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net: ipa: fix table alignment requirement

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We currently have a build-time check to ensure that the minimum DMA
allocation alignment satisfies the constraint that IPA filter and
route tables must point to rules that are 128-byte aligned.

But what's really important is that the actual allocated DMA memory
has that alignment, even if the minimum is smaller than that.

Remove the BUILD_BUG_ON() call checking against minimim DMA alignment
and instead verify at rutime that the allocated memory is properly
aligned.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alex Elder 2021-03-18 13:59:29 -05:00 committed by David S. Miller
parent 3c54b7be5d
commit e5d4e96b44
1 changed files with 12 additions and 8 deletions
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20
drivers/net/ipa/ipa_table.c
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@ -118,14 +118,6 @@
/* Check things that can be validated at build time. */ /* Check things that can be validated at build time. */
static void ipa_table_validate_build(void) static void ipa_table_validate_build(void)
{ {
/* IPA hardware accesses memory 128 bytes at a time. Addresses
* referred to by entries in filter and route tables must be
* aligned on 128-byte byte boundaries. The only rule address
* ever use is the "zero rule", and it's aligned at the base
* of a coherent DMA allocation.
*/
BUILD_BUG_ON(ARCH_DMA_MINALIGN % IPA_TABLE_ALIGN);
/* Filter and route tables contain DMA addresses that refer /* Filter and route tables contain DMA addresses that refer
* to filter or route rules. But the size of a table entry * to filter or route rules. But the size of a table entry
* is 64 bits regardless of what the size of an AP DMA address * is 64 bits regardless of what the size of an AP DMA address
@ -665,6 +657,18 @@ int ipa_table_init(struct ipa *ipa)
if (!virt) if (!virt)
return -ENOMEM; return -ENOMEM;
/* We put the "zero rule" at the base of our table area. The IPA
* hardware requires rules to be aligned on a 128-byte boundary.
* Make sure the allocation satisfies this constraint.
*/
if (addr % IPA_TABLE_ALIGN) {
dev_err(dev, "table address %pad not %u-byte aligned\n",
&addr, IPA_TABLE_ALIGN);
dma_free_coherent(dev, size, virt, addr);
return -ERANGE;
}
ipa->table_virt = virt; ipa->table_virt = virt;
ipa->table_addr = addr; ipa->table_addr = addr;