[PATCH v3 1/3] PCI/MSI: Move MSI/MSI-X init to msi.c

Bjorn Helgaas
2020-12-03T18:52:38Z

From: Bjorn Helgaas <bhelgaas@google.com>

Move pci_msi_setup_pci_dev(), which disables MSI and MSI-X interrupts, from
probe.c to msi.c so it's with all the other MSI code and more consistent
with other capability initialization. This means we must compile msi.c
always, even without CONFIG_PCI_MSI, so wrap the rest of msi.c in an #ifdef
and adjust the Makefile accordingly. No functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
drivers/pci/Makefile | 3 +--
drivers/pci/msi.c | 36 ++++++++++++++++++++++++++++++++++++
drivers/pci/pci.h | 2 ++
drivers/pci/probe.c | 21 ++-------------------
4 files changed, 41 insertions(+), 21 deletions(-)

diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
index 522d2b974e91..11cc79411e2d 100644
--- a/drivers/pci/Makefile
+++ b/drivers/pci/Makefile
@@ -5,7 +5,7 @@
obj-$(CONFIG_PCI) += access.o bus.o probe.o host-bridge.o \
remove.o pci.o pci-driver.o search.o \
pci-sysfs.o rom.o setup-res.o irq.o vpd.o \
- setup-bus.o vc.o mmap.o setup-irq.o
+ setup-bus.o vc.o mmap.o setup-irq.o msi.o

obj-$(CONFIG_PCI) += pcie/

@@ -18,7 +18,6 @@ endif
obj-$(CONFIG_OF) += of.o
obj-$(CONFIG_PCI_QUIRKS) += quirks.o
obj-$(CONFIG_HOTPLUG_PCI) += hotplug/
-obj-$(CONFIG_PCI_MSI) += msi.o
obj-$(CONFIG_PCI_ATS) += ats.o
obj-$(CONFIG_PCI_IOV) += iov.o
obj-$(CONFIG_PCI_BRIDGE_EMUL) += pci-bridge-emul.o
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index d52d118979a6..555791c0ee1a 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -26,6 +26,8 @@

#include "pci.h"

+#ifdef CONFIG_MSI
+
static int pci_msi_enable = 1;
int pci_msi_ignore_mask;

@@ -1577,3 +1579,37 @@ bool pci_dev_has_special_msi_domain(struct pci_dev *pdev)
}

#endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */
+#endif /* CONFIG_PCI_MSI */
+
+void pci_msi_init(struct pci_dev *dev)
+{
+ u16 ctrl;
+
+ /*
+ * Disable the MSI hardware to avoid screaming interrupts
+ * during boot. This is the power on reset default so
+ * usually this should be a noop.
+ */
+ 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);
+}
+
+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);
+}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index f86cae9aa1f4..3f5f303775c4 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -104,6 +104,8 @@ void pci_config_pm_runtime_get(struct pci_dev *dev);
void pci_config_pm_runtime_put(struct pci_dev *dev);
void pci_pm_init(struct pci_dev *dev);
void pci_ea_init(struct pci_dev *dev);
+void pci_msi_init(struct pci_dev *dev);
+void pci_msix_init(struct pci_dev *dev);
void pci_allocate_cap_save_buffers(struct pci_dev *dev);
void pci_free_cap_save_buffers(struct pci_dev *dev);
bool pci_bridge_d3_possible(struct pci_dev *dev);
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 4289030b0fff..50b480c016bf 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -1716,22 +1716,6 @@ static u8 pci_hdr_type(struct pci_dev *dev)

#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED)

-static void pci_msi_setup_pci_dev(struct pci_dev *dev)
-{
- /*
- * Disable the MSI hardware to avoid screaming interrupts
- * during boot. This is the power on reset default so
- * usually this should be a noop.
- */
- dev->msi_cap = pci_find_capability(dev, PCI_CAP_ID_MSI);
- if (dev->msi_cap)
- pci_msi_set_enable(dev, 0);
-
- dev->msix_cap = pci_find_capability(dev, PCI_CAP_ID_MSIX);
- if (dev->msix_cap)
- pci_msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0);
-}
-
/**
* pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability
* @dev: PCI device
@@ -2397,9 +2381,8 @@ void pcie_report_downtraining(struct pci_dev *dev)
static void pci_init_capabilities(struct pci_dev *dev)
{
pci_ea_init(dev); /* Enhanced Allocation */
-
- /* Setup MSI caps & disable MSI/MSI-X interrupts */
- pci_msi_setup_pci_dev(dev);
+ pci_msi_init(dev); /* Disable MSI */
+ pci_msix_init(dev); /* Disable MSI-X */

/* Buffers for saving PCIe and PCI-X capabilities */
pci_allocate_cap_save_buffers(dev);
--
2.25.1