| .. _skiboot-6.3.2: |
| |
| ============== |
| skiboot-6.3.2 |
| ============== |
| |
| skiboot 6.3.2 was released on Monday July 1st, 2019. It replaces |
| :ref:`skiboot-6.3.1` as the current stable release in the 6.3.x series. |
| |
| It is recommended that 6.3.2 be used instead of 6.3.1 version due to the |
| bug fixes it contains. |
| |
| Bug fixes included in this release are: |
| |
| - npu2: Purge cache when resetting a GPU |
| |
| After putting all a GPU's links in reset, do a cache purge in case we |
| have CPU cache lines belonging to the now-unaccessible GPU memory. |
| |
| - npu2: Reset NVLinks when resetting a GPU |
| |
| Resetting a V100 GPU brings its NVLinks down and if an NPU tries using |
| those, an HMI occurs. We were lucky not to observe this as the bare metal |
| does not normally reset a GPU and when passed through, GPUs are usually |
| before NPUs in QEMU command line or Libvirt XML and because of that NPUs |
| are naturally reset first. However simple change of the device order |
| brings HMIs. |
| |
| This defines a bus control filter for a PCI slot with a GPU with NVLinks |
| so when the host system issues secondary bus reset to the slot, it resets |
| associated NVLinks. |
| |
| - hw/phb4: Assert Link Disable bit after ETU init |
| |
| The cursed RAID card in ozrom1 has a bug where it ignores PERST being |
| asserted. The PCIe Base spec is a little vague about what happens |
| while PERST is asserted, but it does clearly specify that when |
| PERST is de-asserted the Link Training and Status State Machine |
| (LTSSM) of a device should return to the initial state (Detect) |
| defined in the spec and the link training process should restart. |
| |
| This bug was worked around in 9078f8268922 ("phb4: Delay training till |
| after PERST is deasserted") by setting the link disable bit at the |
| start of the FRESET process and clearing it after PERST was |
| de-asserted. Although this fixed the bug, the patch offered no |
| explaination of why the fix worked. |
| |
| In b8b4c79d4419 ("hw/phb4: Factor out PERST control") the link disable |
| workaround was moved into phb4_assert_perst(). This is called |
| always in the CRESET case, but a following patch resulted in |
| assert_perst() not being called if phb4_freset() was entered following a |
| CRESET since p->skip_perst was set in the CRESET handler. This is bad |
| since a side-effect of the CRESET is that the Link Disable bit is |
| cleared. |
| |
| This, combined with the RAID card ignoring PERST results in the PCIe |
| link being trained by the PHB while we're waiting out the 100ms |
| ETU reset time. If we hack skiboot to print a DLP trace after returning |
| from phb4_hw_init() we get: :: |
| |
| PHB#0001[0:1]: Initialization complete |
| PHB#0001[0:1]: TRACE:0x0000102101000000 0ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000001101000000 23ms GEN1:x16:detect |
| PHB#0001[0:1]: TRACE:0x0000102101000000 23ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000183101000000 29ms training GEN1:x16:config |
| PHB#0001[0:1]: TRACE:0x00001c5881000000 30ms training GEN1:x08:recovery |
| PHB#0001[0:1]: TRACE:0x00001c5883000000 30ms training GEN3:x08:recovery |
| PHB#0001[0:1]: TRACE:0x0000144883000000 33ms presence GEN3:x08:L0 |
| PHB#0001[0:1]: TRACE:0x0000154883000000 33ms trained GEN3:x08:L0 |
| PHB#0001[0:1]: CRESET: wait_time = 100 |
| PHB#0001[0:1]: FRESET: Starts |
| PHB#0001[0:1]: FRESET: Prepare for link down |
| PHB#0001[0:1]: FRESET: Assert skipped |
| PHB#0001[0:1]: FRESET: Deassert |
| PHB#0001[0:1]: TRACE:0x0000154883000000 0ms trained GEN3:x08:L0 |
| PHB#0001[0:1]: TRACE: Reached target state |
