From de76cda215d56256ffcda7ffa538b70f9fb301a7 Mon Sep 17 00:00:00 2001 From: Gustavo Pimentel Date: Tue, 4 Jun 2019 18:24:43 +0200 Subject: PCI: Decode PCIe 32 GT/s link speed PCIe r5.0, sec 7.5.3.18, defines a new 32.0 GT/s bit in the Supported Link Speeds Vector of Link Capabilities 2. Decode this new speed. This does not affect the speed of the link, which should be negotiated automatically by the hardware; it only adds decoding when showing the speed to the user. Previously, reading the speed of a link operating at this speed showed "Unknown speed" instead of "32.0 GT/s". Link: https://lore.kernel.org/lkml/92365e3caf0fc559f9ab14bcd053bfc92d4f661c.1559664969.git.gustavo.pimentel@synopsys.com Signed-off-by: Gustavo Pimentel [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas --- drivers/pci/probe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 0e8e2c186f50..c5f27c8cd140 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -668,7 +668,7 @@ const unsigned char pcie_link_speed[] = { PCIE_SPEED_5_0GT, /* 2 */ PCIE_SPEED_8_0GT, /* 3 */ PCIE_SPEED_16_0GT, /* 4 */ - PCI_SPEED_UNKNOWN, /* 5 */ + PCIE_SPEED_32_0GT, /* 5 */ PCI_SPEED_UNKNOWN, /* 6 */ PCI_SPEED_UNKNOWN, /* 7 */ PCI_SPEED_UNKNOWN, /* 8 */ -- cgit v1.2.3 From 76bf6a8634a1ac04d3075993c31a6d94a7f75580 Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 13 Jun 2019 16:57:12 -0600 Subject: Revert "PCI/IOV: Use VF0 cached config space size for other VFs" Revert 975bb8b4dc93 ("PCI/IOV: Use VF0 cached config space size for other VFs"), which attempted to cache the config space size from the first VF to re-use for subsequent VFs. The cached value was determined prior to discovering the PCIe capability on the VF, which resulted in the first VF reporting the correct config space size (4K), as it has a special case through pci_cfg_space_size(), while all the other VFs only reported 256 bytes. As this was only a performance optimization, we're better off without it. Fixes: 975bb8b4dc93 ("PCI/IOV: Use VF0 cached config space size for other VFs") Link: https://lore.kernel.org/r/156046663197.29869.3633634445109057665.stgit@gimli.home Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas Cc: KarimAllah Ahmed Cc: Kuppuswamy Sathyanarayanan Cc: Hao Zheng --- drivers/pci/iov.c | 2 -- drivers/pci/pci.h | 1 - drivers/pci/probe.c | 17 ----------------- 3 files changed, 20 deletions(-) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 3aa115ed3a65..525fd3f272b3 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -132,8 +132,6 @@ static void pci_read_vf_config_common(struct pci_dev *virtfn) &physfn->sriov->subsystem_vendor); pci_read_config_word(virtfn, PCI_SUBSYSTEM_ID, &physfn->sriov->subsystem_device); - - physfn->sriov->cfg_size = pci_cfg_space_size(virtfn); } int pci_iov_add_virtfn(struct pci_dev *dev, int id) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 9cb99380c61e..3fc227ef0815 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -293,7 +293,6 @@ struct pci_sriov { u16 driver_max_VFs; /* Max num VFs driver supports */ struct pci_dev *dev; /* Lowest numbered PF */ struct pci_dev *self; /* This PF */ - u32 cfg_size; /* VF config space size */ u32 class; /* VF device */ u8 hdr_type; /* VF header type */ u16 subsystem_vendor; /* VF subsystem vendor */ diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 0e8e2c186f50..a3a3c6b28343 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1555,29 +1555,12 @@ static int pci_cfg_space_size_ext(struct pci_dev *dev) return PCI_CFG_SPACE_EXP_SIZE; } -#ifdef CONFIG_PCI_IOV -static bool is_vf0(struct pci_dev *dev) -{ - if (pci_iov_virtfn_devfn(dev->physfn, 0) == dev->devfn && - pci_iov_virtfn_bus(dev->physfn, 0) == dev->bus->number) - return true; - - return false; -} -#endif - int pci_cfg_space_size(struct pci_dev *dev) { int pos; u32 status; u16 class; -#ifdef CONFIG_PCI_IOV - /* Read cached value for all VFs except for VF0 */ - if (dev->is_virtfn && !is_vf0(dev)) - return dev->physfn->sriov->cfg_size; -#endif - if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG) return PCI_CFG_SPACE_SIZE; -- cgit v1.2.3 From 06013b647c708e4f3179b7b0cf3adf28cb8cbfcf Mon Sep 17 00:00:00 2001 From: Alex Williamson Date: Thu, 13 Jun 2019 16:57:20 -0600 Subject: PCI/IOV: Assume SR-IOV VFs support extended config space. The SR-IOV specification requires both PFs and VFs to implement a PCIe capability. Generally this is sufficient to assume extended config space is present, but we generally also perform additional tests to make sure the extended config space is reachable and not simply an alias of standard config space. For a VF to exist extended config space must be accessible on the PF, therefore we can also assume it to be accessible on the VF. This enables a micro performance optimization previously implemented in commit 975bb8b4dc93 ("PCI/IOV: Use VF0 cached config space size for other VFs") to speed up probing of VFs. Signed-off-by: Alex Williamson Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Cc: KarimAllah Ahmed Cc: Hao Zheng --- drivers/pci/probe.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'drivers/pci/probe.c') diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index a3a3c6b28343..439244ff8f09 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1561,6 +1561,21 @@ int pci_cfg_space_size(struct pci_dev *dev) u32 status; u16 class; +#ifdef CONFIG_PCI_IOV + /* + * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to + * implement a PCIe capability and therefore must implement extended + * config space. We can skip the NO_EXTCFG test below and the + * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of + * the fact that the SR-IOV capability on the PF resides in extended + * config space and must be accessible and non-aliased to have enabled + * support for this VF. This is a micro performance optimization for + * systems supporting many VFs. + */ + if (dev->is_virtfn) + return PCI_CFG_SPACE_EXP_SIZE; +#endif + if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG) return PCI_CFG_SPACE_SIZE; -- cgit v1.2.3