/* * arch/alpha/boot/main.c * * Copyright (C) 1994, 1995 Linus Torvalds * * This file is the bootloader for the Linux/AXP kernel */ #include <linux/kernel.h> #include <linux/string.h> #include <linux/version.h> #include <linux/mm.h> #include <asm/system.h> #include <asm/console.h> #include <asm/hwrpb.h> #include <asm/pgtable.h> #include <stdarg.h> #include "ksize.h" extern int vsprintf(char *, const char *, va_list); extern unsigned long switch_to_osf_pal(unsigned long nr, struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa, unsigned long *vptb); struct hwrpb_struct *hwrpb = INIT_HWRPB; static struct pcb_struct pcb_va[1]; /* * Find a physical address of a virtual object.. * * This is easy using the virtual page table address. */ static inline void * find_pa(unsigned long *vptb, void *ptr) { unsigned long address = (unsigned long) ptr; unsigned long result; result = vptb[address >> 13]; result >>= 32; result <<= 13; result |= address & 0x1fff; return (void *) result; } /* * This function moves into OSF/1 pal-code, and has a temporary * PCB for that. The kernel proper should replace this PCB with * the real one as soon as possible. * * The page table muckery in here depends on the fact that the boot * code has the L1 page table identity-map itself in the second PTE * in the L1 page table. Thus the L1-page is virtually addressable * itself (through three levels) at virtual address 0x200802000. */ #define VPTB ((unsigned long *) 0x200000000) #define L1 ((unsigned long *) 0x200802000) void pal_init(void) { unsigned long i, rev; struct percpu_struct * percpu; struct pcb_struct * pcb_pa; /* Create the dummy PCB. */ pcb_va->ksp = 0; pcb_va->usp = 0; pcb_va->ptbr = L1[1] >> 32; pcb_va->asn = 0; pcb_va->pcc = 0; pcb_va->unique = 0; pcb_va->flags = 1; pcb_va->res1 = 0; pcb_va->res2 = 0; pcb_pa = find_pa(VPTB, pcb_va); /* * a0 = 2 (OSF) * a1 = return address, but we give the asm the vaddr of the PCB * a2 = physical addr of PCB * a3 = new virtual page table pointer * a4 = KSP (but the asm sets it) */ srm_printk("Switching to OSF PAL-code .. "); i = switch_to_osf_pal(2, pcb_va, pcb_pa, VPTB); if (i) { srm_printk("failed, code %ld\n", i); __halt(); } percpu = (struct percpu_struct *) (INIT_HWRPB->processor_offset + (unsigned long) INIT_HWRPB); rev = percpu->pal_revision = percpu->palcode_avail[2]; srm_printk("Ok (rev %lx)\n", rev); tbia(); /* do it directly in case we are SMP */ } static inline long openboot(void) { char bootdev[256]; long result; result = callback_getenv(ENV_BOOTED_DEV, bootdev, 255); if (result < 0) return result; return callback_open(bootdev, result & 255); } static inline long close(long dev) { return callback_close(dev); } static inline long load(long dev, unsigned long addr, unsigned long count) { char bootfile[256]; extern char _end; long result, boot_size = &_end - (char *) BOOT_ADDR; result = callback_getenv(ENV_BOOTED_FILE, bootfile, 255); if (result < 0) return result; result &= 255; bootfile[result] = '\0'; if (result) srm_printk("Boot file specification (%s) not implemented\n", bootfile); return callback_read(dev, count, addr, boot_size/512 + 1); } /* * Start the kernel. */ static void runkernel(void) { __asm__ __volatile__( "bis %1,%1,$30\n\t" "bis %0,%0,$26\n\t" "ret ($26)" : /* no outputs: it doesn't even return */ : "r" (START_ADDR), "r" (PAGE_SIZE + INIT_STACK)); } void start_kernel(void) { long i; long dev; int nbytes; char envval[256]; srm_printk("Linux/AXP bootloader for Linux " UTS_RELEASE "\n"); if (INIT_HWRPB->pagesize != 8192) { srm_printk("Expected 8kB pages, got %ldkB\n", INIT_HWRPB->pagesize >> 10); return; } pal_init(); dev = openboot(); if (dev < 0) { srm_printk("Unable to open boot device: %016lx\n", dev); return; } dev &= 0xffffffff; srm_printk("Loading vmlinux ..."); i = load(dev, START_ADDR, KERNEL_SIZE); close(dev); if (i != KERNEL_SIZE) { srm_printk("Failed (%lx)\n", i); return; } nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval)); if (nbytes < 0) { nbytes = 0; } envval[nbytes] = '\0'; strcpy((char*)ZERO_PGE, envval); srm_printk(" Ok\nNow booting the kernel\n"); runkernel(); for (i = 0 ; i < 0x100000000 ; i++) /* nothing */; __halt(); }