kernel/drivers/pci/controller/vmd.c, branch linux-6.5.y

PCI: vmd: Correct PCI Header Type Register's multi-function check

2023-11-20T10:57:08Z

[ Upstream commit 5827e17d0555b566c32044b0632b46f9f95054fa ] vmd_domain_reset() attempts to find whether the device may contain multiple functions by checking 0x80 (Multi-Function Device), however, the hdr_type variable has already been masked with PCI_HEADER_TYPE_MASK so the check can never true. To fix the issue, don't mask the read with PCI_HEADER_TYPE_MASK. Fixes: 6aab5622296b ("PCI: vmd: Clean up domain before enumeration") Link: https://lore.kernel.org/r/20231003125300.5541-2-ilpo.jarvinen@linux.intel.com Signed-off-by: Ilpo Järvinen Signed-off-by: Bjorn Helgaas Cc: Nirmal Patel Signed-off-by: Sasha Levin

PCI: vmd: Disable bridge window for domain reset

2023-09-23T09:14:27Z

[ Upstream commit f73eedc90bf73d48e8368e6b0b4ad76a7fffaef7 ] During domain reset process vmd_domain_reset() clears PCI configuration space of VMD root ports. But certain platform has observed following errors and failed to boot. ... DMAR: VT-d detected Invalidation Queue Error: Reason f DMAR: VT-d detected Invalidation Time-out Error: SID ffff DMAR: VT-d detected Invalidation Completion Error: SID ffff DMAR: QI HEAD: UNKNOWN qw0 = 0x0, qw1 = 0x0 DMAR: QI PRIOR: UNKNOWN qw0 = 0x0, qw1 = 0x0 DMAR: Invalidation Time-out Error (ITE) cleared The root cause is that memset_io() clears prefetchable memory base/limit registers and prefetchable base/limit 32 bits registers sequentially. This seems to be enabling prefetchable memory if the device disabled prefetchable memory originally. Here is an example (before memset_io()): PCI configuration space for 10000:00:00.0: 86 80 30 20 06 00 10 00 04 00 04 06 00 00 01 00 00 00 00 00 00 00 00 00 00 01 01 00 00 00 00 20 00 00 00 00 01 00 01 00 ff ff ff ff 75 05 00 00 ... So, prefetchable memory is ffffffff00000000-575000fffff, which is disabled. When memset_io() clears prefetchable base 32 bits register, the prefetchable memory becomes 0000000000000000-575000fffff, which is enabled and incorrect. Here is the quote from section 7.5.1.3.9 of PCI Express Base 6.0 spec: The Prefetchable Memory Limit register must be programmed to a smaller value than the Prefetchable Memory Base register if there is no prefetchable memory on the secondary side of the bridge. This is believed to be the reason for the failure and in addition the sequence of operation in vmd_domain_reset() is not following the PCIe specs. Disable the bridge window by executing a sequence of operations borrowed from pci_disable_bridge_window() and pci_setup_bridge_io(), that comply with the PCI specifications. Link: https://lore.kernel.org/r/20230810215029.1177379-1-nirmal.patel@linux.intel.com Signed-off-by: Nirmal Patel Signed-off-by: Lorenzo Pieralisi Signed-off-by: Sasha Levin

PCI: vmd: Fix uninitialized variable usage in vmd_enable_domain()

2023-06-24T16:09:16Z

The ret variable in the vmd_enable_domain() function was used uninitialized when printing a warning message upon failure of the pci_reset_bus() function. Thus, fix the issue by assigning ret with the value returned from pci_reset_bus() before referencing it in the warning message. This was detected by Smatch: drivers/pci/controller/vmd.c:931 vmd_enable_domain() error: uninitialized symbol 'ret'. [kwilczynski: drop the second patch from the series, add missing reported by tag, commit log] Fixes: 0a584655ef89 ("PCI: vmd: Fix secondary bus reset for Intel bridges") Link: https://lore.kernel.org/all/202305270219.B96IiIfv-lkp@intel.com Link: https://lore.kernel.org/linux-pci/20230420094332.1507900-2-korantwork@gmail.com Reported-by: kernel test robot Reported-by: Dan Carpenter Signed-off-by: Xinghui Li Signed-off-by: Krzysztof Wilczyński Reviewed-by: Nirmal Patel

PCI: vmd: Reset VMD config register between soft reboots

2023-05-08T07:17:13Z

VMD driver can disable or enable MSI remapping by changing VMCONFIG_MSI_REMAP register. This register needs to be set to the default value during soft reboots. Drives failed to enumerate when Windows boots after performing a soft reboot from Linux. Windows doesn't support MSI remapping disable feature and stale register value hinders Windows VMD driver initialization process. Adding vmd_shutdown function to make sure to set the VMCONFIG register to the default value. Link: https://lore.kernel.org/r/20230224202811.644370-1-nirmal.patel@linux.intel.com Fixes: ee81ee84f873 ("PCI: vmd: Disable MSI-X remapping when possible") Signed-off-by: Nirmal Patel Signed-off-by: Lorenzo Pieralisi Reviewed-by: Jon Derrick

