linux-kernel - [PATCH -next] drm/nouveau/clk: Use plain "/" for 32-bit division

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1423065755-19337-1-git-send-email-geert@linux-m68k.org>
Date:	Wed,  4 Feb 2015 17:02:35 +0100
From:	Geert Uytterhoeven <geert@...ux-m68k.org>
To:	David Airlie <airlied@...ux.ie>,
	Alexandre Courbot <acourbot@...dia.com>
Cc:	dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
	linux-next@...r.kernel.org,
	Geert Uytterhoeven <geert@...ux-m68k.org>
Subject: [PATCH -next] drm/nouveau/clk: Use plain "/" for 32-bit division

On 32-bit platforms using asm-generic/div64.h:

drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c: In function 'gk20a_pllg_calc_rate':
drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c:147:79: warning: comparison of distinct pointer types lacks a cast
  do_div(rate, divider);
                                                                               ^
drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c:147:2: warning: right shift count >= width of type
  do_div(rate, divider);
  ^
drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c:147:238: warning: passing argument 1 of '__div64_32' from incompatible pointer type
  do_div(rate, divider);
                                                                                                                                                                                                                                              ^
In file included from arch/parisc/include/generated/asm/div64.h:1:0,
                 from include/linux/kernel.h:124,
                 from include/linux/list.h:8,
                 from include/linux/preempt.h:10,
                 from include/linux/spinlock.h:50,
                 from include/linux/mmzone.h:7,
                 from include/linux/gfp.h:5,
                 from include/linux/slab.h:14,
                 from drivers/gpu/drm/nouveau/include/nvif/os.h:5,
                 from drivers/gpu/drm/nouveau/include/nvkm/core/os.h:3,
                 from drivers/gpu/drm/nouveau/include/nvkm/core/object.h:3,
                 from drivers/gpu/drm/nouveau/include/nvkm/core/subdev.h:3,
                 from drivers/gpu/drm/nouveau/include/nvkm/subdev/clk.h:3,
                 from drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c:25:
include/asm-generic/div64.h:35:17: note: expected 'uint64_t *' but argument is of type 'u32 *'
 extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
                 ^

do_div() is meant for 64-bit by 32-bit division, but both the dividend
and divisor are 32-bit here. Hence use plain "/" instead.

Signed-off-by: Geert Uytterhoeven <geert@...ux-m68k.org>
---
Compile-tested only.

parisc/allmodconfig:
http://kisskb.ellerman.id.au/kisskb/buildresult/12358386/
---
 drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c
index 65c532742b08d1c6..022595876ea4dc85 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/clk/gk20a.c
@@ -144,9 +144,8 @@ gk20a_pllg_calc_rate(struct gk20a_clk_priv *priv)
 
 	rate = priv->parent_rate * priv->n;
 	divider = priv->m * pl_to_div[priv->pl];
-	do_div(rate, divider);
 
-	return rate / 2;
+	return rate / divider / 2;
 }
 
 static int
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/