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-rw-r--r--arch/alpha/boot/bootpz.c469
1 files changed, 469 insertions, 0 deletions
diff --git a/arch/alpha/boot/bootpz.c b/arch/alpha/boot/bootpz.c
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+++ b/arch/alpha/boot/bootpz.c
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+/*
+ * arch/alpha/boot/bootpz.c
+ *
+ * Copyright (C) 1997 Jay Estabrook
+ *
+ * This file is used for creating a compressed BOOTP file for the
+ * Linux/AXP kernel
+ *
+ * based significantly on the arch/alpha/boot/main.c of Linus Torvalds
+ * and the decompression code from MILO.
+ */
+#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 "kzsize.h"
+
+/* FIXME FIXME FIXME */
+#define MALLOC_AREA_SIZE 0x200000 /* 2MB for now */
+/* FIXME FIXME FIXME */
+
+
+/*
+ WARNING NOTE
+
+ It is very possible that turning on additional messages may cause
+ kernel image corruption due to stack usage to do the printing.
+
+*/
+
+#undef DEBUG_CHECK_RANGE
+#undef DEBUG_ADDRESSES
+#undef DEBUG_LAST_STEPS
+
+extern unsigned long switch_to_osf_pal(unsigned long nr,
+ struct pcb_struct * pcb_va, struct pcb_struct * pcb_pa,
+ unsigned long *vptb);
+
+extern int decompress_kernel(void* destination, void *source,
+ size_t ksize, size_t kzsize);
+
+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.
+ */
+#define VPTB ((unsigned long *) 0x200000000)
+
+static inline unsigned long
+find_pa(unsigned long address)
+{
+ unsigned long result;
+
+ result = VPTB[address >> 13];
+ result >>= 32;
+ result <<= 13;
+ result |= address & 0x1fff;
+ return result;
+}
+
+int
+check_range(unsigned long vstart, unsigned long vend,
+ unsigned long kstart, unsigned long kend)
+{
+ unsigned long vaddr, kaddr;
+
+#ifdef DEBUG_CHECK_RANGE
+ srm_printk("check_range: V[0x%lx:0x%lx] K[0x%lx:0x%lx]\n",
+ vstart, vend, kstart, kend);
+#endif
+ /* do some range checking for detecting an overlap... */
+ for (vaddr = vstart; vaddr <= vend; vaddr += PAGE_SIZE)
+ {
+ kaddr = (find_pa(vaddr) | PAGE_OFFSET);
+ if (kaddr >= kstart && kaddr <= kend)
+ {
+#ifdef DEBUG_CHECK_RANGE
+ srm_printk("OVERLAP: vaddr 0x%lx kaddr 0x%lx"
+ " [0x%lx:0x%lx]\n",
+ vaddr, kaddr, kstart, kend);
+#endif
+ return 1;
+ }
+ }
+ return 0;
+}
+
+/*
+ * 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 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 = (struct pcb_struct *)find_pa((unsigned long)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 */
+}
+
+/*
+ * 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));
+}
+
+/* Must record the SP (it is virtual) on entry, so we can make sure
+ not to overwrite it during movement or decompression. */
+unsigned long SP_on_entry;
+
+/* Calculate the kernel image address based on the end of the BOOTP
+ bootstrapper (ie this program).
+*/
+extern char _end;
+#define KERNEL_ORIGIN \
+ ((((unsigned long)&_end) + 511) & ~511)
+
+/* Round address to next higher page boundary. */
+#define NEXT_PAGE(a) (((a) | (PAGE_SIZE - 1)) + 1)
+
+#ifdef INITRD_IMAGE_SIZE
+# define REAL_INITRD_SIZE INITRD_IMAGE_SIZE
+#else
+# define REAL_INITRD_SIZE 0
+#endif
+
+/* Defines from include/asm-alpha/system.h
+
+ BOOT_ADDR Virtual address at which the consoles loads
+ the BOOTP image.
+
+ KERNEL_START KSEG address at which the kernel is built to run,
+ which includes some initial data pages before the
+ code.
+
+ START_ADDR KSEG address of the entry point of kernel code.
+
+ ZERO_PGE KSEG address of page full of zeroes, but
+ upon entry to kerne cvan be expected
+ to hold the parameter list and possible
+ INTRD information.
+
+ These are used in the local defines below.
+*/
+
+
+/* Virtual addresses for the BOOTP image. Note that this includes the
+ bootstrapper code as well as the compressed kernel image, and
+ possibly the INITRD image.
+
+ Oh, and do NOT forget the STACK, which appears to be placed virtually
+ beyond the end of the loaded image.
