clk: scmi: Fix clock rate rounding

While the do_div() helper used for rounding expects its divisor argument
to be a 32bits quantity, the currently provided divisor parameter is a
64bit value that, as a consequence, is silently truncated and a possible
source of bugs.

Fix by using the proper div64_ul helper.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-clk@vger.kernel.org
Fixes: 7a8655e19bdb ("clk: scmi: Fix the rounding of clock rate")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Florian Fainelli <florian.fainelli@broadcom.com>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20260508153300.2224715-2-cristian.marussi@arm.com
Reviewed-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Sudeep Holla <sudeep.holla@kernel.org>

diff --git a/drivers/clk/clk-scmi.c b/drivers/clk/clk-scmi.c
index 6b286ea6f1218c802d0ebb782c75a19057581c20..b6a12f3bc123c92f4bfce24babdc4e2fcb329dae 100644 (file)
--- a/drivers/clk/clk-scmi.c
+++ b/drivers/clk/clk-scmi.c
@@ -10,9 +10,9 @@
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/scmi_protocol.h>
-#include <asm/div64.h>
 
 #define NOT_ATOMIC     false
 #define ATOMIC         true
@@ -83,7 +83,7 @@ static int scmi_clk_determine_rate(struct clk_hw *hw,
 
        ftmp = req->rate - fmin;
        ftmp += clk->info->range.step_size - 1; /* to round up */
-       do_div(ftmp, clk->info->range.step_size);
+       ftmp = div64_ul(ftmp, clk->info->range.step_size);
 
        req->rate = ftmp * clk->info->range.step_size + fmin;