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Violators will be prosecuted; Fri, 29 Nov 2013 05:45:39 -0500 Received: from b01cxnp23032.gho.pok.ibm.com (b01cxnp23032.gho.pok.ibm.com [9.57.198.27]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id BDD07C90041 for ; Fri, 29 Nov 2013 05:45:37 -0500 (EST) Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by b01cxnp23032.gho.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id rATAjdaZ4063688 for ; Fri, 29 Nov 2013 10:45:39 GMT Received: from d01av02.pok.ibm.com (localhost [127.0.0.1]) by d01av02.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id rATAjbkY027210 for ; Fri, 29 Nov 2013 05:45:39 -0500 Received: from preeti.in.ibm.com ([9.79.202.217]) by d01av02.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id rATAjRkA026841; Fri, 29 Nov 2013 05:45:29 -0500 Subject: [PATCH V4 4/9] powernv/cpuidle: Add context management for Fast Sleep To: fweisbec@gmail.com, paul.gortmaker@windriver.com, paulus@samba.org, shangw@linux.vnet.ibm.com, rjw@sisk.pl, galak@kernel.crashing.org, benh@kernel.crashing.org, paulmck@linux.vnet.ibm.com, arnd@arndb.de, linux-pm@vger.kernel.org, rostedt@goodmis.org, michael@ellerman.id.au, john.stultz@linaro.org, tglx@linutronix.de, chenhui.zhao@freescale.com, deepthi@linux.vnet.ibm.com, r58472@freescale.com, geoff@infradead.org, linux-kernel@vger.kernel.org, srivatsa.bhat@linux.vnet.ibm.com, schwidefsky@de.ibm.com, svaidy@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org From: Preeti U Murthy Date: Fri, 29 Nov 2013 16:12:21 +0530 Message-ID: <20131129104220.651.30125.stgit@preeti.in.ibm.com> In-Reply-To: <20131129104010.651.23117.stgit@preeti.in.ibm.com> References: <20131129104010.651.23117.stgit@preeti.in.ibm.com> User-Agent: StGit/0.16-38-g167d MIME-Version: 1.0 X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13112910-7182-0000-0000-0000093B6621 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.16 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Vaidyanathan Srinivasan Before adding Fast-Sleep into the cpuidle framework, some low level support needs to be added to enable it. This includes saving and restoring of certain registers at entry and exit time of this state respectively just like we do in the NAP idle state. Signed-off-by: Vaidyanathan Srinivasan [Changelog modified by Preeti U. Murthy ] Signed-off-by: Preeti U. Murthy --- arch/powerpc/include/asm/processor.h | 1 + arch/powerpc/kernel/exceptions-64s.S | 10 ++++- arch/powerpc/kernel/idle_power7.S | 63 ++++++++++++++++++++++++---------- 3 files changed, 53 insertions(+), 21 deletions(-) diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index 4f7b047..d7633d0 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -444,6 +444,7 @@ enum idle_boot_override {IDLE_NO_OVERRIDE = 0, IDLE_POWERSAVE_OFF}; extern int powersave_nap; /* set if nap mode can be used in idle loop */ extern void power7_nap(void); +extern void power7_sleep(void); #ifdef CONFIG_CPU_IDLE_POWERPC_BOOK3S extern void update_smt_snooze_delay(int cpu, int residency); diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 9f905e4..b8139fb 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -121,9 +121,10 @@ BEGIN_FTR_SECTION cmpwi cr1,r13,2 /* Total loss of HV state is fatal, we could try to use the * PIR to locate a PACA, then use an emergency stack etc... - * but for now, let's just stay stuck here + * OPAL v3 based powernv platforms have new idle states + * which fall in this catagory. */ - bgt cr1,. + bgt cr1,8f GET_PACA(r13) #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE @@ -141,6 +142,11 @@ BEGIN_FTR_SECTION beq cr1,2f b .power7_wakeup_noloss 2: b .power7_wakeup_loss + + /* Fast Sleep wakeup on PowerNV */ +8: GET_PACA(r13) + b .power7_wakeup_loss + 9: END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206) #endif /* CONFIG_PPC_P7_NAP */ diff --git a/arch/powerpc/kernel/idle_power7.S b/arch/powerpc/kernel/idle_power7.S index 847e40e..e4bbca2 100644 --- a/arch/powerpc/kernel/idle_power7.S +++ b/arch/powerpc/kernel/idle_power7.S @@ -20,17 +20,27 @@ #undef DEBUG - .text +/* Idle state entry routines */ -_GLOBAL(power7_idle) - /* Now check if user or arch enabled NAP mode */ - LOAD_REG_ADDRBASE(r3,powersave_nap) - lwz r4,ADDROFF(powersave_nap)(r3) - cmpwi 0,r4,0 - beqlr - /* fall through */ +#define IDLE_STATE_ENTER_SEQ(IDLE_INST) \ + /* Magic NAP/SLEEP/WINKLE mode enter sequence */ \ + std r0,0(r1); \ + ptesync; \ + ld r0,0(r1); \ +1: cmp cr0,r0,r0; \ + bne 1b; \ + IDLE_INST; \ + b . -_GLOBAL(power7_nap) + .text + +/* + * Pass requested state in r3: + * 0 - nap + * 1 - sleep + */ +_GLOBAL(power7_powersave_common) + /* Use r3 to pass state nap/sleep/winkle */ /* NAP is a state loss, we create a regs frame on the * stack, fill it up with the state we care about and * stick a pointer to it in PACAR1. We really only @@ -79,8 +89,8 @@ _GLOBAL(power7_nap) /* Continue saving state */ SAVE_GPR(2, r1) SAVE_NVGPRS(r1) - mfcr r3 - std r3,_CCR(r1) + mfcr r4 + std r4,_CCR(r1) std r9,_MSR(r1) std r1,PACAR1(r13) @@ -89,15 +99,30 @@ _GLOBAL(power7_nap) li r4,KVM_HWTHREAD_IN_NAP stb r4,HSTATE_HWTHREAD_STATE(r13) #endif + cmpwi cr0,r3,1 + beq 2f + IDLE_STATE_ENTER_SEQ(PPC_NAP) + /* No return */ +2: IDLE_STATE_ENTER_SEQ(PPC_SLEEP) + /* No return */ - /* Magic NAP mode enter sequence */ - std r0,0(r1) - ptesync - ld r0,0(r1) -1: cmp cr0,r0,r0 - bne 1b - PPC_NAP - b . +_GLOBAL(power7_idle) + /* Now check if user or arch enabled NAP mode */ + LOAD_REG_ADDRBASE(r3,powersave_nap) + lwz r4,ADDROFF(powersave_nap)(r3) + cmpwi 0,r4,0 + beqlr + /* fall through */ + +_GLOBAL(power7_nap) + li r3,0 + b power7_powersave_common + /* No return */ + +_GLOBAL(power7_sleep) + li r3,1 + b power7_powersave_common + /* No return */ _GLOBAL(power7_wakeup_loss) ld r1,PACAR1(r13)