+*/
+#define V_BOOT_IMAGE_START BOOT_ADDR
+#define V_BOOT_IMAGE_END SP_on_entry
+
+/* Virtual addresses for just the bootstrapper part of the BOOTP image. */
+#define V_BOOTSTRAPPER_START BOOT_ADDR
+#define V_BOOTSTRAPPER_END KERNEL_ORIGIN
+
+/* Virtual addresses for just the data part of the BOOTP
+ image. This may also include the INITRD image, but always
+ includes the STACK.
+*/
+#define V_DATA_START KERNEL_ORIGIN
+#define V_INITRD_START (KERNEL_ORIGIN + KERNEL_Z_SIZE)
+#define V_INTRD_END (V_INITRD_START + REAL_INITRD_SIZE)
+#define V_DATA_END V_BOOT_IMAGE_END
+
+/* KSEG addresses for the uncompressed kernel.
+
+ Note that the end address includes workspace for the decompression.
+ Note also that the DATA_START address is ZERO_PGE, to which we write
+ just before jumping to the kernel image at START_ADDR.
+ */
+#define K_KERNEL_DATA_START ZERO_PGE
+#define K_KERNEL_IMAGE_START START_ADDR
+#define K_KERNEL_IMAGE_END (START_ADDR + KERNEL_SIZE)
+
+/* Define to where we may have to decompress the kernel image, before
+ we move it to the final position, in case of overlap. This will be
+ above the final position of the kernel.
+
+ Regardless of overlap, we move the INITRD image to the end of this
+ copy area, because there needs to be a buffer area after the kernel
+ for "bootmem" anyway.
+*/
+#define K_COPY_IMAGE_START NEXT_PAGE(K_KERNEL_IMAGE_END)
+/* Reserve one page below INITRD for the new stack. */
+#define K_INITRD_START \
+ NEXT_PAGE(K_COPY_IMAGE_START + KERNEL_SIZE + PAGE_SIZE)
+#define K_COPY_IMAGE_END \
+ (K_INITRD_START + REAL_INITRD_SIZE + MALLOC_AREA_SIZE)
+#define K_COPY_IMAGE_SIZE \
+ NEXT_PAGE(K_COPY_IMAGE_END - K_COPY_IMAGE_START)
+
+void
+start_kernel(void)
+{
+ int must_move = 0;
+
+ /* Initialize these for the decompression-in-place situation,
+ which is the smallest amount of work and most likely to
+ occur when using the normal START_ADDR of the kernel
+ (currently set to 16MB, to clear all console code.
+ */
+ unsigned long uncompressed_image_start = K_KERNEL_IMAGE_START;
+ unsigned long uncompressed_image_end = K_KERNEL_IMAGE_END;
+
+ unsigned long initrd_image_start = K_INITRD_START;
+
+ /*
+ * 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)));
+ register unsigned long asm_sp asm("30");
+
+ SP_on_entry = asm_sp;
+
+ srm_printk("Linux/Alpha BOOTPZ Loader for Linux " UTS_RELEASE "\n");
+
+ /* Validity check the HWRPB. */
+ 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;
+ }
+
+ /* PALcode (re)initialization. */
+ pal_init();
+
+ /* Get the parameter list from the console environment variable. */
+ nbytes = callback_getenv(ENV_BOOTED_OSFLAGS, envval, sizeof(envval));
+ if (nbytes < 0 || nbytes >= sizeof(envval)) {
+ nbytes = 0;
+ }
+ envval[nbytes] = '\0';
+
+#ifdef DEBUG_ADDRESSES
+ srm_printk("START_ADDR 0x%lx\n", START_ADDR);
+ srm_printk("KERNEL_ORIGIN 0x%lx\n", KERNEL_ORIGIN);
+ srm_printk("KERNEL_SIZE 0x%x\n", KERNEL_SIZE);
+ srm_printk("KERNEL_Z_SIZE 0x%x\n", KERNEL_Z_SIZE);
+#endif
+
+ /* Since all the SRM consoles load the BOOTP image at virtual
+ * 0x20000000, we have to ensure that the physical memory
+ * pages occupied by that image do NOT overlap the physical
+ * address range where the kernel wants to be run. This
+ * causes real problems when attempting to cdecompress the
+ * former into the latter... :-(
+ *
+ * So, we may have to decompress/move the kernel/INITRD image
+ * virtual-to-physical someplace else first before moving
+ * kernel /INITRD to their final resting places... ;-}
+ *
+ * Sigh...
+ */
+
+ /* First, check to see if the range of addresses occupied by
+ the bootstrapper part of the BOOTP image include any of the
+ physical pages into which the kernel will be placed for
+ execution.
+
+ We only need check on the final kernel image range, since we
+ will put the INITRD someplace that we can be sure is not
+ in conflict.
