1 /* 2 * arch/sh/kernel/cpu/sh3/probe.c 3 * 4 * CPU Subtype Probing for SH-3. 5 * 6 * Copyright (C) 1999, 2000 Niibe Yutaka 7 * Copyright (C) 2002 Paul Mundt 8 * 9 * This file is subject to the terms and conditions of the GNU General Public 10 * License. See the file "COPYING" in the main directory of this archive 11 * for more details. 12 */ 13 14 #include <linux/init.h> 15 #include <asm/processor.h> 16 #include <asm/cache.h> 17 #include <asm/io.h> 18 19 int __uses_jump_to_uncached detect_cpu_and_cache_system(void) 20 { 21 unsigned long addr0, addr1, data0, data1, data2, data3; 22 23 jump_to_uncached(); 24 /* 25 * Check if the entry shadows or not. 26 * When shadowed, it's 128-entry system. 27 * Otherwise, it's 256-entry system. 28 */ 29 addr0 = CACHE_OC_ADDRESS_ARRAY + (3 << 12); 30 addr1 = CACHE_OC_ADDRESS_ARRAY + (1 << 12); 31 32 /* First, write back & invalidate */ 33 data0 = ctrl_inl(addr0); 34 ctrl_outl(data0&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr0); 35 data1 = ctrl_inl(addr1); 36 ctrl_outl(data1&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr1); 37 38 /* Next, check if there's shadow or not */ 39 data0 = ctrl_inl(addr0); 40 data0 ^= SH_CACHE_VALID; 41 ctrl_outl(data0, addr0); 42 data1 = ctrl_inl(addr1); 43 data2 = data1 ^ SH_CACHE_VALID; 44 ctrl_outl(data2, addr1); 45 data3 = ctrl_inl(addr0); 46 47 /* Lastly, invaliate them. */ 48 ctrl_outl(data0&~SH_CACHE_VALID, addr0); 49 ctrl_outl(data2&~SH_CACHE_VALID, addr1); 50 51 back_to_cached(); 52 53 boot_cpu_data.dcache.ways = 4; 54 boot_cpu_data.dcache.entry_shift = 4; 55 boot_cpu_data.dcache.linesz = L1_CACHE_BYTES; 56 boot_cpu_data.dcache.flags = 0; 57 58 /* 59 * 7709A/7729 has 16K cache (256-entry), while 7702 has only 60 * 2K(direct) 7702 is not supported (yet) 61 */ 62 if (data0 == data1 && data2 == data3) { /* Shadow */ 63 boot_cpu_data.dcache.way_incr = (1 << 11); 64 boot_cpu_data.dcache.entry_mask = 0x7f0; 65 boot_cpu_data.dcache.sets = 128; 66 boot_cpu_data.type = CPU_SH7708; 67 68 boot_cpu_data.flags |= CPU_HAS_MMU_PAGE_ASSOC; 69 } else { /* 7709A or 7729 */ 70 boot_cpu_data.dcache.way_incr = (1 << 12); 71 boot_cpu_data.dcache.entry_mask = 0xff0; 72 boot_cpu_data.dcache.sets = 256; 73 boot_cpu_data.type = CPU_SH7729; 74 75 #if defined(CONFIG_CPU_SUBTYPE_SH7706) 76 boot_cpu_data.type = CPU_SH7706; 77 #endif 78 #if defined(CONFIG_CPU_SUBTYPE_SH7710) 79 boot_cpu_data.type = CPU_SH7710; 80 #endif 81 #if defined(CONFIG_CPU_SUBTYPE_SH7712) 82 boot_cpu_data.type = CPU_SH7712; 83 #endif 84 #if defined(CONFIG_CPU_SUBTYPE_SH7720) 85 boot_cpu_data.type = CPU_SH7720; 86 #endif 87 #if defined(CONFIG_CPU_SUBTYPE_SH7721) 88 boot_cpu_data.type = CPU_SH7721; 89 #endif 90 #if defined(CONFIG_CPU_SUBTYPE_SH7705) 91 boot_cpu_data.type = CPU_SH7705; 92 93 #if defined(CONFIG_SH7705_CACHE_32KB) 94 boot_cpu_data.dcache.way_incr = (1 << 13); 95 boot_cpu_data.dcache.entry_mask = 0x1ff0; 96 boot_cpu_data.dcache.sets = 512; 97 ctrl_outl(CCR_CACHE_32KB, CCR3_REG); 98 #else 99 ctrl_outl(CCR_CACHE_16KB, CCR3_REG); 100 #endif 101 #endif 102 } 103 104 /* 105 * SH-3 doesn't have separate caches 106 */ 107 boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED; 108 boot_cpu_data.icache = boot_cpu_data.dcache; 109 110 boot_cpu_data.family = CPU_FAMILY_SH3; 111 112 return 0; 113 } 114