doc/release-notes/skiboot-5.10-rc3.rst - skiboot - Git at Google

 .. _skiboot-5.10-rc3:

 skiboot-5.10-rc3
 ================

 skiboot v5.10-rc3 was released on Thursday February 15th 2018. It is the third
 release candidate of skiboot 5.10, which will become the new stable release
 of skiboot following the 5.9 release, first released October 31st 2017.

 skiboot v5.10-rc3 contains all bug fixes as of :ref:`skiboot-5.9.8`
 and :ref:`skiboot-5.4.9` (the currently maintained stable releases). There
 may be more 5.9.x stable releases, it will depend on demand.

 For how the skiboot stable releases work, see :ref:`stable-rules` for details.

 The current plan is to cut the final 5.10 in February, with skiboot 5.10
 being for all POWER8 and POWER9 platforms in op-build v1.21.
 This release will be targeted to early POWER9 systems.

 Over skiboot-5.10-rc2, we have the following changes:

 - vas: Disable VAS/NX-842 on some P9 revisions

   VAS/NX-842 are not functional on some P9 revisions, so disable them
   in hardware and skip creating their device tree nodes.

   Since the intent is to prevent OS from configuring VAS/NX, we remove
   only the platform device nodes but leave the VAS/NX DT nodes under
   xscom (i.e we don't skip add_vas_node() in hdata/spira.c)
 - phb4: Only escalate freezes on MMIO load where necessary

   In order to work around a hardware issue, MMIO load freezes were
   escalated to fences on every chip.  Now that hardware no longer requires
   this, restrict escalation to the chips that actually need it.
 - pflash: Fix makefile dependency issue
 - DT: Add "version" property under ibm, firmware-versions node

   First line of VERSION section in PNOR contains firmware version.
   Use that to add "version" property under firmware versions dt node.

   Sample output:

   .. code-block:: console

      root@xxx2:/proc/device-tree/ibm,firmware-versions# lsprop
      version          "witherspoon-ibm-OP9_v1.19_1.94"

 - npu2: Disable TVT range check when in bypass mode

   On POWER9 the GPUs need to be able to access the MMIO memory space. Therefore
   the TVT range check needs to include the MMIO address space. As any possible
   range check would cover all of memory anyway this patch just disables the TVT
   range check all together when bypassing the TCE tables.
 - hw/npu2: support creset of npu2 devices

   creset calls in the hw procedure that resets the PHY, we don't
   take them out of reset, just put them in reset.

   this fixes a kexec issue.
 - ATTN: Enable flush instruction cache bit in HID register

   In P9, we have to enable "flush the instruction cache" bit along with
   "attn instruction support" bit to trigger attention.
 - capi: Enable channel tag streaming for PHB in CAPP mode

   We re-enable channel tag streaming for PHB in CAPP mode as without it
   PEC was waiting for cresp for each DMA write command before sending a
   new DMA write command on the Powerbus. This resulted in much lower DMA
   write performance than expected.

   The patch updates enable_capi_mode() to remove the masking of
   channel_streaming_en bit in PBCQ Hardware Configuration Register. Also
   does some re-factoring of the code that updates this register to use
   xscom_write_mask instead of xscom_read followed by a xscom_write.
 - core/device.c: Fix dt_find_compatible_node

   dt_find_compatible_node() and dt_find_compatible_node_on_chip() are used to
   find device nodes under a parent/root node with a given compatible
   property.

   dt_next(root, prev) is used to walk the child nodes of the given parent and
   takes two arguments - root contains the parent node to walk whilst prev
   contains the previous child to search from so that it can be used as an
   iterator over all children nodes.

   The first iteration of dt_find_compatible_node(root, prev) calls
   dt_next(root, root) which is not a well defined operation as prev is
   assumed to be child of the root node. The result is that when a node
   contains no children it will start returning the parent nodes siblings
   until it hits the top of the tree at which point a NULL derefence is
   attempted when looking for the root nodes parent.

   Dereferencing NULL can result in undesirable data exceptions during system
   boot and untimely non-hilarious system crashes. dt_next() should not be
   called with prev == root. Instead we add a check to dt_next() such that
   passing prev = NULL will cause it to start iterating from the first child
   node (if any).
 - stb: Put correct label (for skiboot) into container

   Hostboot will expect the label field of the stb header to contain
   "PAYLOAD" for skiboot or it will fail to load and run skiboot.

