arch/arm/kernel/cacheinfo.c

Source file repositories/reference/linux-study-clean/arch/arm/kernel/cacheinfo.c

File Facts

System
Linux kernel
Corpus path
arch/arm/kernel/cacheinfo.c
Extension
.c
Size
4252 bytes
Lines
174
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (ctype == CACHE_TYPE_NOCACHE) {
			level--;
			break;
		}
		/* Separate instruction and data caches */
		leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1;
	}

	*level_p = level;
	*leaves_p = leaves;

	return 0;
}

int early_cache_level(unsigned int cpu)
{
	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);

	return detect_cache_level(&this_cpu_ci->num_levels, &this_cpu_ci->num_leaves);
}

int init_cache_level(unsigned int cpu)
{
	unsigned int level, leaves;
	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
	int fw_level;
	int ret;

	ret = detect_cache_level(&level, &leaves);
	if (ret)
		return ret;

	fw_level = of_find_last_cache_level(cpu);

	if (level < fw_level) {
		/*
		 * some external caches not specified in CLIDR_EL1
		 * the information may be available in the device tree
		 * only unified external caches are considered here
		 */
		leaves += (fw_level - level);
		level = fw_level;
	}

	this_cpu_ci->num_levels = level;
	this_cpu_ci->num_leaves = leaves;
	return 0;
}

int populate_cache_leaves(unsigned int cpu)
{
	unsigned int level, idx;
	enum cache_type type;
	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
	struct cacheinfo *this_leaf = this_cpu_ci->info_list;
	unsigned int arch = cpu_architecture();

	/* CLIDR is not present before ARMv7/v7m */
	if (arch < CPU_ARCH_ARMv7)
		return -EOPNOTSUPP;

	for (idx = 0, level = 1; level <= this_cpu_ci->num_levels &&
	     idx < this_cpu_ci->num_leaves; idx++, level++) {
		type = get_cache_type(level);
		if (type == CACHE_TYPE_SEPARATE) {
			ci_leaf_init(this_leaf++, CACHE_TYPE_DATA, level);
			ci_leaf_init(this_leaf++, CACHE_TYPE_INST, level);
		} else {
			ci_leaf_init(this_leaf++, type, level);
		}
	}

	return 0;
}

Annotation

Implementation Notes