kernel/git/stable/linux.git/drivers/pci/host, branch linux-4.14.y

PCI: hv: Fix interrupt mapping for multi-MSI

2022-07-29T15:06:53+00:00

commit a2bad844a67b1c7740bda63e87453baf63c3a7f7 upstream. According to Dexuan, the hypervisor folks beleive that multi-msi allocations are not correct. compose_msi_msg() will allocate multi-msi one by one. However, multi-msi is a block of related MSIs, with alignment requirements. In order for the hypervisor to allocate properly aligned and consecutive entries in the IOMMU Interrupt Remapping Table, there should be a single mapping request that requests all of the multi-msi vectors in one shot. Dexuan suggests detecting the multi-msi case and composing a single request related to the first MSI. Then for the other MSIs in the same block, use the cached information. This appears to be viable, so do it. 4.14 backport - file moved to host/pci-hyperv.c. add hv_msi_get_int_vector helper function. Fixed merge conflict due to delivery_mode name change (APIC_DELIVERY_MODE_FIXED is the value given to dest_Fixed). Removed unused variable in hv_compose_msi_msg. Fixed reference to msi_desc->pci to point to the same is_msix variable. Removed changes to compose_msi_req_v3 since it doesn't exist yet. Added "reason" to put_pcichild (unused in function). Suggested-by: Dexuan Cui Signed-off-by: Jeffrey Hugo Reviewed-by: Dexuan Cui Tested-by: Michael Kelley Link: https://lore.kernel.org/r/1652282599-21643-1-git-send-email-quic_jhugo@quicinc.com Signed-off-by: Wei Liu Signed-off-by: Carl Vanderlip Signed-off-by: Greg Kroah-Hartman

PCI: hv: Reuse existing IRTE allocation in compose_msi_msg()

2022-07-29T15:06:53+00:00

commit b4b77778ecc5bfbd4e77de1b2fd5c1dd3c655f1f upstream. Currently if compose_msi_msg() is called multiple times, it will free any previous IRTE allocation, and generate a new allocation. While nothing prevents this from occurring, it is extraneous when Linux could just reuse the existing allocation and avoid a bunch of overhead. However, when future IRTE allocations operate on blocks of MSIs instead of a single line, freeing the allocation will impact all of the lines. This could cause an issue where an allocation of N MSIs occurs, then some of the lines are retargeted, and finally the allocation is freed/reallocated. The freeing of the allocation removes all of the configuration for the entire block, which requires all the lines to be retargeted, which might not happen since some lines might already be unmasked/active. 4.14 backport - driver location change to host/pci-hyperv.c Signed-off-by: Jeffrey Hugo Reviewed-by: Dexuan Cui Tested-by: Dexuan Cui Tested-by: Michael Kelley Link: https://lore.kernel.org/r/1652282582-21595-1-git-send-email-quic_jhugo@quicinc.com Signed-off-by: Wei Liu Signed-off-by: Carl Vanderlip Signed-off-by: Greg Kroah-Hartman