   The failure looks something like this: ::

      53.40896|ISTEP 20. 1 - host_load_payload
      53.65840|secure|Secureboot Failure plid = 0x90000755, rc = 0x1E07

      53.65881|System shutting down with error status 0x1E07
      53.67547|================================================
      53.67954|Error reported by secure (0x1E00) PLID 0x90000755
      53.67560|  Container's component ID does not match expected component ID
      53.67561|  ModuleId   0x09 SECUREBOOT::MOD_SECURE_VERIFY_COMPONENT
      53.67845|  ReasonCode 0x1e07 SECUREBOOT::RC_ROM_VERIFY
      53.67998|  UserData1   : 0x0000000000000000
      53.67999|  UserData2   : 0x0000000000000000
      53.67999|------------------------------------------------
      53.68000|  Callout type             : Procedure Callout
      53.68000|  Procedure                : EPUB_PRC_HB_CODE
      53.68001|  Priority                 : SRCI_PRIORITY_HIGH
      53.68001|------------------------------------------------
      53.68002|  Callout type             : Procedure Callout
      53.68003|  Procedure                : EPUB_PRC_FW_VERIFICATION_ERR
      53.68003|  Priority                 : SRCI_PRIORITY_HIGH
      53.68004|------------------------------------------------
 - hw/occ: Fix fast-reboot crash in P8 platforms.

   commit 85a1de35cbe4 ("fast-boot: occ: Re-parse the pstate table during fast-boot" )
   breaks the fast-reboot on P8 platforms while reiniting the OCC pstates. On P8
   platforms OPAL adds additional two properties #address-cells and #size-cells
   under ibm,opal/power-mgmt/ DT node. While in fast-reboot same properties adding
   back to the same node results in Duplicate properties and hence fast-reboot fails
   with below traces. ::

     [  541.410373292,5] OCC: All Chip Rdy after 0 ms
     [  541.410488745,3] Duplicate property "#address-cells" in node /ibm,opal/power-mgt
     [  541.410694290,0] Aborting!
     CPU 0058 Backtrace:
      S: 0000000031d639d0 R: 000000003001367c   .backtrace+0x48
      S: 0000000031d63a60 R: 000000003001a03c   ._abort+0x4c
      S: 0000000031d63ae0 R: 00000000300267d8   .new_property+0xd8
      S: 0000000031d63b70 R: 0000000030026a28   .__dt_add_property_cells+0x30
      S: 0000000031d63c10 R: 000000003003ea3c   .occ_pstates_init+0x984
      S: 0000000031d63d90 R: 00000000300142d8   .load_and_boot_kernel+0x86c
      S: 0000000031d63e70 R: 000000003002586c   .fast_reboot_entry+0x358
      S: 0000000031d63f00 R: 00000000300029f4   fast_reset_entry+0x2c

   This patch fixes this issue by removing these two properties on P8 while doing
   OCC pstates re-init in fast-reboot code path.
	.. _skiboot-5.10-rc3:

	skiboot-5.10-rc3
	================

	skiboot v5.10-rc3 was released on Thursday February 15th 2018. It is the third
	release candidate of skiboot 5.10, which will become the new stable release
	of skiboot following the 5.9 release, first released October 31st 2017.

	skiboot v5.10-rc3 contains all bug fixes as of :ref:`skiboot-5.9.8`
	and :ref:`skiboot-5.4.9` (the currently maintained stable releases). There
	may be more 5.9.x stable releases, it will depend on demand.

	For how the skiboot stable releases work, see :ref:`stable-rules` for details.

	The current plan is to cut the final 5.10 in February, with skiboot 5.10
	being for all POWER8 and POWER9 platforms in op-build v1.21.
	This release will be targeted to early POWER9 systems.

	Over skiboot-5.10-rc2, we have the following changes:

	- vas: Disable VAS/NX-842 on some P9 revisions

	VAS/NX-842 are not functional on some P9 revisions, so disable them
	in hardware and skip creating their device tree nodes.

	Since the intent is to prevent OS from configuring VAS/NX, we remove
	only the platform device nodes but leave the VAS/NX DT nodes under
	xscom (i.e we don't skip add_vas_node() in hdata/spira.c)
	- phb4: Only escalate freezes on MMIO load where necessary

	In order to work around a hardware issue, MMIO load freezes were
	escalated to fences on every chip. Now that hardware no longer requires
	this, restrict escalation to the chips that actually need it.
	- pflash: Fix makefile dependency issue
	- DT: Add "version" property under ibm, firmware-versions node

	First line of VERSION section in PNOR contains firmware version.
	Use that to add "version" property under firmware versions dt node.

	Sample output:

	.. code-block:: console

	root@xxx2:/proc/device-tree/ibm,firmware-versions# lsprop
	version "witherspoon-ibm-OP9_v1.19_1.94"

	- npu2: Disable TVT range check when in bypass mode

	On POWER9 the GPUs need to be able to access the MMIO memory space. Therefore
	the TVT range check needs to include the MMIO address space. As any possible
	range check would cover all of memory anyway this patch just disables the TVT
	range check all together when bypassing the TCE tables.
	- hw/npu2: support creset of npu2 devices

	creset calls in the hw procedure that resets the PHY, we don't
	take them out of reset, just put them in reset.

	this fixes a kexec issue.
	- ATTN: Enable flush instruction cache bit in HID register

	In P9, we have to enable "flush the instruction cache" bit along with
	"attn instruction support" bit to trigger attention.
	- capi: Enable channel tag streaming for PHB in CAPP mode

	We re-enable channel tag streaming for PHB in CAPP mode as without it
	PEC was waiting for cresp for each DMA write command before sending a
	new DMA write command on the Powerbus. This resulted in much lower DMA
	write performance than expected.

