diff options
| author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
| commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
| tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/sh/kernel/cpu/init.c | |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/sh/kernel/cpu/init.c')
| -rw-r--r-- | arch/sh/kernel/cpu/init.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/arch/sh/kernel/cpu/init.c b/arch/sh/kernel/cpu/init.c new file mode 100644 index 000000000000..cf94e8ef17c5 --- /dev/null +++ b/arch/sh/kernel/cpu/init.c | |||
| @@ -0,0 +1,222 @@ | |||
| 1 | /* | ||
| 2 | * arch/sh/kernel/cpu/init.c | ||
| 3 | * | ||
| 4 | * CPU init code | ||
| 5 | * | ||
| 6 | * Copyright (C) 2002, 2003 Paul Mundt | ||
| 7 | * | ||
| 8 | * This file is subject to the terms and conditions of the GNU General Public | ||
| 9 | * License. See the file "COPYING" in the main directory of this archive | ||
| 10 | * for more details. | ||
| 11 | */ | ||
| 12 | #include <linux/init.h> | ||
| 13 | #include <linux/kernel.h> | ||
| 14 | #include <asm/processor.h> | ||
| 15 | #include <asm/uaccess.h> | ||
| 16 | #include <asm/system.h> | ||
| 17 | #include <asm/cacheflush.h> | ||
| 18 | #include <asm/cache.h> | ||
| 19 | #include <asm/io.h> | ||
| 20 | |||
| 21 | extern void detect_cpu_and_cache_system(void); | ||
| 22 | |||
| 23 | /* | ||
| 24 | * Generic wrapper for command line arguments to disable on-chip | ||
| 25 | * peripherals (nofpu, nodsp, and so forth). | ||
| 26 | */ | ||
| 27 | #define onchip_setup(x) \ | ||
| 28 | static int x##_disabled __initdata = 0; \ | ||
| 29 | \ | ||
| 30 | static int __init x##_setup(char *opts) \ | ||
| 31 | { \ | ||
| 32 | x##_disabled = 1; \ | ||
| 33 | return 0; \ | ||
| 34 | } \ | ||
| 35 | __setup("no" __stringify(x), x##_setup); | ||
| 36 | |||
| 37 | onchip_setup(fpu); | ||
| 38 | onchip_setup(dsp); | ||
| 39 | |||
| 40 | /* | ||
| 41 | * Generic first-level cache init | ||
| 42 | */ | ||
| 43 | static void __init cache_init(void) | ||
| 44 | { | ||
| 45 | unsigned long ccr, flags; | ||
| 46 | |||
| 47 | if (cpu_data->type == CPU_SH_NONE) | ||
| 48 | panic("Unknown CPU"); | ||
| 49 | |||
| 50 | jump_to_P2(); | ||
| 51 | ccr = ctrl_inl(CCR); | ||
| 52 | |||
| 53 | /* | ||
| 54 | * If the cache is already enabled .. flush it. | ||
| 55 | */ | ||
| 56 | if (ccr & CCR_CACHE_ENABLE) { | ||
| 57 | unsigned long ways, waysize, addrstart; | ||
| 58 | |||
| 59 | waysize = cpu_data->dcache.sets; | ||
| 60 | |||
| 61 | /* | ||
| 62 | * If the OC is already in RAM mode, we only have | ||
| 63 | * half of the entries to flush.. | ||
| 64 | */ | ||
| 65 | if (ccr & CCR_CACHE_ORA) | ||
| 66 | waysize >>= 1; | ||
| 67 | |||
| 68 | waysize <<= cpu_data->dcache.entry_shift; | ||
| 69 | |||
| 70 | #ifdef CCR_CACHE_EMODE | ||
| 71 | /* If EMODE is not set, we only have 1 way to flush. */ | ||
| 72 | if (!(ccr & CCR_CACHE_EMODE)) | ||
| 73 | ways = 1; | ||
| 74 | else | ||
| 75 | #endif | ||
| 76 | ways = cpu_data->dcache.ways; | ||
| 77 | |||
| 78 | addrstart = CACHE_OC_ADDRESS_ARRAY; | ||
| 79 | do { | ||
| 80 | unsigned long addr; | ||
| 81 | |||
| 82 | for (addr = addrstart; | ||
| 83 | addr < addrstart + waysize; | ||
| 84 | addr += cpu_data->dcache.linesz) | ||
| 85 | ctrl_outl(0, addr); | ||
| 86 | |||
| 87 | addrstart += cpu_data->dcache.way_incr; | ||
| 88 | } while (--ways); | ||
| 89 | } | ||
| 90 | |||
| 91 | /* | ||
| 92 | * Default CCR values .. enable the caches | ||
| 93 | * and invalidate them immediately.. | ||
| 94 | */ | ||
| 95 | flags = CCR_CACHE_ENABLE | CCR_CACHE_INVALIDATE; | ||
| 96 | |||
| 97 | #ifdef CCR_CACHE_EMODE | ||
| 98 | /* Force EMODE if possible */ | ||
| 99 | if (cpu_data->dcache.ways > 1) | ||
| 100 | flags |= CCR_CACHE_EMODE; | ||
| 101 | #endif | ||
| 102 | |||
| 103 | #ifdef CONFIG_SH_WRITETHROUGH | ||
| 104 | /* Turn on Write-through caching */ | ||
| 105 | flags |= CCR_CACHE_WT; | ||
| 106 | #else | ||