PCI: vmd: Add quirk to configure PCIe ASPM and LTR

2023-02-02T15:02:40Z

PCIe ports reserved for VMD use are not visible to BIOS and therefore not configured to enable PCIe ASPM or LTR values (which BIOS will configure if they are not set). Lack of this programming results in high power consumption on laptops as reported in bugzilla. For affected products use pci_enable_link_state to set the allowed link states for devices on the root ports. Also set the LTR value to the maximum value needed for the SoC. This is a workaround for products from Rocket Lake through Alder Lake. Raptor Lake, the latest product at this time, has already implemented LTR configuring in BIOS. Future products will move ASPM configuration back to BIOS as well. As this solution is intended for laptops, support is not added for hotplug or for devices downstream of a switch on the root port. Link: https://bugzilla.kernel.org/show_bug.cgi?id=212355 Link: https://bugzilla.kernel.org/show_bug.cgi?id=215063 Link: https://bugzilla.kernel.org/show_bug.cgi?id=213717 Link: https://lore.kernel.org/r/20230120031522.2304439-5-david.e.box@linux.intel.com Signed-off-by: Michael Bottini Signed-off-by: David E. Box Signed-off-by: Lorenzo Pieralisi Reviewed-by: Jon Derrick Reviewed-by: Nirmal Patel Reviewed-by: Kuppuswamy Sathyanarayanan

PCI: vmd: Create feature grouping for client products

2023-02-02T15:02:34Z

Simplify the device ID list by creating a grouping of features shared by client products. Suggested-by: Jon Derrick Link: https://lore.kernel.org/r/20230120031522.2304439-4-david.e.box@linux.intel.com Signed-off-by: David E. Box Signed-off-by: Lorenzo Pieralisi Reviewed-by: Kuppuswamy Sathyanarayanan

PCI: vmd: Use PCI_VDEVICE in device list

2023-02-02T15:01:57Z

Use PCI_VDEVICE to simplify the device table. Link: https://lore.kernel.org/r/20230120031522.2304439-3-david.e.box@linux.intel.com Signed-off-by: David E. Box Signed-off-by: Lorenzo Pieralisi Reviewed-by: Jon Derrick Reviewed-by: Nirmal Patel Reviewed-by: Kuppuswamy Sathyanarayanan

PCI: vmd: Fix secondary bus reset for Intel bridges

2022-12-06T10:45:25Z

The reset was never applied in the current implementation because Intel Bridges owned by VMD are parentless. Internally, pci_reset_bus() applies a reset to the parent of the PCI device supplied as argument, but in this case it failed because there wasn't a parent. In more detail, this change allows the VMD driver to enumerate NVMe devices in pass-through configurations when guest reboots are performed. There was an attempted to fix this, but later we discovered that the code inside pci_reset_bus() wasn’t triggering secondary bus resets. Therefore, we updated the parameters passed to it, and now NVMe SSDs attached to VMD bridges are properly enumerated in VT-d pass-through scenarios. Link: https://lore.kernel.org/r/20221206001637.4744-1-francisco.munoz.ruiz@linux.intel.com Fixes: 6aab5622296b ("PCI: vmd: Clean up domain before enumeration") Signed-off-by: Francisco Munoz Signed-off-by: Lorenzo Pieralisi Reviewed-by: Nirmal Patel Reviewed-by: Jonathan Derrick

PCI: vmd: Disable MSI remapping after suspend

2022-11-11T11:00:26Z

MSI remapping is disabled by VMD driver for Intel's Icelake and newer systems in order to improve performance by setting VMCONFIG_MSI_REMAP. By design VMCONFIG_MSI_REMAP register is cleared by firmware during boot. The same register gets cleared when system is put in S3 power state. VMD driver needs to set this register again in order to avoid interrupt issues with devices behind VMD if MSI remapping was disabled before. Link: https://lore.kernel.org/r/20221109142652.450998-1-nirmal.patel@linux.intel.com Fixes: ee81ee84f873 ("PCI: vmd: Disable MSI-X remapping when possible") Signed-off-by: Nirmal Patel Signed-off-by: Lorenzo Pieralisi Reviewed-by: Francisco Munoz

PCI: vmd: Add DID 8086:7D0B and 8086:AD0B for Intel MTL SKUs

2022-06-28T23:36:12Z

Add support for VMD devices in MTL-H/P/U/S/M with bus restriction mode and vector 0 disabled for MSI-X remapping. Link: https://lore.kernel.org/r/20220628221023.190547-1-francisco.munoz.ruiz@linux.intel.com Signed-off-by: Francisco Munoz Signed-off-by: Bjorn Helgaas Reviewed-by: Nirmal Patel