From mboxrd@z Thu Jan 1 00:00:00 1970 From: Conor Dooley Date: Thu, 13 Oct 2022 21:05:33 +0100 Subject: [PATCH v2] RISC-V: KVM: Fix compilation without RISCV_ISA_ZICBOM In-Reply-To: <20221013143931.vc662dbaboozjygy@kamzik> References: <20221013134217.1850349-1-ajones@ventanamicro.com> <20221013143931.vc662dbaboozjygy@kamzik> Message-ID: List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit On Thu, Oct 13, 2022 at 04:39:31PM +0200, Andrew Jones wrote: > On Thu, Oct 13, 2022 at 03:21:06PM +0100, Conor Dooley wrote: > > On Thu, Oct 13, 2022 at 03:42:17PM +0200, Andrew Jones wrote: > > > > > RISC-V: KVM: Fix compilation without RISCV_ISA_ZICBOM > > > > nit: I know that this is what it fixes, but I think the commit subject > > is a little misleading when it doesnt touch arch/riscv/kvm & has some > > meaning for non-kvm too. > > Yeah, in hindsight I probably should have just dropped the "RISC-V: KVM: > Fix compilation without RISCV_ISA_ZICBOM" patch and rebased and resent > Anup's move patch. I still can, if that's what people would prefer. I'd image that that can be done at application time? idk what I'd go for though, I am sick so my heads a little groggy. Say along the lines of "RISC-V: make cbom blocksize info unconditionally available"? Feel free to hate that Drew... Conor. > > Thanks, > drew > > > > > > > riscv_cbom_block_size and riscv_init_cbom_blocksize() should always > > > be available and riscv_init_cbom_blocksize() should always be invoked > > > > Yup, I like where this is going... > > > > > even when compiling without RISCV_ISA_ZICBOM enabled. This > > > is because disabling RISCV_ISA_ZICBOM means "don't use zicbom > > > instructions in the kernel" not "pretend there isn't zicbom, even > > > when there is". When zicbom is available, whether the kernel enables > > > its use with RISCV_ISA_ZICBOM or not, KVM will offer it to guests. > > > > ...right, I'll take your word for this part. You're the kvm people :) > > > > > Ensure we can build KVM and that the block size is initialized even > > > when compiling without RISCV_ISA_ZICBOM. > > > > > > Fixes: 8f7e001e0325 ("RISC-V: Clean up the Zicbom block size probing") > > > Reported-by: kernel test robot > > > Signed-off-by: Andrew Jones > > > > Is cacheflush.c the "right" place for it? idk. But shaving that yak is a > > waste of time imo. I like the unconditional availability & if ZICBOM is > > off in the kernel I figure it should not matter that we set the > > blocksize. > > > > Reviewed-by: Conor Dooley > > > > > --- > > > arch/riscv/include/asm/cacheflush.h | 8 ------ > > > arch/riscv/mm/cacheflush.c | 38 ++++++++++++++++++++++++++ > > > arch/riscv/mm/dma-noncoherent.c | 41 ----------------------------- > > > 3 files changed, 38 insertions(+), 49 deletions(-) > > > > > > diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h > > > index 273ece6b622f..1470e556cdb1 100644 > > > --- a/arch/riscv/include/asm/cacheflush.h > > > +++ b/arch/riscv/include/asm/cacheflush.h > > > @@ -42,16 +42,8 @@ void flush_icache_mm(struct mm_struct *mm, bool local); > > > > > > #endif /* CONFIG_SMP */ > > > > > > -/* > > > - * The T-Head CMO errata internally probe the CBOM block size, but otherwise > > > - * don't depend on Zicbom. > > > - */ > > > extern unsigned int riscv_cbom_block_size; > > > -#ifdef CONFIG_RISCV_ISA_ZICBOM > > > void riscv_init_cbom_blocksize(void); > > > -#else > > > -static inline void riscv_init_cbom_blocksize(void) { } > > > -#endif > > > > > > #ifdef CONFIG_RISCV_DMA_NONCOHERENT > > > void riscv_noncoherent_supported(void); > > > diff --git a/arch/riscv/mm/cacheflush.c