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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/alpha/boot/bootp.c
downloadconfigs-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/alpha/boot/bootp.c')
-rw-r--r--arch/alpha/boot/bootp.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/arch/alpha/boot/bootp.c b/arch/alpha/boot/bootp.c
new file mode 100644
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+++ b/arch/alpha/boot/bootp.c
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+/*
+ * arch/alpha/boot/bootp.c
+ *
+ * Copyright (C) 1997 Jay Estabrook
+ *
+ * This file is used for creating a bootp file for the Linux/AXP kernel
+ *
+ * based significantly on the arch/alpha/boot/main.c of Linus Torvalds
+ */
+#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 <asm/io.h>
+
+#include <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);
+
+extern void move_stack(unsigned long new_stack);
+
+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 void
+load(unsigned long dst, unsigned long src, unsigned long count)
+{
+ memcpy((void *)dst, (void *)src, count);
+}
+
+/*
+ * Start the kernel.
+ */
+static inline void
+runkernel(void)
+{
+ __asm__ __volatile__(
+ "bis %0,%0,$27\n\t"
+ "jmp ($27)"
+ : /* no outputs: it doesn't even return */
+ : "r" (START_ADDR));
+}
+
+extern char _end;
+#define KERNEL_ORIGIN \
+ ((((unsigned long)&_end) + 511) & ~511)
+
+void
+start_kernel(void)
+{
+ /*
+ * Note that this crufty stuff with static and envval
+ * and envbuf is because:
+ *
+ * 1. Frequently, the stack is short, and we don't want to overrun;
+ * 2. Frequently the stack is where we are going to copy the kernel to;
+ * 3. A certain SRM console required the GET_ENV output to stack.
+ * ??? A comment in the aboot sources indicates that the GET_ENV
+ * destination must be quadword aligned. Might this explain the
+ * behaviour, rather than requiring output to the stack, which
+ * seems rather far-fetched.
+ */
+ static long nbytes;
+ static char envval[256] __attribute__((aligned(8)));
+ static unsigned long initrd_start;
+
+ srm_printk("Linux/AXP bootp loader for Linux " UTS_RELEASE "\n");
+ if (INIT_HWRPB->pagesize != 8192) {
+ srm_printk("Expected 8kB pages, got %ldkB\n",
+ INIT_HWRPB->pagesize >> 10);
+ return;
+ }
+ if (INIT_HWRPB->vptb != (unsigned long) VPTB) {
+ srm_printk("Expected vptb at %p, got %p\n",
+ VPTB, (void *)INIT_HWRPB->vptb);
+ return;
+ }
+ pal_init();
+
+ /* The initrd must be page-aligned. See below for the
+ cause of the magic number 5. */
+ initrd_start = ((START_ADDR + 5*KERNEL_SIZE + PAGE_SIZE) |
+ (PAGE_SIZE-1)) + 1;
+#ifdef INITRD_IMAGE_SIZE
+ srm_printk("Initrd positioned at %#lx\n", initrd_start);
+#endif
+
+ /*
+ * Move the stack to a safe place to ensure it won't be
+ * overwritten by kernel image.
+ */
+ move_stack(initrd_start - PAGE_SIZE);
+
+ nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval));
+ if (nbytes < 0 || nbytes >= sizeof(envval)) {
+ nbytes = 0;
+ }
+ envval[nbytes] = '\0';
+ srm_printk("Loading the kernel...'%s'\n", envval);
+
+ /* NOTE: *no* callbacks or printouts from here on out!!! */
+
+ /* This is a hack, as some consoles seem to get virtual 20000000 (ie
+ * where the SRM console puts the kernel bootp image) memory
+ * overlapping physical memory where the kernel wants to be put,
+ * which causes real problems when attempting to copy the former to
+ * the latter... :-(
+ *
+ * So, we first move the kernel virtual-to-physical way above where
+ * we physically want the kernel to end up, then copy it from there
+ * to its final resting place... ;-}
+ *
+ * Sigh... */
+
+#ifdef INITRD_IMAGE_SIZE
+ load(initrd_start, KERNEL_ORIGIN+KERNEL_SIZE, INITRD_IMAGE_SIZE);
+#endif
+ load(START_ADDR+(4*KERNEL_SIZE), KERNEL_ORIGIN, KERNEL_SIZE);
+ load(START_ADDR, START_ADDR+(4*KERNEL_SIZE), KERNEL_SIZE);
+
+ memset((char*)ZERO_PGE, 0, PAGE_SIZE);
+ strcpy((char*)ZERO_PGE, envval);
+#ifdef INITRD_IMAGE_SIZE
+ ((long *)(ZERO_PGE+256))[0] = initrd_start;
+ ((long *)(ZERO_PGE+256))[1] = INITRD_IMAGE_SIZE;
+#endif
+
+ runkernel();
+}