PCI: hv: Fix hv_arch_irq_unmask() for multi-MSI

2022-07-29T15:06:53+00:00

commit 455880dfe292a2bdd3b4ad6a107299fce610e64b upstream. In the multi-MSI case, hv_arch_irq_unmask() will only operate on the first MSI of the N allocated. This is because only the first msi_desc is cached and it is shared by all the MSIs of the multi-MSI block. This means that hv_arch_irq_unmask() gets the correct address, but the wrong data (always 0). This can break MSIs. Lets assume MSI0 is vector 34 on CPU0, and MSI1 is vector 33 on CPU0. hv_arch_irq_unmask() is called on MSI0. It uses a hypercall to configure the MSI address and data (0) to vector 34 of CPU0. This is correct. Then hv_arch_irq_unmask is called on MSI1. It uses another hypercall to configure the MSI address and data (0) to vector 33 of CPU0. This is wrong, and results in both MSI0 and MSI1 being routed to vector 33. Linux will observe extra instances of MSI1 and no instances of MSI0 despite the endpoint device behaving correctly. For the multi-MSI case, we need unique address and data info for each MSI, but the cached msi_desc does not provide that. However, that information can be gotten from the int_desc cached in the chip_data by compose_msi_msg(). Fix the multi-MSI case to use that cached information instead. Since hv_set_msi_entry_from_desc() is no longer applicable, remove it. 4.14 backport - moved to host/pci-hyperv.c. hv_set_msi_entry_from_desc doesn't exist to be removed. int_entry replaces msi_entry for location int_desc is written to. Signed-off-by: Jeffrey Hugo Reviewed-by: Michael Kelley Link: https://lore.kernel.org/r/1651068453-29588-1-git-send-email-quic_jhugo@quicinc.com Signed-off-by: Wei Liu Signed-off-by: Carl Vanderlip Signed-off-by: Greg Kroah-Hartman

PCI: hv: Fix multi-MSI to allow more than one MSI vector

2022-07-29T15:06:53+00:00

commit 08e61e861a0e47e5e1a3fb78406afd6b0cea6b6d upstream. If the allocation of multiple MSI vectors for multi-MSI fails in the core PCI framework, the framework will retry the allocation as a single MSI vector, assuming that meets the min_vecs specified by the requesting driver. Hyper-V advertises that multi-MSI is supported, but reuses the VECTOR domain to implement that for x86. The VECTOR domain does not support multi-MSI, so the alloc will always fail and fallback to a single MSI allocation. In short, Hyper-V advertises a capability it does not implement. Hyper-V can support multi-MSI because it coordinates with the hypervisor to map the MSIs in the IOMMU's interrupt remapper, which is something the VECTOR domain does not have. Therefore the fix is simple - copy what the x86 IOMMU drivers (AMD/Intel-IR) do by removing X86_IRQ_ALLOC_CONTIGUOUS_VECTORS after calling the VECTOR domain's pci_msi_prepare(). 4.14 backport - file location change to host/pci-hyperv.c. adds the hv_msi_prepare wrapper function. X86_IRQ_ALLOC_TYPE_PCI_MSI changed to X86_IRQ_ALLOC_TYPE_MSI (same value). Fixes: 4daace0d8ce8 ("PCI: hv: Add paravirtual PCI front-end for Microsoft Hyper-V VMs") Signed-off-by: Jeffrey Hugo Reviewed-by: Dexuan Cui Link: https://lore.kernel.org/r/1649856981-14649-1-git-send-email-quic_jhugo@quicinc.com Signed-off-by: Wei Liu Signed-off-by: Carl Vanderlip Signed-off-by: Greg Kroah-Hartman

PCI: aardvark: Fix reading MSI interrupt number

2022-05-12T10:17:11+00:00

commit 805dfc18dd3d4dd97a987d4406593b5a225b1253 upstream. In advk_pcie_handle_msi() it is expected that when bit i in the W1C register PCIE_MSI_STATUS_REG is cleared, the PCIE_MSI_PAYLOAD_REG is updated to contain the MSI number corresponding to index i. Experiments show that this is not so, and instead PCIE_MSI_PAYLOAD_REG always contains the number of the last received MSI, overall. Do not read PCIE_MSI_PAYLOAD_REG register for determining MSI interrupt number. Since Aardvark already forbids more than 32 interrupts and uses own allocated hwirq numbers, the msi_idx already corresponds to the received MSI number. Link: https://lore.kernel.org/r/20220110015018.26359-3-kabel@kernel.org Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver") Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Signed-off-by: Marek Behún Signed-off-by: Greg Kroah-Hartman

