Untested DTB support

tangrs · Apr 5, 2013 · be0595b · be0595b
1 parent dd742a8
commit be0595b
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Showing 10 changed files with 58 additions and 21 deletions.
diff --git a/atag.c b/atag.c
@@ -114,7 +114,7 @@ static void* atag_begin(void *head) {
 }
 
 #define ATAG(...) do { \
-        if (current > (char*)settings.atag.start + settings.atag.size) { \
+        if (current > (char*)settings.boot_param.start + settings.boot_param.size) { \
             printl("Internal error. ATAG buffer overrun" NEWLINE); \
             return -1; \
         } \
@@ -123,11 +123,11 @@ static void* atag_begin(void *head) {
 
 int atag_build() {
     char *current;
-    if (!settings.atag.start) {
-        printl("Internal error. settings.atag.start = NULL" NEWLINE);
+    if (!settings.boot_param.start) {
+        printl("Internal error. settings.boot_param.start = NULL" NEWLINE);
         return -1;
     }
-    current = atag_begin(settings.atag.start);
+    current = atag_begin(settings.boot_param.start);
     /*
         Begin building list of ATAGs
     */

diff --git a/cmd.c b/cmd.c
@@ -76,6 +76,7 @@ int process_cmd(char * cmd) {
     */
     DEFINE_COMMAND(kernel, load_kernel);
     DEFINE_COMMAND(initrd, load_ramdisk);
+    DEFINE_COMMAND(dtb, load_dtb);
     DEFINE_COMMAND(dump, dump_settings);
     DEFINE_COMMAND(free, show_mem);
     DEFINE_COMMAND(mach, setget_mach);

diff --git a/common.c b/common.c
@@ -94,8 +94,8 @@ void dump_settings(char * ignored __attribute__((unused))) {
     FOOTER_LEVEL0();
 
     HEADER_LEVEL0(atag);
-        DUMP_LEVEL1(settings.atag, start);
-        DUMP_LEVEL1(settings.atag, size);
+        DUMP_LEVEL1(settings.boot_param, start);
+        DUMP_LEVEL1(settings.boot_param, size);
     FOOTER_LEVEL0();
 
     HEADER_LEVEL0(mem_block);

diff --git a/common.h b/common.h
@@ -21,6 +21,7 @@
 #include <stddef.h>
 
 #define PAGE_SIZE 0x1000
+#define DTB_MACH_ID 3503
 
 struct params {
     struct {
@@ -34,9 +35,9 @@ struct params {
     } ramdisk;
 
     struct {
-        void* start;        /* A separate section of memory for writing ATAGs */
+        void* start;        /* A separate section of memory for writing ATAG and DTBs */
         size_t size;
-    } atag;
+    } boot_param;
 
     struct {
         void* start;        /* Memory block for kernel and ramdisk */
@@ -58,6 +59,7 @@ struct params {
 
     unsigned ramdisk_loaded:1;
     unsigned kernel_loaded:1;
+    unsigned dtb_loaded:1;
 };
 
 extern struct params settings;
@@ -70,4 +72,4 @@ void setget_rdisksize(char * arg);
 void poke(char *arg);
 void peek(char *arg);
 
-#endif
+#endif
diff --git a/kernel.c b/kernel.c
@@ -39,7 +39,9 @@ void kernel_boot(char * ignored __attribute__((unused))) {
 
     /* Kernels and ramdisks should already be loaded to their correct places */
     /* Build atag next */
-    if (atag_build()) return;
+    if (!settings.dtb_loaded) {
+       if (atag_build()) return;
+    }
 
     clear_cache();
     /* Disable D-Cache and MMU */
@@ -48,6 +50,6 @@ void kernel_boot(char * ignored __attribute__((unused))) {
                  "mcr p15, 0, r0, c1, c0,0 \n"
                  : : : "r0" );
     /* Bye bye */
-    entry(0, settings.machine_id, settings.atag.start);
+    entry(0, settings.machine_id, settings.boot_param.start);
     __builtin_unreachable();
 }
diff --git a/load.c b/load.c
@@ -107,3 +107,30 @@ void load_ramdisk(const char *filename) {
     printl("Ramdisk successfully loaded" NEWLINE);
     return;
 }
+
+void load_dtb(const char *filename) {
+    FILE* f;
+    size_t dtb_size = file_size(filename);
+
+    if (dtb_size > settings.boot_param.size) {
+        printl("DTB image too large!" NEWLINE);
+        return;
+    }
+
+    f = fopen(filename, "rb");
+    if (!f) {
+        printl("Failed to open dtb image %s" NEWLINE, filename);
+        return;
+    }
+
+    if (fread(settings.boot_param.start, 1, dtb_size, f) != dtb_size)
+        printl("Warning: read less data from file than expected" NEWLINE);
+
+    fclose(f);
+
+    settings.dtb_loaded = 1;
+    settings.machine_id = DTB_MACH_ID;
+
+    printl("DTB successfully loaded" NEWLINE);
+    return;
+}
diff --git a/load.h b/load.h
@@ -21,5 +21,6 @@
 
 void load_kernel(const char *filename);
 void load_ramdisk(const char *filename);
+void load_dtb(const char *filename);
 
-#endif
+#endif
diff --git a/mach.c b/mach.c
@@ -88,7 +88,10 @@ int detect_machine() {
             settings.machine_id = 4443;
             break;
         default:
-            printl("No machine ID for this platform" NEWLINE);
+            printl( "No machine ID for this platform." NEWLINE
+                    "Defaulting to DTB machine number %d." NEWLINE,
+                    DTB_MACH_ID);
+            settings.machine_id = DTB_MACH_ID;
             return -1;
     }
     return 0;

diff --git a/memory.c b/memory.c
@@ -76,13 +76,13 @@ void show_mem(char *ignored __attribute__((unused))) {
 #undef HUMAN
 
 void free_memory() {
-    free(settings.atag.start);
+    free(settings.boot_param.start);
     free(settings.mem_block.start);
 
-    settings.atag.start = NULL;
+    settings.boot_param.start = NULL;
     settings.mem_block.start = NULL;
 
-    settings.atag.size = 0;
+    settings.boot_param.size = 0;
     settings.mem_block.size = 0;
 
     settings.kernel.size = 0;
@@ -98,14 +98,15 @@ void free_memory() {
 void alloc_memory() {
     free_memory();
 
-    settings.atag.start = malloc(MAX_ATAG_SIZE);
-    if (settings.atag.start) settings.atag.size = MAX_ATAG_SIZE;
+    settings.boot_param.start = malloc(MAX_BOOT_PARAM_SIZE);
+    if (settings.boot_param.start)
+        settings.boot_param.size = MAX_BOOT_PARAM_SIZE;
 
     /* Allocate as much remaining memory as possible */
     settings.mem_block.start = max_malloc(&settings.mem_block.size);
 
     printl( "Allocated memory:" NEWLINE
             "   ATAGs:                 %u bytes" NEWLINE
             "   Kernel and ramdisk:    %u bytes" NEWLINE,
-            settings.atag.size, settings.mem_block.size);
+            settings.boot_param.size, settings.mem_block.size);
 }
diff --git a/memory.h b/memory.h
@@ -22,7 +22,7 @@
 
 #include "common.h"
 
-#define MAX_ATAG_SIZE           (0x8000-0x100)
+#define MAX_BOOT_PARAM_SIZE (0x4000-0x100)
 
 #define mem_block_size_free() (settings.mem_block.size - settings.kernel.size - settings.ramdisk.size)
 
@@ -31,4 +31,4 @@ void alloc_memory();
 void free_memory();
 void show_mem(char*);
 
-#endif
+#endif