PowerNV: Put processor to power-save state in idle thread

When processor enters power-save state it releases resources shared with other
cpu threads which makes other cores working much faster.

This patch also implements saving and restoring registers that might get
corrupted in power-save state.

Submitted by:          Patryk Duda <pdk@semihalf.com>
Obtained from:         Semihalf
Reviewed by:           jhibbits, nwhitehorn, wma
Sponsored by:          IBM, QCM Technologies
Differential revision: https://reviews.freebsd.org/D14330
This commit is contained in:
Wojciech Macek 2018-02-21 14:28:40 +00:00
parent 70639f9a5e
commit 6d13fd638c
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=329712
9 changed files with 251 additions and 9 deletions

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@ -198,6 +198,7 @@ powerpc/powerpc/clock.c standard
powerpc/powerpc/copyinout.c standard
powerpc/powerpc/copystr.c standard
powerpc/powerpc/cpu.c standard
powerpc/powerpc/cpu_subr64.S optional powerpc64
powerpc/powerpc/db_disasm.c optional ddb
powerpc/powerpc/db_hwwatch.c optional ddb
powerpc/powerpc/db_interface.c optional ddb

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@ -53,6 +53,8 @@ GLOBAL(__startkernel)
.llong begin
GLOBAL(__endkernel)
.llong end
GLOBAL(can_wakeup)
.llong 0x0
.align 4
#define TMPSTKSZ 16384 /* 16K temporary stack */
@ -60,6 +62,7 @@ GLOBAL(tmpstk)
.space TMPSTKSZ
TOC_ENTRY(tmpstk)
TOC_ENTRY(can_wakeup)
/*
* Entry point for bootloaders that do not fully implement ELF and start
@ -96,6 +99,10 @@ ap_kexec_start: /* At 0x60 past start, copied to 0x60 by kexec */
/* Released */
or 2,2,2 /* unyield */
/* Make sure that it will be software reset. Clear SRR1 */
li %r1,0
mtsrr1 %r1
ba EXC_RST

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@ -398,8 +398,11 @@ cpudep_ap_setup()
case IBMPOWER8:
case IBMPOWER8E:
#ifdef __powerpc64__
if (mfmsr() & PSL_HV)
mtspr(SPR_LPCR, mfspr(SPR_LPCR) | LPCR_LPES);
if (mfmsr() & PSL_HV) {
mtspr(SPR_LPCR, mfspr(SPR_LPCR) | LPCR_LPES |
LPCR_PECE_WAKESET);
isync();
}
#endif
break;
default:

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@ -307,10 +307,24 @@ dtrace_invop_calltrap_addr:
* once the MMU is turned on.
*/
.globl CNAME(rstcode), CNAME(rstcodeend), CNAME(cpu_reset_handler)
.globl CNAME(cpu_wakeup_handler)
.p2align 3
CNAME(rstcode):
/*
* Check if this is software reset or
* processor is waking up from power saving mode
* It is software reset when 46:47 = 0b00
*/
mfsrr1 %r9 /* Load SRR1 into r9 */
andis. %r9,%r9,0x3 /* Logic AND with 46:47 bits */
beq 2f /* Branch if software reset */
bl 1f
.llong cpu_wakeup_handler
/* It is software reset */
/* Explicitly set MSR[SF] */
mfmsr %r9
2: mfmsr %r9
li %r8,1
insrdi %r9,%r8,1,0
mtmsrd %r9
@ -318,6 +332,7 @@ CNAME(rstcode):
bl 1f
.llong cpu_reset_handler /* Make sure to maintain 8-byte alignment */
1: mflr %r9
ld %r9,0(%r9)
mtlr %r9
@ -359,6 +374,59 @@ cpu_reset_handler:
9:
b 9b
cpu_wakeup_handler:
GET_TOCBASE(%r2)
/* Check for false wake up due to badly SRR1 set (eg. by OPAL) */
ld %r3,TOC_REF(can_wakeup)(%r2)
ld %r3,0(%r3)
cmpdi %r3,0
beq cpu_reset_handler
/* Turn on MMU after return from interrupt */
mfsrr1 %r3
ori %r3,%r3,(PSL_IR | PSL_DR)
mtsrr1 %r3
/* Turn on MMU (needed to access PCB) */
mfmsr %r3
ori %r3,%r3,(PSL_IR | PSL_DR)
mtmsr %r3
isync
mfsprg0 %r3
ld %r3,PC_CURTHREAD(%r3) /* Get current thread */
ld %r3,TD_PCB(%r3) /* Get PCB of current thread */
ld %r12,PCB_CONTEXT(%r3) /* Load the non-volatile GP regs. */
ld %r13,PCB_CONTEXT+1*8(%r3)
ld %r14,PCB_CONTEXT+2*8(%r3)
ld %r15,PCB_CONTEXT+3*8(%r3)
ld %r16,PCB_CONTEXT+4*8(%r3)
ld %r17,PCB_CONTEXT+5*8(%r3)
ld %r18,PCB_CONTEXT+6*8(%r3)
ld %r19,PCB_CONTEXT+7*8(%r3)
ld %r20,PCB_CONTEXT+8*8(%r3)
ld %r21,PCB_CONTEXT+9*8(%r3)
ld %r22,PCB_CONTEXT+10*8(%r3)
ld %r23,PCB_CONTEXT+11*8(%r3)
ld %r24,PCB_CONTEXT+12*8(%r3)
ld %r25,PCB_CONTEXT+13*8(%r3)
ld %r26,PCB_CONTEXT+14*8(%r3)
ld %r27,PCB_CONTEXT+15*8(%r3)
ld %r28,PCB_CONTEXT+16*8(%r3)
ld %r29,PCB_CONTEXT+17*8(%r3)
ld %r30,PCB_CONTEXT+18*8(%r3)
ld %r31,PCB_CONTEXT+19*8(%r3)
ld %r5,PCB_CR(%r3) /* Load the condition register */
mtcr %r5
ld %r5,PCB_LR(%r3) /* Load the link register */
mtsrr0 %r5
ld %r1,PCB_SP(%r3) /* Load the stack pointer */
ld %r2,PCB_TOC(%r3) /* Load the TOC pointer */
rfid
/*
* This code gets copied to all the trap vectors
* (except ISI/DSI, ALI, and the interrupts). Has to fit in 8 instructions!

