svn commit: r276687 - user/nwhitehorn/kboot/powerpc/kboot

[Nathan Whitehorn]

Author: nwhitehorn
Date: Mon Jan  5 04:30:21 2015
New Revision: 276687
URL: https://svnweb.freebsd.org/changeset/base/276687

Log:
  Finish TODOs. This boots a functioning kernel on PS3 -- and one that can
  print Hello World on POWER8.

Modified:
  user/nwhitehorn/kboot/powerpc/kboot/kerneltramp.S
  user/nwhitehorn/kboot/powerpc/kboot/ppc64_elf_freebsd.c

Modified: user/nwhitehorn/kboot/powerpc/kboot/kerneltramp.S
==============================================================================
--- user/nwhitehorn/kboot/powerpc/kboot/kerneltramp.S	Mon Jan  5 03:27:09 2015	(r276686)
+++ user/nwhitehorn/kboot/powerpc/kboot/kerneltramp.S	Mon Jan  5 04:30:21 2015	(r276687)
@@ -3,13 +3,12 @@
  *
  * The goal here is to call the actual kernel entry point with the arguments it
  * expects when kexec calls into it with no arguments. The value of the kernel
- * entry point and arguments r3-r7 are copied into the trampoline text (which can
- * be executed from any address) at bytes 8-32.
+ * entry point and arguments r3-r7 are copied into the trampoline text (which
+ * can be executed from any address) at bytes 8-32. kexec begins execution
+ * of APs at 0x60 bytes past the entry point, executing in a copy relocated
+ * to the absolute address 0x60. Here we implement a loop waiting on the release
+ * of a lock by the kernel at 0x40.
  * 
- * TODO:
- * - This may or may not need to relocate the kernel before executing it
- * - kexec enters at address 0x60 for all APs. We need to catch these and hold
- *   them.
  */
 
 #include <machine/asm.h>
@@ -17,9 +16,26 @@
         .globl  CNAME(kerneltramp),CNAME(szkerneltramp)
 CNAME(kerneltramp):
 	mflr %r9
-	bl 1f
+	bl 2f
 	.space 24	/* branch address, r3-r7 */
-1:
+
+. = kerneltramp + 0x40	/* AP spinlock */
+	.long 0
+
+. = kerneltramp + 0x60	/* AP entry point */
+	li	%r3,0x40
+1:	lwz	%r1,0(%r3)
+	cmpwi	%r1,0
+	beq	1b
+
+	/* Jump into CPU reset */
+	li	%r0,0x100
+	icbi	0,%r0
+	isync
+	sync
+	ba	0x100
+
+2:			/* Continuation of kerneltramp */
 	mflr	%r8
 	mtlr	%r9
 	lwz	%r3,0(%r8)
@@ -31,6 +47,7 @@ CNAME(kerneltramp):
 	lwz	%r6,16(%r8)
 	lwz	%r7,20(%r8)
 	bctr
+	
 endkerneltramp:
 
 	.data

Modified: user/nwhitehorn/kboot/powerpc/kboot/ppc64_elf_freebsd.c
==============================================================================
--- user/nwhitehorn/kboot/powerpc/kboot/ppc64_elf_freebsd.c	Mon Jan  5 03:27:09 2015	(r276686)
+++ user/nwhitehorn/kboot/powerpc/kboot/ppc64_elf_freebsd.c	Mon Jan  5 04:30:21 2015	(r276687)
@@ -68,7 +68,7 @@ ppc64_elf_exec(struct preloaded_file *fp
 	Elf_Ehdr		*e;
 	int			error;
 	uint32_t		*trampoline;
-	vm_offset_t		trampolinebase = 16*1024*1024; /* XXX */
+	vm_offset_t		trampolinebase = 96*1024*1024; /* XXX */
 
 	if ((fmp = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL) {
 		return(EFTYPE);