	The patch updates enable_capi_mode() to remove the masking of
	channel_streaming_en bit in PBCQ Hardware Configuration Register. Also
	does some re-factoring of the code that updates this register to use
	xscom_write_mask instead of xscom_read followed by a xscom_write.
	- core/device.c: Fix dt_find_compatible_node

	dt_find_compatible_node() and dt_find_compatible_node_on_chip() are used to
	find device nodes under a parent/root node with a given compatible
	property.

	dt_next(root, prev) is used to walk the child nodes of the given parent and
	takes two arguments - root contains the parent node to walk whilst prev
	contains the previous child to search from so that it can be used as an
	iterator over all children nodes.

	The first iteration of dt_find_compatible_node(root, prev) calls
	dt_next(root, root) which is not a well defined operation as prev is
	assumed to be child of the root node. The result is that when a node
	contains no children it will start returning the parent nodes siblings
	until it hits the top of the tree at which point a NULL derefence is
	attempted when looking for the root nodes parent.

	Dereferencing NULL can result in undesirable data exceptions during system
	boot and untimely non-hilarious system crashes. dt_next() should not be
	called with prev == root. Instead we add a check to dt_next() such that
	passing prev = NULL will cause it to start iterating from the first child
	node (if any).
	- stb: Put correct label (for skiboot) into container

	Hostboot will expect the label field of the stb header to contain
	"PAYLOAD" for skiboot or it will fail to load and run skiboot.

	The failure looks something like this: ::

	53.40896\|ISTEP 20. 1 - host_load_payload
	53.65840\|secure\|Secureboot Failure plid = 0x90000755, rc = 0x1E07

	53.65881\|System shutting down with error status 0x1E07
	53.67547\|================================================
	53.67954\|Error reported by secure (0x1E00) PLID 0x90000755
	53.67560\| Container's component ID does not match expected component ID
	53.67561\| ModuleId 0x09 SECUREBOOT::MOD_SECURE_VERIFY_COMPONENT
	53.67845\| ReasonCode 0x1e07 SECUREBOOT::RC_ROM_VERIFY
	53.67998\| UserData1 : 0x0000000000000000
	53.67999\| UserData2 : 0x0000000000000000
	53.67999\|------------------------------------------------
	53.68000\| Callout type : Procedure Callout
	53.68000\| Procedure : EPUB_PRC_HB_CODE
	53.68001\| Priority : SRCI_PRIORITY_HIGH
	53.68001\|------------------------------------------------
	53.68002\| Callout type : Procedure Callout
	53.68003\| Procedure : EPUB_PRC_FW_VERIFICATION_ERR
	53.68003\| Priority : SRCI_PRIORITY_HIGH
	53.68004\|------------------------------------------------
	- hw/occ: Fix fast-reboot crash in P8 platforms.

	commit 85a1de35cbe4 ("fast-boot: occ: Re-parse the pstate table during fast-boot" )
	breaks the fast-reboot on P8 platforms while reiniting the OCC pstates. On P8
	platforms OPAL adds additional two properties #address-cells and #size-cells
	under ibm,opal/power-mgmt/ DT node. While in fast-reboot same properties adding
	back to the same node results in Duplicate properties and hence fast-reboot fails
	with below traces. ::

	[ 541.410373292,5] OCC: All Chip Rdy after 0 ms
	[ 541.410488745,3] Duplicate property "#address-cells" in node /ibm,opal/power-mgt
	[ 541.410694290,0] Aborting!
	CPU 0058 Backtrace:
	S: 0000000031d639d0 R: 000000003001367c .backtrace+0x48
	S: 0000000031d63a60 R: 000000003001a03c ._abort+0x4c
	S: 0000000031d63ae0 R: 00000000300267d8 .new_property+0xd8
	S: 0000000031d63b70 R: 0000000030026a28 .__dt_add_property_cells+0x30
	S: 0000000031d63c10 R: 000000003003ea3c .occ_pstates_init+0x984
	S: 0000000031d63d90 R: 00000000300142d8 .load_and_boot_kernel+0x86c
	S: 0000000031d63e70 R: 000000003002586c .fast_reboot_entry+0x358
	S: 0000000031d63f00 R: 00000000300029f4 fast_reset_entry+0x2c

	This patch fixes this issue by removing these two properties on P8 while doing
	OCC pstates re-init in fast-reboot code path.