Add 2 new archsw interfaces:

1.  arch_loadaddr - used by platform code to adjust the address at which
    the object gets loaded. Implement PC98 using this new interface instead
    of using conditional compilation. For ELF objects the ELF header is
    passed as the data pointer. For raw files it's the filename. Note that
    ELF objects are first considered as raw files.
2.  arch_loadseg - used by platform code to keep track of actual segments,
    so that (instruction) caches can be flushed or translations can be
    created. Both the ELF header as well as the program header are passed
    to allow platform code to treat the kernel proper differently from any
    additional modules and to have all the relevant details of the loaded
    segment (e.g. protection).

sys/boot/common/bootstrap.h

@@ -296,6 +296,24 @@ struct arch_switch
     /* Perform ISA byte port I/O (only for systems with ISA) */
     int		(*arch_isainb)(int port);
     void	(*arch_isaoutb)(int port, int value);
+
+    /*
+     * Interface to adjust the load address according to the "object"
+     * being loaded.
+     */
+    uint64_t	(*arch_loadaddr)(u_int type, void *data, uint64_t addr);
+#define	LOAD_ELF	1	/* data points to the ELF header. */
+#define	LOAD_RAW	2	/* data points to the file name. */
+
+    /*
+     * Interface to inform MD code about a loaded (ELF) segment. This
+     * can be used to flush caches and/or set up translations.
+     */
+#ifdef __elfN
+    void	(*arch_loadseg)(Elf_Ehdr *eh, Elf_Phdr *ph, uint64_t delta);
+#else
+    void	(*arch_loadseg)(void *eh, void *ph, uint64_t delta);
+#endif
 };
 extern struct arch_switch archsw;
 

sys/boot/common/load_elf.c

@@ -97,7 +97,6 @@ __elfN(loadfile)(char *filename, u_int64_t dest, struct preloaded_file **result)
     struct elf_file		ef;
     Elf_Ehdr 			*ehdr;
     int				err;
-    u_int			pad;
     ssize_t			bytes_read;
 
     fp = NULL;
@@ -157,12 +156,6 @@ __elfN(loadfile)(char *filename, u_int64_t dest, struct preloaded_file **result)
 	/* Looks OK, got ahead */
 	ef.kernel = 0;
 
-	/* Page-align the load address */
-	pad = (u_int)dest & PAGE_MASK;
-	if (pad != 0) {
-	    pad = PAGE_SIZE - pad;
-	    dest += pad;
-	}
     } else if (ehdr->e_type == ET_EXEC) {
 	/* Looks like a kernel */
 	if (kfp != NULL) {
@@ -173,7 +166,7 @@ __elfN(loadfile)(char *filename, u_int64_t dest, struct preloaded_file **result)
 	/* 
 	 * Calculate destination address based on kernel entrypoint 	
 	 */
-	dest = ehdr->e_entry;
+	dest = (ehdr->e_entry & ~PAGE_MASK);
 	if (dest == 0) {
 	    printf("elf" __XSTRING(__ELF_WORD_SIZE) "_loadfile: not a kernel (maybe static binary?)\n");
 	    err = EPERM;
@@ -186,6 +179,11 @@ __elfN(loadfile)(char *filename, u_int64_t dest, struct preloaded_file **result)
 	goto oerr;
     }
 
+    if (archsw.arch_loadaddr != NULL)
+	dest = archsw.arch_loadaddr(LOAD_ELF, ehdr, dest);
+    else
+	dest = roundup(dest, PAGE_SIZE);
+
     /* 
      * Ok, we think we should handle this.
      */
@@ -202,7 +200,7 @@ __elfN(loadfile)(char *filename, u_int64_t dest, struct preloaded_file **result)
 
 #ifdef ELF_VERBOSE
     if (ef.kernel)
-	printf("%s entry at 0x%jx\n", filename, (uintmax_t)dest);
+	printf("%s entry at 0x%jx\n", filename, (uintmax_t)ehdr->e_entry);
 #else
     printf("%s ", filename);
 #endif
@@ -362,6 +360,9 @@ __elfN(loadimage)(struct preloaded_file *fp, elf_file_t ef, u_int64_t off)
 	printf("\n");
 #endif
 
