FYI
Edson had to patch this in to get BDI to work on 85xx with 2.6.14.
--- /home/edson/linux-2.6.14/Makefile 2005-10-27 17:02:08.000000000 -0700
+++ Makefile 2005-11-02 10:32:00.000000000 -0800
@@ -524,7 +524,7 @@
endif
ifdef CONFIG_DEBUG_INFO
-CFLAGS += -g
+CFLAGS += -g -ggdb
endif
include $(srctree)/arch/$(ARCH)/Makefile
--- /home/edson/linux-2.6.14/arch/ppc/kernel/head_fsl_booke.S 2005-10-27
17:02:08.000000000 -0700
+++ arch/ppc/kernel/head_fsl_booke.S 2005-11-02 19:59:21.000000000 -0800
@@ -187,6 +187,10 @@
xori r6,r4,1
slwi r6,r6,5 /* setup new context with other address space */
+#if defined(CONFIG_BDI_SWITCH)
+ mfmsr r9
+ rlwimi r6,r9,0,22,22 /* preserve MSR[DE] */
+#endif
bl 1f /* Find our address */
1: mflr r9
rlwimi r7,r9,0,20,31
@@ -238,6 +242,10 @@
/* 7. Jump to KERNELBASE mapping */
lis r7,MSR_KERNEL at h
ori r7,r7,MSR_KERNEL at l
+#if defined(CONFIG_BDI_SWITCH)
+ mfmsr r9
+ rlwimi r7,r9,0,22,22 /* preserve MSR[DE] */
+#endif
bl 1f /* Find our address */
1: mflr r9
rlwimi r6,r9,0,20,31
@@ -371,6 +379,10 @@
ori r4,r4,start_kernel at l
lis r3,MSR_KERNEL at h
ori r3,r3,MSR_KERNEL at l
+#if defined(CONFIG_BDI_SWITCH)
+ mfmsr r5
+ rlwimi r3,r5,0,22,22 /* preserve MSR[DE] */
+#endif
mtspr SPRN_SRR0,r4
mtspr SPRN_SRR1,r3
rfi /* change context and jump to start_kernel */
--- /home/edson/linux-2.6.14/arch/ppc/kernel/process.c 2005-10-27
17:02:08.000000000 -0700
+++ arch/ppc/kernel/process.c 2005-11-02 19:33:12.000000000 -0800
@@ -473,6 +473,10 @@
regs->nip = nip;
regs->gpr[1] = sp;
regs->msr = MSR_USER;
+#if (defined(CONFIG_BOOKE) && defined(CONFIG_BDI_SWITCH))
+ /* propagate the debug enable bit for BDI support */
+ regs->msr |= (mfmsr() & MSR_DE);
+#endif
if (last_task_used_math == current)
last_task_used_math = NULL;
if (last_task_used_altivec == current)
