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From: Yixun Lan <dlan@gentoo.org>
To: Alex Elder <elder@riscstar.com>
Cc: Haylen Chu <heylenay@4d2.org>,
	llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev,
	Inochi Amaoto <inochiama@outlook.com>
Subject: Re: [spacemit:for-next 4/6] drivers/clk/spacemit/ccu-k1.c:241:1: error: initializer element is not a compile-time constant
Date: Tue, 15 Apr 2025 14:31:37 +0000	[thread overview]
Message-ID: <20250415143137-GYB30887@gentoo> (raw)
In-Reply-To: <564eb8e7-a4e1-49e6-a79d-da880a526540@riscstar.com>

Hi Alex,

On 09:16 Tue 15 Apr     , Alex Elder wrote:
> On 4/15/25 8:44 AM, kernel test robot wrote:
> > tree:   https://github.com/spacemit-com/linux for-next
> > head:   9ead3efbc88a21e9a1f38948cc0902518022a2e5
> > commit: e2d238ba301f25a5c8a7d490a36f9cd014d7aecc [4/6] clk: spacemit: Add clock support for SpacemiT K1 SoC
> > config: s390-allmodconfig (https://download.01.org/0day-ci/archive/20250415/202504152107.7ekGPIrF-lkp@intel.com/config)
> > compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250415/202504152107.7ekGPIrF-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/202504152107.7ekGPIrF-lkp@intel.com/
> > 
> > All errors (new ones prefixed by >>):
> 
> If I'm interpreting this right, this seems to be a problem on
> a S390 build (under COMPILE_TEST), because there is no constant
> version of the __ffs() for that architecture.  This might be the
> case on other architectures as well.
> 
> On RISC-V, this is fine.
> 
> Any recommendations on how to address this?
> 
it occur to me the __ffs() isn't really necessary, since all input
is constant value (GENMASK here), we then should know the shift..

> 
> 
> > 
> >>> drivers/clk/spacemit/ccu-k1.c:241:1: error: initializer element is not a compile-time constant
> >       241 | CCU_DDN_DEFINE(slow_uart1_14p74, pll1_d16_153p6, MPMU_SUCCR, GENMASK(28, 16), GENMASK(12, 0), 0);
> >           | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >     drivers/clk/spacemit/ccu_ddn.h:33:15: note: expanded from macro 'CCU_DDN_DEFINE'
> >        33 |         .num_shift      = __ffs(_num_mask),                                     \
> >           |                           ^~~~~~~~~~~~~~~~
> >     drivers/clk/spacemit/ccu-k1.c:242:1: error: initializer element is not a compile-time constant
> >       242 | CCU_DDN_DEFINE(slow_uart2_48, pll1_d4_614p4, MPMU_SUCCR_1, GENMASK(28, 16), GENMASK(12, 0), 0);
> >           | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> >     drivers/clk/spacemit/ccu_ddn.h:33:15: note: expanded from macro 'CCU_DDN_DEFINE'
> >        33 |         .num_shift      = __ffs(_num_mask),                                     \
> >           |                           ^~~~~~~~~~~~~~~~
> >     2 errors generated.
> > 
> > 
> > vim +241 drivers/clk/spacemit/ccu-k1.c
> > 
> >     239	
> >     240	CCU_GATE_DEFINE(slow_uart, CCU_PARENT_NAME(osc), MPMU_ACGR, BIT(1), CLK_IGNORE_UNUSED);
> >   > 241	CCU_DDN_DEFINE(slow_uart1_14p74, pll1_d16_153p6, MPMU_SUCCR, GENMASK(28, 16), GENMASK(12, 0), 0);
> >     242	CCU_DDN_DEFINE(slow_uart2_48, pll1_d4_614p4, MPMU_SUCCR_1, GENMASK(28, 16), GENMASK(12, 0), 0);
> >     243	
> > 
> 

-- 
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55

  reply	other threads:[~2025-04-15 14:31 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-04-15 13:44 [spacemit:for-next 4/6] drivers/clk/spacemit/ccu-k1.c:241:1: error: initializer element is not a compile-time constant kernel test robot
2025-04-15 14:16 ` Alex Elder
2025-04-15 14:31   ` Yixun Lan [this message]
2025-04-15 14:56     ` Haylen Chu
2025-04-15 15:16       ` Yixun Lan
2025-04-15 16:03     ` Alex Elder
2025-04-16 12:11       ` Haylen Chu
2025-04-16 12:20         ` Alex Elder

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