target/linux/brcm2708/patches-4.4/0346-clk-bcm2835-Mark-GPIO-clocks-enabled-at-boot-as-crit.patch

   1 From 3ee855d8520adaba936bccf377433468fb1c3ab0 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] clk: bcm2835: Mark GPIO clocks enabled at boot as critical.
   5
   6 These divide off of PLLD_PER and are used for the ethernet and wifi
   7 PHYs source PLLs.  Neither of them is currently represented by a phy
   8 device that would grab the clock for us.
   9
  10 This keeps other drivers from killing the networking PHYs when they
  11 disable their own clocks and trigger PLLD_PER's refcount going to 0.
  12
  13 v2: Skip marking as critical if they aren't on at boot.
  14
  15 Signed-off-by: Eric Anholt <eric@anholt.net>
  16 ---
  17  drivers/clk/bcm/clk-bcm2835.c | 13 ++++++++++++-
  18  1 file changed, 12 insertions(+), 1 deletion(-)
  19
  20 --- a/drivers/clk/bcm/clk-bcm2835.c
  21 +++ b/drivers/clk/bcm/clk-bcm2835.c
  22 @@ -1254,6 +1254,15 @@ static struct clk *bcm2835_register_cloc
  23         init.name = data->name;
  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         if (data->is_vpu_clock) {
  36                 init.ops = &bcm2835_vpu_clock_clk_ops;
  37         } else {
  38 @@ -1728,13 +1737,15 @@ static const struct bcm2835_clk_desc clk
  39                 .div_reg = CM_GP1DIV,
  40                 .int_bits = 12,
  41                 .frac_bits = 12,
  42 +               .flags = CLK_IS_CRITICAL,
  43                 .is_mash_clock = true),
  44         [BCM2835_CLOCK_GP2]     = REGISTER_PER_CLK(
  45                 .name = "gp2",
  46                 .ctl_reg = CM_GP2CTL,
  47                 .div_reg = CM_GP2DIV,
  48                 .int_bits = 12,
  49 -               .frac_bits = 12),
  50 +               .frac_bits = 12,
  51 +               .flags = CLK_IS_CRITICAL),
  52
  53         /* HDMI state machine */
  54         [BCM2835_CLOCK_HSM]     = REGISTER_PER_CLK(