[agraf-2.6:kvm-kho-gmem-test 26/27] kernel/time/sched_clock.c:76:49: error: call to undeclared function 'read_sysreg'; ISO C99 and later do not support implicit function declarations

[agraf-2.6:kvm-kho-gmem-test 26/27] kernel/time/sched_clock.c:76:49: error: call to undeclared function 'read_sysreg'; ISO C99 and later do not support implicit function declarations

[kernel test robot]

tree:   https://github.com/agraf/linux-2.6.git kvm-kho-gmem-test
head:   9a58862a298a63bad21d05191e28b857063bb9dc
commit: 12b2509463b155fec805d7fb2ecbef3aafbd2414 [26/27] XXX arm: make early time stamps contiguous
config: mips-vocore2_defconfig (https://download.01.org/0day-ci/archive/20240505/202405050219.81JETL6w-lkp@intel.com/config)
compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240505/202405050219.81JETL6w-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202405050219.81JETL6w-lkp@intel.com/

All errors (new ones prefixed by >>):

>> kernel/time/sched_clock.c:76:49: error: call to undeclared function 'read_sysreg'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
                   clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
                                                                 ^
   kernel/time/sched_clock.c:76:61: error: use of undeclared identifier 'cntfrq_el0'
                   clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
                                                                             ^
   kernel/time/sched_clock.c:183:27: warning: variable 'new_epoch' set but not used [-Wunused-but-set-variable]
           u64 res, wrap, new_mask, new_epoch, cyc, ns;
                                    ^
   kernel/time/sched_clock.c:183:43: warning: variable 'ns' set but not used [-Wunused-but-set-variable]
           u64 res, wrap, new_mask, new_epoch, cyc, ns;
                                                    ^
   2 warnings and 2 errors generated.


vim +/read_sysreg +76 kernel/time/sched_clock.c

    69	
    70	static void cd_early_init(void)
    71	{
    72		static bool is_initialized;
    73		struct clock_read_data *rd = &cd.read_data[0];
    74	
    75		if (!is_initialized) {
  > 76			clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
    77			is_initialized = true;
    78		}
    79	}
    80	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

[agraf-2.6:kvm-kho-gmem-test 26/27] kernel/time/sched_clock.c:76:49: error: call to undeclared function 'read_sysreg'; ISO C99 and later do not support implicit function declarations

[kernel test robot]

tree:   https://github.com/agraf/linux-2.6.git kvm-kho-gmem-test
head:   9a58862a298a63bad21d05191e28b857063bb9dc
commit: 12b2509463b155fec805d7fb2ecbef3aafbd2414 [26/27] XXX arm: make early time stamps contiguous
config: arm-allnoconfig (https://download.01.org/0day-ci/archive/20240505/202405050255.uiq0NPjq-lkp@intel.com/config)
compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 37ae4ad0eef338776c7e2cffb3896153d43dcd90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240505/202405050255.uiq0NPjq-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202405050255.uiq0NPjq-lkp@intel.com/

All errors (new ones prefixed by >>):

>> kernel/time/sched_clock.c:76:49: error: call to undeclared function 'read_sysreg'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
      76 |                 clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
         |                                                               ^
>> kernel/time/sched_clock.c:76:61: error: use of undeclared identifier 'cntfrq_el0'
      76 |                 clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
         |                                                                           ^
   kernel/time/sched_clock.c:183:27: warning: variable 'new_epoch' set but not used [-Wunused-but-set-variable]
     183 |         u64 res, wrap, new_mask, new_epoch, cyc, ns;
         |                                  ^
   kernel/time/sched_clock.c:183:43: warning: variable 'ns' set but not used [-Wunused-but-set-variable]
     183 |         u64 res, wrap, new_mask, new_epoch, cyc, ns;
         |                                                  ^
   2 warnings and 2 errors generated.


vim +/read_sysreg +76 kernel/time/sched_clock.c

    69	
    70	static void cd_early_init(void)
    71	{
    72		static bool is_initialized;
    73		struct clock_read_data *rd = &cd.read_data[0];
    74	
    75		if (!is_initialized) {
  > 76			clocks_calc_mult_shift(&rd->mult, &rd->shift, read_sysreg(cntfrq_el0), NSEC_PER_SEC, 600);
    77			is_initialized = true;
    78		}
    79	}
    80	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki