openwrtv3/target/linux/brcm2708/patches-4.4/0344-clk-Allow-clocks-to-be-marked-as-CRITICAL.patch
Álvaro Fernández Rojas 2b1c6b21b5 brcm2708: update linux 4.4 patches to latest version
As usual these patches were extracted and rebased from the raspberry pi repo:
https://github.com/raspberrypi/linux/tree/rpi-4.4.y

Also adds support for Raspberry Pi Compute Module 3 (untested).

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2016-09-10 14:54:26 +02:00

43 lines
1.5 KiB
Diff

From f782ae472861f096fb8b349c3775fbce6316826e Mon Sep 17 00:00:00 2001
From: Lee Jones <lee.jones@linaro.org>
Date: Thu, 11 Feb 2016 13:19:09 -0800
Subject: [PATCH] clk: Allow clocks to be marked as CRITICAL
Critical clocks are those which must not be gated, else undefined
or catastrophic failure would occur. Here we have chosen to
ensure the prepare/enable counts are correctly incremented, so as
not to confuse users with enabled clocks with no visible users.
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
Link: lkml.kernel.org/r/1455225554-13267-2-git-send-email-mturquette@baylibre.com
(cherry picked from commit 32b9b10961860860268961d9aad0c56a73018c37)
---
drivers/clk/clk.c | 5 +++++
include/linux/clk-provider.h | 1 +
2 files changed, 6 insertions(+)
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -2466,6 +2466,11 @@ static int __clk_init(struct device *dev
if (core->ops->init)
core->ops->init(core->hw);
+ if (core->flags & CLK_IS_CRITICAL) {
+ clk_core_prepare(core);
+ clk_core_enable(core);
+ }
+
kref_init(&core->ref);
out:
clk_prepare_unlock();
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -31,6 +31,7 @@
#define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
#define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
#define CLK_RECALC_NEW_RATES BIT(9) /* recalc rates after notifications */
+#define CLK_IS_CRITICAL BIT(11) /* do not gate, ever */
struct clk;
struct clk_hw;