PCI: Place interrupt related code into irq.c

Interrupt related code is spread into irq.c, pci.c, and setup-irq.c.
Group them into pre-existing irq.c.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Ilpo Järvinen <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>

drivers/pci/Makefile

···
 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
 
 obj-$(CONFIG_PCI)		+= msi/
 obj-$(CONFIG_PCI)		+= pcie/

drivers/pci/irq.c

···
 
 #include <linux/device.h>
 #include <linux/kernel.h>
+#include <linux/errno.h>
 #include <linux/export.h>
+#include <linux/interrupt.h>
 #include <linux/pci.h>
+
+#include "pci.h"
 
 /**
  * pci_request_irq - allocate an interrupt line for a PCI device
···
 	kfree(free_irq(pci_irq_vector(dev, nr), dev_id));
 }
 EXPORT_SYMBOL(pci_free_irq);
+
+/**
+ * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
+ * @dev: the PCI device
+ * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
+ *
+ * Perform INTx swizzling for a device behind one level of bridge.  This is
+ * required by section 9.1 of the PCI-to-PCI bridge specification for devices
+ * behind bridges on add-in cards.  For devices with ARI enabled, the slot
+ * number is always 0 (see the Implementation Note in section 2.2.8.1 of
+ * the PCI Express Base Specification, Revision 2.1)
+ */
+u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
+{
+	int slot;
+
+	if (pci_ari_enabled(dev->bus))
+		slot = 0;
+	else
+		slot = PCI_SLOT(dev->devfn);
+
+	return (((pin - 1) + slot) % 4) + 1;
+}
+
+int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
+{
+	u8 pin;
+
+	pin = dev->pin;
+	if (!pin)
+		return -1;
+
+	while (!pci_is_root_bus(dev->bus)) {
+		pin = pci_swizzle_interrupt_pin(dev, pin);
+		dev = dev->bus->self;
+	}
+	*bridge = dev;
+	return pin;
+}
+
+/**
+ * pci_common_swizzle - swizzle INTx all the way to root bridge
+ * @dev: the PCI device
+ * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
+ *
+ * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
+ * bridges all the way up to a PCI root bus.
+ */
+u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
+{
+	u8 pin = *pinp;
+
+	while (!pci_is_root_bus(dev->bus)) {
+		pin = pci_swizzle_interrupt_pin(dev, pin);
+		dev = dev->bus->self;
+	}
+	*pinp = pin;
+	return PCI_SLOT(dev->devfn);
+}
+EXPORT_SYMBOL_GPL(pci_common_swizzle);
+
+void pci_assign_irq(struct pci_dev *dev)
+{
+	u8 pin;
+	u8 slot = -1;
+	int irq = 0;
+	struct pci_host_bridge *hbrg = pci_find_host_bridge(dev->bus);
+
+	if (!(hbrg->map_irq)) {
+		pci_dbg(dev, "runtime IRQ mapping not provided by arch\n");
+		return;
+	}
+
+	/*
+	 * If this device is not on the primary bus, we need to figure out
+	 * which interrupt pin it will come in on. We know which slot it
+	 * will come in on because that slot is where the bridge is. Each
+	 * time the interrupt line passes through a PCI-PCI bridge we must
+	 * apply the swizzle function.
+	 */
+	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
+	/* Cope with illegal. */
+	if (pin > 4)
+		pin = 1;
+
+	if (pin) {
+		/* Follow the chain of bridges, swizzling as we go. */
+		if (hbrg->swizzle_irq)
+			slot = (*(hbrg->swizzle_irq))(dev, &pin);
+
+		/*
+		 * If a swizzling function is not used, map_irq() must
+		 * ignore slot.
+		 */
+		irq = (*(hbrg->map_irq))(dev, slot, pin);
+		if (irq == -1)
+			irq = 0;
+	}
+	dev->irq = irq;
+
+	pci_dbg(dev, "assign IRQ: got %d\n", dev->irq);
+
+	/*
+	 * Always tell the device, so the driver knows what is the real IRQ
+	 * to use; the device does not use it.
+	 */
+	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
+}
+
+static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
+{
+	struct pci_bus *bus = dev->bus;
+	bool mask_updated = true;
+	u32 cmd_status_dword;
+	u16 origcmd, newcmd;
+	unsigned long flags;
+	bool irq_pending;
+
+	/*
+	 * We do a single dword read to retrieve both command and status.
+	 * Document assumptions that make this possible.
+	 */
+	BUILD_BUG_ON(PCI_COMMAND % 4);
+	BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
+
+	raw_spin_lock_irqsave(&pci_lock, flags);
+
+	bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
+
+	irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
+
+	/*
+	 * Check interrupt status register to see whether our device
+	 * triggered the interrupt (when masking) or the next IRQ is
+	 * already pending (when unmasking).
+	 */
+	if (mask != irq_pending) {
+		mask_updated = false;
+		goto done;
+	}
+
+	origcmd = cmd_status_dword;
+	newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
+	if (mask)
+		newcmd |= PCI_COMMAND_INTX_DISABLE;
+	if (newcmd != origcmd)
+		bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
+
+done:
+	raw_spin_unlock_irqrestore(&pci_lock, flags);
+
+	return mask_updated;
+}
+
+/**
+ * pci_check_and_mask_intx - mask INTx on pending interrupt
+ * @dev: the PCI device to operate on
+ *
+ * Check if the device dev has its INTx line asserted, mask it and return
+ * true in that case. False is returned if no interrupt was pending.
+ */
+bool pci_check_and_mask_intx(struct pci_dev *dev)
+{
+	return pci_check_and_set_intx_mask(dev, true);
+}
+EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
+
+/**
+ * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
+ * @dev: the PCI device to operate on
+ *
+ * Check if the device dev has its INTx line asserted, unmask it if not and
+ * return true. False is returned and the mask remains active if there was
+ * still an interrupt pending.
+ */
+bool pci_check_and_unmask_intx(struct pci_dev *dev)
+{
+	return pci_check_and_set_intx_mask(dev, false);
+}
+EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
+
+/**
+ * pcibios_penalize_isa_irq - penalize an ISA IRQ
+ * @irq: ISA IRQ to penalize
+ * @active: IRQ active or not
+ *
+ * Permits the platform to provide architecture-specific functionality when
+ * penalizing ISA IRQs. This is the default implementation. Architecture
+ * implementations can override this.
+ */
+void __weak pcibios_penalize_isa_irq(int irq, int active) {}
+
+int __weak pcibios_alloc_irq(struct pci_dev *dev)
+{
+	return 0;
+}
+
+void __weak pcibios_free_irq(struct pci_dev *dev)
+{
+}

