From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Jones Date: Thu, 27 Oct 2022 15:02:40 +0200 Subject: [PATCH 2/9] RISC-V: Add Zicboz detection and block size parsing In-Reply-To: <20221027130247.31634-1-ajones@ventanamicro.com> References: <20221027130247.31634-1-ajones@ventanamicro.com> Message-ID: <20221027130247.31634-3-ajones@ventanamicro.com> List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Mostly follow the same pattern as Zicbom, but leave out the toolchain checks as we plan to use the insn-def framework for the cbo.zero instruction. Signed-off-by: Andrew Jones --- arch/riscv/Kconfig | 13 +++++++++++++ arch/riscv/include/asm/cacheflush.h | 3 ++- arch/riscv/include/asm/hwcap.h | 1 + arch/riscv/kernel/cpu.c | 1 + arch/riscv/kernel/cpufeature.c | 10 ++++++++++ arch/riscv/kernel/setup.c | 2 +- arch/riscv/mm/cacheflush.c | 23 +++++++++++++++-------- 7 files changed, 43 insertions(+), 10 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 6b48a3ae9843..c20e6fa0c0b1 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -433,6 +433,19 @@ config RISCV_ISA_ZICBOM If you don't know what to do here, say Y. +config RISCV_ISA_ZICBOZ + bool "Zicboz extension support for faster zeroing of memory" + depends on !XIP_KERNEL && MMU + select RISCV_ALTERNATIVE + default y + help + Adds support to dynamically detect the presence of the ZICBOZ + extension (cbo.zero instruction) and enable its usage. + + The Zicboz extension is used for faster zeroing of memory. + + If you don't know what to do here, say Y. + config FPU bool "FPU support" default y diff --git a/arch/riscv/include/asm/cacheflush.h b/arch/riscv/include/asm/cacheflush.h index f6fbe7042f1c..5b31568cf5e6 100644 --- a/arch/riscv/include/asm/cacheflush.h +++ b/arch/riscv/include/asm/cacheflush.h @@ -43,7 +43,8 @@ void flush_icache_mm(struct mm_struct *mm, bool local); #endif /* CONFIG_SMP */ extern unsigned int riscv_cbom_block_size; -void riscv_init_cbom_blocksize(void); +extern unsigned int riscv_cboz_block_size; +void riscv_init_cbo_blocksizes(void); #ifdef CONFIG_RISCV_DMA_NONCOHERENT void riscv_noncoherent_supported(void); diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index 5d6492bde446..eaa5a972ad2d 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -45,6 +45,7 @@ #define RISCV_ISA_EXT_ZIHINTPAUSE 29 #define RISCV_ISA_EXT_SSTC 30 #define RISCV_ISA_EXT_SVINVAL 31 +#define RISCV_ISA_EXT_ZICBOZ 32 #define RISCV_ISA_EXT_ID_MAX RISCV_ISA_EXT_MAX diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index fa427bdcf773..bf969218f609 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -144,6 +144,7 @@ static struct riscv_isa_ext_data isa_ext_arr[] = { __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT), __RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM), __RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE), + __RISCV_ISA_EXT_DATA(zicboz, RISCV_ISA_EXT_ZICBOZ), __RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX), }; diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 18b9ed4df1f4..e13b3391de76 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -78,6 +78,15 @@ static bool riscv_isa_extension_check(int id) return false; } return true; + case RISCV_ISA_EXT_ZICBOZ: + if (!riscv_cboz_block_size) { + pr_err("Zicboz detected in ISA string, but no cboz-block-size found\n"); + return false; + } else if (!is_power_of_2(riscv_cboz_block_size)) { + pr_err("cboz-block-size present, but is not a power-of-2\n"); + return false; + } + return true; } return true; @@ -225,6 +234,7 @@ void __init riscv_fill_hwcap(void) SET_ISA_EXT_MAP("zihintpause", RISCV_ISA_EXT_ZIHINTPAUSE); SET_ISA_EXT_MAP("sstc", RISCV_ISA_EXT_SSTC); SET_ISA_EXT_MAP("svinval", RISCV_ISA_EXT_SVINVAL); + SET_ISA_EXT_MAP("zicboz", RISCV_ISA_EXT_ZICBOZ); } #undef SET_ISA_EXT_MAP } diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c index a07917551027..26de0d8fd23d 100644 --- a/arch/riscv/kernel/setup.c +++ b/arch/riscv/kernel/setup.c @@ -296,7 +296,7 @@ void __init setup_arch(char **cmdline_p) setup_smp(); #endif - riscv_init_cbom_blocksize(); + riscv_init_cbo_blocksizes(); riscv_fill_hwcap(); apply_boot_alternatives(); #ifdef CONFIG_RISCV_DMA_NONCOHERENT diff --git a/arch/riscv/mm/cacheflush.c b/arch/riscv/mm/cacheflush.c index f096b9966cae..208e0d58bde3 100644 --- a/arch/riscv/mm/cacheflush.c +++ b/arch/riscv/mm/cacheflush.c @@ -91,6 +91,9 @@ void flush_icache_pte(pte_t pte) unsigned int riscv_cbom_block_size; EXPORT_SYMBOL_GPL(riscv_cbom_block_size); +unsigned int riscv_cboz_block_size; +EXPORT_SYMBOL_GPL(riscv_cboz_block_size); + static void cbo_get_block_size(struct device_node *node, const char *name, u32 *blksz, unsigned long *first_hartid) @@ -113,19 +116,23 @@ static void cbo_get_block_size(struct device_node *node, } } -void riscv_init_cbom_blocksize(void) +void riscv_init_cbo_blocksizes(void) { + unsigned long cbom_hartid, cboz_hartid; + u32 cbom_blksz = 0, cboz_blksz = 0; struct device_node *node; - unsigned long cbom_hartid; - u32 probed_block_size; - probed_block_size = 0; for_each_of_cpu_node(node) { - /* set block-size for cbom extension if available */ + /* set block-size for cbom and/or cboz extension if available */ cbo_get_block_size(node, "riscv,cbom-block-size", - &probed_block_size, &cbom_hartid); + &cbom_blksz, &cbom_hartid); + cbo_get_block_size(node, "riscv,cboz-block-size", + &cboz_blksz, &cboz_hartid); } - if (probed_block_size) - riscv_cbom_block_size = probed_block_size; + if (cbom_blksz) + riscv_cbom_block_size = cbom_blksz; + + if (cboz_blksz) + riscv_cboz_block_size = cboz_blksz; } -- 2.37.3