iommu/amd: Split amd_iommu_init function

The hardware-initializtion part of the AMD IOMMU driver is
split out into a seperate function. This function can now be
called either from amd_iommu_init() itself or any other
place if the hardware needs to be ready earlier. This will
be used to implement interrupt remapping for AMD.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index bdea288dc185c619e7e944a2959ed215e2a22c10..75653daf1de12ffd7024994d802a9bb49f154d9c 100644 (file)
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -1424,10 +1424,40 @@ static struct syscore_ops amd_iommu_syscore_ops = {
        .resume = amd_iommu_resume,
 };
 
+static void __init free_on_init_error(void)
+{
+       amd_iommu_uninit_devices();
+
+       free_pages((unsigned long)amd_iommu_pd_alloc_bitmap,
+                  get_order(MAX_DOMAIN_ID/8));
+
+       free_pages((unsigned long)amd_iommu_rlookup_table,
+                  get_order(rlookup_table_size));
+
+       free_pages((unsigned long)amd_iommu_alias_table,
+                  get_order(alias_table_size));
+
+       free_pages((unsigned long)amd_iommu_dev_table,
+                  get_order(dev_table_size));
+
+       free_iommu_all();
+
+       free_unity_maps();
+
+#ifdef CONFIG_GART_IOMMU
+       /*
+        * We failed to initialize the AMD IOMMU - try fallback to GART
+        * if possible.
+        */
+       gart_iommu_init();
+
+#endif
+}
+
 /*
- * This is the core init function for AMD IOMMU hardware in the system.
- * This function is called from the generic x86 DMA layer initialization
- * code.
+ * This is the hardware init function for AMD IOMMU in the system.
+ * This function is called either from amd_iommu_init or from the interrupt
+ * remapping setup code.
  *
  * This function basically parses the ACPI table for AMD IOMMU (IVRS)
  * three times:
@@ -1446,16 +1476,21 @@ static struct syscore_ops amd_iommu_syscore_ops = {
  *             remapping requirements parsed out of the ACPI table in
  *             this last pass.
  *
- * After that the hardware is initialized and ready to go. In the last
- * step we do some Linux specific things like registering the driver in
- * the dma_ops interface and initializing the suspend/resume support
- * functions. Finally it prints some information about AMD IOMMUs and
- * the driver state and enables the hardware.
+ * After everything is set up the IOMMUs are enabled and the necessary
+ * hotplug and suspend notifiers are registered.
  */
-static int __init amd_iommu_init(void)
+int __init amd_iommu_init_hardware(void)
 {
        int i, ret = 0;
 
+       if (!amd_iommu_detected)
+               return -ENODEV;
+
+       if (amd_iommu_dev_table != NULL) {
+               /* Hardware already initialized */
+               return 0;
+       }
+
        /*
         * First parse ACPI tables to find the largest Bus/Dev/Func
         * we need to handle. Upon this information the shared data
@@ -1472,9 +1507,8 @@ static int __init amd_iommu_init(void)
        alias_table_size   = tbl_size(ALIAS_TABLE_ENTRY_SIZE);
        rlookup_table_size = tbl_size(RLOOKUP_TABLE_ENTRY_SIZE);
 
-       ret = -ENOMEM;
-
        /* Device table - directly used by all IOMMUs */
+       ret = -ENOMEM;
        amd_iommu_dev_table = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
                                      get_order(dev_table_size));
        if (amd_iommu_dev_table == NULL)
@@ -1546,20 +1580,46 @@ static int __init amd_iommu_init(void)
 
        enable_iommus();
 
+       amd_iommu_init_notifier();
+
+       register_syscore_ops(&amd_iommu_syscore_ops);
+
+out:
+       return ret;
+
+free:
+       free_on_init_error();
+
+       return ret;
+}
+
+/*
+ * This is the core init function for AMD IOMMU hardware in the system.
+ * This function is called from the generic x86 DMA layer initialization
+ * code.
+ *
+ * The function calls amd_iommu_init_hardware() to setup and enable the
+ * IOMMU hardware if this has not happened yet. After that the driver
+ * registers for the DMA-API and for the IOMMU-API as necessary.
+ */
+static int __init amd_iommu_init(void)
+{
+       int ret = 0;
+
+       ret = amd_iommu_init_hardware();
+       if (ret)
+               goto out;
+
        if (iommu_pass_through)
                ret = amd_iommu_init_passthrough();
        else
                ret = amd_iommu_init_dma_ops();
 
        if (ret)
-               goto free_disable;
+               goto free;
 
        amd_iommu_init_api();
 
-       amd_iommu_init_notifier();
-
-       register_syscore_ops(&amd_iommu_syscore_ops);
-
        if (iommu_pass_through)
                goto out;
 
@@ -1569,39 +1629,14 @@ static int __init amd_iommu_init(void)
                printk(KERN_INFO "AMD-Vi: Lazy IO/TLB flushing enabled\n");
 
        x86_platform.iommu_shutdown = disable_iommus;
+
 out:
        return ret;
 
-free_disable:
-       disable_iommus();
-
 free:
-       amd_iommu_uninit_devices();
-
-       free_pages((unsigned long)amd_iommu_pd_alloc_bitmap,
-                  get_order(MAX_DOMAIN_ID/8));
-
-       free_pages((unsigned long)amd_iommu_rlookup_table,
-                  get_order(rlookup_table_size));
-
-       free_pages((unsigned long)amd_iommu_alias_table,
-                  get_order(alias_table_size));
-
-       free_pages((unsigned long)amd_iommu_dev_table,
-                  get_order(dev_table_size));
-
-       free_iommu_all();
-
-       free_unity_maps();
-
-#ifdef CONFIG_GART_IOMMU
-       /*
-        * We failed to initialize the AMD IOMMU - try fallback to GART
-        * if possible.
-        */
-       gart_iommu_init();
+       disable_iommus();
 
-#endif
+       free_on_init_error();
 
        goto out;
 }

diff --git a/include/linux/amd-iommu.h b/include/linux/amd-iommu.h
index ef00610837d4f9e1b556028c151df0118b89677c..15f6b9edd0b17ec30ed3cafacd5d686666279bdc 100644 (file)
--- a/include/linux/amd-iommu.h
+++ b/include/linux/amd-iommu.h
@@ -28,7 +28,7 @@ struct task_struct;
 struct pci_dev;
 
 extern int amd_iommu_detect(void);
-
+extern int amd_iommu_init_hardware(void);
 
 /**
  * amd_iommu_enable_device_erratum() - Enable erratum workaround for device