drivers/pci/pci-driver.c

···
 	return error;
 }
 
-int __weak pcibios_alloc_irq(struct pci_dev *dev)
-{
-	return 0;
-}
-
-void __weak pcibios_free_irq(struct pci_dev *dev)
-{
-}
-
 #ifdef CONFIG_PCI_IOV
 static inline bool pci_device_can_probe(struct pci_dev *pdev)
 {

drivers/pci/pci.c

···
 #include <linux/log2.h>
 #include <linux/logic_pio.h>
 #include <linux/pm_wakeup.h>
-#include <linux/interrupt.h>
 #include <linux/device.h>
 #include <linux/pm_runtime.h>
 #include <linux/pci_hotplug.h>
···
  */
 void __weak pcibios_disable_device(struct pci_dev *dev) {}
 
-/**
- * pcibios_penalize_isa_irq - penalize an ISA IRQ
- * @irq: ISA IRQ to penalize
- * @active: IRQ active or not
- *
- * Permits the platform to provide architecture-specific functionality when
- * penalizing ISA IRQs. This is the default implementation. Architecture
- * implementations can override this.
- */
-void __weak pcibios_penalize_isa_irq(int irq, int active) {}
-
 static void do_pci_disable_device(struct pci_dev *dev)
 {
 	u16 pci_command;
···
 EXPORT_SYMBOL(pci_enable_atomic_ops_to_root);
 
