From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754902Ab0CYPZQ (ORCPT ); Thu, 25 Mar 2010 11:25:16 -0400 Received: from mail-bw0-f209.google.com ([209.85.218.209]:43436 "EHLO mail-bw0-f209.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754874Ab0CYPZM (ORCPT ); Thu, 25 Mar 2010 11:25:12 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:subject:to:cc:date:message-id:user-agent:mime-version :content-type:content-transfer-encoding; b=TmN6L3ysXU7f7GHjeqKYZrzS6RUoE32m0GanXUj+QzqoWZkkSt5g40x0n8sNsy5DRD sD7iNooXE60cY3t0S16lgIonxnXS2/vUj351i7PGla7CmuF/yBfPDxLmyhPtGwOynPFf KHqKTyBee7J2zE405oOosBwiPvBnFRZu7b9ig= From: Paulius Zaleckas Subject: [PATCH v2] MTD: Fix Orion NAND driver compilation with ARM OABI To: dwmw2@infradead.org Cc: nico@fluxnic.net, akpm@linux-foundation.org, u.kleine-koenig@pengutronix.de, simon.kagstrom@netinsight.net, linux-mtd@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Date: Thu, 25 Mar 2010 17:25:05 +0200 Message-ID: <20100325152505.17612.40158.stgit@pauliusz> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We must tell GCC to use even register for variable passed to ldrd instruction. Without this patch GCC 4.2.1 puts this variable to r2/r3 on EABI and r3/r4 on OABI, so force it to r2/r3. This does not change anything when EABI and OABI compilation works OK. Without this patch and with OABI I get: CC drivers/mtd/nand/orion_nand.o /tmp/ccMkwOCs.s: Assembler messages: /tmp/ccMkwOCs.s:63: Error: first destination register must be even -- `ldrd r3,[ip]' make[5]: *** [drivers/mtd/nand/orion_nand.o] Error 1 Signed-off-by: Paulius Zaleckas --- drivers/mtd/nand/orion_nand.c | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/drivers/mtd/nand/orion_nand.c b/drivers/mtd/nand/orion_nand.c index f59c074..d60fc57 100644 --- a/drivers/mtd/nand/orion_nand.c +++ b/drivers/mtd/nand/orion_nand.c @@ -60,7 +60,13 @@ static void orion_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len) } buf64 = (uint64_t *)buf; while (i < len/8) { - uint64_t x; + /* + * Since GCC has no proper constraint (PR 43518) + * force x variable to r2/r3 registers as ldrd instruction + * requires first register to be even. + */ + register uint64_t x asm ("r2"); + asm volatile ("ldrd\t%0, [%1]" : "=&r" (x) : "r" (io_base)); buf64[i++] = x; }