| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame^] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * arch/sh/kernel/cpu/sh3/probe.c |
| 4 | * |
| 5 | * CPU Subtype Probing for SH-3. |
| 6 | * |
| 7 | * Copyright (C) 1999, 2000 Niibe Yutaka |
| 8 | * Copyright (C) 2002 Paul Mundt |
| 9 | */ |
| 10 | |
| 11 | #include <linux/init.h> |
| 12 | #include <asm/processor.h> |
| 13 | #include <asm/cache.h> |
| 14 | #include <asm/io.h> |
| 15 | |
| 16 | void cpu_probe(void) |
| 17 | { |
| 18 | unsigned long addr0, addr1, data0, data1, data2, data3; |
| 19 | |
| 20 | jump_to_uncached(); |
| 21 | /* |
| 22 | * Check if the entry shadows or not. |
| 23 | * When shadowed, it's 128-entry system. |
| 24 | * Otherwise, it's 256-entry system. |
| 25 | */ |
| 26 | addr0 = CACHE_OC_ADDRESS_ARRAY + (3 << 12); |
| 27 | addr1 = CACHE_OC_ADDRESS_ARRAY + (1 << 12); |
| 28 | |
| 29 | /* First, write back & invalidate */ |
| 30 | data0 = __raw_readl(addr0); |
| 31 | __raw_writel(data0&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr0); |
| 32 | data1 = __raw_readl(addr1); |
| 33 | __raw_writel(data1&~(SH_CACHE_VALID|SH_CACHE_UPDATED), addr1); |
| 34 | |
| 35 | /* Next, check if there's shadow or not */ |
| 36 | data0 = __raw_readl(addr0); |
| 37 | data0 ^= SH_CACHE_VALID; |
| 38 | __raw_writel(data0, addr0); |
| 39 | data1 = __raw_readl(addr1); |
| 40 | data2 = data1 ^ SH_CACHE_VALID; |
| 41 | __raw_writel(data2, addr1); |
| 42 | data3 = __raw_readl(addr0); |
| 43 | |
| 44 | /* Lastly, invaliate them. */ |
| 45 | __raw_writel(data0&~SH_CACHE_VALID, addr0); |
| 46 | __raw_writel(data2&~SH_CACHE_VALID, addr1); |
| 47 | |
| 48 | back_to_cached(); |
| 49 | |
| 50 | boot_cpu_data.dcache.ways = 4; |
| 51 | boot_cpu_data.dcache.entry_shift = 4; |
| 52 | boot_cpu_data.dcache.linesz = L1_CACHE_BYTES; |
| 53 | boot_cpu_data.dcache.flags = 0; |
| 54 | |
| 55 | /* |
| 56 | * 7709A/7729 has 16K cache (256-entry), while 7702 has only |
| 57 | * 2K(direct) 7702 is not supported (yet) |
| 58 | */ |
| 59 | if (data0 == data1 && data2 == data3) { /* Shadow */ |
| 60 | boot_cpu_data.dcache.way_incr = (1 << 11); |
| 61 | boot_cpu_data.dcache.entry_mask = 0x7f0; |
| 62 | boot_cpu_data.dcache.sets = 128; |
| 63 | boot_cpu_data.type = CPU_SH7708; |
| 64 | |
| 65 | boot_cpu_data.flags |= CPU_HAS_MMU_PAGE_ASSOC; |
| 66 | } else { /* 7709A or 7729 */ |
| 67 | boot_cpu_data.dcache.way_incr = (1 << 12); |
| 68 | boot_cpu_data.dcache.entry_mask = 0xff0; |
| 69 | boot_cpu_data.dcache.sets = 256; |
| 70 | boot_cpu_data.type = CPU_SH7729; |
| 71 | |
| 72 | #if defined(CONFIG_CPU_SUBTYPE_SH7706) |
| 73 | boot_cpu_data.type = CPU_SH7706; |
| 74 | #endif |
| 75 | #if defined(CONFIG_CPU_SUBTYPE_SH7710) |
| 76 | boot_cpu_data.type = CPU_SH7710; |
| 77 | #endif |
| 78 | #if defined(CONFIG_CPU_SUBTYPE_SH7712) |
| 79 | boot_cpu_data.type = CPU_SH7712; |
| 80 | #endif |
| 81 | #if defined(CONFIG_CPU_SUBTYPE_SH7720) |
| 82 | boot_cpu_data.type = CPU_SH7720; |
| 83 | #endif |
| 84 | #if defined(CONFIG_CPU_SUBTYPE_SH7721) |
| 85 | boot_cpu_data.type = CPU_SH7721; |
| 86 | #endif |
| 87 | #if defined(CONFIG_CPU_SUBTYPE_SH7705) |
| 88 | boot_cpu_data.type = CPU_SH7705; |
| 89 | |
| 90 | #if defined(CONFIG_SH7705_CACHE_32KB) |
| 91 | boot_cpu_data.dcache.way_incr = (1 << 13); |
| 92 | boot_cpu_data.dcache.entry_mask = 0x1ff0; |
| 93 | boot_cpu_data.dcache.sets = 512; |
| 94 | __raw_writel(CCR_CACHE_32KB, CCR3_REG); |
| 95 | #else |
| 96 | __raw_writel(CCR_CACHE_16KB, CCR3_REG); |
| 97 | #endif |
| 98 | #endif |
| 99 | } |
| 100 | |
| 101 | /* |
| 102 | * SH-3 doesn't have separate caches |
| 103 | */ |
| 104 | boot_cpu_data.dcache.flags |= SH_CACHE_COMBINED; |
| 105 | boot_cpu_data.icache = boot_cpu_data.dcache; |
| 106 | |
| 107 | boot_cpu_data.family = CPU_FAMILY_SH3; |
| 108 | } |