iommu/arm-smmu: Implement reserved region get/put callbacks

The get() populates the list with the MSI IOVA reserved window.

At the moment an arbitray MSI IOVA window is set at 0x8000000
of size 1MB. This will allow to report those info in iommu-group
sysfs.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Tomasz Nowicki <tomasz.nowicki@caviumnetworks.com>
Tested-by: Bharat Bhushan <bharat.bhushan@nxp.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
(cherry picked from commit f3ebee80b3131d4cdb49d39cf07b32afe40b811c)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index a60cded8a6eddf445dcb1e2b0177999c207c8a74..a354572491c8a3cb1ca0d393ad6ce72eb3b9cc0b 100644 (file)
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -281,6 +281,9 @@ enum arm_smmu_s2cr_privcfg {
 
 #define FSYNR0_WNR                     (1 << 4)
 
+#define MSI_IOVA_BASE                  0x8000000
+#define MSI_IOVA_LENGTH                        0x100000
+
 static int force_stage;
 module_param(force_stage, int, S_IRUGO);
 MODULE_PARM_DESC(force_stage,
@@ -1549,6 +1552,29 @@ static int arm_smmu_of_xlate(struct device *dev, struct of_phandle_args *args)
        return iommu_fwspec_add_ids(dev, &fwid, 1);
 }
 
+static void arm_smmu_get_resv_regions(struct device *dev,
+                                     struct list_head *head)
+{
+       struct iommu_resv_region *region;
+       int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO;
+
+       region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH,
+                                        prot, IOMMU_RESV_MSI);
+       if (!region)
+               return;
+
+       list_add_tail(&region->list, head);
+}
+
+static void arm_smmu_put_resv_regions(struct device *dev,
+                                     struct list_head *head)
+{
+       struct iommu_resv_region *entry, *next;
+
+       list_for_each_entry_safe(entry, next, head, list)
+               kfree(entry);
+}
+
 static struct iommu_ops arm_smmu_ops = {
        .capable                = arm_smmu_capable,
        .domain_alloc           = arm_smmu_domain_alloc,
@@ -1564,6 +1590,8 @@ static struct iommu_ops arm_smmu_ops = {
        .domain_get_attr        = arm_smmu_domain_get_attr,
        .domain_set_attr        = arm_smmu_domain_set_attr,
        .of_xlate               = arm_smmu_of_xlate,
+       .get_resv_regions       = arm_smmu_get_resv_regions,
+       .put_resv_regions       = arm_smmu_put_resv_regions,
        .pgsize_bitmap          = -1UL, /* Restricted during device attach */
 };