Hi William,

I love your patch! Yet something to improve:

[auto build test ERROR on 5ffeb17c0d3dd44704b4aee83e297ec07666e4d6]

url:    https://github.com/0day-ci/linux/commits/William-Breathitt-Gray/Introduce-the-Counter-character-device-interface/20210827-115154
base:   5ffeb17c0d3dd44704b4aee83e297ec07666e4d6
config: i386-randconfig-c001-20210827 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/4eb2e2f3fe9da9dddf9d8bbb82ff16b1329131ce
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review William-Breathitt-Gray/Introduce-the-Counter-character-device-interface/20210827-115154
        git checkout 4eb2e2f3fe9da9dddf9d8bbb82ff16b1329131ce
        # save the attached .config to linux build tree
        mkdir build_dir
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   ld: drivers/counter/intel-qep.o: in function `intel_qep_spike_filter_ns_write':
>> drivers/counter/intel-qep.c:290: undefined reference to `__udivdi3'


vim +290 drivers/counter/intel-qep.c

b711f687a1c1c1 Jarkko Nikula          2021-06-02  275  
4eb2e2f3fe9da9 William Breathitt Gray 2021-08-27  276  static int intel_qep_spike_filter_ns_write(struct counter_device *counter,
b711f687a1c1c1 Jarkko Nikula          2021-06-02  277  					   struct counter_count *count,
4eb2e2f3fe9da9 William Breathitt Gray 2021-08-27  278  					   u64 length)
b711f687a1c1c1 Jarkko Nikula          2021-06-02  279  {
b711f687a1c1c1 Jarkko Nikula          2021-06-02  280  	struct intel_qep *qep = counter->priv;
4eb2e2f3fe9da9 William Breathitt Gray 2021-08-27  281  	u32 reg;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  282  	bool enable;
4eb2e2f3fe9da9 William Breathitt Gray 2021-08-27  283  	int ret = 0;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  284  
b711f687a1c1c1 Jarkko Nikula          2021-06-02  285  	/*
b711f687a1c1c1 Jarkko Nikula          2021-06-02  286  	 * Spike filter length is (MAX_COUNT + 2) clock periods.
b711f687a1c1c1 Jarkko Nikula          2021-06-02  287  	 * Disable filter when userspace writes 0, enable for valid
b711f687a1c1c1 Jarkko Nikula          2021-06-02  288  	 * nanoseconds values and error out otherwise.
b711f687a1c1c1 Jarkko Nikula          2021-06-02  289  	 */
b711f687a1c1c1 Jarkko Nikula          2021-06-02 @290  	length /= INTEL_QEP_CLK_PERIOD_NS;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  291  	if (length == 0) {
b711f687a1c1c1 Jarkko Nikula          2021-06-02  292  		enable = false;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  293  		length = 0;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  294  	} else if (length >= 2) {
b711f687a1c1c1 Jarkko Nikula          2021-06-02  295  		enable = true;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  296  		length -= 2;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  297  	} else {
b711f687a1c1c1 Jarkko Nikula          2021-06-02  298  		return -EINVAL;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  299  	}
b711f687a1c1c1 Jarkko Nikula          2021-06-02  300  
b711f687a1c1c1 Jarkko Nikula          2021-06-02  301  	if (length > INTEL_QEPFLT_MAX_COUNT(length))
e2ff3198c580a3 William Breathitt Gray 2021-08-03  302  		return -ERANGE;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  303  
b711f687a1c1c1 Jarkko Nikula          2021-06-02  304  	mutex_lock(&qep->lock);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  305  	if (qep->enabled) {
b711f687a1c1c1 Jarkko Nikula          2021-06-02  306  		ret = -EBUSY;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  307  		goto out;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  308  	}
b711f687a1c1c1 Jarkko Nikula          2021-06-02  309  
b711f687a1c1c1 Jarkko Nikula          2021-06-02  310  	pm_runtime_get_sync(qep->dev);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  311  	reg = intel_qep_readl(qep, INTEL_QEPCON);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  312  	if (enable)
b711f687a1c1c1 Jarkko Nikula          2021-06-02  313  		reg |= INTEL_QEPCON_FLT_EN;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  314  	else
b711f687a1c1c1 Jarkko Nikula          2021-06-02  315  		reg &= ~INTEL_QEPCON_FLT_EN;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  316  	intel_qep_writel(qep, INTEL_QEPFLT, length);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  317  	intel_qep_writel(qep, INTEL_QEPCON, reg);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  318  	pm_runtime_put(qep->dev);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  319  
b711f687a1c1c1 Jarkko Nikula          2021-06-02  320  out:
b711f687a1c1c1 Jarkko Nikula          2021-06-02  321  	mutex_unlock(&qep->lock);
b711f687a1c1c1 Jarkko Nikula          2021-06-02  322  	return ret;
b711f687a1c1c1 Jarkko Nikula          2021-06-02  323  }
b711f687a1c1c1 Jarkko Nikula          2021-06-02  324  

---
0-DAY CI Kernel Test Service, Intel Corporation
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