PCI: aardvark: Clear all MSIs at setup

2022-05-12T10:17:10+00:00

commit 7d8dc1f7cd007a7ce94c5b4c20d63a8b8d6d7751 upstream. We already clear all the other interrupts (ISR0, ISR1, HOST_CTRL_INT). Define a new macro PCIE_MSI_ALL_MASK and do the same clearing for MSIs, to ensure that we don't start receiving spurious interrupts. Use this new mask in advk_pcie_handle_msi(); Link: https://lore.kernel.org/r/20211130172913.9727-5-kabel@kernel.org Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Signed-off-by: Marek Behún Signed-off-by: Greg Kroah-Hartman

PCI: aardvark: Fix support for MSI interrupts

2022-04-20T07:08:26+00:00

[ Upstream commit b0b0b8b897f8e12b2368e868bd7cdc5742d5c5a9 ] Aardvark hardware supports Multi-MSI and MSI_FLAG_MULTI_PCI_MSI is already set for the MSI chip. But when allocating MSI interrupt numbers for Multi-MSI, the numbers need to be properly aligned, otherwise endpoint devices send MSI interrupt with incorrect numbers. Fix this issue by using function bitmap_find_free_region() instead of bitmap_find_next_zero_area(). To ensure that aligned MSI interrupt numbers are used by endpoint devices, we cannot use Linux virtual irq numbers (as they are random and not properly aligned). Instead we need to use the aligned hwirq numbers. This change fixes receiving MSI interrupts on Armada 3720 boards and allows using NVMe disks which use Multi-MSI feature with 3 interrupts. Without this NVMe disks freeze booting as linux nvme-core.c is waiting 60s for an interrupt. Link: https://lore.kernel.org/r/20220110015018.26359-4-kabel@kernel.org Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Signed-off-by: Sasha Levin

PCI: aardvark: Fix checking for link up via LTSSM state

2021-12-08T07:46:51+00:00

commit 661c399a651c11aaf83c45cbfe0b4a1fb7bc3179 upstream. Current implementation of advk_pcie_link_up() is wrong as it marks also link disabled or hot reset states as link up. Fix it by marking link up only to those states which are defined in PCIe Base specification 3.0, Table 4-14: Link Status Mapped to the LTSSM. To simplify implementation, Define macros for every LTSSM state which aardvark hardware can return in CFG_REG register. Fix also checking for link training according to the same Table 4-14. Define a new function advk_pcie_link_training() for this purpose. Link: https://lore.kernel.org/r/20211005180952.6812-13-kabel@kernel.org Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver") Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Reviewed-by: Marek Behún Cc: stable@vger.kernel.org Cc: Remi Pommarel Signed-off-by: Marek Behún Signed-off-by: Greg Kroah-Hartman

