From 69139244806537f9d51364f37fe146bb2ee88a05 Mon Sep 17 00:00:00 2001 From: Amey Narkhede Date: Tue, 17 Aug 2021 23:34:52 +0530 Subject: [PATCH] PCI: Cache PCIe Device Capabilities register Add a new member called devcap in struct pci_dev for caching the PCIe Device Capabilities register to avoid reading PCI_EXP_DEVCAP multiple times. Refactor pcie_has_flr() to use cached device capabilities. Link: https://lore.kernel.org/r/20210817180500.1253-2-ameynarkhede03@gmail.com Signed-off-by: Amey Narkhede Signed-off-by: Bjorn Helgaas Reviewed-by: Raphael Norwitz --- drivers/pci/pci.c | 6 ++---- drivers/pci/probe.c | 5 +++-- include/linux/pci.h | 1 + 3 files changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index aacf575c15cff..b7a9f680c5132 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "pci.h" DEFINE_MUTEX(pci_slot_mutex); @@ -4630,13 +4631,10 @@ EXPORT_SYMBOL(pci_wait_for_pending_transaction); */ bool pcie_has_flr(struct pci_dev *dev) { - u32 cap; - if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET) return false; - pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap); - return cap & PCI_EXP_DEVCAP_FLR; + return FIELD_GET(PCI_EXP_DEVCAP_FLR, dev->devcap) == 1; } EXPORT_SYMBOL_GPL(pcie_has_flr); diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 79177ac37880f..81eb88ae43018 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -19,6 +19,7 @@ #include #include #include +#include #include "pci.h" #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */ @@ -1498,8 +1499,8 @@ void set_pcie_port_type(struct pci_dev *pdev) pdev->pcie_cap = pos; pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16); pdev->pcie_flags_reg = reg16; - pci_read_config_word(pdev, pos + PCI_EXP_DEVCAP, ®16); - pdev->pcie_mpss = reg16 & PCI_EXP_DEVCAP_PAYLOAD; + pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->devcap); + pdev->pcie_mpss = FIELD_GET(PCI_EXP_DEVCAP_PAYLOAD, pdev->devcap); parent = pci_upstream_bridge(pdev); if (!parent) diff --git a/include/linux/pci.h b/include/linux/pci.h index 540b377ca8f61..1179c0ee2bfb9 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -333,6 +333,7 @@ struct pci_dev { struct rcec_ea *rcec_ea; /* RCEC cached endpoint association */ struct pci_dev *rcec; /* Associated RCEC device */ #endif + u32 devcap; /* PCIe Device Capabilities */ u8 pcie_cap; /* PCIe capability offset */ u8 msi_cap; /* MSI capability offset */ u8 msix_cap; /* MSI-X capability offset */