Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * arch/alpha/boot/main.c |
| 3 | * |
| 4 | * Copyright (C) 1994, 1995 Linus Torvalds |
| 5 | * |
| 6 | * This file is the bootloader for the Linux/AXP kernel |
| 7 | */ |
| 8 | #include <linux/kernel.h> |
| 9 | #include <linux/string.h> |
Sam Ravnborg | 63104ee | 2006-07-03 23:30:54 +0200 | [diff] [blame] | 10 | #include <linux/utsrelease.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | #include <linux/mm.h> |
| 12 | |
| 13 | #include <asm/system.h> |
| 14 | #include <asm/console.h> |
| 15 | #include <asm/hwrpb.h> |
| 16 | #include <asm/pgtable.h> |
| 17 | |
| 18 | #include <stdarg.h> |
| 19 | |
| 20 | #include "ksize.h" |
| 21 | |
| 22 | extern int vsprintf(char *, const char *, va_list); |
| 23 | extern unsigned long switch_to_osf_pal(unsigned long nr, |
| 24 | struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa, |
| 25 | unsigned long *vptb); |
| 26 | struct hwrpb_struct *hwrpb = INIT_HWRPB; |
| 27 | static struct pcb_struct pcb_va[1]; |
| 28 | |
| 29 | /* |
| 30 | * Find a physical address of a virtual object.. |
| 31 | * |
| 32 | * This is easy using the virtual page table address. |
| 33 | */ |
| 34 | |
| 35 | static inline void * |
| 36 | find_pa(unsigned long *vptb, void *ptr) |
| 37 | { |
| 38 | unsigned long address = (unsigned long) ptr; |
| 39 | unsigned long result; |
| 40 | |
| 41 | result = vptb[address >> 13]; |
| 42 | result >>= 32; |
| 43 | result <<= 13; |
| 44 | result |= address & 0x1fff; |
| 45 | return (void *) result; |
| 46 | } |
| 47 | |
| 48 | /* |
| 49 | * This function moves into OSF/1 pal-code, and has a temporary |
| 50 | * PCB for that. The kernel proper should replace this PCB with |
| 51 | * the real one as soon as possible. |
| 52 | * |
| 53 | * The page table muckery in here depends on the fact that the boot |
| 54 | * code has the L1 page table identity-map itself in the second PTE |
| 55 | * in the L1 page table. Thus the L1-page is virtually addressable |
| 56 | * itself (through three levels) at virtual address 0x200802000. |
| 57 | */ |
| 58 | |
| 59 | #define VPTB ((unsigned long *) 0x200000000) |
| 60 | #define L1 ((unsigned long *) 0x200802000) |
| 61 | |
| 62 | void |
| 63 | pal_init(void) |
| 64 | { |
| 65 | unsigned long i, rev; |
| 66 | struct percpu_struct * percpu; |
| 67 | struct pcb_struct * pcb_pa; |
| 68 | |
| 69 | /* Create the dummy PCB. */ |
| 70 | pcb_va->ksp = 0; |
| 71 | pcb_va->usp = 0; |
| 72 | pcb_va->ptbr = L1[1] >> 32; |
| 73 | pcb_va->asn = 0; |
| 74 | pcb_va->pcc = 0; |
| 75 | pcb_va->unique = 0; |
| 76 | pcb_va->flags = 1; |
| 77 | pcb_va->res1 = 0; |
| 78 | pcb_va->res2 = 0; |
| 79 | pcb_pa = find_pa(VPTB, pcb_va); |
| 80 | |
| 81 | /* |
| 82 | * a0 = 2 (OSF) |
| 83 | * a1 = return address, but we give the asm the vaddr of the PCB |
| 84 | * a2 = physical addr of PCB |
| 85 | * a3 = new virtual page table pointer |
| 86 | * a4 = KSP (but the asm sets it) |
| 87 | */ |
| 88 | srm_printk("Switching to OSF PAL-code .. "); |
| 89 | |
| 90 | i = switch_to_osf_pal(2, pcb_va, pcb_pa, VPTB); |
| 91 | if (i) { |
| 92 | srm_printk("failed, code %ld\n", i); |