PCI: aardvark: Fix link training

2021-12-08T07:46:51+00:00

commit f76b36d40beee0a13aa8f6aa011df0d7cbbb8a7f upstream. Fix multiple link training issues in aardvark driver. The main reason of these issues was misunderstanding of what certain registers do, since their names and comments were misleading: before commit 96be36dbffac ("PCI: aardvark: Replace custom macros by standard linux/pci_regs.h macros"), the pci-aardvark.c driver used custom macros for accessing standard PCIe Root Bridge registers, and misleading comments did not help to understand what the code was really doing. After doing more tests and experiments I've come to the conclusion that the SPEED_GEN register in aardvark sets the PCIe revision / generation compliance and forces maximal link speed. Both GEN3 and GEN2 values set the read-only PCI_EXP_FLAGS_VERS bits (PCIe capabilities version of Root Bridge) to value 2, while GEN1 value sets PCI_EXP_FLAGS_VERS to 1, which matches with PCI Express specifications revisions 3, 2 and 1 respectively. Changing SPEED_GEN also sets the read-only bits PCI_EXP_LNKCAP_SLS and PCI_EXP_LNKCAP2_SLS to corresponding speed. (Note that PCI Express rev 1 specification does not define PCI_EXP_LNKCAP2 and PCI_EXP_LNKCTL2 registers and when SPEED_GEN is set to GEN1 (which also sets PCI_EXP_FLAGS_VERS set to 1), lspci cannot access PCI_EXP_LNKCAP2 and PCI_EXP_LNKCTL2 registers.) Changing PCIe link speed can be done via PCI_EXP_LNKCTL2_TLS bits of PCI_EXP_LNKCTL2 register. Armada 3700 Functional Specifications says that the default value of PCI_EXP_LNKCTL2_TLS is based on SPEED_GEN value, but tests showed that the default value is always 8.0 GT/s, independently of speed set by SPEED_GEN. So after setting SPEED_GEN, we must also set value in PCI_EXP_LNKCTL2 register via PCI_EXP_LNKCTL2_TLS bits. Triggering PCI_EXP_LNKCTL_RL bit immediately after setting LINK_TRAINING_EN bit actually doesn't do anything. Tests have shown that a delay is needed after enabling LINK_TRAINING_EN bit. As triggering PCI_EXP_LNKCTL_RL currently does nothing, remove it. Commit 43fc679ced18 ("PCI: aardvark: Improve link training") introduced code which sets SPEED_GEN register based on negotiated link speed from PCI_EXP_LNKSTA_CLS bits of PCI_EXP_LNKSTA register. This code was added to fix detection of Compex WLE900VX (Atheros QCA9880) WiFi GEN1 PCIe cards, as otherwise these cards were "invisible" on PCIe bus (probably because they crashed). But apparently more people reported the same issues with these cards also with other PCIe controllers [1] and I was able to reproduce this issue also with other "noname" WiFi cards based on Atheros QCA9890 chip (with the same PCI vendor/device ids as Atheros QCA9880). So this is not an issue in aardvark but rather an issue in Atheros QCA98xx chips. Also, this issue only exists if the kernel is compiled with PCIe ASPM support, and a generic workaround for this is to change PCIe Bridge to 2.5 GT/s link speed via PCI_EXP_LNKCTL2_TLS_2_5GT bits in PCI_EXP_LNKCTL2 register [2], before triggering PCI_EXP_LNKCTL_RL bit. This workaround also works when SPEED_GEN is set to value GEN2 (5 GT/s). So remove this hack completely in the aardvark driver and always set SPEED_GEN to value from 'max-link-speed' DT property. Fix for Atheros QCA98xx chips is handled separately by patch [2]. These two things (code for triggering PCI_EXP_LNKCTL_RL bit and changing SPEED_GEN value) also explain why commit 6964494582f5 ("PCI: aardvark: Train link immediately after enabling training") somehow fixed detection of those problematic Compex cards with Atheros chips: if triggering link retraining (via PCI_EXP_LNKCTL_RL bit) was done immediately after enabling link training (via LINK_TRAINING_EN), it did nothing. If there was a specific delay, aardvark HW already initialized PCIe link and therefore triggering link retraining caused the above issue. Compex cards triggered link down event and disappeared from the PCIe bus. Commit f4c7d053d7f7 ("PCI: aardvark: Wait for endpoint to be ready before training link") added 100ms sleep before calling 'Start link training' command and explained that it is a requirement of PCI Express specification. But the code after this 100ms sleep was not doing 'Start link training', rather it triggered PCI_EXP_LNKCTL_RL bit via PCIe Root Bridge to put link into Recovery state. The required delay after fundamental reset is already done in