From patchwork Wed Nov 30 05:23:58 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Breeds X-Patchwork-Id: 128409 X-Patchwork-Delegate: jwboyer@gmail.com Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from ozlabs.org (localhost [IPv6:::1]) by ozlabs.org (Postfix) with ESMTP id A7E8910160C for ; Wed, 30 Nov 2011 16:24:54 +1100 (EST) Received: from localhost.localdomain (ibmaus65.lnk.telstra.net [165.228.126.9]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPSA id DA64B1007DA; Wed, 30 Nov 2011 16:24:06 +1100 (EST) From: Tony Breeds To: Benjamin Herrenschmidt , Josh Boyer Subject: [PATCH 4/6] powerpc/boot: Add extended precision shifts to the boot wrapper. Date: Wed, 30 Nov 2011 16:23:58 +1100 Message-Id: <1322630640-13708-5-git-send-email-tony@bakeyournoodle.com> X-Mailer: git-send-email 1.7.6.4 In-Reply-To: <1322630640-13708-1-git-send-email-tony@bakeyournoodle.com> References: <1322630640-13708-1-git-send-email-tony@bakeyournoodle.com> Cc: LinuxPPC-dev X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Code copied from arch/powerpc/kernel/misc_32.S Signed-off-by: Tony Breeds --- arch/powerpc/boot/div64.S | 52 +++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 52 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/boot/div64.S b/arch/powerpc/boot/div64.S index d271ab5..bbcb8a4 100644 --- a/arch/powerpc/boot/div64.S +++ b/arch/powerpc/boot/div64.S @@ -57,3 +57,55 @@ __div64_32: stw r8,4(r3) mr r3,r6 # return the remainder in r3 blr + +/* + * Extended precision shifts. + * + * Updated to be valid for shift counts from 0 to 63 inclusive. + * -- Gabriel + * + * R3/R4 has 64 bit value + * R5 has shift count + * result in R3/R4 + * + * ashrdi3: arithmetic right shift (sign propagation) + * lshrdi3: logical right shift + * ashldi3: left shift + */ + .globl __ashrdi3 +__ashrdi3: + subfic r6,r5,32 + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count + addi r7,r5,32 # could be xori, or addi with -32 + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) + rlwinm r8,r7,0,32 # t3 = (count < 32) ? 32 : 0 + sraw r7,r3,r7 # t2 = MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + slw r7,r7,r8 # t2 = (count < 32) ? 0 : t2 + sraw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr + + .globl __ashldi3 +__ashldi3: + subfic r6,r5,32 + slw r3,r3,r5 # MSW = count > 31 ? 0 : MSW << count + addi r7,r5,32 # could be xori, or addi with -32 + srw r6,r4,r6 # t1 = count > 31 ? 0 : LSW >> (32-count) + slw r7,r4,r7 # t2 = count < 32 ? 0 : LSW << (count-32) + or r3,r3,r6 # MSW |= t1 + slw r4,r4,r5 # LSW = LSW << count + or r3,r3,r7 # MSW |= t2 + blr + + .globl __lshrdi3 +__lshrdi3: + subfic r6,r5,32 + srw r4,r4,r5 # LSW = count > 31 ? 0 : LSW >> count + addi r7,r5,32 # could be xori, or addi with -32 + slw r6,r3,r6 # t1 = count > 31 ? 0 : MSW << (32-count) + srw r7,r3,r7 # t2 = count < 32 ? 0 : MSW >> (count-32) + or r4,r4,r6 # LSW |= t1 + srw r3,r3,r5 # MSW = MSW >> count + or r4,r4,r7 # LSW |= t2 + blr