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@ -112,6 +112,11 @@ get_cyclecount(void)
extern char btext[];
extern char etext[];
#ifdef __powerpc64__
extern void enter_idle_powerx(void);
extern uint64_t can_wakeup;
#endif
void cpu_halt(void);
void cpu_reset(void);
void cpu_sleep(void);

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@ -201,7 +201,14 @@
#define SPR_LPCR 0x13e /* Logical Partitioning Control */
#define LPCR_LPES 0x008 /* Bit 60 */
#define LPCR_PECE_DRBL (1ULL << 16) /* Directed Privileged Doorbell */
#define LPCR_PECE_HDRBL (1ULL << 15) /* Directed Hypervisor Doorbell */
#define LPCR_PECE_EXT (1ULL << 14) /* External exceptions */
#define LPCR_PECE_DECR (1ULL << 13) /* Decrementer exceptions */
#define LPCR_PECE_ME (1ULL << 12) /* Machine Check and Hypervisor */
/* Maintenance exceptions */
#define LPCR_PECE_WAKESET (LPCR_PECE_EXT | LPCR_PECE_DECR | LPCR_PECE_ME)
#define SPR_EPCR 0x133
#define EPCR_EXTGS 0x80000000
#define EPCR_DTLBGS 0x40000000

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@ -139,7 +139,9 @@ powernv_attach(platform_t plat)
opal_call(OPAL_REINIT_CPUS, 1 /* Big endian */);
#endif
cpu_idle_hook = powernv_cpu_idle;
if (cpu_idle_hook == NULL)
cpu_idle_hook = powernv_cpu_idle;
powernv_boot_pir = mfspr(SPR_PIR);
/* LPID must not be altered when PSL_DR or PSL_IR is set */
@ -150,11 +152,11 @@ powernv_attach(platform_t plat)
mtspr(SPR_LPID, 0);
isync();
mtmsr(msr);
mtspr(SPR_LPCR, LPCR_LPES);
isync();
mtmsr(msr);
/* Init CPU bits */
powernv_smp_ap_init(plat);

