Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933443AbbHDLGp (ORCPT ); Tue, 4 Aug 2015 07:06:45 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:33397 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933402AbbHDLGn (ORCPT ); Tue, 4 Aug 2015 07:06:43 -0400 X-Helo: d03dlp02.boulder.ibm.com X-MailFrom: ego@linux.vnet.ibm.com X-RcptTo: linux-kernel@vger.kernel.org From: "Gautham R. Shenoy" To: Paul Mackerras , Michael Ellerman , linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, mikey@neuling.org Cc: "Gautham R. Shenoy" Subject: [PATCH v2] powerpc: Add an inline function to update HID0 Date: Tue, 4 Aug 2015 16:36:24 +0530 Message-Id: <1438686384-15629-1-git-send-email-ego@linux.vnet.ibm.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <20150804105747.GA19966@in.ibm.com> References: <20150804105747.GA19966@in.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15080411-0013-0000-0000-000015B6E3A1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2379 Lines: 76 Section 3.7 of Version 1.2 of the Power8 Processor User's Manual prescribes that updates to HID0 be preceded by a SYNC instruction and followed by an ISYNC instruction (Page 91). Create an inline function name update_hid0() which follows this recipe and invoke it from the static split core path. Signed-off-by: Gautham R. Shenoy --- [v1--> v2: Moved defn of update_hid0 to reg.h from kvm_ppc.h] arch/powerpc/include/asm/reg.h | 13 +++++++++++++ arch/powerpc/platforms/powernv/subcore.c | 4 ++-- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index af56b5c..beb98ac 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -12,6 +12,8 @@ #include #include +#include +#include /* Pickup Book E specific registers. */ #if defined(CONFIG_BOOKE) || defined(CONFIG_40x) @@ -1281,6 +1283,17 @@ struct pt_regs; extern void ppc_save_regs(struct pt_regs *regs); +static inline void update_hid0(unsigned long hid0) +{ + /* + * The HID0 update should at the very least be preceded by a + * a SYNC instruction followed by an ISYNC instruction + */ + mb(); + mtspr(SPRN_HID0, hid0); + isync(); +} + #endif /* __ASSEMBLY__ */ #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_REG_H */ diff --git a/arch/powerpc/platforms/powernv/subcore.c b/arch/powerpc/platforms/powernv/subcore.c index f60f80a..37e77bf 100644 --- a/arch/powerpc/platforms/powernv/subcore.c +++ b/arch/powerpc/platforms/powernv/subcore.c @@ -190,7 +190,7 @@ static void unsplit_core(void) hid0 = mfspr(SPRN_HID0); hid0 &= ~HID0_POWER8_DYNLPARDIS; - mtspr(SPRN_HID0, hid0); + update_hid0(hid0); update_hid_in_slw(hid0); while (mfspr(SPRN_HID0) & mask) @@ -227,7 +227,7 @@ static void split_core(int new_mode) /* Write new mode */ hid0 = mfspr(SPRN_HID0); hid0 |= HID0_POWER8_DYNLPARDIS | split_parms[i].value; - mtspr(SPRN_HID0, hid0); + update_hid0(hid0); update_hid_in_slw(hid0); /* Wait for it to happen */ -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/