1 // SPDX-License-Identifier: GPL-2.0
3 * arch/alpha/boot/main.c
5 * Copyright (C) 1994, 1995 Linus Torvalds
7 * This file is the bootloader for the Linux/AXP kernel
9 #include <linux/kernel.h>
10 #include <linux/slab.h>
11 #include <linux/string.h>
12 #include <generated/utsrelease.h>
15 #include <asm/console.h>
16 #include <asm/hwrpb.h>
18 #include <linux/stdarg.h>
22 extern unsigned long switch_to_osf_pal(unsigned long nr,
23 struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa,
25 struct hwrpb_struct *hwrpb = INIT_HWRPB;
26 static struct pcb_struct pcb_va[1];
29 * Find a physical address of a virtual object..
31 * This is easy using the virtual page table address.
35 find_pa(unsigned long *vptb, void *ptr)
37 unsigned long address = (unsigned long) ptr;
40 result = vptb[address >> 13];
43 result |= address & 0x1fff;
44 return (void *) result;
48 * This function moves into OSF/1 pal-code, and has a temporary
49 * PCB for that. The kernel proper should replace this PCB with
50 * the real one as soon as possible.
52 * The page table muckery in here depends on the fact that the boot
53 * code has the L1 page table identity-map itself in the second PTE
54 * in the L1 page table. Thus the L1-page is virtually addressable
55 * itself (through three levels) at virtual address 0x200802000.
58 #define VPTB ((unsigned long *) 0x200000000)
59 #define L1 ((unsigned long *) 0x200802000)
65 struct percpu_struct * percpu;
66 struct pcb_struct * pcb_pa;
68 /* Create the dummy PCB. */
71 pcb_va->ptbr = L1[1] >> 32;
78 pcb_pa = find_pa(VPTB, pcb_va);
82 * a1 = return address, but we give the asm the vaddr of the PCB
83 * a2 = physical addr of PCB
84 * a3 = new virtual page table pointer
85 * a4 = KSP (but the asm sets it)
87 srm_printk("Switching to OSF PAL-code .. ");
89 i = switch_to_osf_pal(2, pcb_va, pcb_pa, VPTB);
91 srm_printk("failed, code %ld\n", i);
95 percpu = (struct percpu_struct *)
96 (INIT_HWRPB->processor_offset + (unsigned long) INIT_HWRPB);
97 rev = percpu->pal_revision = percpu->palcode_avail[2];
99 srm_printk("Ok (rev %lx)\n", rev);
101 tbia(); /* do it directly in case we are SMP */
104 static inline long openboot(void)
109 result = callback_getenv(ENV_BOOTED_DEV, bootdev, 255);
112 return callback_open(bootdev, result & 255);
115 static inline long close(long dev)
117 return callback_close(dev);
120 static inline long load(long dev, unsigned long addr, unsigned long count)
124 long result, boot_size = &_end - (char *) BOOT_ADDR;
126 result = callback_getenv(ENV_BOOTED_FILE, bootfile, 255);
130 bootfile[result] = '\0';
132 srm_printk("Boot file specification (%s) not implemented\n",
134 return callback_read(dev, count, (void *)addr, boot_size/512 + 1);
140 static void runkernel(void)
142 __asm__ __volatile__(
146 : /* no outputs: it doesn't even return */
148 "r" (PAGE_SIZE + INIT_STACK));
151 void start_kernel(void)
158 srm_printk("Linux/AXP bootloader for Linux " UTS_RELEASE "\n");
159 if (INIT_HWRPB->pagesize != 8192) {
160 srm_printk("Expected 8kB pages, got %ldkB\n", INIT_HWRPB->pagesize >> 10);
166 srm_printk("Unable to open boot device: %016lx\n", dev);
170 srm_printk("Loading vmlinux ...");
171 i = load(dev, START_ADDR, KERNEL_SIZE);
173 if (i != KERNEL_SIZE) {
174 srm_printk("Failed (%lx)\n", i);
178 nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval));
182 envval[nbytes] = '\0';
183 strcpy((char*)ZERO_PGE, envval);
185 srm_printk(" Ok\nNow booting the kernel\n");
187 for (i = 0 ; i < 0x100000000 ; i++)