Add a few words of comment to all internal structures used by the driver.
Signed-off-by: Marek Szyprowski m.szyprowski@samsung.com --- drivers/iommu/exynos-iommu.c | 59 ++++++++++++++++++++++++++++---------------- 1 file changed, 38 insertions(+), 21 deletions(-)
diff --git a/drivers/iommu/exynos-iommu.c b/drivers/iommu/exynos-iommu.c index 7600861..78ce618 100644 --- a/drivers/iommu/exynos-iommu.c +++ b/drivers/iommu/exynos-iommu.c @@ -189,37 +189,54 @@ 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 list_head clients; + struct list_head clients; /* list of sysmmu_drvdata.owner_node */ };
+/* + * This structure is stored in ->priv field of generic struct iommu_domain, + * 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 this + * domain. It is usually referenced by 'domain' pointer. + */ struct exynos_iommu_domain { - struct list_head clients; /* list of sysmmu_drvdata.node */ + 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 this structure */ + spinlock_t lock; /* lock for modyfying list of clients */ spinlock_t pgtablelock; /* lock for modifying page table @ pgtable */ };
+/* + * 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; - int suspended; - spinlock_t lock; - struct iommu_domain *domain; - struct list_head domain_node; - struct list_head owner_node; - phys_addr_t pgtable; - int version; - const char *name; - dma_addr_t base; - size_t size; - struct notifier_block pm_notifier; + struct device *sysmmu; /* SYSMMU controller device */ + struct device *master; /* master device (owner of given SYSMMU) */ + 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 */ + int suspended; /* status of the controller (managed by runtime pm) */ + spinlock_t lock; /* lock for modyfying enable/disable state */ + struct iommu_domain *domain; /* domain we belong to */ + struct list_head domain_node; /* node for domain clients list */ + struct list_head owner_node; /* node for owner clients list */ + phys_addr_t pgtable; /* assigned page table structure */ + int version; /* our version */ + const char *name; /* our name from device tree */ + dma_addr_t base; /* base addres of IO address space define in DT */ + size_t size; /* size of IO address space define in DT */ + struct notifier_block pm_notifier; /* notifier for pm domain on/off */ };
static bool set_sysmmu_active(struct sysmmu_drvdata *data)