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-rw-r--r--arch/alpha/boot/main.c190
1 files changed, 190 insertions, 0 deletions
diff --git a/arch/alpha/boot/main.c b/arch/alpha/boot/main.c
new file mode 100644
index 0000000000..22a1cb0264
--- /dev/null
+++ b/arch/alpha/boot/main.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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/slab.h>
+#include <linux/string.h>
+#include <generated/utsrelease.h>
+#include <linux/mm.h>
+
+#include <asm/console.h>
+#include <asm/hwrpb.h>
+
+#include <linux/stdarg.h>
+
+#include "ksize.h"
+
+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, (void *)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();
+}