dfa312bc371a5c92a93cb6297b834544f13a5e32
[openwrt/openwrt.git] / target / linux / brcm2708 / patches-4.9 / 950-0021-clk-bcm2835-Mark-GPIO-clocks-enabled-at-boot-as-crit.patch
1 From 599e7165ec6477139dae4f32a12e8d49d5dd8859 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 | 9 +++++++++
18 1 file changed, 9 insertions(+)
19
20 --- a/drivers/clk/bcm/clk-bcm2835.c
21 +++ b/drivers/clk/bcm/clk-bcm2835.c
22 @@ -1262,6 +1262,15 @@ static struct clk_hw *bcm2835_register_c
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 {