From patchwork Wed Jun 17 23:40:22 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11610973 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9DF231392 for ; Wed, 17 Jun 2020 23:41:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 90819218AC for ; Wed, 17 Jun 2020 23:41:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726971AbgFQXkp (ORCPT ); Wed, 17 Jun 2020 19:40:45 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:57800 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726854AbgFQXko (ORCPT ); Wed, 17 Jun 2020 19:40:44 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id DB729803202E; Wed, 17 Jun 2020 23:40:41 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QUcOk74t3rAu; Thu, 18 Jun 2020 02:40:40 +0300 (MSK) From: Serge Semin To: Vinod Koul , Viresh Kumar , Dan Williams CC: Serge Semin , Serge Semin , Andy Shevchenko , Alexey Malahov , Thomas Bogendoerfer , Arnd Bergmann , Rob Herring , , , , Subject: [PATCH v6 3/9] dmaengine: Introduce min burst length capability Date: Thu, 18 Jun 2020 02:40:22 +0300 Message-ID: <20200617234028.25808-4-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20200617234028.25808-1-Sergey.Semin@baikalelectronics.ru> References: <20200617234028.25808-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Some hardware aside from default 0/1 may have greater minimum burst transactions length constraints. Here we introduce the DMA device and slave capability, which if required can be initialized by the DMA engine driver with the device-specific value. Signed-off-by: Serge Semin Reviewed-by: Andy Shevchenko Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Arnd Bergmann Cc: Rob Herring Cc: linux-mips@vger.kernel.org Cc: devicetree@vger.kernel.org --- Changelog v3: - This is a new patch created as a result of the discussion with Vinud and Andy in the framework of DW DMA burst and LLP capabilities. --- drivers/dma/dmaengine.c | 1 + include/linux/dmaengine.h | 4 ++++ 2 files changed, 5 insertions(+) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index d31076d9ef25..b332ffe52780 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -590,6 +590,7 @@ int dma_get_slave_caps(struct dma_chan *chan, struct dma_slave_caps *caps) caps->src_addr_widths = device->src_addr_widths; caps->dst_addr_widths = device->dst_addr_widths; caps->directions = device->directions; + caps->min_burst = device->min_burst; caps->max_burst = device->max_burst; caps->residue_granularity = device->residue_granularity; caps->descriptor_reuse = device->descriptor_reuse; diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index e1c03339918f..0c7403b27133 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -465,6 +465,7 @@ enum dma_residue_granularity { * Since the enum dma_transfer_direction is not defined as bit flag for * each type, the dma controller should set BIT() and same * should be checked by controller as well + * @min_burst: min burst capability per-transfer * @max_burst: max burst capability per-transfer * @cmd_pause: true, if pause is supported (i.e. for reading residue or * for resume later) @@ -478,6 +479,7 @@ struct dma_slave_caps { u32 src_addr_widths; u32 dst_addr_widths; u32 directions; + u32 min_burst; u32 max_burst; bool cmd_pause; bool cmd_resume; @@ -769,6 +771,7 @@ struct dma_filter { * Since the enum dma_transfer_direction is not defined as bit flag for * each type, the dma controller should set BIT() and same * should be checked by controller as well + * @min_burst: min burst capability per-transfer * @max_burst: max burst capability per-transfer * @residue_granularity: granularity of the transfer residue reported * by tx_status @@ -839,6 +842,7 @@ struct dma_device { u32 src_addr_widths; u32 dst_addr_widths; u32 directions; + u32 min_burst; u32 max_burst; bool descriptor_reuse; enum dma_residue_granularity residue_granularity;