From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id E9E261A0187 for ; Tue, 7 Oct 2014 16:22:31 +1100 (EST) Message-ID: <1412659338.30859.145.camel@pasglop> Subject: Re: [PATCH v2 1/5] powerpc/powernv: Add OPAL call to save and restore From: Benjamin Herrenschmidt To: "Shreyas B. Prabhu" Date: Tue, 07 Oct 2014 16:22:18 +1100 In-Reply-To: <1412149617-3178-2-git-send-email-shreyas@linux.vnet.ibm.com> References: <1412149617-3178-1-git-send-email-shreyas@linux.vnet.ibm.com> <1412149617-3178-2-git-send-email-shreyas@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 Cc: Paul Mackerras , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, 2014-10-01 at 13:16 +0530, Shreyas B. Prabhu wrote: > PORE can be programmed to restore hypervisor registers when waking up > from deep cpu idle states like winkle. Tell us a bit more about what "PORE" is. IE, explain a tiny engine will reconfigure the core and its ucode can be patched to provide some registers with sane values. > Add call to pass SPR address and value to OPAL, which in turn will > program PORE to restore the register state. Otherwise, Acke-by: Benjamin Herrenschmidt > Cc: Paul Mackerras > Cc: Michael Ellerman > Suggested-by: Vaidyanathan Srinivasan > Signed-off-by: Shreyas B. Prabhu > --- > arch/powerpc/include/asm/opal.h | 2 ++ > arch/powerpc/platforms/powernv/opal-wrappers.S | 1 + > 2 files changed, 3 insertions(+) > > diff --git a/arch/powerpc/include/asm/opal.h b/arch/powerpc/include/asm/opal.h > index 166d572..d376020 100644 > --- a/arch/powerpc/include/asm/opal.h > +++ b/arch/powerpc/include/asm/opal.h > @@ -150,6 +150,7 @@ struct opal_sg_list { > #define OPAL_PCI_EEH_FREEZE_SET 97 > #define OPAL_HANDLE_HMI 98 > #define OPAL_CONFIG_IDLE_STATE 99 > +#define OPAL_SLW_SET_REG 100 > #define OPAL_REGISTER_DUMP_REGION 101 > #define OPAL_UNREGISTER_DUMP_REGION 102 > > @@ -978,6 +979,7 @@ extern int opal_handle_hmi_exception(struct pt_regs *regs); > extern void opal_shutdown(void); > extern int opal_resync_timebase(void); > int64_t opal_config_idle_state(uint64_t state, uint64_t enter); > +int64_t opal_slw_set_reg(uint64_t cpu_pir, uint64_t sprn, uint64_t val); > > extern void opal_lpc_init(void); > > diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S > index 8d1e724..12e5d46 100644 > --- a/arch/powerpc/platforms/powernv/opal-wrappers.S > +++ b/arch/powerpc/platforms/powernv/opal-wrappers.S > @@ -246,5 +246,6 @@ OPAL_CALL(opal_get_param, OPAL_GET_PARAM); > OPAL_CALL(opal_set_param, OPAL_SET_PARAM); > OPAL_CALL(opal_handle_hmi, OPAL_HANDLE_HMI); > OPAL_CALL(opal_config_idle_state, OPAL_CONFIG_IDLE_STATE); > +OPAL_CALL(opal_slw_set_reg, OPAL_SLW_SET_REG); > OPAL_CALL(opal_register_dump_region, OPAL_REGISTER_DUMP_REGION); > OPAL_CALL(opal_unregister_dump_region, OPAL_UNREGISTER_DUMP_REGION);