1b2441318SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0
21da177e4SLinus Torvalds /*
31da177e4SLinus Torvalds * arch/alpha/boot/main.c
41da177e4SLinus Torvalds *
51da177e4SLinus Torvalds * Copyright (C) 1994, 1995 Linus Torvalds
61da177e4SLinus Torvalds *
71da177e4SLinus Torvalds * This file is the bootloader for the Linux/AXP kernel
81da177e4SLinus Torvalds */
91da177e4SLinus Torvalds #include <linux/kernel.h>
105a0e3ad6STejun Heo #include <linux/slab.h>
111da177e4SLinus Torvalds #include <linux/string.h>
12273b281fSSam Ravnborg #include <generated/utsrelease.h>
131da177e4SLinus Torvalds #include <linux/mm.h>
141da177e4SLinus Torvalds
151da177e4SLinus Torvalds #include <asm/console.h>
161da177e4SLinus Torvalds #include <asm/hwrpb.h>
171da177e4SLinus Torvalds
18*e07f68d5SAl Viro #include <linux/stdarg.h>
191da177e4SLinus Torvalds
201da177e4SLinus Torvalds #include "ksize.h"
211da177e4SLinus Torvalds
221da177e4SLinus Torvalds extern unsigned long switch_to_osf_pal(unsigned long nr,
231da177e4SLinus Torvalds struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa,
241da177e4SLinus Torvalds unsigned long *vptb);
251da177e4SLinus Torvalds struct hwrpb_struct *hwrpb = INIT_HWRPB;
261da177e4SLinus Torvalds static struct pcb_struct pcb_va[1];
271da177e4SLinus Torvalds
281da177e4SLinus Torvalds /*
291da177e4SLinus Torvalds * Find a physical address of a virtual object..
301da177e4SLinus Torvalds *
311da177e4SLinus Torvalds * This is easy using the virtual page table address.
321da177e4SLinus Torvalds */
331da177e4SLinus Torvalds
341da177e4SLinus Torvalds static inline void *
find_pa(unsigned long * vptb,void * ptr)351da177e4SLinus Torvalds find_pa(unsigned long *vptb, void *ptr)
361da177e4SLinus Torvalds {
371da177e4SLinus Torvalds unsigned long address = (unsigned long) ptr;
381da177e4SLinus Torvalds unsigned long result;
391da177e4SLinus Torvalds
401da177e4SLinus Torvalds result = vptb[address >> 13];
411da177e4SLinus Torvalds result >>= 32;
421da177e4SLinus Torvalds result <<= 13;
431da177e4SLinus Torvalds result |= address & 0x1fff;
441da177e4SLinus Torvalds return (void *) result;
451da177e4SLinus Torvalds }
461da177e4SLinus Torvalds
471da177e4SLinus Torvalds /*
481da177e4SLinus Torvalds * This function moves into OSF/1 pal-code, and has a temporary
491da177e4SLinus Torvalds * PCB for that. The kernel proper should replace this PCB with
501da177e4SLinus Torvalds * the real one as soon as possible.
511da177e4SLinus Torvalds *
521da177e4SLinus Torvalds * The page table muckery in here depends on the fact that the boot
531da177e4SLinus Torvalds * code has the L1 page table identity-map itself in the second PTE
541da177e4SLinus Torvalds * in the L1 page table. Thus the L1-page is virtually addressable
551da177e4SLinus Torvalds * itself (through three levels) at virtual address 0x200802000.