+ */
+ if (check_range(V_BOOTSTRAPPER_START, V_BOOTSTRAPPER_END,
+ K_KERNEL_DATA_START, K_KERNEL_IMAGE_END))
+ {
+ srm_printk("FATAL ERROR: overlap of bootstrapper code\n");
+ __halt();
+ }
+
+ /* Next, check to see if the range of addresses occupied by
+ the compressed kernel/INITRD/stack portion of the BOOTP
+ image include any of the physical pages into which the
+ decompressed kernel or the INITRD will be placed for
+ execution.
+ */
+ if (check_range(V_DATA_START, V_DATA_END,
+ K_KERNEL_IMAGE_START, K_COPY_IMAGE_END))
+ {
+#ifdef DEBUG_ADDRESSES
+ srm_printk("OVERLAP: cannot decompress in place\n");
+#endif
+ uncompressed_image_start = K_COPY_IMAGE_START;
+ uncompressed_image_end = K_COPY_IMAGE_END;
+ must_move = 1;
+
+ /* Finally, check to see if the range of addresses
+ occupied by the compressed kernel/INITRD part of
+ the BOOTP image include any of the physical pages
+ into which that part is to be copied for
+ decompression.
+ */
+ while (check_range(V_DATA_START, V_DATA_END,
+ uncompressed_image_start,
+ uncompressed_image_end))
+ {
+#if 0
+ uncompressed_image_start += K_COPY_IMAGE_SIZE;
+ uncompressed_image_end += K_COPY_IMAGE_SIZE;
+ initrd_image_start += K_COPY_IMAGE_SIZE;
+#else
+ /* Keep as close as possible to end of BOOTP image. */
+ uncompressed_image_start += PAGE_SIZE;
+ uncompressed_image_end += PAGE_SIZE;
+ initrd_image_start += PAGE_SIZE;
+#endif
+ }
+ }
+
+ srm_printk("Starting to load the kernel with args '%s'\n", envval);
+
+#ifdef DEBUG_ADDRESSES
+ srm_printk("Decompressing the kernel...\n"
+ "...from 0x%lx to 0x%lx size 0x%x\n",
+ V_DATA_START,
+ uncompressed_image_start,
+ KERNEL_SIZE);
+#endif
+ decompress_kernel((void *)uncompressed_image_start,
+ (void *)V_DATA_START,
+ KERNEL_SIZE, KERNEL_Z_SIZE);
+
+ /*
+ * Now, move things to their final positions, if/as required.
+ */
+
+#ifdef INITRD_IMAGE_SIZE
+
+ /* First, we always move the INITRD image, if present. */
+#ifdef DEBUG_ADDRESSES
+ srm_printk("Moving the INITRD image...\n"
+ " from 0x%lx to 0x%lx size 0x%x\n",
+ V_INITRD_START,
+ initrd_image_start,
+ INITRD_IMAGE_SIZE);
+#endif
+ memcpy((void *)initrd_image_start, (void *)V_INITRD_START,
+ INITRD_IMAGE_SIZE);
+
+#endif /* INITRD_IMAGE_SIZE */
+
+ /* Next, we may have to move the uncompressed kernel to the
+ final destination.
+ */
+ if (must_move) {
+#ifdef DEBUG_ADDRESSES
+ srm_printk("Moving the uncompressed kernel...\n"
+ "...from 0x%lx to 0x%lx size 0x%x\n",
+ uncompressed_image_start,
+ K_KERNEL_IMAGE_START,
+ (unsigned)KERNEL_SIZE);
+#endif
+ /*
+ * Move the stack to a safe place to ensure it won't be
+ * overwritten by kernel image.
+ */
+ move_stack(initrd_image_start - PAGE_SIZE);
+
+ memcpy((void *)K_KERNEL_IMAGE_START,
+ (void *)uncompressed_image_start, KERNEL_SIZE);
+ }
+
+ /* Clear the zero page, then move the argument list in. */
+#ifdef DEBUG_LAST_STEPS
+ srm_printk("Preparing ZERO_PGE...\n");
+#endif
+ memset((char*)ZERO_PGE, 0, PAGE_SIZE);
+ strcpy((char*)ZERO_PGE, envval);
+
+#ifdef INITRD_IMAGE_SIZE
+
+#ifdef DEBUG_LAST_STEPS
+ srm_printk("Preparing INITRD info...\n");
+#endif
+ /* Finally, set the INITRD paramenters for the kernel. */
+ ((long *)(ZERO_PGE+256))[0] = initrd_image_start;
+ ((long *)(ZERO_PGE+256))[1] = INITRD_IMAGE_SIZE;
+
+#endif /* INITRD_IMAGE_SIZE */
+
+#ifdef DEBUG_LAST_STEPS
+ srm_printk("Doing 'runkernel()'...\n");
+#endif
+ runkernel();
+}