| 93 | __halt(); |
| 94 | } |
| 95 | |
| 96 | percpu = (struct percpu_struct *) |
| 97 | (INIT_HWRPB->processor_offset + (unsigned long) INIT_HWRPB); |
| 98 | rev = percpu->pal_revision = percpu->palcode_avail[2]; |
| 99 | |
| 100 | srm_printk("Ok (rev %lx)\n", rev); |
| 101 | |
| 102 | tbia(); /* do it directly in case we are SMP */ |
| 103 | } |
| 104 | |
| 105 | static inline long openboot(void) |
| 106 | { |
| 107 | char bootdev[256]; |
| 108 | long result; |
| 109 | |
| 110 | result = callback_getenv(ENV_BOOTED_DEV, bootdev, 255); |
| 111 | if (result < 0) |
| 112 | return result; |
| 113 | return callback_open(bootdev, result & 255); |
| 114 | } |
| 115 | |
| 116 | static inline long close(long dev) |
| 117 | { |
| 118 | return callback_close(dev); |
| 119 | } |
| 120 | |
| 121 | static inline long load(long dev, unsigned long addr, unsigned long count) |
| 122 | { |
| 123 | char bootfile[256]; |
| 124 | extern char _end; |
| 125 | long result, boot_size = &_end - (char *) BOOT_ADDR; |
| 126 | |
| 127 | result = callback_getenv(ENV_BOOTED_FILE, bootfile, 255); |
| 128 | if (result < 0) |
| 129 | return result; |
| 130 | result &= 255; |
| 131 | bootfile[result] = '\0'; |
| 132 | if (result) |
| 133 | srm_printk("Boot file specification (%s) not implemented\n", |
| 134 | bootfile); |
Meelis Roos | 9965a5d | 2007-07-31 00:38:13 -0700 | [diff] [blame] | 135 | return callback_read(dev, count, (void *)addr, boot_size/512 + 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | } |
| 137 | |
| 138 | /* |
| 139 | * Start the kernel. |
| 140 | */ |
| 141 | static void runkernel(void) |
| 142 | { |
| 143 | __asm__ __volatile__( |
| 144 | "bis %1,%1,$30\n\t" |
| 145 | "bis %0,%0,$26\n\t" |
| 146 | "ret ($26)" |
| 147 | : /* no outputs: it doesn't even return */ |
| 148 | : "r" (START_ADDR), |
| 149 | "r" (PAGE_SIZE + INIT_STACK)); |
| 150 | } |
| 151 | |
| 152 | void start_kernel(void) |
| 153 | { |
| 154 | long i; |
| 155 | long dev; |
| 156 | int nbytes; |
| 157 | char envval[256]; |
| 158 | |
| 159 | srm_printk("Linux/AXP bootloader for Linux " UTS_RELEASE "\n"); |
| 160 | if (INIT_HWRPB->pagesize != 8192) { |
| 161 | srm_printk("Expected 8kB pages, got %ldkB\n", INIT_HWRPB->pagesize >> 10); |
| 162 | return; |
| 163 | } |
| 164 | pal_init(); |
| 165 | dev = openboot(); |
| 166 | if (dev < 0) { |
| 167 | srm_printk("Unable to open boot device: %016lx\n", dev); |
| 168 | return; |
| 169 | } |
| 170 | dev &= 0xffffffff; |
| 171 | srm_printk("Loading vmlinux ..."); |
| 172 | i = load(dev, START_ADDR, KERNEL_SIZE); |
| 173 | close(dev); |
| 174 | if (i != KERNEL_SIZE) { |
| 175 | srm_printk("Failed (%lx)\n", i); |
| 176 | return; |
| 177 | } |
| 178 | |
| 179 | nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval)); |
| 180 | if (nbytes < 0) { |
| 181 | nbytes = 0; |
| 182 | } |
| 183 | envval[nbytes] = '\0'; |
| 184 | strcpy((char*)ZERO_PGE, envval); |
| 185 | |
| 186 | srm_printk(" Ok\nNow booting the kernel\n"); |
| 187 | runkernel(); |
| 188 | for (i = 0 ; i < 0x100000000 ; i++) |
| 189 | /* nothing */; |
| 190 | __halt(); |
| 191 | } |