561da177e4SLinus Torvalds */
571da177e4SLinus Torvalds
581da177e4SLinus Torvalds #define VPTB ((unsigned long *) 0x200000000)
591da177e4SLinus Torvalds #define L1 ((unsigned long *) 0x200802000)
601da177e4SLinus Torvalds
611da177e4SLinus Torvalds void
pal_init(void)621da177e4SLinus Torvalds pal_init(void)
631da177e4SLinus Torvalds {
641da177e4SLinus Torvalds unsigned long i, rev;
651da177e4SLinus Torvalds struct percpu_struct * percpu;
661da177e4SLinus Torvalds struct pcb_struct * pcb_pa;
671da177e4SLinus Torvalds
681da177e4SLinus Torvalds /* Create the dummy PCB. */
691da177e4SLinus Torvalds pcb_va->ksp = 0;
701da177e4SLinus Torvalds pcb_va->usp = 0;
711da177e4SLinus Torvalds pcb_va->ptbr = L1[1] >> 32;
721da177e4SLinus Torvalds pcb_va->asn = 0;
731da177e4SLinus Torvalds pcb_va->pcc = 0;
741da177e4SLinus Torvalds pcb_va->unique = 0;
751da177e4SLinus Torvalds pcb_va->flags = 1;
761da177e4SLinus Torvalds pcb_va->res1 = 0;
771da177e4SLinus Torvalds pcb_va->res2 = 0;
781da177e4SLinus Torvalds pcb_pa = find_pa(VPTB, pcb_va);
791da177e4SLinus Torvalds
801da177e4SLinus Torvalds /*
811da177e4SLinus Torvalds * a0 = 2 (OSF)
821da177e4SLinus Torvalds * a1 = return address, but we give the asm the vaddr of the PCB
831da177e4SLinus Torvalds * a2 = physical addr of PCB
841da177e4SLinus Torvalds * a3 = new virtual page table pointer
851da177e4SLinus Torvalds * a4 = KSP (but the asm sets it)
861da177e4SLinus Torvalds */
871da177e4SLinus Torvalds srm_printk("Switching to OSF PAL-code .. ");
881da177e4SLinus Torvalds
891da177e4SLinus Torvalds i = switch_to_osf_pal(2, pcb_va, pcb_pa, VPTB);
901da177e4SLinus Torvalds if (i) {
911da177e4SLinus Torvalds srm_printk("failed, code %ld\n", i);
921da177e4SLinus Torvalds __halt();
931da177e4SLinus Torvalds }
941da177e4SLinus Torvalds
951da177e4SLinus Torvalds percpu = (struct percpu_struct *)
961da177e4SLinus Torvalds (INIT_HWRPB->processor_offset + (unsigned long) INIT_HWRPB);
971da177e4SLinus Torvalds rev = percpu->pal_revision = percpu->palcode_avail[2];
981da177e4SLinus Torvalds
991da177e4SLinus Torvalds srm_printk("Ok (rev %lx)\n", rev);
1001da177e4SLinus Torvalds
1011da177e4SLinus Torvalds tbia(); /* do it directly in case we are SMP */
1021da177e4SLinus Torvalds }
1031da177e4SLinus Torvalds
openboot(void)1041da177e4SLinus Torvalds static inline long openboot(void)
1051da177e4SLinus Torvalds {
1061da177e4SLinus Torvalds char bootdev[256];
1071da177e4SLinus Torvalds long result;
1081da177e4SLinus Torvalds
1091da177e4SLinus Torvalds result = callback_getenv(ENV_BOOTED_DEV, bootdev, 255);
1101da177e4SLinus Torvalds if (result < 0)
1111da177e4SLinus Torvalds return result;
1121da177e4SLinus Torvalds return callback_open(bootdev, result & 255);
1131da177e4SLinus Torvalds }
1141da177e4SLinus Torvalds
close(long dev)1151da177e4SLinus Torvalds static inline long close(long dev)
1161da177e4SLinus Torvalds {
1171da177e4SLinus Torvalds return callback_close(dev);
1181da177e4SLinus Torvalds }
1191da177e4SLinus Torvalds
load(long dev,unsigned long addr,unsigned long count)1201da177e4SLinus Torvalds static inline long load(long dev, unsigned long addr, unsigned long count)
1211da177e4SLinus Torvalds {
1221da177e4SLinus Torvalds char bootfile[256];
1231da177e4SLinus Torvalds extern char _end;
1241da177e4SLinus Torvalds long result, boot_size = &_end - (char *) BOOT_ADDR;
1251da177e4SLinus Torvalds
1261da177e4SLinus Torvalds result = callback_getenv(ENV_BOOTED_FILE, bootfile, 255);
1271da177e4SLinus Torvalds if (result < 0)
1281da177e4SLinus Torvalds return result;
1291da177e4SLinus Torvalds result &= 255;
1301da177e4SLinus Torvalds bootfile[result] = '\0';
1311da177e4SLinus Torvalds if (result)
1321da177e4SLinus Torvalds srm_printk("Boot file specification (%s) not implemented\n",
1331da177e4SLinus Torvalds bootfile);
1349965a5d5SMeelis Roos return callback_read(dev, count, (void *)addr, boot_size/512 + 1);
1351da177e4SLinus Torvalds }
1361da177e4SLinus Torvalds
1371da177e4SLinus Torvalds /*
1381da177e4SLinus Torvalds * Start the kernel.
