add blackfin specific bits for module handling

4 files changed, 317 insertions, 1 deletions

diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index 0192b2e920..f70df95680 100644
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -1,6 +1,8 @@
 
 config BLACKFIN
 	bool
+	select HAS_KALLSYMS
+	select HAS_MODULE
 	default y
 
 config BF561
diff --git a/arch/blackfin/Makefile b/arch/blackfin/Makefile
index 0fe24fea61..a3a1cf53f8 100644
--- a/arch/blackfin/Makefile
+++ b/arch/blackfin/Makefile
@@ -11,7 +11,9 @@ TEXT_BASE = $(CONFIG_TEXT_BASE)
 
 CPPFLAGS += -DTEXT_BASE=$(TEXT_BASE) -P
 CFLAGS := -fno-common -Os -D__blackfin__
-LDFLAGS_uboot  :=-L $(shell dirname `$(CC) $(CFLAGS) -print-libgcc-file-name`) -lgcc -Ttext $(TEXT_BASE)
+LDFLAGS_uboot  :=-L $(shell dirname `$(CC) $(CFLAGS) -print-libgcc-file-name`) -lgcc 
+# -Ttext $(TEXT_BASE)
+KALLSYMS         += --symbol-prefix=_
 
 ifeq ($(incdir-y),)
 incdir-y := $(machine-y)
diff --git a/arch/blackfin/lib/Makefile b/arch/blackfin/lib/Makefile
index 3f625b77d2..286f138e3c 100644
--- a/arch/blackfin/lib/Makefile
+++ b/arch/blackfin/lib/Makefile
@@ -14,3 +14,4 @@ obj-y += cpu.o
 obj-y += flush.o
 obj-y += interrupt.o
 obj-y += traps.o
+obj-$(CONFIG_MODULE) += module.o
diff --git a/arch/blackfin/lib/module.c b/arch/blackfin/lib/module.c
new file mode 100644
index 0000000000..a82d0a9137
--- /dev/null
+++ b/arch/blackfin/lib/module.c
@@ -0,0 +1,311 @@
+/*
+ * File:         arch/blackfin/kernel/module.c
+ * Based on:
+ * Author:
+ *
+ * Created:
+ * Description:
+ *
+ * Modified:
+ *               Copyright 2004-2006 Analog Devices Inc.
+ *
+ * Bugs:         Enter bugs at http://blackfin.uclinux.org/
+ *
+ * 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, see the file COPYING, or write
+ * to the Free Software Foundation, Inc.,
+ * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <common.h>
+#include <elf.h>
+#include <module.h>
+#include <malloc.h>
+#include <errno.h>
+
+/*
+ * handle arithmetic relocations.
+ * See binutils/bfd/elf32-bfin.c for more details
+ */
+#define RELOC_STACK_SIZE 100
+static uint32_t reloc_stack[RELOC_STACK_SIZE];
+static unsigned int reloc_stack_tos;
+
+#define is_reloc_stack_empty() ((reloc_stack_tos > 0)?0:1)
+
+static void reloc_stack_push(uint32_t value)
+{
+	reloc_stack[reloc_stack_tos++] = value;
+}
+
+static uint32_t reloc_stack_pop(void)
+{
+	return reloc_stack[--reloc_stack_tos];
+}
+
+static uint32_t reloc_stack_operate(unsigned int oper, struct module *mod)
+{
+	uint32_t value;
+
+	switch (oper) {
+	case R_add:
+		value = reloc_stack[reloc_stack_tos - 2] +
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_sub:
+		value = reloc_stack[reloc_stack_tos - 2] -
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_mult:
+		value = reloc_stack[reloc_stack_tos - 2] *
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_div:
+		value = reloc_stack[reloc_stack_tos - 2] /
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_mod:
+		value = reloc_stack[reloc_stack_tos - 2] %
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_lshift:
+		value = reloc_stack[reloc_stack_tos - 2] <<
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_rshift:
+		value = reloc_stack[reloc_stack_tos - 2] >>
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_and:
+		value = reloc_stack[reloc_stack_tos - 2] &
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_or:
+		value = reloc_stack[reloc_stack_tos - 2] |
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_xor:
+		value = reloc_stack[reloc_stack_tos - 2] ^
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_land:
+		value = reloc_stack[reloc_stack_tos - 2] &&
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_lor:
+		value = reloc_stack[reloc_stack_tos - 2] ||
+			reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 2;
+		break;
+	case R_neg:
+		value = -reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos--;
+		break;
+	case R_comp:
+		value = ~reloc_stack[reloc_stack_tos - 1];
+		reloc_stack_tos -= 1;
+		break;
+	default:
+		printf("module %s: unhandled reloction\n",
+				mod->name);
+		return 0;
+	}
+
+	/* now push the new value back on stack */
+	reloc_stack_push(value);
+
+	return value;
+}
+
+int
+apply_relocate(Elf_Shdr * sechdrs, const char *strtab,
+	       unsigned int symindex, unsigned int relsec, struct module *me)
+{
+	printf("module %s: .rel unsupported\n", me->name);
+	return -ENOEXEC;
+}
+
+/*************************************************************************/
