1 files changed, 4 insertions, 4 deletions

diff --git a/drivers/iommu/fsl_pamu.c b/drivers/iommu/fsl_pamu.c
index b99dd88e31b9..bb446d742a2d 100644
--- a/drivers/iommu/fsl_pamu.c
+++ b/drivers/iommu/fsl_pamu.c
@@ -170,10 +170,10 @@ int pamu_disable_liodn(int liodn)
 static unsigned int map_addrspace_size_to_wse(phys_addr_t addrspace_size)
 {
         /* Bug if not a power of 2 */
-        BUG_ON(!is_power_of_2(addrspace_size));
+        BUG_ON((addrspace_size & (addrspace_size - 1)));
 
         /* window size is 2^(WSE+1) bytes */
-        return __ffs(addrspace_size) - 1;
+        return fls64(addrspace_size) - 2;
 }
 
 /* Derive the PAACE window count encoding for the subwindow count */
@@ -351,7 +351,7 @@ int pamu_config_ppaace(int liodn, phys_addr_t win_addr, phys_addr_t win_size,
         struct paace *ppaace;
         unsigned long fspi;
 
-        if (!is_power_of_2(win_size) || win_size < PAMU_PAGE_SIZE) {
+        if ((win_size & (win_size - 1)) || win_size < PAMU_PAGE_SIZE) {
                 pr_debug("window size too small or not a power of two %llx\n", win_size);
                 return -EINVAL;
         }
@@ -464,7 +464,7 @@ int pamu_config_spaace(int liodn, u32 subwin_cnt, u32 subwin,
                 return -ENOENT;
         }
 
-        if (!is_power_of_2(subwin_size) || subwin_size < PAMU_PAGE_SIZE) {
+        if ((subwin_size & (subwin_size - 1)) || subwin_size < PAMU_PAGE_SIZE) {
                 pr_debug("subwindow size out of range, or not a power of 2\n");
                 return -EINVAL;
         }