powerpc/book3e-64: Enable kexec

Allow KEXEC for book3e, and bypass or convert non-book3e stuff
in kexec code.

Signed-off-by: Tiejun Chen <[e-mail]>
[[e-mail]: move code to minimize diff, and cleanup]
Signed-off-by: Scott Wood <[e-mail]>

arch/powerpc/Kconfig

···
 
 config KEXEC
 	bool "kexec system call"
-	depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP))
+	depends on (PPC_BOOK3S || FSL_BOOKE || (44x && !SMP)) || PPC_BOOK3E
 	select KEXEC_CORE
 	help
 	  kexec is a system call that implements the ability to shutdown your

arch/powerpc/kernel/machine_kexec_64.c

···
 #include <asm/smp.h>
 #include <asm/hw_breakpoint.h>
 
+#ifdef CONFIG_PPC_BOOK3E
+int default_machine_kexec_prepare(struct kimage *image)
+{
+	int i;
+	/*
+	 * Since we use the kernel fault handlers and paging code to
+	 * handle the virtual mode, we must make sure no destination
+	 * overlaps kernel static data or bss.
+	 */
+	for (i = 0; i < image->nr_segments; i++)
+		if (image->segment[i].mem < __pa(_end))
+			return -ETXTBSY;
+	return 0;
+}
+#else
 int default_machine_kexec_prepare(struct kimage *image)
 {
 	int i;
···
 
 	return 0;
 }
+#endif /* !CONFIG_PPC_BOOK3E */
 
 static void copy_segments(unsigned long ind)
 {
···
 	/* NOTREACHED */
 }
 
+#ifndef CONFIG_PPC_BOOK3E
 /* Values we need to export to the second kernel via the device tree. */
 static unsigned long htab_base;
 static unsigned long htab_size;
···
 	return 0;
 }
 late_initcall(export_htab_values);
+#endif /* !CONFIG_PPC_BOOK3E */

arch/powerpc/kernel/misc_64.S

···
 	lhz	r25,PACAHWCPUID(r13)	/* get our phys cpu from paca */
 
 	/* disable interrupts, we are overwriting kernel data next */
+#ifdef CONFIG_PPC_BOOK3E
+	wrteei	0
+#else
 	mfmsr	r3
 	rlwinm	r3,r3,0,17,15
 	mtmsrd	r3,1
+#endif
 
 	/* copy dest pages, flush whole dest image */
 	mr	r3,r29
···
 	li	r6,1
 	stw	r6,kexec_flag-1b(5)
 
+#ifndef CONFIG_PPC_BOOK3E
 	/* clear out hardware hash page table and tlb */
 #if !defined(_CALL_ELF) || _CALL_ELF != 2
 	ld	r12,0(r27)		/* deref function descriptor */
···
 #endif
 	mtctr	r12
 	bctrl				/* ppc_md.hpte_clear_all(void); */
+#endif /* !CONFIG_PPC_BOOK3E */
 
 /*
  *   kexec image calling is: