clk: iproc: Fix PLL output frequency calculation

This patch affects the clocks that use fractional ndivider in their
PLL output frequency calculation. Instead of 2^20 divide factor, the
clock's ndiv integer shift was used. Fixed the bug by replacing ndiv
integer shift with 2^20 factor.

Signed-off-by: Simran Rai <ssimran@broadcom.com>
Signed-off-by: Ray Jui <rjui@broadcom.com>
Reviewed-by: Scott Branden <sbranden@broadcom.com>
Fixes: 5fe225c105fd ("clk: iproc: add initial common clock support")
Cc: <stable@vger.kernel.org> # v4.1+
Signed-off-by: Michael Turquette <mturquette@baylibre.com>

diff --git a/drivers/clk/bcm/clk-iproc-pll.c b/drivers/clk/bcm/clk-iproc-pll.c
index 2dda4e8..d679ab8 100644 (file)
--- a/drivers/clk/bcm/clk-iproc-pll.c
+++ b/drivers/clk/bcm/clk-iproc-pll.c
@@ -345,8 +345,8 @@ static unsigned long iproc_pll_recalc_rate(struct clk_hw *hw,
        struct iproc_pll *pll = clk->pll;
        const struct iproc_pll_ctrl *ctrl = pll->ctrl;
        u32 val;
-       u64 ndiv;
-       unsigned int ndiv_int, ndiv_frac, pdiv;
+       u64 ndiv, ndiv_int, ndiv_frac;
+       unsigned int pdiv;
 
        if (parent_rate == 0)
                return 0;
@@ -366,22 +366,19 @@ static unsigned long iproc_pll_recalc_rate(struct clk_hw *hw,
        val = readl(pll->pll_base + ctrl->ndiv_int.offset);
        ndiv_int = (val >> ctrl->ndiv_int.shift) &
                bit_mask(ctrl->ndiv_int.width);
-       ndiv = (u64)ndiv_int << ctrl->ndiv_int.shift;
+       ndiv = ndiv_int << 20;
 
        if (ctrl->flags & IPROC_CLK_PLL_HAS_NDIV_FRAC) {
                val = readl(pll->pll_base + ctrl->ndiv_frac.offset);
                ndiv_frac = (val >> ctrl->ndiv_frac.shift) &
                        bit_mask(ctrl->ndiv_frac.width);
-
-               if (ndiv_frac != 0)
-                       ndiv = ((u64)ndiv_int << ctrl->ndiv_int.shift) |
-                               ndiv_frac;
+               ndiv += ndiv_frac;
        }
 
        val = readl(pll->pll_base + ctrl->pdiv.offset);
        pdiv = (val >> ctrl->pdiv.shift) & bit_mask(ctrl->pdiv.width);
 
-       clk->rate = (ndiv * parent_rate) >> ctrl->ndiv_int.shift;
+       clk->rate = (ndiv * parent_rate) >> 20;
 
        if (pdiv == 0)
                clk->rate *= 2;