target/linux/brcm2708/patches-4.9/950-0194-clk-bcm2835-Correct-the-prediv-logic.patch

   1 From a9913dccdeaabca37343d0d8b0a48cda1e434e02 Mon Sep 17 00:00:00 2001
   2 From: Phil Elwell <phil@raspberrypi.org>
   3 Date: Wed, 1 Mar 2017 16:06:53 +0000
   4 Subject: [PATCH] clk-bcm2835: Correct the prediv logic
   5
   6 If a clock has the prediv flag set, both the integer and fractional
   7 parts must be scaled when calculating the resulting frequency.
   8
   9 Signed-off-by: Phil Elwell <phil@raspberrypi.org>
  10 ---
  11  drivers/clk/bcm/clk-bcm2835.c | 4 +++-
  12  1 file changed, 3 insertions(+), 1 deletion(-)
  13
  14 --- a/drivers/clk/bcm/clk-bcm2835.c
  15 +++ b/drivers/clk/bcm/clk-bcm2835.c
  16 @@ -616,8 +616,10 @@ static unsigned long bcm2835_pll_get_rat
  17         using_prediv = cprman_read(cprman, data->ana_reg_base + 4) &
  18                 data->ana->fb_prediv_mask;
  19
  20 -       if (using_prediv)
  21 +       if (using_prediv) {
  22                 ndiv *= 2;
  23 +               fdiv *= 2;
  24 +       }
  25
  26         return bcm2835_pll_rate_from_divisors(parent_rate, ndiv, fdiv, pdiv);
  27  }