Re: drivers/gpu/drm/kmb/kmb_dsi.c:812:2: warning: unused function 'set_test_mode_src_osc_freq_target_low_bits'

From: Geert Uytterhoeven
Date: Tue Sep 28 2021 - 11:39:33 EST


On Tue, Sep 28, 2021 at 5:09 PM kernel test robot <lkp@xxxxxxxxx> wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 0513e464f9007b70b96740271a948ca5ab6e7dd7
> commit: ade896460e4a62f5e4a892a98d254937f6f5b64c drm: DRM_KMB_DISPLAY should depend on ARCH_KEEMBAY
> date: 11 months ago
> config: mips-randconfig-r013-20210928 (attached as .config)
> compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project dc6e8dfdfe7efecfda318d43a06fae18b40eb498)
> reproduce (this is a W=1 build):
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # install mips cross compiling tool for clang build
> # apt-get install binutils-mips-linux-gnu
> # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ade896460e4a62f5e4a892a98d254937f6f5b64c
> git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> git fetch --no-tags linus master
> git checkout ade896460e4a62f5e4a892a98d254937f6f5b64c
> # save the attached .config to linux build tree
> mkdir build_dir
> COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash drivers/gpu/drm/kmb/ drivers/net/ethernet/mellanox/mlxsw/ mm/
>
> If you fix the issue, kindly add following tag as appropriate
> Reported-by: kernel test robot <lkp@xxxxxxxxx>
>
> All warnings (new ones prefixed by >>):
>
> >> drivers/gpu/drm/kmb/kmb_dsi.c:812:2: warning: unused function 'set_test_mode_src_osc_freq_target_low_bits'
> set_test_mode_src_osc_freq_target_low_bits(struct kmb_dsi
> ^
> >> drivers/gpu/drm/kmb/kmb_dsi.c:824:2: warning: unused function 'set_test_mode_src_osc_freq_target_hi_bits'
> set_test_mode_src_osc_freq_target_hi_bits(struct kmb_dsi

These two functions are "static inline", so there should not be such
warning. Toolchain issue?

> ^
> fatal error: error in backend: Nested variants found in inline asm string: '.if ( 0x00 ) != -1)) 0x00 ) != -1)) : ($( static struct ftrace_branch_data __attribute__((__aligned__(4))) __attribute__((__section__("_ftrace_branch"))) __if_trace = $( .func = __func__, .file = "arch/mips/include/asm/barrier.h", .line = 16, $); 0x00 ) != -1)) : $))) ) && ( (1 << 0) ); .set push; .set mips64r2; .rept 1; sync 0x00; .endr; .set pop; .else; ; .endif'
> clang-14: error: clang frontend command failed with exit code 70 (use -v to see invocation)
> clang version 14.0.0 (git://gitmirror/llvm_project dc6e8dfdfe7efecfda318d43a06fae18b40eb498)
> Target: mipsel-unknown-linux
> Thread model: posix
> InstalledDir: /opt/cross/clang-dc6e8dfdfe/bin
> clang-14: note: diagnostic msg:
> Makefile arch drivers fs include kernel mm net nr_bisected scripts source usr
>
>
> vim +/set_test_mode_src_osc_freq_target_low_bits +812 drivers/gpu/drm/kmb/kmb_dsi.c
>
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 810
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 811 static inline void
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 @812 set_test_mode_src_osc_freq_target_low_bits(struct kmb_dsi *kmb_dsi,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 813 u32 dphy_no,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 814 u32 freq)
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 815 {
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 816 /* Typical rise/fall time=166, refer Table 1207 databook,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 817 * sr_osc_freq_target[7:0]
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 818 */
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 819 test_mode_send(kmb_dsi, dphy_no, TEST_CODE_SLEW_RATE_DDL_CYCLES,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 820 (freq & 0x7f));
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 821 }
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 822
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 823 static inline void
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 @824 set_test_mode_src_osc_freq_target_hi_bits(struct kmb_dsi *kmb_dsi,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 825 u32 dphy_no,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 826 u32 freq)
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 827 {
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 828 u32 data;
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 829
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 830 /* Flag this as high nibble */
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 831 data = ((freq >> 6) & 0x1f) | (1 << 7);
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 832
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 833 /* Typical rise/fall time=166, refer Table 1207 databook,
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 834 * sr_osc_freq_target[11:7]
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 835 */
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 836 test_mode_send(kmb_dsi, dphy_no, TEST_CODE_SLEW_RATE_DDL_CYCLES, data);
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 837 }
> 98521f4d4b4cb26 Anitha Chrisanthus 2020-11-04 838
>
> :::::: The code at line 812 was first introduced by commit
> :::::: 98521f4d4b4cb265374a4b1e13b41287a1960243 drm/kmb: Mipi DSI part of the display driver
>
> :::::: TO: Anitha Chrisanthus <anitha.chrisanthus@xxxxxxxxx>
> :::::: CC: Sam Ravnborg <sam@xxxxxxxxxxxx>
>
> ---
> 0-DAY CI Kernel Test Service, Intel Corporation
> https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx


Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds