Add skiboot-5.5.0-rc2 release notes
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
diff --git a/doc/opal-api/opal-npu2-141-142-143.rst b/doc/opal-api/opal-npu2-141-142-143.rst
index 541051c..1d4b33f 100644
--- a/doc/opal-api/opal-npu2-141-142-143.rst
+++ b/doc/opal-api/opal-npu2-141-142-143.rst
@@ -1,3 +1,5 @@
+.. _OPAL_NPU2:
+
OPAL NPU2 calls
================
@@ -21,6 +23,8 @@
The OPAL calls documented here are used to setup/destroy the
appropriate context for a given process on a given NVLink2 device.
+.. _OPAL_NPU_INIT_CONTEXT:
+
OPAL_NPU_INIT_CONTEXT
---------------------
@@ -40,6 +44,8 @@
contexts are available or ``OPAL_UNSUPPORTED`` in the case of
unsupported MSR bits.
+.. _OPAL_NPU_DESTROY_CONTEXT:
+
OPAL_NPU_DESTROY_CONTEXT
------------------------
@@ -51,6 +57,8 @@
Destroys a previously allocated context ID. This may cause further
translation requests from the GPU to fail.
+.. _OPAL_NPU_MAP_LPAR:
+
OPAL_NPU_MAP_LPAR
-----------------
diff --git a/doc/release-notes/skiboot-5.5.0-rc2.rst b/doc/release-notes/skiboot-5.5.0-rc2.rst
new file mode 100644
index 0000000..30cb79b
--- /dev/null
+++ b/doc/release-notes/skiboot-5.5.0-rc2.rst
@@ -0,0 +1,172 @@
+.. _skiboot-5.5.0-rc2:
+
+skiboot-5.5.0-rc2
+=================
+
+skiboot-5.5.0-rc2 was released on Monday April 3rd 2017. It is the second
+release candidate of skiboot 5.5, which will become the new stable release
+of skiboot following the 5.4 release, first released November 11th 2016.
+
+skiboot-5.5.0-rc2 contains all bug fixes as of :ref:`skiboot-5.4.3`
+and :ref:`skiboot-5.1.19` (the currently maintained stable releases).
+
+For how the skiboot stable releases work, see :ref:`stable-rules` for details.
+
+The current plan is to cut the final 5.5.0 by April 8th, with skiboot 5.5.0
+being for all POWER8 and POWER9 platforms in op-build v1.16 (Due April 12th).
+This is a short cycle as this release is mainly targetted towards POWER9
+bringup efforts.
+
+Following skiboot-5.5.0, we will move to a regular six week release cycle,
+similar to op-build, but slightly offset to allow for a short stabilisation
+period. Expected release dates and contents are tracked using GitHub milestone
+and issues: https://github.com/open-power/skiboot/milestones
+
+Over :ref:`skiboot-5.5.0-rc1`, we have the following changes:
+
+NVLINK2
+-------
+
+- Introduce NPU2 support
+
+ NVLink2 is a new feature introduced on POWER9 systems. It is an
+ evolution of of the NVLink1 feature included in POWER8+ systems but
+ adds several new features including support for GPU address
+ translation using the Nest MMU and cache coherence.
+
+ Similar to NVLink1 the functionality is exposed to the OS as a series
+ of virtual PCIe devices. However the actual hardware interfaces are
+ significantly different which limits the amount of common code that
+ can be shared between implementations in the firmware.
+
+ This patch adds basic hardware initialisation and exposure of the
+ virtual NVLink2 PCIe devices to the running OS.
+
+- npu2: Add OPAL calls for nvlink2 address translation services (see :ref:`OPAL_NPU2`)
+
+ Adds three OPAL calls for interacting with NPU2 devices:
+ :ref:`OPAL_NPU_INIT_CONTEXT`, :ref:`OPAL_NPU_DESTROY_CONTEXT` and
+ :ref:`OPAL_NPU_MAP_LPAR`.
+
+ These are used to setup and configure address translation services
+ (ATS) for a process/partition on a given NVLink2 device.
+
+
+POWER9
+------
+- hdata/memory: ignore homer and occ reserved ranges
+
+ We populate these from the HOMER BARs in the PBA directly. There's no
+ need to take the hostboot supplied values so just ignore the
+ corresponding reserved ranges.
+
+- hdata/vpd: Parse the OpenPOWER OPFR record
+
+ Parse the OpenPOWER FRU VPD (OPFR) record on OpenPOWER instead
+ of the VINI records.
