On Tue, Jul 07, 2026 at 12:48:57PM +0530, Nikhil Kumar Singh wrote: > Hi Mukesh, > > Thanks for reviewing the patch and for the suggestion. > I'd prefer to keep the current alignment as I find it a bit more readable. > > Thanks, > ~ Nikhil > There is a reason we keep the character limit to 80 chars. Please go through these coding guidelines.
https://docs.kernel.org/process/coding-style.html Regards, Mukesh > On 07/07/26 11:08, Mukesh Kumar Chaurasiya wrote: > > On Mon, Jul 06, 2026 at 01:57:08PM +0530, Nikhil Kumar Singh wrote: > > > The value loaded into r0 in copy_and_flush() represents the number of > > > 8-byte words processed between cache synchronization operations. > > > > > > The existing comment refers to cache line size, which can make it appear > > > that the value is a cache line size in bytes rather than a loop count. > > > Clarify the comment to explain that the loop processes 8 words (64 bytes) > > > per cache synchronization iteration, and that increasing the value would > > > skip cache maintenance for intermediate cache lines. > > > > > > This is a comment-only change with no functional impact. > > > > > > Signed-off-by: Nikhil Kumar Singh <[email protected]> > > > --- > > > arch/powerpc/kernel/head_64.S | 20 ++++++++++++-------- > > > 1 file changed, 12 insertions(+), 8 deletions(-) > > > > > > diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S > > > index 63432a33ec49..a54f6f979173 100644 > > > --- a/arch/powerpc/kernel/head_64.S > > > +++ b/arch/powerpc/kernel/head_64.S > > > @@ -713,14 +713,18 @@ p_end: .8byte _end - copy_to_here > > > _GLOBAL(copy_and_flush) > > > addi r5,r5,-8 > > > addi r6,r6,-8 > > > -4: li r0,8 /* Use the smallest common > > > */ > > > - /* denominator cache line */ > > > - /* size. This results in */ > > > - /* extra cache line flushes */ > > > - /* but operation is correct. */ > > > - /* Can't get cache line size */ > > > - /* from NACA as it is being */ > > > - /* moved too. */ > > > +4: li r0,8 /* r0 is the number of 8-byte > > > words */ > > > + /* to copy per cache sync iteration. > > > */ > > > + /* 8 words * 8 bytes = 64 bytes. 64B is > > > */ > > > + /* the current default cache line size. > > > */ > > > + /* This is a loop count, not a byte > > > */ > > > + /* count. Increasing it may skip > > > */ > > > + /* dcbst/icbi for lines in between and > > > */ > > > + /* leave stale instructions in icache. > > > */ > > > + /* This results in extra cache line > > > */ > > > + /* flushes but operation is correct. > > > */ > > > + /* Can't get cache line size from NACA > > > */ > > > + /* as it is being moved too. > > > */ > > The comment looks fine. But the alignement of the comment is still > > different from earlier. Keep the alignment same as earlier, it looks a > > little nicer. > > > > Regards, > > Mukesh > > > mtctr r0 /* put # words/line in ctr > > > */ > > > 3: addi r6,r6,8 /* copy a cache line > > > */ > > > -- > > > 2.43.5 > > > >
