Re: [PATCH 4/4] powerpc/64: reuse PPC32 static inline flush_dcache_range()

From: Michael Ellerman
Date: Sun Jul 07 2019 - 21:19:49 EST


On Tue, 2019-05-14 at 09:05:16 UTC, Christophe Leroy wrote:
> This patch drops the assembly PPC64 version of flush_dcache_range()
> and re-uses the PPC32 static inline version.
>
> With GCC 8.1, the following code is generated:
>
> void flush_test(unsigned long start, unsigned long stop)
> {
> flush_dcache_range(start, stop);
> }
>
> 0000000000000130 <.flush_test>:
> 130: 3d 22 00 00 addis r9,r2,0
> 132: R_PPC64_TOC16_HA .data+0x8
> 134: 81 09 00 00 lwz r8,0(r9)
> 136: R_PPC64_TOC16_LO .data+0x8
> 138: 3d 22 00 00 addis r9,r2,0
> 13a: R_PPC64_TOC16_HA .data+0xc
> 13c: 80 e9 00 00 lwz r7,0(r9)
> 13e: R_PPC64_TOC16_LO .data+0xc
> 140: 7d 48 00 d0 neg r10,r8
> 144: 7d 43 18 38 and r3,r10,r3
> 148: 7c 00 04 ac hwsync
> 14c: 4c 00 01 2c isync
> 150: 39 28 ff ff addi r9,r8,-1
> 154: 7c 89 22 14 add r4,r9,r4
> 158: 7c 83 20 50 subf r4,r3,r4
> 15c: 7c 89 3c 37 srd. r9,r4,r7
> 160: 41 82 00 1c beq 17c <.flush_test+0x4c>
> 164: 7d 29 03 a6 mtctr r9
> 168: 60 00 00 00 nop
> 16c: 60 00 00 00 nop
> 170: 7c 00 18 ac dcbf 0,r3
> 174: 7c 63 42 14 add r3,r3,r8
> 178: 42 00 ff f8 bdnz 170 <.flush_test+0x40>
> 17c: 7c 00 04 ac hwsync
> 180: 4c 00 01 2c isync
> 184: 4e 80 00 20 blr
> 188: 60 00 00 00 nop
> 18c: 60 00 00 00 nop
>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/22e9c88d486a0536d337d6e0973968be0a4cd4b2

cheers