summaryrefslogtreecommitdiffstats
path: root/drivers/iommu/exynos-iommu.c
diff options
context:
space:
mode:
authorMarek Szyprowski <m.szyprowski@samsung.com>2015-05-19 15:20:31 +0200
committerJoerg Roedel <jroedel@suse.de>2015-05-29 10:49:39 +0200
commit2860af3c8f7ac9e2569378653c3948c422bd30c2 (patch)
treec9d4cc68834f054e1e3e8f95c84ff39f39df8db3 /drivers/iommu/exynos-iommu.c
parentiommu/exynos: Remove excessive includes and sort others alphabetically (diff)
downloadlinux-2860af3c8f7ac9e2569378653c3948c422bd30c2.tar.xz
linux-2860af3c8f7ac9e2569378653c3948c422bd30c2.zip
iommu/exynos: Document internal structures
Add a few words of comment to all internal structures used by the driver. Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk> Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu/exynos-iommu.c')
-rw-r--r--drivers/iommu/exynos-iommu.c53
1 files changed, 35 insertions, 18 deletions
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c
index 9d9fea2156cb..f6ed59cad90b 100644
--- a/drivers/iommu/exynos-iommu.c
+++ b/drivers/iommu/exynos-iommu.c
@@ -180,32 +180,49 @@ static char *sysmmu_fault_name[SYSMMU_FAULTS_NUM] = {
"UNKNOWN FAULT"
};
-/* attached to dev.archdata.iommu of the master device */
+/*
+ * This structure is attached to dev.archdata.iommu of the master device
+ * on device add, contains a list of SYSMMU controllers defined by device tree,
+ * which are bound to given master device. It is usually referenced by 'owner'
+ * pointer.
+*/
struct exynos_iommu_owner {
- struct device *sysmmu;
+ struct device *sysmmu; /* sysmmu controller for given master */
};
+/*
+ * This structure exynos specific generalization of struct iommu_domain.
+ * It contains list of SYSMMU controllers from all master devices, which has
+ * been attached to this domain and page tables of IO address space defined by
+ * it. It is usually referenced by 'domain' pointer.
+ */
struct exynos_iommu_domain {
- struct list_head clients; /* list of sysmmu_drvdata.node */
- sysmmu_pte_t *pgtable; /* lv1 page table, 16KB */
- short *lv2entcnt; /* free lv2 entry counter for each section */
- spinlock_t lock; /* lock for this structure */
- spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
+ struct list_head clients; /* list of sysmmu_drvdata.domain_node */
+ sysmmu_pte_t *pgtable; /* lv1 page table, 16KB */
+ short *lv2entcnt; /* free lv2 entry counter for each section */
+ spinlock_t lock; /* lock for modyfying list of clients */
+ spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */
struct iommu_domain domain; /* generic domain data structure */
};
+/*
+ * This structure hold all data of a single SYSMMU controller, this includes
+ * hw resources like registers and clocks, pointers and list nodes to connect
+ * it to all other structures, internal state and parameters read from device
+ * tree. It is usually referenced by 'data' pointer.
+ */
struct sysmmu_drvdata {
- struct device *sysmmu; /* System MMU's device descriptor */
- struct device *master; /* Owner of system MMU */
- void __iomem *sfrbase;
- struct clk *clk;
- struct clk *clk_master;
- int activations;
- spinlock_t lock;
- struct exynos_iommu_domain *domain;
- struct list_head domain_node;
- phys_addr_t pgtable;
- unsigned int version;
+ struct device *sysmmu; /* SYSMMU controller device */
+ struct device *master; /* master device (owner) */
+ void __iomem *sfrbase; /* our registers */
+ struct clk *clk; /* SYSMMU's clock */
+ struct clk *clk_master; /* master's device clock */
+ int activations; /* number of calls to sysmmu_enable */
+ spinlock_t lock; /* lock for modyfying state */
+ struct exynos_iommu_domain *domain; /* domain we belong to */
+ struct list_head domain_node; /* node for domain clients list */
+ phys_addr_t pgtable; /* assigned page table structure */
+ unsigned int version; /* our version */
};
static struct exynos_iommu_domain *to_exynos_domain(struct iommu_domain *dom)