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@ -68,6 +68,8 @@
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/sysctl.h>
#include <sys/sched.h>
#include <sys/smp.h>
#include <machine/bus.h>
#include <machine/cpu.h>
@ -81,11 +83,15 @@
static void cpu_6xx_setup(int cpuid, uint16_t vers);
static void cpu_970_setup(int cpuid, uint16_t vers);
static void cpu_booke_setup(int cpuid, uint16_t vers);
static void cpu_powerx_setup(int cpuid, uint16_t vers);
int powerpc_pow_enabled;
void (*cpu_idle_hook)(sbintime_t) = NULL;
static void cpu_idle_60x(sbintime_t);
static void cpu_idle_booke(sbintime_t);
#ifdef __powerpc64__
static void cpu_idle_powerx(sbintime_t);
#endif
struct cputab {
const char *name;
@ -156,13 +162,13 @@ static const struct cputab models[] = {
PPC_FEATURE_SMT | PPC_FEATURE_ARCH_2_05 | PPC_FEATURE_ARCH_2_06 |
PPC_FEATURE_HAS_VSX,
PPC_FEATURE2_ARCH_2_07 | PPC_FEATURE2_HAS_HTM | PPC_FEATURE2_ISEL |
PPC_FEATURE2_HAS_VCRYPTO, NULL },
PPC_FEATURE2_HAS_VCRYPTO, cpu_powerx_setup },
{ "IBM POWER8", IBMPOWER8, REVFMT_MAJMIN,
PPC_FEATURE_64 | PPC_FEATURE_HAS_ALTIVEC | PPC_FEATURE_HAS_FPU |
PPC_FEATURE_SMT | PPC_FEATURE_ARCH_2_05 | PPC_FEATURE_ARCH_2_06 |
PPC_FEATURE_HAS_VSX,
PPC_FEATURE2_ARCH_2_07 | PPC_FEATURE2_HAS_HTM | PPC_FEATURE2_ISEL |
PPC_FEATURE2_HAS_VCRYPTO, NULL },
PPC_FEATURE2_HAS_VCRYPTO, cpu_powerx_setup },
{ "IBM POWER9", IBMPOWER9, REVFMT_MAJMIN,
PPC_FEATURE_64 | PPC_FEATURE_HAS_ALTIVEC | PPC_FEATURE_HAS_FPU |
PPC_FEATURE_SMT | PPC_FEATURE_ARCH_2_05 | PPC_FEATURE_ARCH_2_06 |
@ -610,6 +616,29 @@ cpu_970_setup(int cpuid, uint16_t vers)
cpu_idle_hook = cpu_idle_60x;
}
static void
cpu_powerx_setup(int cpuid, uint16_t vers)
{
#ifdef __powerpc64__
if ((mfmsr() & PSL_HV) == 0)
return;
/* Configure power-saving */
switch (vers) {
case IBMPOWER8:
case IBMPOWER8E:
mtspr(SPR_LPCR, mfspr(SPR_LPCR) | LPCR_PECE_WAKESET);
isync();
break;
default:
return;
}
cpu_idle_hook = cpu_idle_powerx;
#endif
}
static int
cpu_feature_bit(SYSCTL_HANDLER_ARGS)
{
@ -696,3 +725,26 @@ cpu_idle_booke(sbintime_t sbt)
#endif
}
#ifdef __powerpc64__
static void
cpu_idle_powerx(sbintime_t sbt)
{
/* Sleeping when running on one cpu gives no advantages - avoid it */
if (smp_started == 0)
return;
spinlock_enter();
if (sched_runnable()) {
spinlock_exit();
return;
}
if (can_wakeup == 0)
can_wakeup = 1;
mb();
enter_idle_powerx();
spinlock_exit();
}
#endif

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@ -0,0 +1,97 @@
/*-
* Copyright (c) 2017-2018 QCM Technologies.
* Copyright (c) 2017-2018 Semihalf.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include "assym.s"
#include <machine/asm.h>
.globl CNAME(power_save_sequence)
.p2align 3
ENTRY(enter_idle_powerx)
mfsprg0 %r3 /* Get the pcpu pointer */
ld %r3,PC_CURTHREAD(%r3) /* Get current thread */
ld %r3,TD_PCB(%r3) /* Get PCB of current thread */
std %r12,PCB_CONTEXT(%r3) /* Save the non-volatile GP regs. */
std %r13,PCB_CONTEXT+1*8(%r3)
std %r14,PCB_CONTEXT+2*8(%r3)
std %r15,PCB_CONTEXT+3*8(%r3)
std %r16,PCB_CONTEXT+4*8(%r3)
std %r17,PCB_CONTEXT+5*8(%r3)
std %r18,PCB_CONTEXT+6*8(%r3)
std %r19,PCB_CONTEXT+7*8(%r3)
std %r20,PCB_CONTEXT+8*8(%r3)
std %r21,PCB_CONTEXT+9*8(%r3)
std %r22,PCB_CONTEXT+10*8(%r3)
std %r23,PCB_CONTEXT+11*8(%r3)
std %r24,PCB_CONTEXT+12*8(%r3)
std %r25,PCB_CONTEXT+13*8(%r3)
std %r26,PCB_CONTEXT+14*8(%r3)
std %r27,PCB_CONTEXT+15*8(%r3)
std %r28,PCB_CONTEXT+16*8(%r3)
std %r29,PCB_CONTEXT+17*8(%r3)
std %r30,PCB_CONTEXT+18*8(%r3)
std %r31,PCB_CONTEXT+19*8(%r3)
mfcr %r16 /* Save the condition register */
std %r16,PCB_CR(%r3)
mflr %r16 /* Save the link register */
std %r16,PCB_LR(%r3)
std %r1,PCB_SP(%r3) /* Save the stack pointer */
std %r2,PCB_TOC(%r3) /* Save the TOC pointer */
/* Set where we want to jump */
bl 1f
.llong power_save_sequence /* Remember about 8 byte alignment */
1: mflr %r3
ld %r3,0(%r3)
mtsrr0 %r3
/* Set MSR */
li %r3,0
ori %r3,%r3,(PSL_ME | PSL_RI)
li %r8,0x9 /* PSL_SF and PSL_HV */
insrdi %r3,%r8,4,0
mtsrr1 %r3
rfid
.p2align 2
CNAME(power_save_sequence):
bl 1f
.llong 0x0 /* Playground for power-save sequence */
1: mflr %r3
/* Start power-save sequence */
std %r2,0(%r3)
ptesync
ld %r2,0(%r3)
2: cmpd %r2,%r2
bne 2b
nap
b .