[PATCH] clk: bcm2835: fix bcm2835_clock_choose_div

From: Stefan Wahren <stefan.wahren@i2se.com>
To: Florian Fainelli <f.fainelli@gmail.com>,
	Ray Jui <rjui@broadcom.com>,
	Scott Branden <sbranden@broadcom.com>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>
Cc: bcm-kernel-feedback-list@broadcom.com,
	Maxime Ripard <maxime@cerno.tech>,
	linux-clk@vger.kernel.org, linux-rpi-kernel@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,
	Stefan Wahren <stefan.wahren@i2se.com>
Subject: [PATCH] clk: bcm2835: fix bcm2835_clock_choose_div
Date: Thu, 28 Apr 2022 20:30:10 +0200	[thread overview]
Message-ID: <20220428183010.1635248-1-stefan.wahren@i2se.com> (raw)

The commit 09e3b18ca5de ("clk: bcm2835: Remove unused variable")
accidentially breaks the behavior of bcm2835_clock_choose_div() and
booting of Raspberry Pi. The removed do_div macro call had side effects,
so we need to restore it.

Fixes: 09e3b18ca5de ("clk: bcm2835: Remove unused variable")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/clk/bcm/clk-bcm2835.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
index 3ad20e75fd23..48a1eb9f2d55 100644
--- a/drivers/clk/bcm/clk-bcm2835.c
+++ b/drivers/clk/bcm/clk-bcm2835.c
@@ -941,6 +941,7 @@ static u32 bcm2835_clock_choose_div(struct clk_hw *hw,
 	u64 temp = (u64)parent_rate << CM_DIV_FRAC_BITS;
 	u32 div, mindiv, maxdiv;
 
+	do_div(temp, rate);
 	div = temp;
 	div &= ~unused_frac_mask;
 
-- 
2.25.1

