drivers/dma/dw-edma/dw-edma-v0-core.c:192:19: warning: unused function 'readq_ch'

[kernel test robot <lkp@intel.com>]

Hi Gustavo,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   cfb92440ee71adcc2105b0890bb01ac3cddb8507
commit: e0c1d53891c43a70c9fa85ddb3174ab5afd7e2ec dmaengine: dw-edma: Add support for the HDMA feature
date:   11 months ago
config: mips-randconfig-r001-20220221 (https://download.01.org/0day-ci/archive/20220221/202202212129.7Gipg08u-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d271fc04d5b97b12e6b797c6067d3c96a8d7470e)
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=e0c1d53891c43a70c9fa85ddb3174ab5afd7e2ec
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout e0c1d53891c43a70c9fa85ddb3174ab5afd7e2ec
        # save the config file 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 arch/mips/cavium-octeon/crypto/ arch/mips/cavium-octeon/executive/ arch/mips/kernel/ drivers/dma/dw-edma/

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

All warnings (new ones prefixed by >>):

>> drivers/dma/dw-edma/dw-edma-v0-core.c:192:19: warning: unused function 'readq_ch'
   static inline u64 readq_ch(struct dw_edma enum dw_edma_dir dir, u16 ch,
   ^
   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 - (0x00 == 0x04)); sync 0x00; .endr; .set pop; .else; ; .endif'
   clang-15: error: clang frontend command failed with exit code 70 (use -v to see invocation)
   clang version 15.0.0 (git://gitmirror/llvm_project d271fc04d5b97b12e6b797c6067d3c96a8d7470e)
   Target: mips64el-unknown-linux
   Thread model: posix
   InstalledDir: /opt/cross/clang-d271fc04d5/bin
   clang-15: note: diagnostic msg:
   Makefile arch drivers include kernel nr_bisected scripts source usr


vim +/readq_ch +192 drivers/dma/dw-edma/dw-edma-v0-core.c

04e0a39fc10f82 Gustavo Pimentel 2021-02-18  191  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18 @192  static inline u64 readq_ch(struct dw_edma *dw, enum dw_edma_dir dir, u16 ch,
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  193  			   const void __iomem *addr)
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  194  {
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  195  	u32 value;
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  196  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  197  	if (dw->mf == EDMA_MF_EDMA_LEGACY) {
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  198  		u32 viewport_sel;
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  199  		unsigned long flags;
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  200  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  201  		raw_spin_lock_irqsave(&dw->lock, flags);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  202  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  203  		viewport_sel = FIELD_PREP(EDMA_V0_VIEWPORT_MASK, ch);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  204  		if (dir == EDMA_DIR_READ)
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  205  			viewport_sel |= BIT(31);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  206  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  207  		writel(viewport_sel,
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  208  		       &(__dw_regs(dw)->type.legacy.viewport_sel));
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  209  		value = readq(addr);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  210  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  211  		raw_spin_unlock_irqrestore(&dw->lock, flags);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  212  	} else {
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  213  		value = readq(addr);
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  214  	}
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  215  
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  216  	return value;
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  217  }
04e0a39fc10f82 Gustavo Pimentel 2021-02-18  218  

:::::: The code at line 192 was first introduced by commit
:::::: 04e0a39fc10f82a71b84af73351333b184cee578 dmaengine: dw-edma: Add writeq() and readq() for 64 bits architectures

:::::: TO: Gustavo Pimentel <Gustavo.Pimentel@synopsys.com>
:::::: CC: Vinod Koul <vkoul@kernel.org>

---
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