Add cacheinfo support for OpenRISC. Currently, a few CPU cache attributes pertaining to OpenRISC processors are exposed along with other unrelated CPU attributes in the procfs file system (/proc/cpuinfo). However, a few cache attributes remain unexposed.
Provide a mechanism that the generic cacheinfo infrastructure can employ to expose these attributes via the sysfs file system. These attributes can then be exposed in /sys/devices/system/cpu/cpuX/cache/indexN. Move the implementation to pull cache attributes from the processor's registers from arch/openrisc/kernel/setup.c with a few modifications. This implementation is based on similar work done for MIPS and LoongArch. Link: https://raw.githubusercontent.com/openrisc/doc/master/openrisc-arch-1.4-rev0.pdf Signed-off-by: Sahil Siddiq <sahil...@proton.me> --- Changes from v2 -> v3: - arch/openrisc/kernel/cacheinfo.c: 1. Use new functions introduced in patch #2. 2. Address review comments regarding coding style. - arch/openrisc/kernel/setup.c: (print_cpuinfo): Don't remove detection of UPR register. arch/openrisc/kernel/Makefile | 2 +- arch/openrisc/kernel/cacheinfo.c | 104 +++++++++++++++++++++++++++++++ arch/openrisc/kernel/setup.c | 38 ----------- 3 files changed, 105 insertions(+), 39 deletions(-) create mode 100644 arch/openrisc/kernel/cacheinfo.c diff --git a/arch/openrisc/kernel/Makefile b/arch/openrisc/kernel/Makefile index 79129161f3e0..e4c7d9bdd598 100644 --- a/arch/openrisc/kernel/Makefile +++ b/arch/openrisc/kernel/Makefile @@ -7,7 +7,7 @@ extra-y := vmlinux.lds obj-y := head.o setup.o or32_ksyms.o process.o dma.o \ traps.o time.o irq.o entry.o ptrace.o signal.o \ - sys_call_table.o unwinder.o + sys_call_table.o unwinder.o cacheinfo.o obj-$(CONFIG_SMP) += smp.o sync-timer.o obj-$(CONFIG_STACKTRACE) += stacktrace.o diff --git a/arch/openrisc/kernel/cacheinfo.c b/arch/openrisc/kernel/cacheinfo.c new file mode 100644 index 000000000000..61230545e4ff --- /dev/null +++ b/arch/openrisc/kernel/cacheinfo.c @@ -0,0 +1,104 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * OpenRISC cacheinfo support + * + * Based on work done for MIPS and LoongArch. All original copyrights + * apply as per the original source declaration. + * + * OpenRISC implementation: + * Copyright (C) 2025 Sahil Siddiq <sahil...@proton.me> + */ + +#include <linux/cacheinfo.h> +#include <asm/cpuinfo.h> +#include <asm/spr.h> +#include <asm/spr_defs.h> + +static inline void ci_leaf_init(struct cacheinfo *this_leaf, enum cache_type type, + unsigned int level, struct cache_desc *cache, int cpu) +{ + this_leaf->type = type; + this_leaf->level = level; + this_leaf->coherency_line_size = cache->block_size; + this_leaf->number_of_sets = cache->sets; + this_leaf->ways_of_associativity = cache->ways; + this_leaf->size = cache->size; + cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map); +} + +int init_cache_level(unsigned int cpu) +{ + struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()]; + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); + int leaves = 0, levels = 0; + unsigned long upr = mfspr(SPR_UPR); + unsigned long iccfgr, dccfgr; + + if (!(upr & SPR_UPR_UP)) { + printk(KERN_INFO + "-- no UPR register... unable to detect configuration\n"); + return -ENOENT; + } + + if (cpu_cache_is_present(SPR_UPR_DCP)) { + dccfgr = mfspr(SPR_DCCFGR); + cpuinfo->dcache.ways = 1 << (dccfgr & SPR_DCCFGR_NCW); + cpuinfo->dcache.sets = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3); + cpuinfo->dcache.block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7); + cpuinfo->dcache.size = + cpuinfo->dcache.sets * cpuinfo->dcache.ways * cpuinfo->dcache.block_size; + leaves += 1; + printk(KERN_INFO + "-- dcache: %d bytes total, %d bytes/line, %d set(s), %d way(s)\n", + cpuinfo->dcache.size, cpuinfo->dcache.block_size, + cpuinfo->dcache.sets, cpuinfo->dcache.ways); + } else + printk(KERN_INFO "-- dcache disabled\n"); + + if (cpu_cache_is_present(SPR_UPR_ICP)) { + iccfgr = mfspr(SPR_ICCFGR); + cpuinfo->icache.ways = 1 << (iccfgr & SPR_ICCFGR_NCW); + cpuinfo->icache.sets = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3); + cpuinfo->icache.block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7); + cpuinfo->icache.size = + cpuinfo->icache.sets * cpuinfo->icache.ways * cpuinfo->icache.block_size; + leaves += 1; + printk(KERN_INFO + "-- icache: %d bytes total, %d bytes/line, %d set(s), %d way(s)\n", + cpuinfo->icache.size, cpuinfo->icache.block_size, + cpuinfo->icache.sets, cpuinfo->icache.ways); + } else + printk(KERN_INFO "-- icache disabled\n"); + + if (!leaves) + return -ENOENT; + + levels = 1; + + this_cpu_ci->num_leaves = leaves; + this_cpu_ci->num_levels = levels; + + return 0; +} + +int populate_cache_leaves(unsigned int cpu) +{ + struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[smp_processor_id()]; + struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); + struct cacheinfo *this_leaf = this_cpu_ci->info_list; + int level = 1; + + if (cpu_cache_is_present(SPR_UPR_DCP)) { + ci_leaf_init(this_leaf, CACHE_TYPE_DATA, level, &cpuinfo->dcache, cpu); + this_leaf->attributes = ((mfspr(SPR_DCCFGR) & SPR_DCCFGR_CWS) >> 8) ? + CACHE_WRITE_BACK : CACHE_WRITE_THROUGH; + this_leaf++; + } + + if (cpu_cache_is_present(SPR_UPR_ICP)) + ci_leaf_init(this_leaf, CACHE_TYPE_INST, level, &cpuinfo->icache, cpu); + + this_cpu_ci->cpu_map_populated = true; + + return 0; +} diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c index 66207cd7bb9e..caac492d045e 100644 --- a/arch/openrisc/kernel/setup.c +++ b/arch/openrisc/kernel/setup.c @@ -113,21 +113,6 @@ static void print_cpuinfo(void) return; } - if (upr & SPR_UPR_DCP) - printk(KERN_INFO - "-- dcache: %4d bytes total, %2d bytes/line, %d set(s), %d way(s)\n", - cpuinfo->dcache.size, cpuinfo->dcache.block_size, - cpuinfo->dcache.sets, cpuinfo->dcache.ways); - else - printk(KERN_INFO "-- dcache disabled\n"); - if (upr & SPR_UPR_ICP) - printk(KERN_INFO - "-- icache: %4d bytes total, %2d bytes/line, %d set(s), %d way(s)\n", - cpuinfo->icache.size, cpuinfo->icache.block_size, - cpuinfo->icache.sets, cpuinfo->icache.ways); - else - printk(KERN_INFO "-- icache disabled\n"); - if (upr & SPR_UPR_DMP) printk(KERN_INFO "-- dmmu: %4d entries, %lu way(s)\n", 1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2), @@ -155,7 +140,6 @@ static void print_cpuinfo(void) void __init setup_cpuinfo(void) { struct device_node *cpu; - unsigned long iccfgr, dccfgr; int cpu_id = smp_processor_id(); struct cpuinfo_or1k *cpuinfo = &cpuinfo_or1k[cpu_id]; @@ -163,20 +147,6 @@ void __init setup_cpuinfo(void) if (!cpu) panic("Couldn't find CPU%d in device tree...\n", cpu_id); - iccfgr = mfspr(SPR_ICCFGR); - cpuinfo->icache.ways = 1 << (iccfgr & SPR_ICCFGR_NCW); - cpuinfo->icache.sets = 1 << ((iccfgr & SPR_ICCFGR_NCS) >> 3); - cpuinfo->icache.block_size = 16 << ((iccfgr & SPR_ICCFGR_CBS) >> 7); - cpuinfo->icache.size = - cpuinfo->icache.sets * cpuinfo->icache.ways * cpuinfo->icache.block_size; - - dccfgr = mfspr(SPR_DCCFGR); - cpuinfo->dcache.ways = 1 << (dccfgr & SPR_DCCFGR_NCW); - cpuinfo->dcache.sets = 1 << ((dccfgr & SPR_DCCFGR_NCS) >> 3); - cpuinfo->dcache.block_size = 16 << ((dccfgr & SPR_DCCFGR_CBS) >> 7); - cpuinfo->dcache.size = - cpuinfo->dcache.sets * cpuinfo->dcache.ways * cpuinfo->dcache.block_size; - if (of_property_read_u32(cpu, "clock-frequency", &cpuinfo->clock_frequency)) { printk(KERN_WARNING @@ -319,14 +289,6 @@ static int show_cpuinfo(struct seq_file *m, void *v) seq_printf(m, "revision\t\t: %d\n", vr & SPR_VR_REV); } seq_printf(m, "frequency\t\t: %ld\n", loops_per_jiffy * HZ); - seq_printf(m, "dcache size\t\t: %d bytes\n", cpuinfo->dcache.size); - seq_printf(m, "dcache block size\t: %d bytes\n", - cpuinfo->dcache.block_size); - seq_printf(m, "dcache ways\t\t: %d\n", cpuinfo->dcache.ways); - seq_printf(m, "icache size\t\t: %d bytes\n", cpuinfo->icache.size); - seq_printf(m, "icache block size\t: %d bytes\n", - cpuinfo->icache.block_size); - seq_printf(m, "icache ways\t\t: %d\n", cpuinfo->icache.ways); seq_printf(m, "immu\t\t\t: %d entries, %lu ways\n", 1 << ((mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTS) >> 2), 1 + (mfspr(SPR_DMMUCFGR) & SPR_DMMUCFGR_NTW)); -- 2.48.1
