From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3159FC433FE for ; Wed, 23 Mar 2022 11:10:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243744AbiCWLLi (ORCPT ); Wed, 23 Mar 2022 07:11:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59382 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239920AbiCWLLg (ORCPT ); Wed, 23 Mar 2022 07:11:36 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 07FF878061; Wed, 23 Mar 2022 04:10:06 -0700 (PDT) Received: from kwepemi500017.china.huawei.com (unknown [172.30.72.54]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4KNlsD5kC9zBrWR; Wed, 23 Mar 2022 19:06:08 +0800 (CST) Received: from [10.67.103.235] (10.67.103.235) by kwepemi500017.china.huawei.com (7.221.188.110) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Wed, 23 Mar 2022 19:10:04 +0800 Subject: Re: [PATCH] dmaengine: hisi_dma: fix MSI allocate fail when reload hisi_dma To: Jie Hai , , References: <20220216072101.34473-1-haijie1@huawei.com> CC: , From: Dongdong Liu Message-ID: Date: Wed, 23 Mar 2022 19:10:04 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20220216072101.34473-1-haijie1@huawei.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.103.235] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To kwepemi500017.china.huawei.com (7.221.188.110) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Looks good. Reviewed-by: Dongdong Liu Thanks, Dongdong On 2022/2/16 15:21, Jie Hai wrote: > Remove the loaded hisi_dma driver and reload it, the driver fails > to work properly. The following error is reported in the kernel log: > > [ 1475.597609] hisi_dma 0000:7b:00.0: Failed to allocate MSI vectors! > [ 1475.604915] hisi_dma: probe of 0000:7b:00.0 failed with error -28 > > As noted in "The MSI Driver Guide HOWTO"[1], the number of MSI > interrupt must be a power of two. The Kunpeng DMA driver allocates 30 > MSI interrupts. As a result, no space left on device is reported > when the driver is reloaded and allocates interrupt vectors from the > interrupt domain. > > This patch changes the number of interrupt vectors allocated by > hisi_dma driver to 32 to avoid this problem. > > [1] https://www.kernel.org/doc/html/latest/PCI/msi-howto.html > > Fixes: e9f08b65250d ("dmaengine: hisilicon: Add Kunpeng DMA engine support") > > Signed-off-by: Jie Hai > --- > drivers/dma/hisi_dma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/dma/hisi_dma.c b/drivers/dma/hisi_dma.c > index 97c87a7cba87..43817ced3a3e 100644 > --- a/drivers/dma/hisi_dma.c > +++ b/drivers/dma/hisi_dma.c > @@ -30,7 +30,7 @@ > #define HISI_DMA_MODE 0x217c > #define HISI_DMA_OFFSET 0x100 > > -#define HISI_DMA_MSI_NUM 30 > +#define HISI_DMA_MSI_NUM 32 > #define HISI_DMA_CHAN_NUM 30 > #define HISI_DMA_Q_DEPTH_VAL 1024 > >