target/linux/brcm2708/patches-4.14/950-0029-clk-bcm2835-Mark-GPIO-clocks-enabled-at-boot-as-crit.patch

   1 From 08accfd44328954d33c264402730c1944f1c70fc Mon Sep 17 00:00:00 2001
   2 From: Eric Anholt <eric@anholt.net>
   3 Date: Mon, 9 May 2016 17:28:18 -0700
   4 Subject: [PATCH 029/454] clk: bcm2835: Mark GPIO clocks enabled at boot as
   5  critical.
   6
   7 These divide off of PLLD_PER and are used for the ethernet and wifi
   8 PHYs source PLLs.  Neither of them is currently represented by a phy
   9 device that would grab the clock for us.
  10
  11 This keeps other drivers from killing the networking PHYs when they
  12 disable their own clocks and trigger PLLD_PER's refcount going to 0.
  13
  14 v2: Skip marking as critical if they aren't on at boot.
  15
  16 Signed-off-by: Eric Anholt <eric@anholt.net>
  17 ---
  18  drivers/clk/bcm/clk-bcm2835.c | 9 +++++++++
  19  1 file changed, 9 insertions(+)
  20
  21 --- a/drivers/clk/bcm/clk-bcm2835.c
  22 +++ b/drivers/clk/bcm/clk-bcm2835.c
  23 @@ -1492,6 +1492,15 @@ static struct clk_hw *bcm2835_register_c
  24         init.flags = data->flags | CLK_IGNORE_UNUSED;
  25
  26         /*
  27 +        * Some GPIO clocks for ethernet/wifi PLLs are marked as
  28 +        * critical (since some platforms use them), but if the
  29 +        * firmware didn't have them turned on then they clearly
  30 +        * aren't actually critical.
  31 +        */
  32 +       if ((cprman_read(cprman, data->ctl_reg) & CM_ENABLE) == 0)
  33 +               init.flags &= ~CLK_IS_CRITICAL;
  34 +
  35 +       /*
  36          * Pass the CLK_SET_RATE_PARENT flag if we are allowed to propagate
  37          * rate changes on at least of the parents.
  38          */