arch/powerpc/kernel/setup_32.c

   1 /*
   2  * Common prep/pmac/chrp boot and setup code.
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/string.h>
   7 #include <linux/sched.h>
   8 #include <linux/init.h>
   9 #include <linux/kernel.h>
  10 #include <linux/reboot.h>
  11 #include <linux/delay.h>
  12 #include <linux/initrd.h>
  13 #include <linux/tty.h>
  14 #include <linux/seq_file.h>
  15 #include <linux/root_dev.h>
  16 #include <linux/cpu.h>
  17 #include <linux/console.h>
  18 #include <linux/memblock.h>
  19 #include <linux/export.h>
  20 #include <linux/nvram.h>
  21
  22 #include <asm/io.h>
  23 #include <asm/prom.h>
  24 #include <asm/processor.h>
  25 #include <asm/pgtable.h>
  26 #include <asm/setup.h>
  27 #include <asm/smp.h>
  28 #include <asm/elf.h>
  29 #include <asm/cputable.h>
  30 #include <asm/bootx.h>
  31 #include <asm/btext.h>
  32 #include <asm/machdep.h>
  33 #include <linux/uaccess.h>
  34 #include <asm/pmac_feature.h>
  35 #include <asm/sections.h>
  36 #include <asm/nvram.h>
  37 #include <asm/xmon.h>
  38 #include <asm/time.h>
  39 #include <asm/serial.h>
  40 #include <asm/udbg.h>
  41 #include <asm/code-patching.h>
  42 #include <asm/cpu_has_feature.h>
  43 #include <asm/asm-prototypes.h>
  44 #include <asm/kdump.h>
  45 #include <asm/feature-fixups.h>
  46
  47 #include "setup.h"
  48
  49 #define DBG(fmt...)
  50
  51 extern void bootx_init(unsigned long r4, unsigned long phys);
  52
  53 int boot_cpuid_phys;
  54 EXPORT_SYMBOL_GPL(boot_cpuid_phys);
  55
  56 int smp_hw_index[NR_CPUS];
  57 EXPORT_SYMBOL(smp_hw_index);
  58
  59 unsigned long ISA_DMA_THRESHOLD;
  60 unsigned int DMA_MODE_READ;
  61 unsigned int DMA_MODE_WRITE;
  62
  63 EXPORT_SYMBOL(DMA_MODE_READ);
  64 EXPORT_SYMBOL(DMA_MODE_WRITE);
  65
  66 /*
  67  * We're called here very early in the boot.
  68  *
  69  * Note that the kernel may be running at an address which is different
  70  * from the address that it was linked at, so we must use RELOC/PTRRELOC
  71  * to access static data (including strings).  -- paulus
  72  */
  73 notrace unsigned long __init early_init(unsigned long dt_ptr)
  74 {
  75         unsigned long offset = reloc_offset();
  76
  77         /* First zero the BSS -- use memset_io, some platforms don't have
  78          * caches on yet */
  79         memset_io((void __iomem *)PTRRELOC(&__bss_start), 0,
  80                         __bss_stop - __bss_start);
  81
  82         /*
  83          * Identify the CPU type and fix up code sections
  84          * that depend on which cpu we have.
  85          */
  86         identify_cpu(offset, mfspr(SPRN_PVR));
  87
  88         apply_feature_fixups();
  89
  90         return KERNELBASE + offset;
  91 }
  92
  93
  94 /*
  95  * This is run before start_kernel(), the kernel has been relocated
  96  * and we are running with enough of the MMU enabled to have our
  97  * proper kernel virtual addresses
  98  *
  99  * We do the initial parsing of the flat device-tree and prepares
 100  * for the MMU to be fully initialized.
