[PATCH] PCI: msi abstractions and support for altix

Abstract portions of the MSI core for platforms that do not use standard
APIC interrupt controllers.  This is implemented through a new arch-specific
msi setup routine, and a set of msi ops which can be set on a per platform
basis.

Signed-off-by: Mark Maule <maule@sgi.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 100 insertions, 0 deletions

diff --git a/drivers/pci/msi-apic.c b/drivers/pci/msi-apic.c
new file mode 100644
index 000000000000..0eb5fe9003a2
--- /dev/null
+++ b/drivers/pci/msi-apic.c
@@ -0,0 +1,100 @@
+/*
+ * MSI hooks for standard x86 apic
+ */
+
+#include <linux/pci.h>
+#include <linux/irq.h>
+
+#include "msi.h"
+
+/*
+ * Shifts for APIC-based data
+ */
+
+#define MSI_DATA_VECTOR_SHIFT           0
+#define     MSI_DATA_VECTOR(v)          (((u8)v) << MSI_DATA_VECTOR_SHIFT)
+
+#define MSI_DATA_DELIVERY_SHIFT         8
+#define     MSI_DATA_DELIVERY_FIXED     (0 << MSI_DATA_DELIVERY_SHIFT)
+#define     MSI_DATA_DELIVERY_LOWPRI    (1 << MSI_DATA_DELIVERY_SHIFT)
+
+#define MSI_DATA_LEVEL_SHIFT            14
+#define     MSI_DATA_LEVEL_DEASSERT     (0 << MSI_DATA_LEVEL_SHIFT)
+#define     MSI_DATA_LEVEL_ASSERT       (1 << MSI_DATA_LEVEL_SHIFT)
+
+#define MSI_DATA_TRIGGER_SHIFT          15
+#define     MSI_DATA_TRIGGER_EDGE       (0 << MSI_DATA_TRIGGER_SHIFT)
+#define     MSI_DATA_TRIGGER_LEVEL      (1 << MSI_DATA_TRIGGER_SHIFT)
+
+/*
+ * Shift/mask fields for APIC-based bus address
+ */
+
+#define MSI_ADDR_HEADER                 0xfee00000
+
+#define MSI_ADDR_DESTID_MASK            0xfff0000f
+#define     MSI_ADDR_DESTID_CPU(cpu)    ((cpu) << MSI_TARGET_CPU_SHIFT)
+
+#define MSI_ADDR_DESTMODE_SHIFT         2
+#define     MSI_ADDR_DESTMODE_PHYS      (0 << MSI_ADDR_DESTMODE_SHIFT)
+#define     MSI_ADDR_DESTMODE_LOGIC     (1 << MSI_ADDR_DESTMODE_SHIFT)
+
+#define MSI_ADDR_REDIRECTION_SHIFT      3
+#define     MSI_ADDR_REDIRECTION_CPU    (0 << MSI_ADDR_REDIRECTION_SHIFT)
+#define     MSI_ADDR_REDIRECTION_LOWPRI (1 << MSI_ADDR_REDIRECTION_SHIFT)
+
+
+static void
+msi_target_apic(unsigned int vector,
+                unsigned int dest_cpu,
+                u32 *address_hi,        /* in/out */
+                u32 *address_lo)        /* in/out */
+{
+        u32 addr = *address_lo;
+
+        addr &= MSI_ADDR_DESTID_MASK;
+        addr |= MSI_ADDR_DESTID_CPU(cpu_physical_id(dest_cpu));
+
+        *address_lo = addr;
+}
+
+static int
+msi_setup_apic(struct pci_dev *pdev,    /* unused in generic */
+                unsigned int vector,
+                u32 *address_hi,
+                u32 *address_lo,
+                u32 *data)
+{
+        unsigned long   dest_phys_id;
+
+        dest_phys_id = cpu_physical_id(first_cpu(cpu_online_map));
+
+        *address_hi = 0;
+        *address_lo =   MSI_ADDR_HEADER |
+                        MSI_ADDR_DESTMODE_PHYS |
+                        MSI_ADDR_REDIRECTION_CPU |
+                        MSI_ADDR_DESTID_CPU(dest_phys_id);
+
+        *data = MSI_DATA_TRIGGER_EDGE |
+                MSI_DATA_LEVEL_ASSERT |
+                MSI_DATA_DELIVERY_FIXED |
+                MSI_DATA_VECTOR(vector);
+
+        return 0;
+}
+
+static void
+msi_teardown_apic(unsigned int vector)
+{
+        return;         /* no-op */
+}
+
+/*
+ * Generic ops used on most IA archs/platforms.  Set with msi_register()
+ */
+
+struct msi_ops msi_apic_ops = {
+        .setup = msi_setup_apic,
+        .teardown = msi_teardown_apic,
+        .target = msi_target_apic,
+};