driver - replaces crazy return 1 scheme
c) txmsg + mst branch device refcount fixes
d) don't bail on mst shutdown if device is gone
e) change irq handler to take all 4 bytes of SINK_COUNT + ESI vectors
f) make DP payload updates timeout longer - observed on docking station redock
g) add more info to debugfs dumper

Changes since v0.4:
a) suspend/resume support
b) more debugging in debugfs

Changes since v0.5:
a) use byte * to avoid unnecessary stack usage
b) fix num_sdp_streams interpretation.
c) init payload state for unplug events
d) remove lenovo dock sink count hack
e) drop aux lock - post rebase
f) call hotplug on port destroy

TODO:
misc features

Reviewed-by: Todd Previte <tprevite@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2014-07-08 11:41:22 +10:00