From patchwork Tue Aug 13 15:47:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11092505 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B2EAE912 for ; Tue, 13 Aug 2019 15:48:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A25BC2842A for ; Tue, 13 Aug 2019 15:48:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A052E286D5; Tue, 13 Aug 2019 15:48:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 551E02842A for ; Tue, 13 Aug 2019 15:48:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=cB7gbA75siUbHZEcjj0sNChM/3o02GZDzVZu2JUpwKc=; b=FS7pMyl1R4IXwX 5ZosFD2s3I/voxqV2R9rK1+fGJsnbIw4qFWoD4U3uiMuIySXFISGs2aB+kNDYkOmKQ34WOxTe8MHh V6yzsHC5BBSVnNvTtAQDZkGZk4CZgiMoHPUlBn2HAoLimBX58KT52MBfndIAWfuBX+3OS3OSbevOq yh1p+27p2RXqITjUtbXnOlLgG51KldcLolxAASB8kdmnbN+Ke0dC9DvWPFuhuIYQgBAjErtYDt6xo 2BJ4LPiu0Nv2p5HpcCx5zNXSb9yNgygXTaJMfkubRN/k38bLfKqT9BJQQ2rU1EIkv9h4AegtkBjM1 em8+Yb6UtedYqQV+dibg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hxZ1r-0004zW-19; Tue, 13 Aug 2019 15:48:07 +0000 Received: from [2001:4bb8:180:1ec3:c70:4a89:bc61:2] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hxZ1m-0004tx-V9; Tue, 13 Aug 2019 15:48:03 +0000 From: Christoph Hellwig To: Palmer Dabbelt , Paul Walmsley Subject: [PATCH 05/15] riscv: improve the default power off implementation Date: Tue, 13 Aug 2019 17:47:37 +0200 Message-Id: <20190813154747.24256-6-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190813154747.24256-1-hch@lst.de> References: <20190813154747.24256-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Atish Patra , Damien Le Moal , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Only call the SBI code if we are not running in M mode, and if we didn't do the SBI call, or it didn't succeed call wfi in a loop to at least save some power. Signed-off-by: Christoph Hellwig Reviewed-by: Atish Patra --- arch/riscv/kernel/reset.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/riscv/kernel/reset.c b/arch/riscv/kernel/reset.c index d0fe623bfb8f..2f5ca379747e 100644 --- a/arch/riscv/kernel/reset.c +++ b/arch/riscv/kernel/reset.c @@ -8,8 +8,11 @@ static void default_power_off(void) { +#ifndef CONFIG_M_MODE sbi_shutdown(); - while (1); +#endif + while (1) + wait_for_interrupt(); } void (*pm_power_off)(void) = default_power_off;