iommu/vt-d: Make intr-remapping initialization generic

This patch introduces irq_remap_ops to hold implementation
specific function pointer to handle interrupt remapping. As
the first part the initialization functions for VT-d are
converted to these ops.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/drivers/iommu/intr_remapping.c b/drivers/iommu/intr_remapping.c
new file mode 100644
index 000000000000..670c69a80afd
--- /dev/null
+++ b/drivers/iommu/intr_remapping.c
@@ -0,0 +1,76 @@
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+
+#include "intr_remapping.h"
+
+int intr_remapping_enabled;
+
+int disable_intremap;
+int disable_sourceid_checking;
+int no_x2apic_optout;
+
+static struct irq_remap_ops *remap_ops;
+
+static __init int setup_nointremap(char *str)
+{
+        disable_intremap = 1;
+        return 0;
+}
+early_param("nointremap", setup_nointremap);
+
+static __init int setup_intremap(char *str)
+{
+        if (!str)
+                return -EINVAL;
+
+        while (*str) {
+                if (!strncmp(str, "on", 2))
+                        disable_intremap = 0;
+                else if (!strncmp(str, "off", 3))
+                        disable_intremap = 1;
+                else if (!strncmp(str, "nosid", 5))
+                        disable_sourceid_checking = 1;
+                else if (!strncmp(str, "no_x2apic_optout", 16))
+                        no_x2apic_optout = 1;
+
+                str += strcspn(str, ",");
+                while (*str == ',')
+                        str++;
+        }
+
+        return 0;
+}
+early_param("intremap", setup_intremap);
+
+void __init setup_intr_remapping(void)
+{
+        remap_ops = &intel_irq_remap_ops;
+}
+
+int intr_remapping_supported(void)
+{
+        if (disable_intremap)
+                return 0;
+
+        if (!remap_ops || !remap_ops->supported)
+                return 0;
+
+        return remap_ops->supported();
+}
+
+int __init intr_hardware_init(void)
+{
+        if (!remap_ops || !remap_ops->hardware_init)
+                return -ENODEV;
+
+        return remap_ops->hardware_init();
+}
+
+int __init intr_hardware_enable(void)
+{
+        if (!remap_ops || !remap_ops->hardware_enable)
+                return -ENODEV;
+
+        return remap_ops->hardware_enable();
+}