summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--common/module.c65
-rw-r--r--include/asm-generic/u-boot.lds.h2
-rw-r--r--include/module.h28
3 files changed, 91 insertions, 4 deletions
diff --git a/common/module.c b/common/module.c
index 65f0ad0..0985567 100644
--- a/common/module.c
+++ b/common/module.c
@@ -16,6 +16,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#define DEBUG
#include <common.h>
#include <errno.h>
@@ -27,15 +28,54 @@
#include <fs.h>
#include <kallsyms.h>
+static unsigned int find_sec(Elf_Ehdr *hdr,
+ Elf_Shdr *sechdrs,
+ const char *secstrings,
+ const char *name, int nlen)
+{
+ unsigned int i;
+
+ for (i = 1; i < hdr->e_shnum; i++)
+ /* Alloc bit cleared means "ignore it." */
+ if ((sechdrs[i].sh_flags & SHF_ALLOC)) {
+ if (nlen && !strncmp(secstrings+sechdrs[i].sh_name, name, nlen))
+ return i;
+ if (!nlen && !strcmp(secstrings+sechdrs[i].sh_name, name))
+ return i;
+ }
+ return 0;
+}
+
+/* Provided by the linker */
+extern const struct kernel_symbol __u_boot_symtab_start[];
+extern const struct kernel_symbol __u_boot_symtab_end[];
+
+/* lookup symbol in given range of kernel_symbols */
+static const struct kernel_symbol *lookup_symbol(const char *name,
+ const struct kernel_symbol *start,
+ const struct kernel_symbol *stop)
+{
+ const struct kernel_symbol *ks = start;
+ for (; ks < stop; ks++) {
+ printf("name: %s\n", ks->name);
+ if (strcmp(ks->name, name) == 0)
+ return ks;
+ }
+ return NULL;
+}
+
static unsigned long resolve_symbol(Elf32_Shdr *sechdrs,
const char *name)
{
- unsigned long ret;
+ const struct kernel_symbol *ks;
debug("%s: %s\n", __FUNCTION__, name);
- ret = kallsyms_lookup_name(name);
+ ks = lookup_symbol(name, __u_boot_symtab_start,
+ __u_boot_symtab_end);
- return ret;
+ if (ks)
+ return ks->value;
+ return 0;
}
/* Change all symbols so that sh_value encodes the pointer directly. */
@@ -157,6 +197,7 @@ struct module * load_module(void *mod_image, unsigned long len)
char *secstrings;
void *ptr = NULL;
int err;
+ int cmdindex;
if (len < sizeof(*ehdr))
return NULL;
@@ -243,6 +284,22 @@ struct module * load_module(void *mod_image, unsigned long len)
numsyms = sechdrs[symindex].sh_size / sizeof(Elf32_Sym);
sym = (void *)sechdrs[symindex].sh_addr;
+ /*
+ * FIXME: in .o files we have the command structs in the
+ * .u_boot_cmd_<name> section to be able to let the linker
+ * sort the commands alphabetically. When using the .o files
+ * as modules this is bad because we have the commands in different
+ * sections. So we probably need a linking stage for modules to
+ * put the different sections back into a single one.
+ *
+ * For now we only find the _first_ command in a module.
+ */
+ cmdindex = find_sec(ehdr, sechdrs, secstrings,
+ MODULE_SYMBOL_PREFIX ".u_boot_cmd_", 12);
+ if (cmdindex) {
+ register_command((void *)sechdrs[cmdindex].sh_addr);
+ }
+
for (i = 0; i < numsyms; i++) {
if (!strcmp(strtab + sym[i].st_name, MODULE_SYMBOL_PREFIX "init_module")) {
printf("found init_module() at 0x%08x\n", sym[i].st_value);
@@ -274,7 +331,7 @@ static int do_insmod (cmd_tbl_t *cmdtp, int argc, char *argv[])
buf = read_file(argv[1], &len);
if (!buf) {
- printf("error\n");
+ perror("insmod");
return 1;
}
diff --git a/include/asm-generic/u-boot.lds.h b/include/asm-generic/u-boot.lds.h
index e8e9ce1..f01fc84 100644
--- a/include/asm-generic/u-boot.lds.h
+++ b/include/asm-generic/u-boot.lds.h
@@ -10,3 +10,5 @@
*(.initcall.7)
#define U_BOOT_CMDS *(SORT_BY_NAME(.u_boot_cmd*))
+
+#define U_BOOT_SYMS *(__u_boot_symtab)
diff --git a/include/module.h b/include/module.h
index faea2ae..421b937 100644
--- a/include/module.h
+++ b/include/module.h
@@ -4,6 +4,34 @@
#include <elf.h>
#include <asm/module.h>
+#ifndef MODULE_SYMBOL_PREFIX
+#define MODULE_SYMBOL_PREFIX
+#endif
+
+#ifdef CONFIG_MODULE
+struct kernel_symbol
+{
+ unsigned long value;
+ const char *name;
+};
+
+/* For every exported symbol, place a struct in the __ksymtab section */
+#define __EXPORT_SYMBOL(sym, sec) \
+ extern typeof(sym) sym; \
+ static const char __u_boot_strtab_##sym[] \
+ __attribute__((section("__u_boot_symtab_strings"))) \
+ = MODULE_SYMBOL_PREFIX #sym; \
+ static const struct kernel_symbol __u_boot_symtab_##sym \
+ __used \
+ __attribute__((section("__u_boot_symtab" sec), unused)) \
+ = { (unsigned long)&sym, __u_boot_strtab_##sym }
+
+#define EXPORT_SYMBOL(sym) \
+ __EXPORT_SYMBOL(sym, "")
+#else
+#define EXPORT_SYMBOL(sym)
+#endif
+
struct module {
char *name;