[PATCH V2 2/4] Revert "ACPI, PCI, IRQ: remove redundant code in acpi_irq_penalty_init()"

[Sinan Kaya]

Trying to make the ISA and PCI init functionality common turned out to be
a bad idea. ISA path depends on external functionality. Restoring the
previous behavior and limiting the refactoring to PCI interrupts only.

This reverts commit 1fcb6a813c4f ("ACPI,PCI,IRQ: remove redundant code in
acpi_irq_penalty_init()").

Signed-off-by: Sinan Kaya <okaya at codeaurora.org>
---
 arch/x86/pci/acpi.c         |  1 +
 drivers/acpi/pci_link.c     | 36 ++++++++++++++++++++++++++++++++++++
 include/acpi/acpi_drivers.h |  1 +
 3 files changed, 38 insertions(+)

diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c
index b2a4e2a..3cd6983 100644
--- a/arch/x86/pci/acpi.c
+++ b/arch/x86/pci/acpi.c
@@ -396,6 +396,7 @@ int __init pci_acpi_init(void)
 		return -ENODEV;
 
 	printk(KERN_INFO "PCI: Using ACPI for IRQ routing\n");
+	acpi_irq_penalty_init();
 	pcibios_enable_irq = acpi_pci_irq_enable;
 	pcibios_disable_irq = acpi_pci_irq_disable;
 	x86_init.pci.init_irq = x86_init_noop;
diff --git a/drivers/acpi/pci_link.c b/drivers/acpi/pci_link.c
index f2b69e3..714ba4d 100644
--- a/drivers/acpi/pci_link.c
+++ b/drivers/acpi/pci_link.c
@@ -517,6 +517,42 @@ static int acpi_irq_get_penalty(int irq)
 	return penalty;
 }
 
+int __init acpi_irq_penalty_init(void)
+{
+	struct acpi_pci_link *link;
+	int i;
+
+	/*
+	 * Update penalties to facilitate IRQ balancing.
+	 */
+	list_for_each_entry(link, &acpi_link_list, list) {
+
+		/*
+		 * reflect the possible and active irqs in the penalty table --
+		 * useful for breaking ties.
+		 */
+		if (link->irq.possible_count) {
+			int penalty =
+			    PIRQ_PENALTY_PCI_POSSIBLE /
+			    link->irq.possible_count;
+
+			for (i = 0; i < link->irq.possible_count; i++) {
+				if (link->irq.possible[i] < ACPI_MAX_ISA_IRQS)
+					acpi_isa_irq_penalty[link->irq.
+							 possible[i]] +=
+					    penalty;
+			}
+
+		} else if (link->irq.active &&
+				(link->irq.active < ACPI_MAX_ISA_IRQS)) {
+			acpi_isa_irq_penalty[link->irq.active] +=
+			    PIRQ_PENALTY_PCI_POSSIBLE;
+		}
+	}
+
+	return 0;
+}
+
 static int acpi_irq_balance = -1;	/* 0: static, 1: balance */
 
 static int acpi_pci_link_allocate(struct acpi_pci_link *link)
diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h
index 797ae2e..29c6912 100644
--- a/include/acpi/acpi_drivers.h
+++ b/include/acpi/acpi_drivers.h
@@ -78,6 +78,7 @@
 
 /* ACPI PCI Interrupt Link (pci_link.c) */
 
+int acpi_irq_penalty_init(void);
 int acpi_pci_link_allocate_irq(acpi_handle handle, int index, int *triggering,
 			       int *polarity, char **name);
 int acpi_pci_link_free_irq(acpi_handle handle);
-- 
1.8.2.1