linux/arch/powerpc/kernel/cpu_setup_ppc970.S
Paul Mackerras 969391c58a powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and architecture bits
This replaces the single CPU_FTR_HVMODE_206 bit with two bits, one to
indicate that we have a usable hypervisor mode, and another to indicate
that the processor conforms to PowerISA version 2.06.  We also add
another bit to indicate that the processor conforms to ISA version 2.01
and set that for PPC970 and derivatives.

Some PPC970 chips (specifically those in Apple machines) have a
hypervisor mode in that MSR[HV] is always 1, but the hypervisor mode
is not useful in the sense that there is no way to run any code in
supervisor mode (HV=0 PR=0).  On these processors, the LPES0 and LPES1
bits in HID4 are always 0, and we use that as a way of detecting that
hypervisor mode is not useful.

Where we have a feature section in assembly code around code that
only applies on POWER7 in hypervisor mode, we use a construct like

END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

The definition of END_FTR_SECTION_IFSET is such that the code will
be enabled (not overwritten with nops) only if all bits in the
provided mask are set.

Note that the CPU feature check in __tlbie() only needs to check the
ARCH_206 bit, not the HVMODE bit, because __tlbie() can only get called
if we are running bare-metal, i.e. in hypervisor mode.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
2011-07-12 13:16:58 +03:00

211 lines
4.1 KiB
ArmAsm

/*
* This file contains low level CPU setup functions.
* Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
*
* 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/processor.h>
#include <asm/page.h>
#include <asm/cputable.h>
#include <asm/ppc_asm.h>
#include <asm/asm-offsets.h>
#include <asm/cache.h>
_GLOBAL(__cpu_preinit_ppc970)
/* Do nothing if not running in HV mode */
mfmsr r0
rldicl. r0,r0,4,63
beqlr
/* Make sure HID4:rm_ci is off before MMU is turned off, that large
* pages are enabled with HID4:61 and clear HID5:DCBZ_size and
* HID5:DCBZ32_ill
*/
li r0,0
mfspr r3,SPRN_HID4
rldimi r3,r0,40,23 /* clear bit 23 (rm_ci) */
rldimi r3,r0,2,61 /* clear bit 61 (lg_pg_en) */
sync
mtspr SPRN_HID4,r3
isync
sync
mfspr r3,SPRN_HID5
rldimi r3,r0,6,56 /* clear bits 56 & 57 (DCBZ*) */
sync
mtspr SPRN_HID5,r3
isync
sync
/* Setup some basic HID1 features */
mfspr r0,SPRN_HID1
li r3,0x1200 /* enable i-fetch cacheability */
sldi r3,r3,44 /* and prefetch */
or r0,r0,r3
mtspr SPRN_HID1,r0
mtspr SPRN_HID1,r0
isync
/* Clear HIOR */
li r0,0
sync
mtspr SPRN_HIOR,0 /* Clear interrupt prefix */
isync
blr
/* Definitions for the table use to save CPU states */
#define CS_HID0 0
#define CS_HID1 8
#define CS_HID4 16
#define CS_HID5 24
#define CS_SIZE 32
.data
.balign L1_CACHE_BYTES,0
cpu_state_storage:
.space CS_SIZE
.balign L1_CACHE_BYTES,0
.text
_GLOBAL(__setup_cpu_ppc970)
/* Do nothing if not running in HV mode */
mfmsr r0
rldicl. r0,r0,4,63
beq no_hv_mode
mfspr r0,SPRN_HID0
li r11,5 /* clear DOZE and SLEEP */
rldimi r0,r11,52,8 /* set NAP and DPM */
li r11,0
rldimi r0,r11,32,31 /* clear EN_ATTN */
b load_hids /* Jump to shared code */
_GLOBAL(__setup_cpu_ppc970MP)
/* Do nothing if not running in HV mode */
mfmsr r0
rldicl. r0,r0,4,63
beq no_hv_mode
mfspr r0,SPRN_HID0
li r11,0x15 /* clear DOZE and SLEEP */
rldimi r0,r11,52,6 /* set DEEPNAP, NAP and DPM */
li r11,0
rldimi r0,r11,32,31 /* clear EN_ATTN */
load_hids:
mtspr SPRN_HID0,r0
mfspr r0,SPRN_HID0
mfspr r0,SPRN_HID0
mfspr r0,SPRN_HID0
mfspr r0,SPRN_HID0
mfspr r0,SPRN_HID0
mfspr r0,SPRN_HID0
sync
isync
/* Try to set LPES = 01 in HID4 */
mfspr r0,SPRN_HID4
clrldi r0,r0,1 /* clear LPES0 */
ori r0,r0,HID4_LPES1 /* set LPES1 */
sync
mtspr SPRN_HID4,r0
isync
/* Save away cpu state */
LOAD_REG_ADDR(r5,cpu_state_storage)
/* Save HID0,1,4 and 5 */
mfspr r3,SPRN_HID0
std r3,CS_HID0(r5)
mfspr r3,SPRN_HID1
std r3,CS_HID1(r5)
mfspr r4,SPRN_HID4
std r4,CS_HID4(r5)
mfspr r3,SPRN_HID5
std r3,CS_HID5(r5)
/* See if we successfully set LPES1 to 1; if not we are in Apple mode */
andi. r4,r4,HID4_LPES1
bnelr
no_hv_mode:
/* Disable CPU_FTR_HVMODE and exit, since we don't have HV mode */
ld r5,CPU_SPEC_FEATURES(r4)
LOAD_REG_IMMEDIATE(r6,CPU_FTR_HVMODE)
andc r5,r5,r6
std r5,CPU_SPEC_FEATURES(r4)
blr
/* Called with no MMU context (typically MSR:IR/DR off) to
* restore CPU state as backed up by the previous
* function. This does not include cache setting
*/
_GLOBAL(__restore_cpu_ppc970)
/* Do nothing if not running in HV mode */
mfmsr r0
rldicl. r0,r0,4,63
beqlr
LOAD_REG_ADDR(r5,cpu_state_storage)
/* Before accessing memory, we make sure rm_ci is clear */
li r0,0
mfspr r3,SPRN_HID4
rldimi r3,r0,40,23 /* clear bit 23 (rm_ci) */
sync
mtspr SPRN_HID4,r3
isync
sync
/* Clear interrupt prefix */
li r0,0
sync
mtspr SPRN_HIOR,0
isync
/* Restore HID0 */
ld r3,CS_HID0(r5)
sync
isync
mtspr SPRN_HID0,r3
mfspr r3,SPRN_HID0
mfspr r3,SPRN_HID0
mfspr r3,SPRN_HID0
mfspr r3,SPRN_HID0
mfspr r3,SPRN_HID0
mfspr r3,SPRN_HID0
sync
isync
/* Restore HID1 */
ld r3,CS_HID1(r5)
sync
isync
mtspr SPRN_HID1,r3
mtspr SPRN_HID1,r3
sync
isync
/* Restore HID4 */
ld r3,CS_HID4(r5)
sync
isync
mtspr SPRN_HID4,r3
sync
isync
/* Restore HID5 */
ld r3,CS_HID5(r5)
sync
isync
mtspr SPRN_HID5,r3
sync
isync
blr