1 files changed, 469 insertions, 0 deletions

diff --git a/arch/alpha/boot/bootpz.c b/arch/alpha/boot/bootpz.c
new file mode 100644
index 000000000000..a6657f2cf9bd
--- /dev/null
+++ b/arch/alpha/boot/bootpz.c
@@ -0,0 +1,469 @@
+/*
+ * 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();
+}