patch-2.4.23 linux-2.4.23/arch/alpha/boot/bootpz.c

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diff -urN linux-2.4.22/arch/alpha/boot/bootpz.c linux-2.4.23/arch/alpha/boot/bootpz.c
@@ -0,0 +1,447 @@
+/*
+ * 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 */
+
+
+#undef DEBUG_CHECK_RANGE
+#define DEBUG_ADDRESSES
+
+#define DEBUG_SP(x) \
+    {register long sp asm("30"); srm_printk("%s (sp=%lx)\n", x, sp);}
+
+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);
+
+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 %1,%1,$30\n\t"
+		"bis %0,%0,$27\n\t"
+		"jmp ($27)"
+		: /* no outputs: it doesn't even return */
+		: "r" (START_ADDR),
+		  "r" (PAGE_SIZE + INIT_STACK));
+}
+
+/* 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)
+#define K_INITRD_START		NEXT_PAGE(K_COPY_IMAGE_START + KERNEL_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
+		memcpy((void *)K_KERNEL_IMAGE_START,
+		       (void *)uncompressed_image_start,
+		       KERNEL_SIZE);
+	}
+	
+	/* Clear the zero page, then move the argument list in. */
+	memset((char*)ZERO_PGE, 0, PAGE_SIZE);
+	strcpy((char*)ZERO_PGE, envval);
+
+#ifdef INITRD_IMAGE_SIZE
+	/* 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 */
+
+	runkernel();
+}

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