Cache

发表于 分类于 阅读次数： 阅读次数： 本文字数： 1.1k 阅读时长 ≈ 1 分钟
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+----+  +----+   +----+  +----+
|CPU0|  |CPU1|   |CPU2|  |CPU3|
+----+  +----+   +----+  +----+
  +-+     +-+     +-+      +-+
    |     |         |      |
+---v-----v--+   +--v------v--+
|   L1 Cache |   |  L2 Cache  |
+------+-----+   +------+-----+
       |                |
+------v----------------v-----+
|         L2 Cache            |
+-----------------------------+

Cache 初始化

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kernel_start
	\->setup_arch
		\->cpu_cache_init
			\->r4k_cache_init
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#define cpu_dcache_size()           (32 * 1024)
#define cpu_dcache_ways()           8
#define cpu_dcache_line_size()      32
#define cpu_icache_size()           (32 * 1024)
#define cpu_icache_ways()           8
#define cpu_icache_line_size()      32

cpuinfo_mips

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struct cpuinfo_mips {
	unsigned int        udelay_val;
	...
	/*
	 *Capability and feature descriptor structure for MIPS CPU
	 */
	unsigned int        processor_id;
	unsigned int        fpu_id;
	unsigned int        msa_id;
	unsigned int        cputype;
	...
} __attribute__((aligned(SMP_CACHE_BYTES)));

extern struct cpuinfo_mips cpu_data[];
#define current_cpu_data cpu_data[smp_processor_id()]
#define raw_current_cpu_data cpu_data[raw_smp_processor_id()]

file: arch/mips/include/asm/cpu-info.h

  • 初始化：
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    struct cpuinfo_mips cpu_data[NR_CPUS] __read_mostly;
    EXPORT_SYMBOL(cpu_data);

    file: arch/mips/kernel/setup.c