1391da177e4SLinus Torvalds */
runkernel(void)1401da177e4SLinus Torvalds static void runkernel(void)
1411da177e4SLinus Torvalds {
1421da177e4SLinus Torvalds __asm__ __volatile__(
1431da177e4SLinus Torvalds "bis %1,%1,$30\n\t"
1441da177e4SLinus Torvalds "bis %0,%0,$26\n\t"
1451da177e4SLinus Torvalds "ret ($26)"
1461da177e4SLinus Torvalds : /* no outputs: it doesn't even return */
1471da177e4SLinus Torvalds : "r" (START_ADDR),
1481da177e4SLinus Torvalds "r" (PAGE_SIZE + INIT_STACK));
1491da177e4SLinus Torvalds }
1501da177e4SLinus Torvalds
start_kernel(void)1511da177e4SLinus Torvalds void start_kernel(void)
1521da177e4SLinus Torvalds {
1531da177e4SLinus Torvalds long i;
1541da177e4SLinus Torvalds long dev;
1551da177e4SLinus Torvalds int nbytes;
1561da177e4SLinus Torvalds char envval[256];
1571da177e4SLinus Torvalds
1581da177e4SLinus Torvalds srm_printk("Linux/AXP bootloader for Linux " UTS_RELEASE "\n");
1591da177e4SLinus Torvalds if (INIT_HWRPB->pagesize != 8192) {
1601da177e4SLinus Torvalds srm_printk("Expected 8kB pages, got %ldkB\n", INIT_HWRPB->pagesize >> 10);
1611da177e4SLinus Torvalds return;
1621da177e4SLinus Torvalds }
1631da177e4SLinus Torvalds pal_init();
1641da177e4SLinus Torvalds dev = openboot();
1651da177e4SLinus Torvalds if (dev < 0) {
1661da177e4SLinus Torvalds srm_printk("Unable to open boot device: %016lx\n", dev);
1671da177e4SLinus Torvalds return;
1681da177e4SLinus Torvalds }
1691da177e4SLinus Torvalds dev &= 0xffffffff;
1701da177e4SLinus Torvalds srm_printk("Loading vmlinux ...");
1711da177e4SLinus Torvalds i = load(dev, START_ADDR, KERNEL_SIZE);
1721da177e4SLinus Torvalds close(dev);
1731da177e4SLinus Torvalds if (i != KERNEL_SIZE) {
1741da177e4SLinus Torvalds srm_printk("Failed (%lx)\n", i);
1751da177e4SLinus Torvalds return;
1761da177e4SLinus Torvalds }
1771da177e4SLinus Torvalds
1781da177e4SLinus Torvalds nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval));
1791da177e4SLinus Torvalds if (nbytes < 0) {
1801da177e4SLinus Torvalds nbytes = 0;
1811da177e4SLinus Torvalds }
1821da177e4SLinus Torvalds envval[nbytes] = '\0';
1831da177e4SLinus Torvalds strcpy((char*)ZERO_PGE, envval);
1841da177e4SLinus Torvalds
1851da177e4SLinus Torvalds srm_printk(" Ok\nNow booting the kernel\n");
1861da177e4SLinus Torvalds runkernel();
1871da177e4SLinus Torvalds for (i = 0 ; i < 0x100000000 ; i++)
1881da177e4SLinus Torvalds /* nothing */;
1891da177e4SLinus Torvalds __halt();
1901da177e4SLinus Torvalds }
191