| PHB#0001[0:1]: LINK: Start polling |
| PHB#0001[0:1]: LINK: Electrical link detected |
| PHB#0001[0:1]: LINK: Link is up |
| PHB#0001[0:1]: LINK: Went down waiting for stabilty |
| PHB#0001[0:1]: LINK: DLP train control: 0x0000105101000000 |
| PHB#0001[0:1]: CRESET: Starts |
| |
| What has happened here is that the link is trained to 8x Gen3 33ms after |
| we return from phb4_init_hw(), and before we've waitined to 100ms |
| that we normally wait after re-initialising the ETU. When we "deassert" |
| PERST later on in the FRESET handler the link in L0 (normal) state. At |
| this point we try to read from the Vendor/Device ID register to verify |
| that the link is stable and immediately get a PHB fence due to a PCIe |
| Completion Timeout. Skiboot attempts to recover by doing another CRESET, |
| but this will encounter the same issue. |
| |
| This patch fixes the problem by setting the Link Disable bit (by calling |
| phb4_assert_perst()) immediately after we return from phb4_init_hw(). |
| This prevents the link from being trained while PERST is asserted which |
| seems to avoid the Completion Timeout. With the patch applied we get: :: |
| |
| PHB#0001[0:1]: Initialization complete |
| PHB#0001[0:1]: TRACE:0x0000102101000000 0ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000001101000000 23ms GEN1:x16:detect |
| PHB#0001[0:1]: TRACE:0x0000102101000000 23ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000909101000000 29ms presence GEN1:x16:disabled |
| PHB#0001[0:1]: CRESET: wait_time = 100 |
| PHB#0001[0:1]: FRESET: Starts |
| PHB#0001[0:1]: FRESET: Prepare for link down |
| PHB#0001[0:1]: FRESET: Assert skipped |
| PHB#0001[0:1]: FRESET: Deassert |
| PHB#0001[0:1]: TRACE:0x0000001101000000 0ms GEN1:x16:detect |
| PHB#0001[0:1]: TRACE:0x0000102101000000 0ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000001101000000 24ms GEN1:x16:detect |
| PHB#0001[0:1]: TRACE:0x0000102101000000 36ms presence GEN1:x16:polling |
| PHB#0001[0:1]: TRACE:0x0000183101000000 97ms training GEN1:x16:config |
| PHB#0001[0:1]: TRACE:0x00001c5881000000 97ms training GEN1:x08:recovery |
| PHB#0001[0:1]: TRACE:0x00001c5883000000 97ms training GEN3:x08:recovery |
| PHB#0001[0:1]: TRACE:0x0000144883000000 99ms presence GEN3:x08:L0 |
| PHB#0001[0:1]: TRACE: Reached target state |
| PHB#0001[0:1]: LINK: Start polling |
| PHB#0001[0:1]: LINK: Electrical link detected |
| PHB#0001[0:1]: LINK: Link is up |
| PHB#0001[0:1]: LINK: Link is stable |
| PHB#0001[0:1]: LINK: Card [9005:028c] Optimal Retry:disabled |
| PHB#0001[0:1]: LINK: Speed Train:GEN3 PHB:GEN4 DEV:GEN3 |
| PHB#0001[0:1]: LINK: Width Train:x08 PHB:x08 DEV:x08 |
| PHB#0001[0:1]: LINK: RX Errors Now:0 Max:8 Lane:0x0000 |
| |
| - npu2: Reset PID wildcard and refcounter when mapped to LPID |
| |
| Since 105d80f85b "npu2: Use unfiltered mode in XTS tables" we do not |
| register every PID in the XTS table so the table has one entry per LPID. |
| Then we added a reference counter to keep track of the entry use when |
| switching GPU between the host and guest systems (the "Fixes:" tag below). |
| |
| The POWERNV platform setup creates such entries and references them |
| at the boot time when initializing IOMMUs and only removes it when |
| a GPU is passed through to a guest. This creates a problem as POWERNV |
| boots via kexec and no defererencing happens; the XTS table state remains |
| undefined. So when the host kernel boots, skiboot thinks there are valid |
| XTS entries and does not update the XTS table which breaks ATS. |
| |
| This adds the reference counter and the XTS entry reset when a GPU is |
| assigned to LPID and we cannot rely on the kernel to clean that up. |
