[PATCH 4/4] OMAP:IOMMU:flush L1 and L2 caches

From: Ramesh Gupta G
Date: Fri Jun 15 2012 - 07:16:46 EST


IOMMU need to make sure that data in L1 and L2 caches
is visible to the MMU hardware whenever the pagetables are
updated. The current code only takes care of L1 cache using
assembly.Added code to take care of both L1 and L2 caches
using a new L1 cache flush function and the outer cache function.

Signed-off-by: Ramesh Gupta G <grgupta@xxxxxx>
---
drivers/iommu/omap-iommu.c | 26 +++++++++-----------------
1 files changed, 9 insertions(+), 17 deletions(-)

diff --git a/drivers/iommu/omap-iommu.c b/drivers/iommu/omap-iommu.c
index 6899dcd..6344fbc 100644
--- a/drivers/iommu/omap-iommu.c
+++ b/drivers/iommu/omap-iommu.c
@@ -469,22 +469,14 @@ EXPORT_SYMBOL_GPL(omap_foreach_iommu_device);
*/
static void flush_iopgd_range(u32 *first, u32 *last)
{
- /* FIXME: L2 cache should be taken care of if it exists */
- do {
- asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pgd"
- : : "r" (first));
- first += L1_CACHE_BYTES / sizeof(*first);
- } while (first <= last);
+ flush_mem(first, last);
+ outer_flush_range(virt_to_phys(first), virt_to_phys(last));
}

static void flush_iopte_range(u32 *first, u32 *last)
{
- /* FIXME: L2 cache should be taken care of if it exists */
- do {
- asm("mcr p15, 0, %0, c7, c10, 1 @ flush_pte"
- : : "r" (first));
- first += L1_CACHE_BYTES / sizeof(*first);
- } while (first <= last);
+ flush_mem(first, last);
+ outer_flush_range(virt_to_phys(first), virt_to_phys(last));
}

static void iopte_free(u32 *iopte)
@@ -513,7 +505,7 @@ static u32 *iopte_alloc(struct omap_iommu *obj,
u32 *iopgd, u32 da)
return ERR_PTR(-ENOMEM);

*iopgd = virt_to_phys(iopte) | IOPGD_TABLE;
- flush_iopgd_range(iopgd, iopgd);
+ flush_iopgd_range(iopgd, iopgd + 1);

dev_vdbg(obj->dev, "%s: a new pte:%p\n", __func__, iopte);
} else {
@@ -542,7 +534,7 @@ static int iopgd_alloc_section(struct omap_iommu
*obj, u32 da, u32 pa, u32 prot)
}

*iopgd = (pa & IOSECTION_MASK) | prot | IOPGD_SECTION;
- flush_iopgd_range(iopgd, iopgd);
+ flush_iopgd_range(iopgd, iopgd + 1);
return 0;
}

@@ -559,7 +551,7 @@ static int iopgd_alloc_super(struct omap_iommu
*obj, u32 da, u32 pa, u32 prot)

for (i = 0; i < 16; i++)
*(iopgd + i) = (pa & IOSUPER_MASK) | prot | IOPGD_SUPER;
- flush_iopgd_range(iopgd, iopgd + 15);
+ flush_iopgd_range(iopgd, iopgd + 16);
return 0;
}

@@ -700,7 +692,7 @@ static size_t iopgtable_clear_entry_core(struct
omap_iommu *obj, u32 da)
}
bytes *= nent;
memset(iopte, 0, nent * sizeof(*iopte));
- flush_iopte_range(iopte, iopte + (nent - 1) * sizeof(*iopte));
+ flush_iopte_range(iopte, iopte + nent * sizeof(*iopte));

/*
* do table walk to check if this table is necessary or not
@@ -722,7 +714,7 @@ static size_t iopgtable_clear_entry_core(struct
omap_iommu *obj, u32 da)
bytes *= nent;
}
memset(iopgd, 0, nent * sizeof(*iopgd));
- flush_iopgd_range(iopgd, iopgd + (nent - 1) * sizeof(*iopgd));
+ flush_iopgd_range(iopgd, iopgd + nent * sizeof(*iopgd));
out:
return bytes;
}
--
1.7.0.4


--
regards
Ramesh Gupta G
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