From 703860ed4e36ded696bd44af6107243fdedfb746 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 17 Apr 2013 16:57:56 -0600 Subject: PCI: Use u8, not int, for PM capability offset The Power Management Capability (PCI_CAP_ID_PM == 0x01) is defined by PCI and must appear in the 256-byte PCI Configuration Space from 0-0xff. It cannot be in the PCIe Extended Configuration space from 0x100-0xfff, so we only need a u8 to hold its offset. Signed-off-by: Bjorn Helgaas Acked-by: Rafael J. Wysocki --- include/linux/pci.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'include/linux/pci.h') diff --git a/include/linux/pci.h b/include/linux/pci.h index 2461033a7987..9587d4d19279 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -249,8 +249,7 @@ struct pci_dev { pci_power_t current_state; /* Current operating state. In ACPI-speak, this is D0-D3, D0 being fully functional, and D3 being off. */ - int pm_cap; /* PM capability offset in the - configuration space */ + u8 pm_cap; /* PM capability offset */ unsigned int pme_support:5; /* Bitmask of states from which PME# can be generated */ unsigned int pme_interrupt:1; -- cgit v1.2.3 From e375b561817d9ae098cc4296a729fc88924a0159 Mon Sep 17 00:00:00 2001 From: Gavin Shan Date: Thu, 4 Apr 2013 16:54:30 +0000 Subject: PCI: Cache MSI/MSI-X capability offsets in struct pci_dev The patch caches the MSI and MSI-X capability offset in PCI device (struct pci_dev) so that we needn't read it from the config space upon enabling or disabling MSI or MSI-X interrupts. [bhelgaas: moved pm_cap size change to separate patch] Signed-off-by: Gavin Shan Signed-off-by: Bjorn Helgaas --- drivers/pci/msi.c | 42 +++++++++++++++++++----------------------- include/linux/pci.h | 2 ++ 2 files changed, 21 insertions(+), 23 deletions(-) (limited to 'include/linux/pci.h') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 00cc78c7aa04..99befbd99938 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -111,32 +111,26 @@ void default_restore_msi_irqs(struct pci_dev *dev, int irq) } #endif -static void msi_set_enable(struct pci_dev *dev, int pos, int enable) +static void msi_set_enable(struct pci_dev *dev, int enable) { u16 control; - BUG_ON(!pos); - - pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &control); control &= ~PCI_MSI_FLAGS_ENABLE; if (enable) control |= PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); + pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, control); } static void msix_set_enable(struct pci_dev *dev, int enable) { - int pos; u16 control; - pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); - if (pos) { - pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); - control &= ~PCI_MSIX_FLAGS_ENABLE; - if (enable) - control |= PCI_MSIX_FLAGS_ENABLE; - pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); - } + pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); + control &= ~PCI_MSIX_FLAGS_ENABLE; + if (enable) + control |= PCI_MSIX_FLAGS_ENABLE; + pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, control); } static inline __attribute_const__ u32 msi_mask(unsigned x) @@ -402,7 +396,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev) pos = entry->msi_attrib.pos; pci_intx_for_msi(dev, 0); - msi_set_enable(dev, pos, 0); + msi_set_enable(dev, 0); arch_restore_msi_irqs(dev, dev->irq); pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); @@ -557,7 +551,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) unsigned mask; pos = pci_find_capability(dev, PCI_CAP_ID_MSI); - msi_set_enable(dev, pos, 0); /* Disable MSI during set up */ + msi_set_enable(dev, 0); /* Disable MSI during set up */ pci_read_config_word(dev, msi_control_reg(pos), &control); /* MSI Entry Initialization */ @@ -598,7 +592,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) /* Set MSI enabled bits */ pci_intx_for_msi(dev, 0); - msi_set_enable(dev, pos, 1); + msi_set_enable(dev, 1); dev->msi_enabled = 1; dev->irq = entry->irq; @@ -885,7 +879,7 @@ void pci_msi_shutdown(struct pci_dev *dev) desc = list_first_entry(&dev->msi_list, struct msi_desc, list); pos = desc->msi_attrib.pos; - msi_set_enable(dev, pos, 0); + msi_set_enable(dev, 0); pci_intx_for_msi(dev, 1); dev->msi_enabled = 0; @@ -1048,15 +1042,17 @@ EXPORT_SYMBOL(pci_msi_enabled); void pci_msi_init_pci_dev(struct pci_dev *dev) { - int pos; INIT_LIST_HEAD(&dev->msi_list); /* Disable the msi hardware to avoid screaming interrupts * during boot. This is the power on reset default so * usually this should be a noop. */ - pos = pci_find_capability(dev, PCI_CAP_ID_MSI); - if (pos) - msi_set_enable(dev, pos, 0); - msix_set_enable(dev, 0); + dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI); + if (dev->msi_cap) + msi_set_enable(dev, 0); + + dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX); + if (dev->msix_cap) + msix_set_enable(dev, 0); } diff --git a/include/linux/pci.h b/include/linux/pci.h index 9587d4d19279..b73c2460ad57 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -232,6 +232,8 @@ struct pci_dev { u8 revision; /* PCI revision, low byte of class word */ u8 hdr_type; /* PCI header type (`multi' flag masked out) */ u8 pcie_cap; /* PCI-E capability offset */ + u8 msi_cap; /* MSI capability offset */ + u8 msix_cap; /* MSI-X capability offset */ u8 pcie_mpss:3; /* PCI-E Max Payload Size Supported */ u8 rom_base_reg; /* which config register controls the ROM */ u8 pin; /* which interrupt pin this device uses */ -- cgit v1.2.3