| 107 | /* .. or default to Write-back */ | ||
| 108 | flags |= CCR_CACHE_CB; | ||
| 109 | #endif | ||
| 110 | |||
| 111 | #ifdef CONFIG_SH_OCRAM | ||
| 112 | /* Turn on OCRAM -- halve the OC */ | ||
| 113 | flags |= CCR_CACHE_ORA; | ||
| 114 | cpu_data->dcache.sets >>= 1; | ||
| 115 | #endif | ||
| 116 | |||
| 117 | ctrl_outl(flags, CCR); | ||
| 118 | back_to_P1(); | ||
| 119 | } | ||
| 120 | |||
| 121 | #ifdef CONFIG_SH_DSP | ||
| 122 | static void __init release_dsp(void) | ||
| 123 | { | ||
| 124 | unsigned long sr; | ||
| 125 | |||
| 126 | /* Clear SR.DSP bit */ | ||
| 127 | __asm__ __volatile__ ( | ||
| 128 | "stc\tsr, %0\n\t" | ||
| 129 | "and\t%1, %0\n\t" | ||
| 130 | "ldc\t%0, sr\n\t" | ||
| 131 | : "=&r" (sr) | ||
| 132 | : "r" (~SR_DSP) | ||
| 133 | ); | ||
| 134 | } | ||
| 135 | |||
| 136 | static void __init dsp_init(void) | ||
| 137 | { | ||
| 138 | unsigned long sr; | ||
| 139 | |||
| 140 | /* | ||
| 141 | * Set the SR.DSP bit, wait for one instruction, and then read | ||
| 142 | * back the SR value. | ||
| 143 | */ | ||
| 144 | __asm__ __volatile__ ( | ||
| 145 | "stc\tsr, %0\n\t" | ||
| 146 | "or\t%1, %0\n\t" | ||
| 147 | "ldc\t%0, sr\n\t" | ||
| 148 | "nop\n\t" | ||
| 149 | "stc\tsr, %0\n\t" | ||
| 150 | : "=&r" (sr) | ||
| 151 | : "r" (SR_DSP) | ||
| 152 | ); | ||
| 153 | |||
| 154 | /* If the DSP bit is still set, this CPU has a DSP */ | ||
| 155 | if (sr & SR_DSP) | ||
| 156 | cpu_data->flags |= CPU_HAS_DSP; | ||
| 157 | |||
| 158 | /* Now that we've determined the DSP status, clear the DSP bit. */ | ||
| 159 | release_dsp(); | ||
| 160 | } | ||
| 161 | #endif /* CONFIG_SH_DSP */ | ||
| 162 | |||
| 163 | /** | ||
| 164 | * sh_cpu_init | ||
| 165 | * | ||
| 166 | * This is our initial entry point for each CPU, and is invoked on the boot | ||
| 167 | * CPU prior to calling start_kernel(). For SMP, a combination of this and | ||
| 168 | * start_secondary() will bring up each processor to a ready state prior | ||
| 169 | * to hand forking the idle loop. | ||
| 170 | * | ||
| 171 | * We do all of the basic processor init here, including setting up the | ||
| 172 | * caches, FPU, DSP, kicking the UBC, etc. By the time start_kernel() is | ||
| 173 | * hit (and subsequently platform_setup()) things like determining the | ||
| 174 | * CPU subtype and initial configuration will all be done. | ||
| 175 | * | ||
| 176 | * Each processor family is still responsible for doing its own probing | ||
| 177 | * and cache configuration in detect_cpu_and_cache_system(). | ||
| 178 | */ | ||
| 179 | asmlinkage void __init sh_cpu_init(void) | ||
| 180 | { | ||
| 181 | /* First, probe the CPU */ | ||
| 182 | detect_cpu_and_cache_system(); | ||
| 183 | |||
| 184 | /* Init the cache */ | ||
| 185 | cache_init(); | ||
| 186 | |||
| 187 | /* Disable the FPU */ | ||
| 188 | if (fpu_disabled) { | ||
| 189 | printk("FPU Disabled\n"); | ||
| 190 | cpu_data->flags &= ~CPU_HAS_FPU; | ||
| 191 | disable_fpu(); | ||
| 192 | } | ||
| 193 | |||
| 194 | /* FPU initialization */ | ||
| 195 | if ((cpu_data->flags & CPU_HAS_FPU)) { | ||
| 196 | clear_thread_flag(TIF_USEDFPU); | ||
| 197 | clear_used_math(); | ||
| 198 | } | ||
| 199 | |||
| 200 | #ifdef CONFIG_SH_DSP | ||
| 201 | /* Probe for DSP */ | ||
| 202 | dsp_init(); | ||
| 203 | |||
| 204 | /* Disable the DSP */ | ||
| 205 | if (dsp_disabled) { | ||
| 206 | printk("DSP Disabled\n"); | ||
| 207 | cpu_data->flags &= ~CPU_HAS_DSP; | ||
| 208 | release_dsp(); | ||
| 209 | } | ||
| 210 | #endif | ||
| 211 | |||
| 212 | #ifdef CONFIG_UBC_WAKEUP | ||
| 213 | /* | ||
| 214 | * Some brain-damaged loaders decided it would be a good idea to put | ||
| 215 | * the UBC to sleep. This causes some issues when it comes to things | ||
| 216 | * like PTRACE_SINGLESTEP or doing hardware watchpoints in GDB. So .. | ||
| 217 | * we wake it up and hope that all is well. | ||
| 218 | */ | ||
| 219 | ubc_wakeup(); | ||
| 220 | #endif | ||
| 221 | } | ||
| 222 | |||
