1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * MSI[X} related functions which are available unconditionally. 4 */ 5 #include "../pci.h" 6 7 /* 8 * Disable the MSI[X] hardware to avoid screaming interrupts during boot. 9 * This is the power on reset default so usually this should be a noop. 10 */ 11 12 void pci_msi_init(struct pci_dev *dev) 13 { 14 u16 ctrl; 15 16 dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI); 17 if (!dev->msi_cap) 18 return; 19 20 pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl); 21 if (ctrl & PCI_MSI_FLAGS_ENABLE) { 22 pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, 23 ctrl & ~PCI_MSI_FLAGS_ENABLE); 24 } 25 26 if (!(ctrl & PCI_MSI_FLAGS_64BIT)) 27 dev->no_64bit_msi = 1; 28 } 29 30 void pci_msix_init(struct pci_dev *dev) 31 { 32 u16 ctrl; 33 34 dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX); 35 if (!dev->msix_cap) 36 return; 37 38 pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl); 39 if (ctrl & PCI_MSIX_FLAGS_ENABLE) { 40 pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, 41 ctrl & ~PCI_MSIX_FLAGS_ENABLE); 42 } 43 } 44