[PATCH] sh64: module support

This adds support for modules.
Signed-off-by: Richard Curnow <rc@rc0.org.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/sh64/kernel/module.c

+/*  Kernel module help for sh64.
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Copyright 2004 SuperH (UK) Ltd
+    Author: Richard Curnow
+
+    Based on the sh version, and on code from the sh64-specific parts of
+    modutils, originally written by Richard Curnow and Ben Gaster.
+
+*/
+#include <linux/moduleloader.h>
+#include <linux/elf.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+#if 0
+#define DEBUGP printk
+#else
+#define DEBUGP(fmt...)
+#endif
+
+void *module_alloc(unsigned long size)
+{
+	if (size == 0)
+		return NULL;
+	return vmalloc(size);
+}
+
+
+/* Free memory returned from module_alloc */
+void module_free(struct module *mod, void *module_region)
+{
+	vfree(module_region);
+	/* FIXME: If module_region == mod->init_region, trim exception
+           table entries. */
+}
+
+/* We don't need anything special. */
+int module_frob_arch_sections(Elf_Ehdr *hdr,
+			      Elf_Shdr *sechdrs,
+			      char *secstrings,
+			      struct module *mod)
+{
+	return 0;
+}
+
+int apply_relocate_add(Elf32_Shdr *sechdrs,
+		   const char *strtab,
+		   unsigned int symindex,
+		   unsigned int relsec,
+		   struct module *me)
+{
+	unsigned int i;
+	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
+	Elf32_Sym *sym;
+	Elf32_Addr relocation;
+	uint32_t *location;
+	int align;
+	int is_shmedia;
+
+	DEBUGP("Applying relocate section %u to %u\n", relsec,
+	       sechdrs[relsec].sh_info);
+	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+		/* This is where to make the change */
+		location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+			+ rel[i].r_offset;
+		/* This is the symbol it is referring to.  Note that all
+		   undefined symbols have been resolved.  */
+		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+			+ ELF32_R_SYM(rel[i].r_info);
+		relocation = sym->st_value + rel[i].r_addend;
+		align = (int)location & 3;
+
+		/* For text addresses, bit2 of the st_other field indicates
+		 * whether the symbol is SHmedia (1) or SHcompact (0).  If
+		 * SHmedia, the LSB of the symbol needs to be asserted
+		 * for the CPU to be in SHmedia mode when it starts executing
+		 * the branch target. */
+		is_shmedia = (sym->st_other & 4) ? 1 : 0;
+		if (is_shmedia) {
+			relocation |= 1;
+		}
+
+		switch (ELF32_R_TYPE(rel[i].r_info)) {
+		case R_SH_DIR32:
+			DEBUGP("R_SH_DIR32 @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			*location += relocation;
+			break;
+		case R_SH_REL32:
+			DEBUGP("R_SH_REL32 @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			relocation -= (Elf32_Addr) location;
+			*location += relocation;
+			break;
+		case R_SH_IMM_LOW16:
+			DEBUGP("R_SH_IMM_LOW16 @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			*location = (*location & ~0x3fffc00) |
+				((relocation & 0xffff) << 10);
+			break;
+		case R_SH_IMM_MEDLOW16:
+			DEBUGP("R_SH_IMM_MEDLOW16 @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			*location = (*location & ~0x3fffc00) |
+				(((relocation >> 16) & 0xffff) << 10);
+			break;
+		case R_SH_IMM_LOW16_PCREL:
+			DEBUGP("R_SH_IMM_LOW16_PCREL @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			relocation -= (Elf32_Addr) location;
+			*location = (*location & ~0x3fffc00) |
+				((relocation & 0xffff) << 10);
+			break;
+		case R_SH_IMM_MEDLOW16_PCREL:
+			DEBUGP("R_SH_IMM_MEDLOW16_PCREL @%08lx = %08lx\n", (unsigned long) location, (unsigned long) relocation);
+			relocation -= (Elf32_Addr) location;
+			*location = (*location & ~0x3fffc00) |
+				(((relocation >> 16) & 0xffff) << 10);
+			break;
+		default:
+			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
+			       me->name, ELF32_R_TYPE(rel[i].r_info));
+			return -ENOEXEC;
+		}
+	}
+	return 0;
+}
+
+int apply_relocate(Elf32_Shdr *sechdrs,
+		       const char *strtab,
+		       unsigned int symindex,
+		       unsigned int relsec,
+		       struct module *me)
+{
+	printk(KERN_ERR "module %s: REL RELOCATION unsupported\n",
+	       me->name);
+	return -ENOEXEC;
+}
+
+int module_finalize(const Elf_Ehdr *hdr,
+		    const Elf_Shdr *sechdrs,
+		    struct module *me)
+{
+	return 0;
+}
+
+void module_arch_cleanup(struct module *mod)
+{
+}
+

include/asm-sh64/elf.h

@@ -53,6 +53,12 @@ typedef struct user_fpu_struct elf_fpregset_t;
 
 #define ELF_ET_DYN_BASE         (2 * TASK_SIZE / 3)
 
+#define	R_SH_DIR32		1
+#define	R_SH_REL32		2
+#define	R_SH_IMM_LOW16		246
+#define	R_SH_IMM_LOW16_PCREL	247
+#define	R_SH_IMM_MEDLOW16	248
+#define	R_SH_IMM_MEDLOW16_PCREL	249
 
 #define ELF_CORE_COPY_REGS(_dest,_regs)				\
 	memcpy((char *) &_dest, (char *) _regs,			\

include/asm-sh64/module.h

@@ -4,6 +4,14 @@
  * This file contains the SH architecture specific module code.
  */
 
+struct mod_arch_specific {
+	/* empty */
+};
+
+#define Elf_Shdr		Elf32_Shdr
+#define Elf_Sym			Elf32_Sym
+#define Elf_Ehdr		Elf32_Ehdr
+
 #define module_map(x)		vmalloc(x)
 #define module_unmap(x)		vfree(x)
 #define module_arch_init(x)	(0)