function advk_pcie_wait_for_link() which also checks whether PCIe link is up. So after removing the code which triggers PCI_EXP_LNKCTL_RL bit on PCIe Root Bridge, there is no need to wait 100ms again. Remove the extra msleep() call and update comment about the delay required by the PCI Express specification. According to Marvell Armada 3700 Functional Specifications, Link training should be enabled via aardvark register LINK_TRAINING_EN after selecting PCIe generation and x1 lane. There is no need to disable it prior resetting card via PERST# signal. This disabling code was introduced in commit 5169a9851daa ("PCI: aardvark: Issue PERST via GPIO") as a workaround for some Atheros cards. It turns out that this also is Atheros specific issue and affects any PCIe controller, not only aardvark. Moreover this Atheros issue was triggered by juggling with PCI_EXP_LNKCTL_RL, LINK_TRAINING_EN and SPEED_GEN bits interleaved with sleeps. Now, after removing triggering PCI_EXP_LNKCTL_RL, there is no need to explicitly disable LINK_TRAINING_EN bit. So remove this code too. The problematic Compex cards described in previous git commits are correctly detected in advk_pcie_train_link() function even after applying all these changes. Note that with this patch, and also prior this patch, some NVMe disks which support PCIe GEN3 with 8 GT/s speed are negotiated only at the lowest link speed 2.5 GT/s, independently of SPEED_GEN value. After manually triggering PCI_EXP_LNKCTL_RL bit (e.g. from userspace via setpci), these NVMe disks change link speed to 5 GT/s when SPEED_GEN was configured to GEN2. This issue first needs to be properly investigated. I will send a fix in the future. On the other hand, some other GEN2 PCIe cards with 5 GT/s speed are autonomously by HW autonegotiated at full 5 GT/s speed without need of any software interaction. Armada 3700 Functional Specifications describes the following steps for link training: set SPEED_GEN to GEN2, enable LINK_TRAINING_EN, poll until link training is complete, trigger PCI_EXP_LNKCTL_RL, poll until signal rate is 5 GT/s, poll until link training is complete, enable ASPM L0s. The requirement for triggering PCI_EXP_LNKCTL_RL can be explained by the need to achieve 5 GT/s speed (as changing link speed is done by throw to recovery state entered by PCI_EXP_LNKCTL_RL) or maybe as a part of enabling ASPM L0s (but in this case ASPM L0s should have been enabled prior PCI_EXP_LNKCTL_RL). It is unknown why the original pci-aardvark.c driver was triggering PCI_EXP_LNKCTL_RL bit before waiting for the link to be up. This does not align with neither PCIe base specifications nor with Armada 3700 Functional Specification. (Note that in older versions of aardvark, this bit was called incorrectly PCIE_CORE_LINK_TRAINING, so this may be the reason.) It is also unknown why Armada 3700 Functional Specification says that it is needed to trigger PCI_EXP_LNKCTL_RL for GEN2 mode, as according to PCIe base specification 5 GT/s speed negotiation is supposed to be entirely autonomous, even if initial speed is 2.5 GT/s. [1] - https://lore.kernel.org/linux-pci/87h7l8axqp.fsf@toke.dk/ [2] - https://lore.kernel.org/linux-pci/20210326124326.21163-1-pali@kernel.org/ Link: https://lore.kernel.org/r/20211005180952.6812-12-kabel@kernel.org Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Reviewed-by: Marek Behún Signed-off-by: Greg Kroah-Hartman

PCI: aardvark: Fix PCIe Max Payload Size setting

2021-12-08T07:46:51+00:00

commit a4e17d65dafdd3513042d8f00404c9b6068a825c upstream. Change PCIe Max Payload Size setting in PCIe Device Control register to 512 bytes to align with PCIe Link Initialization sequence as defined in Marvell Armada 3700 Functional Specification. According to the specification, maximal Max Payload Size supported by this device is 512 bytes. Without this kernel prints suspicious line: pci 0000:01:00.0: Upstream bridge's Max Payload Size set to 256 (was 16384, max 512) With this change it changes to: pci 0000:01:00.0: Upstream bridge's Max Payload Size set to 256 (was 512, max 512) Link: https://lore.kernel.org/r/20211005180952.6812-3-kabel@kernel.org Fixes: 8c39d710363c ("PCI: aardvark: Add Aardvark PCI host controller driver") Signed-off-by: Pali Rohár Signed-off-by: Marek Behún Signed-off-by: Lorenzo Pieralisi Reviewed-by: Marek Behún Cc: stable@vger.kernel.org Signed-off-by: Marek Behún Signed-off-by: Greg Kroah-Hartman