PERFORCE change 219948 for review

[Robert Watson]

http://p4web.freebsd.org/@@219948?ac=10

Change 219948 by rwatson at rwatson_zenith_cl_cam_ac_uk on 2013/01/04 09:09:35

	Add code so that the BERI boot process can ask the kernel linker for
	DTB blobs that may have been left for it by the boot loader, as done
	on PowerPC and ARM.  This will require both a more mature boot
	loader, and more mature boot loader argument passing mechanism,
	than currently supported on BERI.

Affected files ...

.. //depot/projects/ctsrd/beribsd/src/sys/mips/beri/beri_machdep.c#8 edit
.. //depot/projects/ctsrd/beribsd/src/sys/mips/include/metadata.h#2 edit

Differences ...

==== //depot/projects/ctsrd/beribsd/src/sys/mips/beri/beri_machdep.c#8 (text+ko) ====

@@ -45,6 +45,7 @@
 #include <sys/cpu.h>
 #include <sys/cons.h>
 #include <sys/exec.h>
+#include <sys/linker.h>
 #include <sys/ucontext.h>
 #include <sys/proc.h>
 #include <sys/kdb.h>
@@ -70,6 +71,7 @@
 #include <machine/cpuregs.h>
 #include <machine/hwfunc.h>
 #include <machine/md_var.h>
+#include <machine/metadata.h>
 #include <machine/pmap.h>
 #include <machine/trap.h>
 
@@ -135,6 +137,10 @@
 	char **argv = (char **)a1;
 	char **envp = (char **)a2;
 	unsigned int memsize = a3;
+#ifdef FDT
+	vm_offset_t dtbp;
+	void *kmdp;
+#endif
 	int i;
 
 	/* clear the BSS and SBSS segments */
@@ -146,8 +152,24 @@
 	mips_pcpu0_init();
 
 #ifdef FDT
-#ifndef FDT_DTB_STATIC
-#error	"mips_init with FDT requires FDT_DTB_STATIC"
+	/*
+	 * Find the dtb passed in by the boot loader (currently fictional).
+	 */
+	kmdp = preload_search_by_type("elf kernel");
+	if (kmdp != NULL)
+		dtbp = MD_FETCH(kmdp, MODINFOMD_DTBP, vm_offset_t);
+	else
+		dtbp = (vm_offset_t)NULL;
+
+#if defined(FDT_DTB_STATIC)
+	/*
+	 * In case the device tree blob was not retrieved (from metadata) try
+	 * to use the statically embedded one.
+	 */
+	if (dtbp == (vm_offset_t)NULL)
+		dtbp = (vm_offset_t)&fdt_static_dtb;
+#else
+#error	"Non-static FDT not yet supported on BERI"
 #endif
 
 	if (OF_install(OFW_FDT, 0) == FALSE)

==== //depot/projects/ctsrd/beribsd/src/sys/mips/include/metadata.h#2 (text+ko) ====

@@ -30,5 +30,6 @@
 #define	_MACHINE_METADATA_H_
 
 #define	MODINFOMD_SMAP		0x1001
+#define	MODINFOMD_DTBP	0x1002
 
 #endif /* !_MACHINE_METADATA_H_ */