powerpc/powernv: Remove OPAL v1 takeover

In commit 27f4488872d9 "Add OPAL takeover from PowerVM" we added support
for "takeover" on OPAL v1 machines.

This was a mode of operation where we would boot under pHyp, and query
for the presence of OPAL. If detected we would then do a special
sequence to take over the machine, and the kernel would end up running
in hypervisor mode.

OPAL v1 was never a supported product, and was never shipped outside
IBM. As far as we know no one is still using it.

Newer versions of OPAL do not use the takeover mechanism. Although the
query for OPAL should be harmless on machines with newer OPAL, we have
seen a machine where it causes a crash in Open Firmware.

The code in early_init_devtree() to copy boot_command_line into cmd_line
was added in commit 817c21ad9a1f "Get kernel command line accross OPAL
takeover", and AFAIK is only used by takeover, so should also be
removed.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 1 insertions, 141 deletions

diff --git a/arch/powerpc/platforms/powernv/Makefile b/arch/powerpc/platforms/powernv/Makefile
index d55891f..4ad227d 100644
--- a/arch/powerpc/platforms/powernv/Makefile
+++ b/arch/powerpc/platforms/powernv/Makefile
@@ -1,4 +1,4 @@
-obj-y			+= setup.o opal-takeover.o opal-wrappers.o opal.o opal-async.o
+obj-y			+= setup.o opal-wrappers.o opal.o opal-async.o
 obj-y			+= opal-rtc.o opal-nvram.o opal-lpc.o opal-flash.o
 obj-y			+= rng.o opal-elog.o opal-dump.o opal-sysparam.o opal-sensor.o
 obj-y			+= opal-msglog.o
diff --git a/arch/powerpc/platforms/powernv/opal-takeover.S b/arch/powerpc/platforms/powernv/opal-takeover.S
deleted file mode 100644
index 11a3169..0000000
--- a/arch/powerpc/platforms/powernv/opal-takeover.S
+++ /dev/null
@@ -1,140 +0,0 @@
-/*
- * PowerNV OPAL takeover assembly code, for use by prom_init.c
- *
- * Copyright 2011 IBM Corp.
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version
- * 2 of the License, or (at your option) any later version.
- */
-
-#include <asm/ppc_asm.h>
-#include <asm/hvcall.h>
-#include <asm/asm-offsets.h>
-#include <asm/opal.h>
-
-#define H_HAL_TAKEOVER			0x5124
-#define H_HAL_TAKEOVER_QUERY_MAGIC	-1
-
-	.text
-_GLOBAL(opal_query_takeover)
-	mfcr	r0
-	stw	r0,8(r1)
-	stdu	r1,-STACKFRAMESIZE(r1)
-	std	r3,STK_PARAM(R3)(r1)
-	std	r4,STK_PARAM(R4)(r1)
-	li	r3,H_HAL_TAKEOVER
-	li	r4,H_HAL_TAKEOVER_QUERY_MAGIC
-	HVSC
-	addi	r1,r1,STACKFRAMESIZE
-	ld	r10,STK_PARAM(R3)(r1)
-	std	r4,0(r10)
-	ld	r10,STK_PARAM(R4)(r1)
-	std	r5,0(r10)
-	lwz	r0,8(r1)
-	mtcrf	0xff,r0
-	blr
-
-_GLOBAL(opal_do_takeover)
-	mfcr	r0
-	stw	r0,8(r1)
-	mflr	r0
-	std	r0,16(r1)
-	bl	__opal_do_takeover
-	ld	r0,16(r1)
-	mtlr	r0
-	lwz	r0,8(r1)
-	mtcrf	0xff,r0
-	blr
-
-__opal_do_takeover:
-	ld	r4,0(r3)
-	ld	r5,0x8(r3)
-	ld	r6,0x10(r3)
-	ld	r7,0x18(r3)
-	ld	r8,0x20(r3)
-	ld	r9,0x28(r3)
-	ld	r10,0x30(r3)
-	ld	r11,0x38(r3)
-	li	r3,H_HAL_TAKEOVER
-	HVSC
-	blr
-
-	.globl opal_secondary_entry
-opal_secondary_entry:
-	mr	r31,r3
-	mfmsr	r11
-	li	r12,(MSR_SF | MSR_ISF)@highest
-	sldi	r12,r12,48
-	or	r11,r11,r12
-	mtmsrd	r11
-	isync
-	mfspr	r4,SPRN_PIR
-	std	r4,0(r3)
-1:	HMT_LOW
-	ld	r4,8(r3)
-	cmpli	cr0,r4,0
-	beq	1b
-	HMT_MEDIUM
-1:	addi	r3,r31,16
-	bl	__opal_do_takeover
-	b	1b
-
-_GLOBAL(opal_enter_rtas)
-	mflr	r0
-	std	r0,16(r1)
-        stdu	r1,-PROM_FRAME_SIZE(r1)	/* Save SP and create stack space */
-
-	/* Because PROM is running in 32b mode, it clobbers the high order half
-	 * of all registers that it saves.  We therefore save those registers
-	 * PROM might touch to the stack.  (r0, r3-r13 are caller saved)
-	*/
-	SAVE_GPR(2, r1)
-	SAVE_GPR(13, r1)
-	SAVE_8GPRS(14, r1)
-	SAVE_10GPRS(22, r1)
-	mfcr	r10
-	mfmsr	r11
-	std	r10,_CCR(r1)
-	std	r11,_MSR(r1)
-
-	/* Get the PROM entrypoint */
-	mtlr	r5
-
-	/* Switch MSR to 32 bits mode
-	 */
-        li      r12,1
-        rldicr  r12,r12,MSR_SF_LG,(63-MSR_SF_LG)
-        andc    r11,r11,r12
-        li      r12,1
-        rldicr  r12,r12,MSR_ISF_LG,(63-MSR_ISF_LG)
-        andc    r11,r11,r12
-        mtmsrd  r11
-        isync
-
-	/* Enter RTAS here... */
-	blrl
-
-	/* Just make sure that r1 top 32 bits didn't get
-	 * corrupt by OF
-	 */
-	rldicl	r1,r1,0,32
-
-	/* Restore the MSR (back to 64 bits) */
-	ld	r0,_MSR(r1)
-	MTMSRD(r0)
-        isync
-
-	/* Restore other registers */
-	REST_GPR(2, r1)
-	REST_GPR(13, r1)
-	REST_8GPRS(14, r1)
-	REST_10GPRS(22, r1)
-	ld	r4,_CCR(r1)
-	mtcr	r4
-
-        addi	r1,r1,PROM_FRAME_SIZE
-	ld	r0,16(r1)
-	mtlr    r0
-	blr