aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/brcm2708/patches-4.9/0021-clk-bcm2835-Mark-GPIO-clocks-enabled-at-boot-as-crit.patch
blob: dfa312bc371a5c92a93cb6297b834544f13a5e32 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
From 599e7165ec6477139dae4f32a12e8d49d5dd8859 Mon Sep 17 00:00:00 2001
From: Eric Anholt <eric@anholt.net>
Date: Mon, 9 May 2016 17:28:18 -0700
Subject: [PATCH] clk: bcm2835: Mark GPIO clocks enabled at boot as critical.

These divide off of PLLD_PER and are used for the ethernet and wifi
PHYs source PLLs.  Neither of them is currently represented by a phy
device that would grab the clock for us.

This keeps other drivers from killing the networking PHYs when they
disable their own clocks and trigger PLLD_PER's refcount going to 0.

v2: Skip marking as critical if they aren't on at boot.

Signed-off-by: Eric Anholt <eric@anholt.net>
---
 drivers/clk/bcm/clk-bcm2835.c | 9 +++++++++
 1 file changed, 9 insertions(+)

--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -1262,6 +1262,15 @@ static struct clk_hw *bcm2835_register_c
 	init.name = data->name;
 	init.flags = data->flags | CLK_IGNORE_UNUSED;
 
+	/*
+	 * Some GPIO clocks for ethernet/wifi PLLs are marked as
+	 * critical (since some platforms use them), but if the
+	 * firmware didn't have them turned on then they clearly
+	 * aren't actually critical.
+	 */
+	if ((cprman_read(cprman, data->ctl_reg) & CM_ENABLE) == 0)
+		init.flags &= ~CLK_IS_CRITICAL;
+
 	if (data->is_vpu_clock) {
 		init.ops = &bcm2835_vpu_clock_clk_ops;
 	} else {