b/arch/riscv/mm/cacheflush.c > > > index 6cb7d96ad9c7..8525f4a2d598 100644 > > > --- a/arch/riscv/mm/cacheflush.c > > > +++ b/arch/riscv/mm/cacheflush.c > > > @@ -3,6 +3,7 @@ > > > * Copyright (C) 2017 SiFive > > > */ > > > > > > +#include > > > #include > > > > > > #ifdef CONFIG_SMP > > > @@ -86,3 +87,40 @@ void flush_icache_pte(pte_t pte) > > > flush_icache_all(); > > > } > > > #endif /* CONFIG_MMU */ > > > + > > > +unsigned int riscv_cbom_block_size; > > > +EXPORT_SYMBOL(riscv_cbom_block_size); > > > + > > > +void riscv_init_cbom_blocksize(void) > > > +{ > > > + struct device_node *node; > > > + unsigned long cbom_hartid; > > > + u32 val, probed_block_size; > > > + int ret; > > > + > > > + probed_block_size = 0; > > > + for_each_of_cpu_node(node) { > > > + unsigned long hartid; > > > + > > > + ret = riscv_of_processor_hartid(node, &hartid); > > > + if (ret) > > > + continue; > > > + > > > + /* set block-size for cbom extension if available */ > > > + ret = of_property_read_u32(node, "riscv,cbom-block-size", &val); > > > + if (ret) > > > + continue; > > > + > > > + if (!probed_block_size) { > > > + probed_block_size = val; > > > + cbom_hartid = hartid; > > > + } else { > > > + if (probed_block_size != val) > > > + pr_warn("cbom-block-size mismatched between harts %lu and %lu\n", > > > + cbom_hartid, hartid); > > > + } > > > + } > > > + > > > + if (probed_block_size) > > > + riscv_cbom_block_size = probed_block_size; > > > +} > > > diff --git a/arch/riscv/mm/dma-noncoherent.c b/arch/riscv/mm/dma-noncoherent.c > > > index b0add983530a..d919efab6eba 100644 > > > --- a/arch/riscv/mm/dma-noncoherent.c > > > +++ b/arch/riscv/mm/dma-noncoherent.c > > > @@ -8,13 +8,8 @@ > > > #include > > > #include > > > #include > > > -#include > > > -#include > > > #include > > > > > > -unsigned int riscv_cbom_block_size; > > > -EXPORT_SYMBOL_GPL(riscv_cbom_block_size); > > > - > > > static bool noncoherent_supported; > > > > > > void arch_sync_dma_for_device(phys_addr_t paddr, size_t size, > > > @@ -77,42 +72,6 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, > > > dev->dma_coherent = coherent; > > > } > > > > > > -#ifdef CONFIG_RISCV_ISA_ZICBOM > > > -void riscv_init_cbom_blocksize(void) > > > -{ > > > - struct device_node *node; > > > - unsigned long cbom_hartid; > > > - u32 val, probed_block_size; > > > - int ret; > > > - > > > - probed_block_size = 0; > > > - for_each_of_cpu_node(node) { > > > - unsigned long hartid; > > > - > > > - ret = riscv_of_processor_hartid(node, &hartid); > > > - if (ret) > > > - continue; > > > - > > > - /* set block-size for cbom extension if available */ > > > - ret = of_property_read_u32(node, "riscv,cbom-block-size", &val); > > > - if (ret) > > > - continue; > > > - > > > - if (!probed_block_size) { > > > - probed_block_size = val; > > > - cbom_hartid = hartid; > > > - } else { > > > - if (probed_block_size != val) > > > - pr_warn("cbom-block-size mismatched between harts %lu and %lu\n", > > > - cbom_hartid, hartid); > > > - } > > > - } > > > - > > > - if (probed_block_size) > > > - riscv_cbom_block_size = probed_block_size; > > > -} > > > -#endif > > > - > > > void riscv_noncoherent_supported(void) > > > { > > > WARN(!riscv_cbom_block_size, > > > -- > > > 2.37.3 > > > > > > > > > _______________________________________________ > > > linux-riscv mailing list > > > linux-riscv at lists.infradead.org > > > http://lists.infradead.org/mailman/listinfo/linux-riscv > > _______________________________________________ > linux-riscv mailing list > linux-riscv at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv