[U-Boot] [PATCH] Make kmalloc'ed memory really DMA-safe
Masahiro Yamada
yamada.masahiro at socionext.com
Fri Aug 24 10:30:15 UTC 2018
In Linux, the memory returned by kmalloc() is DMA-capable.
However, it is not true in U-Boot.
At a glance, kmalloc() in U-Boot returns address aligned with
ARCH_DMA_MINALIGN. However, it never pads the allocated memory.
This half-way house is completely useless because calling kmalloc()
and malloc() in this order causes a cache sharing problem.
Change the implementation to call malloc_cache_aligned(), which
allocates really DMA-capable memory.
Signed-off-by: Masahiro Yamada <yamada.masahiro at socionext.com>
---
lib/linux_compat.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/lib/linux_compat.c b/lib/linux_compat.c
index a936a7e..6373b44 100644
--- a/lib/linux_compat.c
+++ b/lib/linux_compat.c
@@ -1,5 +1,6 @@
#include <common.h>
+#include <memalign.h>
#include <linux/compat.h>
struct p_current cur = {
@@ -18,7 +19,7 @@ void *kmalloc(size_t size, int flags)
{
void *p;
- p = memalign(ARCH_DMA_MINALIGN, size);
+ p = malloc_cache_aligned(size);
if (flags & __GFP_ZERO)
memset(p, 0, size);
@@ -37,5 +38,5 @@ struct kmem_cache *get_mem(int element_sz)
void *kmem_cache_alloc(struct kmem_cache *obj, int flag)
{
- return memalign(ARCH_DMA_MINALIGN, obj->sz);
+ return malloc_cache_aligned(obj->sz);
}
--
2.7.4
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