+/* FUNCTION : apply_relocate_add                                         */
+/* ABSTRACT : Blackfin specific relocation handling for the loadable     */
+/*            modules. Modules are expected to be .o files.              */
+/*            Arithmetic relocations are handled.                        */
+/*            We do not expect LSETUP to be split and hence is not       */
+/*            handled.                                                   */
+/*            R_byte and R_byte2 are also not handled as the gas         */
+/*            does not generate it.                                      */
+/*************************************************************************/
+int
+apply_relocate_add(Elf_Shdr * sechdrs, const char *strtab,
+		   unsigned int symindex, unsigned int relsec,
+		   struct module *mod)
+{
+	unsigned int i;
+	unsigned short tmp;
+	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
+	Elf32_Sym *sym;
+	uint32_t *location32;
+	uint16_t *location16;
+	uint32_t value;
+
+	debug("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 */
+		location16 =
+		    (uint16_t *) (sechdrs[sechdrs[relsec].sh_info].sh_addr +
+				  rel[i].r_offset);
+		location32 = (uint32_t *) location16;
+		/* 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);
+		if (is_reloc_stack_empty()) {
+			value = sym->st_value;
+		} else {
+			value = reloc_stack_pop();
+		}
+		value += rel[i].r_addend;
+		debug("location is %x, value is %x type is %d \n",
+			 (unsigned int) location32, value,
+			 ELF32_R_TYPE(rel[i].r_info));
+
+		switch (ELF32_R_TYPE(rel[i].r_info)) {
+
+		case R_pcrel24:
+		case R_pcrel24_jump_l:
+			/* Add the value, subtract its postition */
+			location16 =
+			    (uint16_t *) (sechdrs[sechdrs[relsec].sh_info].
+					  sh_addr + rel[i].r_offset - 2);
+			location32 = (uint32_t *) location16;
+			value -= (uint32_t) location32;
+			value >>= 1;
+			debug("value is %x, before %x-%x after %x-%x\n", value,
+			       *location16, *(location16 + 1),
+			       (*location16 & 0xff00) | (value >> 16 & 0x00ff),
+			       value & 0xffff);
+			*location16 =
+			    (*location16 & 0xff00) | (value >> 16 & 0x00ff);
+			*(location16 + 1) = value & 0xffff;
+			break;
+		case R_pcrel12_jump:
+		case R_pcrel12_jump_s:
+			value -= (uint32_t) location32;
+			value >>= 1;
+			*location16 = (value & 0xfff);
+			break;
+		case R_pcrel10:
+			value -= (uint32_t) location32;
+			value >>= 1;
+			*location16 = (value & 0x3ff);
+			break;
+		case R_luimm16:
+			debug("before %x after %x\n", *location16,
+				       (value & 0xffff));
+			tmp = (value & 0xffff);
+			*location16 = tmp;
+			break;
+		case R_huimm16:
+			debug("before %x after %x\n", *location16,
+				       ((value >> 16) & 0xffff));
+			tmp = ((value >> 16) & 0xffff);
+			*location16 = tmp;
+			break;
+		case R_rimm16:
+			*location16 = (value & 0xffff);
+			break;
+		case R_byte4_data:
+			debug("before %x after %x\n", *location32, value);
+			*location32 = value;
+			break;
+		case R_push:
+			reloc_stack_push(value);
+			break;
+		case R_const:
+			reloc_stack_push(rel[i].r_addend);
+			break;
+		case R_add:
+		case R_sub:
+		case R_mult:
+		case R_div:
+		case R_mod:
+		case R_lshift:
+		case R_rshift:
+		case R_and:
+		case R_or:
+		case R_xor:
+		case R_land:
+		case R_lor:
+		case R_neg:
+		case R_comp:
+			reloc_stack_operate(ELF32_R_TYPE(rel[i].r_info), mod);
+			break;
+		default:
+			printf("module %s: Unknown relocation: %u\n",
+			       mod->name, ELF32_R_TYPE(rel[i].r_info));
+			return -ENOEXEC;
+		}
+	}
+	return 0;
+}
+
+#if 0
+int
+module_finalize(const Elf_Ehdr * hdr,
+		const Elf_Shdr * sechdrs, struct module *mod)
+{
+	unsigned int i, strindex = 0, symindex = 0;
+	char *secstrings;
+
+	secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+
+	for (i = 1; i < hdr->e_shnum; i++) {
+		/* Internal symbols and strings. */
+		if (sechdrs[i].sh_type == SHT_SYMTAB) {
+			symindex = i;
+			strindex = sechdrs[i].sh_link;
+		}
+	}
+
+	for (i = 1; i < hdr->e_shnum; i++) {
+		const char *strtab = (char *)sechdrs[strindex].sh_addr;
+		unsigned int info = sechdrs[i].sh_info;
+
+		/* Not a valid relocation section? */
+		if (info >= hdr->e_shnum)
+			continue;
+
+		if ((sechdrs[i].sh_type == SHT_RELA) &&
+		    ((strcmp(".rela.l1.text", secstrings + sechdrs[i].sh_name) == 0) ||
+		    ((strcmp(".rela.text", secstrings + sechdrs[i].sh_name) == 0) &&
+			 (hdr->e_flags & FLG_CODE_IN_L1)))) {
+			apply_relocate_add((Elf_Shdr *) sechdrs, strtab,
+					   symindex, i, mod);
+		}
+	}
+	return 0;
+}
+#endif
+