 /**
- * pci_swizzle_interrupt_pin - swizzle INTx for device behind bridge
- * @dev: the PCI device
- * @pin: the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD)
- *
- * Perform INTx swizzling for a device behind one level of bridge.  This is
- * required by section 9.1 of the PCI-to-PCI bridge specification for devices
- * behind bridges on add-in cards.  For devices with ARI enabled, the slot
- * number is always 0 (see the Implementation Note in section 2.2.8.1 of
- * the PCI Express Base Specification, Revision 2.1)
- */
-u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
-{
-	int slot;
-
-	if (pci_ari_enabled(dev->bus))
-		slot = 0;
-	else
-		slot = PCI_SLOT(dev->devfn);
-
-	return (((pin - 1) + slot) % 4) + 1;
-}
-
-int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge)
-{
-	u8 pin;
-
-	pin = dev->pin;
-	if (!pin)
-		return -1;
-
-	while (!pci_is_root_bus(dev->bus)) {
-		pin = pci_swizzle_interrupt_pin(dev, pin);
-		dev = dev->bus->self;
-	}
-	*bridge = dev;
-	return pin;
-}
-
-/**
- * pci_common_swizzle - swizzle INTx all the way to root bridge
- * @dev: the PCI device
- * @pinp: pointer to the INTx pin value (1=INTA, 2=INTB, 3=INTD, 4=INTD)
- *
- * Perform INTx swizzling for a device.  This traverses through all PCI-to-PCI
- * bridges all the way up to a PCI root bus.
- */
-u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
-{
-	u8 pin = *pinp;
-
-	while (!pci_is_root_bus(dev->bus)) {
-		pin = pci_swizzle_interrupt_pin(dev, pin);
-		dev = dev->bus->self;
-	}
-	*pinp = pin;
-	return PCI_SLOT(dev->devfn);
-}
-EXPORT_SYMBOL_GPL(pci_common_swizzle);
-
-/**
  * pci_release_region - Release a PCI bar
  * @pdev: PCI device whose resources were previously reserved by
  *	  pci_request_region()
···
 	}
 }
 EXPORT_SYMBOL_GPL(pci_intx);
-
-static bool pci_check_and_set_intx_mask(struct pci_dev *dev, bool mask)
-{
-	struct pci_bus *bus = dev->bus;
-	bool mask_updated = true;
-	u32 cmd_status_dword;
-	u16 origcmd, newcmd;
-	unsigned long flags;
-	bool irq_pending;
-
-	/*
-	 * We do a single dword read to retrieve both command and status.
-	 * Document assumptions that make this possible.
-	 */
-	BUILD_BUG_ON(PCI_COMMAND % 4);
-	BUILD_BUG_ON(PCI_COMMAND + 2 != PCI_STATUS);
-
-	raw_spin_lock_irqsave(&pci_lock, flags);
-
-	bus->ops->read(bus, dev->devfn, PCI_COMMAND, 4, &cmd_status_dword);
-
-	irq_pending = (cmd_status_dword >> 16) & PCI_STATUS_INTERRUPT;
-
-	/*
-	 * Check interrupt status register to see whether our device
-	 * triggered the interrupt (when masking) or the next IRQ is
-	 * already pending (when unmasking).
-	 */
-	if (mask != irq_pending) {
-		mask_updated = false;
-		goto done;
-	}
-
-	origcmd = cmd_status_dword;
-	newcmd = origcmd & ~PCI_COMMAND_INTX_DISABLE;
-	if (mask)
-		newcmd |= PCI_COMMAND_INTX_DISABLE;
-	if (newcmd != origcmd)
-		bus->ops->write(bus, dev->devfn, PCI_COMMAND, 2, newcmd);
-
-done:
-	raw_spin_unlock_irqrestore(&pci_lock, flags);
-
-	return mask_updated;
-}
-
-/**
- * pci_check_and_mask_intx - mask INTx on pending interrupt
- * @dev: the PCI device to operate on
- *
- * Check if the device dev has its INTx line asserted, mask it and return
- * true in that case. False is returned if no interrupt was pending.
- */
-bool pci_check_and_mask_intx(struct pci_dev *dev)
-{
-	return pci_check_and_set_intx_mask(dev, true);
-}
-EXPORT_SYMBOL_GPL(pci_check_and_mask_intx);
-
-/**
- * pci_check_and_unmask_intx - unmask INTx if no interrupt is pending
- * @dev: the PCI device to operate on
- *
- * Check if the device dev has its INTx line asserted, unmask it if not and
- * return true. False is returned and the mask remains active if there was
- * still an interrupt pending.
- */
-bool pci_check_and_unmask_intx(struct pci_dev *dev)
-{
-	return pci_check_and_set_intx_mask(dev, false);
-}
-EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx);
 
 /**
  * pci_wait_for_pending_transaction - wait for pending transaction

drivers/pci/setup-irq.c

···
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Support routines for initializing a PCI subsystem
- *
- * Extruded from code written by
- *      Dave Rusling ([e-mail])
- *      David Mosberger ([e-mail])
- *	David Miller ([e-mail])
- */
-
-#include <linux/kernel.h>
-#include <linux/pci.h>
-#include <linux/errno.h>
-#include <linux/ioport.h>
-#include <linux/cache.h>
-#include "pci.h"
-
-void pci_assign_irq(struct pci_dev *dev)
-{
-	u8 pin;
-	u8 slot = -1;
-	int irq = 0;
-	struct pci_host_bridge *hbrg = pci_find_host_bridge(dev->bus);
-
-	if (!(hbrg->map_irq)) {
-		pci_dbg(dev, "runtime IRQ mapping not provided by arch\n");
-		return;
-	}
-
-	/*
-	 * If this device is not on the primary bus, we need to figure out
-	 * which interrupt pin it will come in on. We know which slot it
-	 * will come in on because that slot is where the bridge is. Each
-	 * time the interrupt line passes through a PCI-PCI bridge we must
-	 * apply the swizzle function.
-	 */
-	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
-	/* Cope with illegal. */
-	if (pin > 4)
-		pin = 1;
-
-	if (pin) {
-		/* Follow the chain of bridges, swizzling as we go. */
-		if (hbrg->swizzle_irq)
-			slot = (*(hbrg->swizzle_irq))(dev, &pin);
-
-		/*
-		 * If a swizzling function is not used, map_irq() must
-		 * ignore slot.
-		 */
-		irq = (*(hbrg->map_irq))(dev, slot, pin);
-		if (irq == -1)
-			irq = 0;
-	}
-	dev->irq = irq;
-
-	pci_dbg(dev, "assign IRQ: got %d\n", dev->irq);
-
-	/*
-	 * Always tell the device, so the driver knows what is the real IRQ
-	 * to use; the device does not use it.
-	 */
-	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
-}