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authorThomas Gleixner <tglx@linutronix.de>2021-12-07 01:27:49 +0300
committerThomas Gleixner <tglx@linutronix.de>2021-12-09 13:52:22 +0300
commit54324c2f3d728f451d9053fcc7859b26fc9cecb4 (patch)
tree19d1e2a59c19c84b1a86d4d7438ef8a3eda3f4d5 /drivers/pci/msi/pcidev_msi.c
parent288c81ce4be7c15544605594966faaeb8803b5da (diff)
downloadlinux-54324c2f3d728f451d9053fcc7859b26fc9cecb4.tar.xz
PCI/MSI: Split out CONFIG_PCI_MSI independent part
These functions are required even when CONFIG_PCI_MSI is not set. Move them to their own file. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Juergen Gross <jgross@suse.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Link: https://lore.kernel.org/r/20211206210224.710137730@linutronix.de
Diffstat (limited to 'drivers/pci/msi/pcidev_msi.c')
-rw-r--r--drivers/pci/msi/pcidev_msi.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/drivers/pci/msi/pcidev_msi.c b/drivers/pci/msi/pcidev_msi.c
new file mode 100644
index 000000000000..5520aff53b56
--- /dev/null
+++ b/drivers/pci/msi/pcidev_msi.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MSI[X} related functions which are available unconditionally.
+ */
+#include "../pci.h"
+
+/*
+ * Disable the MSI[X] hardware to avoid screaming interrupts during boot.
+ * This is the power on reset default so usually this should be a noop.
+ */
+
+void pci_msi_init(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
+ if (!dev->msi_cap)
+ return;
+
+ pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &ctrl);
+ if (ctrl & PCI_MSI_FLAGS_ENABLE) {
+ pci_write_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS,
+ ctrl & ~PCI_MSI_FLAGS_ENABLE);
+ }
+
+ if (!(ctrl & PCI_MSI_FLAGS_64BIT))
+ dev->no_64bit_msi = 1;
+}
+
+void pci_msix_init(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
+ if (!dev->msix_cap)
+ return;
+
+ pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &ctrl);
+ if (ctrl & PCI_MSIX_FLAGS_ENABLE) {
+ pci_write_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS,
+ ctrl & ~PCI_MSIX_FLAGS_ENABLE);
+ }
+}