[PATCH] iommu/rockchip: Fix "is stall active" check

John Keeping
2016-04-05T14:05:46Z

Since commit cd6438c5f844 ("iommu/rockchip: Reconstruct to support multi
slaves") rk_iommu_is_stall_active() always returns false because the
bitwise AND operates on the boolean flag promoted to an integer and a
value that is either zero or BIT(2).

Explicitly convert the right-hand value to a boolean so that both sides
are guaranteed to be either zero or one.

rk_iommu_is_paging_enabled() does not suffer from the same problem since
RK_MMU_STATUS_PAGING_ENABLED is BIT(0), but let's apply the same change
for consistency and to make it clear that it's correct without needing
to lookup the value.

Fixes: cd6438c5f844 ("iommu/rockchip: Reconstruct to support multi slaves")
Signed-off-by: John Keeping <john@metanate.com>
---
drivers/iommu/rockchip-iommu.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
index a6f593a0a29e..5710a06c3049 100644
--- a/drivers/iommu/rockchip-iommu.c
+++ b/drivers/iommu/rockchip-iommu.c
@@ -315,8 +315,8 @@ static bool rk_iommu_is_stall_active(struct rk_iommu *iommu)
int i;

for (i = 0; i < iommu->num_mmu; i++)
- active &= rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
- RK_MMU_STATUS_STALL_ACTIVE;
+ active &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
+ RK_MMU_STATUS_STALL_ACTIVE);

return active;
}
@@ -327,8 +327,8 @@ static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu)
int i;

for (i = 0; i < iommu->num_mmu; i++)
- enable &= rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
- RK_MMU_STATUS_PAGING_ENABLED;
+ enable &= !!(rk_iommu_read(iommu->bases[i], RK_MMU_STATUS) &
+ RK_MMU_STATUS_PAGING_ENABLED);

return enable;
}
--
2.8.0.rc4.238.g874082a