mtd: bcm47xxnflash: fix typo in freq calculation

We are supposed to mask value, not multiply it. Add some comments btw.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
index b2ab373c9eef..dc204f3a47ed 100644
--- a/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
+++ b/drivers/mtd/nand/bcm47xxnflash/ops_bcm4706.c
@@ -364,11 +364,13 @@ int bcm47xxnflash_ops_bcm4706_init(struct bcm47xxnflash *b47n)
 
         /* Configure wait counters */
         if (b47n->cc->status & BCMA_CC_CHIPST_4706_PKG_OPTION) {
-                freq = 100000000;
+                /* 400 MHz */
+                freq = 400000000 / 4;
         } else {
                 freq = bcma_chipco_pll_read(b47n->cc, 4);
-                freq = (freq * 0xFFF) >> 3;
-                freq = (freq * 25000000) >> 3;
+                freq = (freq & 0xFFF) >> 3;
+                /* Fixed reference clock 25 MHz and m = 2 */
+                freq = (freq * 25000000 / 2) / 4;
         }
         clock = freq / 1000000;
         w0 = bcm47xxnflash_ops_bcm4706_ns_to_cycle(15, clock);