+	if (archsw.arch_loadseg != NULL)
+	    archsw.arch_loadseg(ehdr, phdr + i, off);
+
 	if (firstaddr == 0 || firstaddr > (phdr[i].p_vaddr + off))
 	    firstaddr = phdr[i].p_vaddr + off;
 	if (lastaddr == 0 || lastaddr < (phdr[i].p_vaddr + off + phdr[i].p_memsz))

sys/boot/common/load_elf_obj.c

@@ -144,8 +144,10 @@ __elfN(obj_loadfile)(char *filename, u_int64_t dest,
 		goto oerr;
 	}
 
-	/* Page-align the load address */
-	dest = roundup(dest, PAGE_SIZE);
+	if (archsw.arch_loadaddr != NULL)
+		dest = archsw.arch_loadaddr(LOAD_ELF, hdr, dest);
+	else
+		dest = roundup(dest, PAGE_SIZE);
 
 	/*
 	 * Ok, we think we should handle this.

sys/boot/common/module.c

@@ -275,6 +275,9 @@ file_load(char *filename, vm_offset_t dest, struct preloaded_file **result)
     int error;
     int i;
 
+    if (archsw.arch_loadaddr != NULL)
+	dest = archsw.arch_loadaddr(LOAD_RAW, filename, dest);
+
     error = EFTYPE;
     for (i = 0, fp = NULL; file_formats[i] && fp == NULL; i++) {
 	error = (file_formats[i]->l_load)(filename, loadaddr, &fp);
@@ -352,9 +355,6 @@ file_loadraw(char *type, char *name)
     char			*cp;
     int				fd, got;
     vm_offset_t			laddr;
-#ifdef PC98
-    struct stat			st;
-#endif
 
     /* We can't load first */
     if ((file_findfile(NULL, NULL)) == NULL) {
@@ -369,20 +369,15 @@ file_loadraw(char *type, char *name)
 	return(CMD_ERROR);
     }
     name = cp;
-    
+
     if ((fd = open(name, O_RDONLY)) < 0) {
 	sprintf(command_errbuf, "can't open '%s': %s", name, strerror(errno));
 	free(name);
 	return(CMD_ERROR);
     }
 
-#ifdef PC98
-    /* We cannot use 15M-16M area on pc98. */
-    if (loadaddr < 0x1000000 &&
-	fstat(fd, &st) == 0 &&
-	(st.st_size == -1 || loadaddr + st.st_size > 0xf00000))
-	loadaddr = 0x1000000;
-#endif
+    if (archsw.arch_loadaddr != NULL)
+	loadaddr = archsw.arch_loadaddr(LOAD_RAW, name, loadaddr);
 
     laddr = loadaddr;
     for (;;) {
@@ -489,14 +484,6 @@ mod_loadkld(const char *kldname, int argc, char *argv[])
 	;
 
     do {
-#ifdef PC98
-	/* We cannot use 15M-16M area on pc98. */
-	struct stat st;
-	if (loadaddr < 0x1000000 &&
-	    stat(filename, &st) == 0 &&
-	    (st.st_size == -1 || loadaddr + st.st_size > 0xf00000))
-	    loadaddr = 0x1000000;
-#endif
 	err = file_load(filename, loadaddr, &fp);
 	if (err)
 	    break;

sys/boot/pc98/loader/main.c

@@ -36,6 +36,7 @@ __FBSDID("$FreeBSD$");
 #include <string.h>
 #include <machine/bootinfo.h>
 #include <machine/psl.h>
+#include <sys/param.h>
 #include <sys/reboot.h>
 
 #include "bootstrap.h"
@@ -77,6 +78,21 @@ extern char end[];
 static void *heap_top;
 static void *heap_bottom;
 
+static uint64_t
+pc98_loadaddr(u_int type, void *data, uint64_t addr)
+{
+	struct stat st;
+
+	if (type == LOAD_ELF)
+		return (roundup(addr, PAGE_SIZE));
+
+	/* We cannot use 15M-16M area on pc98. */
+	if (type == LOAD_RAW && addr < 0x1000000 && stat(data, &st) == 0 &&
+	    (st.st_size == -1 || addr + st.st_size > 0xf00000))
+		addr = 0x1000000;
+	return (addr);
+}
+
 int
 main(void)
 {
@@ -160,6 +176,7 @@ main(void)
     archsw.arch_readin = i386_readin;
     archsw.arch_isainb = isa_inb;
     archsw.arch_isaoutb = isa_outb;
+    archsw.arch_loadaddr = pc98_loadaddr;
 
     /*
      * March through the device switch probing for things.