 101  */
 102 notrace void __init machine_init(u64 dt_ptr)
 103 {
 104         unsigned int *addr = (unsigned int *)patch_site_addr(&patch__memset_nocache);
 105         unsigned long insn;
 106
 107         /* Configure static keys first, now that we're relocated. */
 108         setup_feature_keys();
 109
 110         /* Enable early debugging if any specified (see udbg.h) */
 111         udbg_early_init();
 112
 113         patch_instruction_site(&patch__memcpy_nocache, PPC_INST_NOP);
 114
 115         insn = create_cond_branch(addr, branch_target(addr), 0x820000);
 116         patch_instruction(addr, insn);  /* replace b by bne cr0 */
 117
 118         /* Do some early initialization based on the flat device tree */
 119         early_init_devtree(__va(dt_ptr));
 120
 121         early_init_mmu();
 122
 123         setup_kdump_trampoline();
 124 }
 125
 126 /* Checks "l2cr=xxxx" command-line option */
 127 static int __init ppc_setup_l2cr(char *str)
 128 {
 129         if (cpu_has_feature(CPU_FTR_L2CR)) {
 130                 unsigned long val = simple_strtoul(str, NULL, 0);
 131                 printk(KERN_INFO "l2cr set to %lx\n", val);
 132                 _set_L2CR(0);           /* force invalidate by disable cache */
 133                 _set_L2CR(val);         /* and enable it */
 134         }
 135         return 1;
 136 }
 137 __setup("l2cr=", ppc_setup_l2cr);
 138
 139 /* Checks "l3cr=xxxx" command-line option */
 140 static int __init ppc_setup_l3cr(char *str)
 141 {
 142         if (cpu_has_feature(CPU_FTR_L3CR)) {
 143                 unsigned long val = simple_strtoul(str, NULL, 0);
 144                 printk(KERN_INFO "l3cr set to %lx\n", val);
 145                 _set_L3CR(val);         /* and enable it */
 146         }
 147         return 1;
 148 }
 149 __setup("l3cr=", ppc_setup_l3cr);
 150
 151 static int __init ppc_init(void)
 152 {
 153         /* clear the progress line */
 154         if (ppc_md.progress)
 155                 ppc_md.progress("             ", 0xffff);
 156
 157         /* call platform init */
 158         if (ppc_md.init != NULL) {
 159                 ppc_md.init();
 160         }
 161         return 0;
 162 }
 163 arch_initcall(ppc_init);
 164
 165 static void *__init alloc_stack(void)
 166 {
 167         void *ptr = memblock_alloc(THREAD_SIZE, THREAD_SIZE);
 168
 169         if (!ptr)
 170                 panic("cannot allocate %d bytes for stack at %pS\n",
 171                       THREAD_SIZE, (void *)_RET_IP_);
 172
 173         return ptr;
 174 }
 175
 176 void __init irqstack_early_init(void)
 177 {
 178         unsigned int i;
 179
 180         /* interrupt stacks must be in lowmem, we get that for free on ppc32
 181          * as the memblock is limited to lowmem by default */
 182         for_each_possible_cpu(i) {
 183                 softirq_ctx[i] = alloc_stack();
 184                 hardirq_ctx[i] = alloc_stack();
 185         }
 186 }
 187
 188 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
 189 void __init exc_lvl_early_init(void)
 190 {
 191         unsigned int i, hw_cpu;
 192
 193         /* interrupt stacks must be in lowmem, we get that for free on ppc32
 194          * as the memblock is limited to lowmem by MEMBLOCK_REAL_LIMIT */
 195         for_each_possible_cpu(i) {
 196 #ifdef CONFIG_SMP
 197                 hw_cpu = get_hard_smp_processor_id(i);
 198 #else
 199                 hw_cpu = 0;
 200 #endif
 201
 202                 critirq_ctx[hw_cpu] = alloc_stack();
 203 #ifdef CONFIG_BOOKE
 204                 dbgirq_ctx[hw_cpu] = alloc_stack();
 205                 mcheckirq_ctx[hw_cpu] = alloc_stack();
 206 #endif
 207         }
 208 }
 209 #endif
 210
 211 void __init setup_power_save(void)
 212 {
 213 #ifdef CONFIG_PPC_BOOK3S_32
 214         if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
 215             cpu_has_feature(CPU_FTR_CAN_NAP))
 216                 ppc_md.power_save = ppc6xx_idle;
 217 #endif
 218
 219 #ifdef CONFIG_E500
 220         if (cpu_has_feature(CPU_FTR_CAN_DOZE) ||
 221             cpu_has_feature(CPU_FTR_CAN_NAP))
 222                 ppc_md.power_save = e500_idle;
 223 #endif
 224 }
 225
 226 __init void initialize_cache_info(void)
 227 {
 228         /*
 229          * Set cache line size based on type of cpu as a default.
 230          * Systems with OF can look in the properties on the cpu node(s)
 231          * for a possibly more accurate value.
 232          */
 233         dcache_bsize = cur_cpu_spec->dcache_bsize;
 234         icache_bsize = cur_cpu_spec->icache_bsize;
 235         ucache_bsize = 0;
 236         if (cpu_has_feature(CPU_FTR_UNIFIED_ID_CACHE))
 237                 ucache_bsize = icache_bsize = dcache_bsize;
 238 }