[PATCH v13 1/9] PCI: Cache PCIe FLR capability
From: Amey Narkhede <hidden>
Date: 2021-08-01 14:25:36
Also in:
lkml
Subsystem:
pci subsystem, the rest · Maintainers:
Bjorn Helgaas, Linus Torvalds
Add a new member called devcap in struct pci_dev for caching the device capabilities to avoid reading PCI_EXP_DEVCAP multiple times. Refactor pcie_has_flr() to use cached device capabilities. Signed-off-by: Amey Narkhede <redacted> --- 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 452351025a09..1fafd05caa41 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c@@ -31,6 +31,7 @@ #include <linux/vmalloc.h> #include <asm/dma.h> #include <linux/aer.h> +#include <linux/bitfield.h> #include "pci.h" DEFINE_MUTEX(pci_slot_mutex);
@@ -4620,13 +4621,10 @@ 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 3a62d09b8869..df3f9db6e151 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c@@ -19,6 +19,7 @@ #include <linux/hypervisor.h> #include <linux/irqdomain.h> #include <linux/pm_runtime.h> +#include <linux/bitfield.h> #include "pci.h" #define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */
@@ -1497,8 +1498,8 @@ 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 c20211e59a57..697b1f085c7b 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 */
--
2.32.0