Commit f171abab authored by Sachin Kamat's avatar Sachin Kamat Committed by Joerg Roedel

iommu/exynos: Fix trivial typos

Fixed trivial typos and grammar to improve readability.
Changed w/a to workaround.
Signed-off-by: default avatarSachin Kamat <sachin.kamat@samsung.com>
Acked-by: default avatarRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 7d1311b9
......@@ -32,7 +32,7 @@
typedef u32 sysmmu_iova_t;
typedef u32 sysmmu_pte_t;
/* We does not consider super section mapping (16MB) */
/* We do not consider super section mapping (16MB) */
#define SECT_ORDER 20
#define LPAGE_ORDER 16
#define SPAGE_ORDER 12
......@@ -307,7 +307,7 @@ static void show_fault_information(const char *name,
static irqreturn_t exynos_sysmmu_irq(int irq, void *dev_id)
{
/* SYSMMU is in blocked when interrupt occurred. */
/* SYSMMU is in blocked state when interrupt occurred. */
struct sysmmu_drvdata *data = dev_id;
enum exynos_sysmmu_inttype itype;
sysmmu_iova_t addr = -1;
......@@ -567,8 +567,8 @@ static void sysmmu_tlb_invalidate_entry(struct device *dev, sysmmu_iova_t iova,
/*
* L2TLB invalidation required
* 4KB page: 1 invalidation
* 64KB page: 16 invalidation
* 1MB page: 64 invalidation
* 64KB page: 16 invalidations
* 1MB page: 64 invalidations
* because it is set-associative TLB
* with 8-way and 64 sets.
* 1MB page can be cached in one of all sets.
......@@ -714,7 +714,7 @@ static int exynos_iommu_domain_init(struct iommu_domain *domain)
if (!priv->lv2entcnt)
goto err_counter;
/* w/a of System MMU v3.3 to prevent caching 1MiB mapping */
/* Workaround for System MMU v3.3 to prevent caching 1MiB mapping */
for (i = 0; i < NUM_LV1ENTRIES; i += 8) {
priv->pgtable[i + 0] = ZERO_LV2LINK;
priv->pgtable[i + 1] = ZERO_LV2LINK;
......@@ -861,14 +861,14 @@ static sysmmu_pte_t *alloc_lv2entry(struct exynos_iommu_domain *priv,
pgtable_flush(sent, sent + 1);
/*
* If pretched SLPD is a fault SLPD in zero_l2_table, FLPD cache
* may caches the address of zero_l2_table. This function
* replaces the zero_l2_table with new L2 page table to write
* valid mappings.
* If pre-fetched SLPD is a faulty SLPD in zero_l2_table,
* FLPD cache may cache the address of zero_l2_table. This
* function replaces the zero_l2_table with new L2 page table
* to write valid mappings.
* Accessing the valid area may cause page fault since FLPD
* cache may still caches zero_l2_table for the valid area
* instead of new L2 page table that have the mapping
* information of the valid area
* cache may still cache zero_l2_table for the valid area
* instead of new L2 page table that has the mapping
* information of the valid area.
* Thus any replacement of zero_l2_table with other valid L2
* page table must involve FLPD cache invalidation for System
* MMU v3.3.
......@@ -963,27 +963,27 @@ static int lv2set_page(sysmmu_pte_t *pent, phys_addr_t paddr, size_t size,
/*
* *CAUTION* to the I/O virtual memory managers that support exynos-iommu:
*
* System MMU v3.x have an advanced logic to improve address translation
* System MMU v3.x has advanced logic to improve address translation
* performance with caching more page table entries by a page table walk.
* However, the logic has a bug that caching fault page table entries and System
* MMU reports page fault if the cached fault entry is hit even though the fault
* entry is updated to a valid entry after the entry is cached.
* To prevent caching fault page table entries which may be updated to valid
* entries later, the virtual memory manager should care about the w/a about the
* problem. The followings describe w/a.
* However, the logic has a bug that while caching faulty page table entries,
* System MMU reports page fault if the cached fault entry is hit even though
* the fault entry is updated to a valid entry after the entry is cached.
* To prevent caching faulty page table entries which may be updated to valid
* entries later, the virtual memory manager should care about the workaround
* for the problem. The following describes the workaround.
*
* Any two consecutive I/O virtual address regions must have a hole of 128KiB
* in maximum to prevent misbehavior of System MMU 3.x. (w/a of h/w bug)
* at maximum to prevent misbehavior of System MMU 3.x (workaround for h/w bug).
*
* Precisely, any start address of I/O virtual region must be aligned by
* Precisely, any start address of I/O virtual region must be aligned with
* the following sizes for System MMU v3.1 and v3.2.
* System MMU v3.1: 128KiB
* System MMU v3.2: 256KiB
*
* Because System MMU v3.3 caches page table entries more aggressively, it needs
* more w/a.
* - Any two consecutive I/O virtual regions must be have a hole of larger size
* than or equal size to 128KiB.
* more workarounds.
* - Any two consecutive I/O virtual regions must have a hole of size larger
* than or equal to 128KiB.
* - Start address of an I/O virtual region must be aligned by 128KiB.
*/
static int exynos_iommu_map(struct iommu_domain *domain, unsigned long l_iova,
......@@ -1061,7 +1061,8 @@ static size_t exynos_iommu_unmap(struct iommu_domain *domain,
goto err;
}
*ent = ZERO_LV2LINK; /* w/a for h/w bug in Sysmem MMU v3.3 */
/* workaround for h/w bug in System MMU v3.3 */
*ent = ZERO_LV2LINK;
pgtable_flush(ent, ent + 1);
size = SECT_SIZE;
goto done;
......
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