| |
| - hw/phb4: Use read/write_reg in assert_perst |
| |
| While the PHB is fenced we can't use the MMIO interface to access PHB |
| registers. While processing a complete reset we inject a PHB fence to |
| isolate the PHB from the rest of the system because the PHB won't |
| respond to MMIOs from the rest of the system while being reset. |
| |
| We assert PERST after the fence has been erected which requires us to |
| use the XSCOM indirect interface to access the PHB registers rather than |
| the MMIO interface. Previously we did that when asserting PERST in the |
| CRESET path. However in b8b4c79d4419 ("hw/phb4: Factor out PERST |
| control"). This was re-written to use the raw in_be64() accessor. This |
| means that CRESET would not be asserted in the reset path. On some |
| Mellanox cards this would prevent them from re-loading their firmware |
| when the system was fast-reset. |
| |
| This patch fixes the problem by replacing the raw {in|out}_be64() |
| accessors with the phb4_{read|write}_reg() functions. |
| |
| - opal-prd: Fix prd message size issue |
| |
| If prd messages size is insufficient then read_prd_msg() call fails with |
| below error. And caller is not reallocating sufficient buffer. Also its |
| hard to guess the size. |
| |
| sample log:: |
| |
| Mar 28 03:31:43 zz24p1 opal-prd: FW: error reading from firmware: alloc 32 rc -1: Invalid argument |
| Mar 28 03:31:43 zz24p1 opal-prd: FW: error reading from firmware: alloc 32 rc -1: Invalid argument |
| Mar 28 03:31:43 zz24p1 opal-prd: FW: error reading from firmware: alloc 32 rc -1: Invalid argument |
| |
| Lets use opal-msg-size device tree property to allocate memory |
| for prd message. |
| |
| - npu2: Fix clearing the FIR bits |
| |
| FIR registers are SCOM-only so they cannot be accesses with the indirect |
| write, and yet we use SCOM-based addresses for these; fix this. |
| |
| - opal-gard: Account for ECC size when clearing partition |
| |
| When 'opal-gard clear all' is run, it works by erasing the GUARD then |
| using blockevel_smart_write() to write nothing to the partition. This |
| second write call is needed because we rely on libflash to set the ECC |
| bits appropriately when the partition contained ECCed data. |
| |
| The API for this is a little odd with the caller specifying how much |
| actual data to write, and libflash writing size + size/8 bytes |
| since there is one additional ECC byte for every eight bytes of data. |
| |
| We currently do not account for the extra space consumed by the ECC data |
| in reset_partition() which is used to handle the 'clear all' command. |
| Which results in the paritition following the GUARD partition being |
| partially overwritten when the command is used. This patch fixes the |
| problem by reducing the length we would normally write by the number |
| of ECC bytes required. |
| |
| - nvram: Flag dangerous NVRAM options |
| |
| Most nvram options used by skiboot are just for debug or testing for |
| regressions. They should never be used long term. |
| |
| We've hit a number of issues in testing and the field where nvram |
| options have been set "temporarily" but haven't been properly cleared |
| after, resulting in crashes or real bugs being masked. |
| |
| This patch marks most nvram options used by skiboot as dangerous and |
| prints a chicken to remind users of the problem. |
| |
| - devicetree: Don't set path to dtc in makefile |
| |
| By setting the path we fail to build under buildroot which has it's own |
| set of host tools in PATH, but not at /usr/bin. |
| |
| Keep the variable so it can be set if need be but default to whatever |
| 'dtc' is in the users path. |