+
+- hdata/vpd: Parse additional VINI records
+
+ These records provide hardware version details, CCIN extension information,
+ card type details and hardware characteristics of the FRU
+
+- hdata/cpu: account for p9 shared caches
+
+ On P9 the L2 and L3 caches are shared between pairs of SMT=4 cores.
+ Currently this is not accounted for when creating caches nodes in
+ the device tree. This patch adds additional checking so that a
+ cache node is only created for the first core in the pair and
+ the second core will reference the cache correctly.
+
+- hdata: print backtraces on HDAT errors
+- hdat: ignore zero length reserves
+
+ Hostboot can export reserved regions with a length of zero and these
+ should be ignored rather than being turned into reserved range. While
+ we're here fix a memory leak by moving the "too large" region check
+ to before we allocate space for the label.
+
+- SLW: Add init for power9 power management
+
+ This patch adds new function to init core for power9 power management.
+ SPECIAL_WKUP_* SCOM registers, if set, can hold the cores from going into
+ idle states. Hence, clear PPM_SPECIAL_WKUP_HYP_REG scom register for each
+ core during init. (This init are not required for MAMBO)
+
+
+PCI
+---
+
+- hw/phb3: Adjust ECRC on root port dynamically
+
+ The Samsung NVMe adapter is lost when it's connected to PMC 8546 PCIe
+ switch, until ECRC is disabled on the root port. We found similar issue
+ prevously when Broadcom adapter is connected to same part of PCIe switch
+ and it was fixed by commit 60ce59ccd0e9 ("hw/phb3: Disable ECRC on Broadcom
+ adapter behind PMC switch"). Unfortunately, the commit doesn't fix
+ the Samsung NVMe adapter lost issue.
+
+ This fixes the issues by disable ECRC generation/check on root port
+ when PMC 8546 PCIe switch ports are found. This can be extended for
+ other PCIe switches or endpoints in future: Each PHB maintains the
+ count of PCI devices (PMC 8546 PCIe switch ports currently) which
+ require to disable ECRC on root port. The ECRC functionality is
+ enabled when first PMC 8546 switch port is probed and disabled when
+ last PMC 8546 switch port is destroyed (in PCI hot remove scenario).
+ Except PHB's reinitialization after complete reset, the ECRC on
+ root port is untouched.
+
+- core/pci: Fix lost NVMe adapter behind PMC 8546 switch
+
+ The NVMe adapter in below PCI topology is lost. The root cause is
+ the presence bit on its PCI slot is missed, but the PCIe link has
+ been up. The PCI core doesn't probe the adapter behind the slot,
+ leading to lost NVMe adapter in the particular case.
+
+ - PHB3 root port
+ - PLX switch 8748 (10b5:8748)
+ - PLX swich 9733 (10b5:9733)
+ - PMC 8546 swtich (11f8:8546)
+ - NVMe adapter (1c58:0023)
+
+ This fixes the issue by overriding the PCI slot presence bit with
+ PCIe link state bit.
+- hw/phb4: Locate AER capability position if necessary
+- core/pci: Disable surprise hotplug on root port
+- core/pci: Ignore PCI slot capability on root port
+
+ We are creating PCI slot on root port, where the PCI slot isn't
+ supported from hardware. For this case, we shouldn't read the PCI
+ slot capability from hardware. When bogus data returned from the
+ hardware, we will attempt to the PCI slot's power state or enable
+ surprise hotplug functionality. All of them can't be accomplished
+ without hardware support.
+
+ This leaves the PCI slot's capability list 0 if PCICAP_EXP_CAP_SLOT
+ isn't set in hardware (pcie_cap + 0x2). Otherwise, the PCI slot's
+ capability list is retrieved from hardware (pcie_cap + 0x14).
+
+
+- phb4: Default to PCIe GEN2 on DD1
+
+ Default to PCIe GEN2 link speeds on DD1 for stability.
+
+ Can be overridden using nvram pcie-max-link-speed=4 parameter.
+
+- phb3/4: Set max link speed via nvram
+
+ This adds an nvram parameter pcie-max-link-speed to configure the max
+ speed of the pcie link. This can be set from the petitboot prompt
+ using: ::
+
+ nvram -p ibm,skiboot --update-config pcie-max-link-speed=4
+
+ This takes preference over anything set in the device tree and is
+ global to all PHBs.
+
+Tests
+-----
+
+- Mambo/Qemu boot tests: expect (and fail) on checkstop
+
+ This allows us to fail a lot faster if we checkstop
