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 skiboot-5.9.8 and 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 Skiboot stable tree rules and releases 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:

  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.