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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 76EF5C433DF for ; Mon, 29 Jun 2020 01:39:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 583E32076C for ; Mon, 29 Jun 2020 01:39:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726613AbgF2BjF (ORCPT ); Sun, 28 Jun 2020 21:39:05 -0400 Received: from regular1.263xmail.com ([211.150.70.198]:58234 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726465AbgF2BjF (ORCPT ); Sun, 28 Jun 2020 21:39:05 -0400 Received: from localhost (unknown [192.168.167.69]) by regular1.263xmail.com (Postfix) with ESMTP id AA9956C9; Mon, 29 Jun 2020 09:38:55 +0800 (CST) X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-ADDR-CHECKED4: 1 X-ANTISPAM-LEVEL: 2 X-SKE-CHECKED: 1 X-ABS-CHECKED: 1 Received: from [172.16.12.19] (unknown [58.22.7.114]) by smtp.263.net (postfix) whith ESMTP id P31014T140189206046464S1593394734261642_; Mon, 29 Jun 2020 09:38:54 +0800 (CST) X-IP-DOMAINF: 1 X-UNIQUE-TAG: <2727d7686c637f3bd7561c7dd98d7f80> X-RL-SENDER: sugar.zhang@rock-chips.com X-SENDER: zxg@rock-chips.com X-LOGIN-NAME: sugar.zhang@rock-chips.com X-FST-TO: linux-kernel@vger.kernel.org X-SENDER-IP: 58.22.7.114 X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 X-System-Flag: 0 Subject: Re: [PATCH v2 01/13] dmaengine: pl330: Remove the burst limit for quirk 'NO-FLUSHP' To: Vinod Koul Cc: Heiko Stuebner , linux-rockchip@lists.infradead.org, Dan Williams , dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org References: <1591665267-37713-1-git-send-email-sugar.zhang@rock-chips.com> <1591665267-37713-2-git-send-email-sugar.zhang@rock-chips.com> <20200624075437.GT2324254@vkoul-mobl> From: sugar zhang Message-ID: <879c88ef-1d74-26d5-1641-efeb450362fa@rock-chips.com> Date: Mon, 29 Jun 2020 09:38:54 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: <20200624075437.GT2324254@vkoul-mobl> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org On 2020/6/24 15:54, Vinod Koul wrote: > On 09-06-20, 09:14, Sugar Zhang wrote: >> There is no reason to limit the performance on the 'NO-FLUSHP' SoCs, >> cuz these platforms are just that the 'FLUSHP' instruction is broken. > Lets not use terms like cuz... 'because' is perfect term :) > > It can rephrased to: > There is no reason to limit the performance on the 'NO-FLUSHP' SoCs > beacuse 'FLUSHP' instruction is broken on these platforms, so remove the > limit to improve the efficiency Thanks, I will send a v3 including these. > >> so, remove the limit to improve the efficiency. >> >> Signed-off-by: Sugar Zhang >> --- >> >> Changes in v2: None >> >> drivers/dma/pl330.c | 34 ++++++++++++++++++++++------------ >> 1 file changed, 22 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c >> index 6a158ee..ff0a91f 100644 >> --- a/drivers/dma/pl330.c >> +++ b/drivers/dma/pl330.c >> @@ -1183,9 +1183,6 @@ static inline int _ldst_peripheral(struct pl330_dmac *pl330, >> { >> int off = 0; >> >> - if (pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) >> - cond = BURST; >> - >> /* >> * do FLUSHP at beginning to clear any stale dma requests before the >> * first WFP. >> @@ -1231,8 +1228,9 @@ static int _bursts(struct pl330_dmac *pl330, unsigned dry_run, u8 buf[], >> } >> >> /* >> - * transfer dregs with single transfers to peripheral, or a reduced size burst >> - * for mem-to-mem. >> + * only the unaligned bursts transfers have the dregs. >> + * transfer dregs with a reduced size burst to peripheral, >> + * or a reduced size burst for mem-to-mem. > This is not related to broken flush and should be a different patch > explaining why this changes were done ok, I will split this patch in v3. >> */ >> static int _dregs(struct pl330_dmac *pl330, unsigned int dry_run, u8 buf[], >> const struct _xfer_spec *pxs, int transfer_length) >> @@ -1247,8 +1245,23 @@ static int _dregs(struct pl330_dmac *pl330, unsigned int dry_run, u8 buf[], >> case DMA_MEM_TO_DEV: >> /* fall through */ >> case DMA_DEV_TO_MEM: >> - off += _ldst_peripheral(pl330, dry_run, &buf[off], pxs, >> - transfer_length, SINGLE); >> + /* >> + * dregs_len = (total bytes - BURST_TO_BYTE(bursts, ccr)) / >> + * BRST_SIZE(ccr) >> + * the dregs len must be smaller than burst len, >> + * so, for higher efficiency, we can modify CCR >> + * to use a reduced size burst len for the dregs. >> + */ >> + dregs_ccr = pxs->ccr; >> + dregs_ccr &= ~((0xf << CC_SRCBRSTLEN_SHFT) | >> + (0xf << CC_DSTBRSTLEN_SHFT)); >> + dregs_ccr |= (((transfer_length - 1) & 0xf) << >> + CC_SRCBRSTLEN_SHFT); >> + dregs_ccr |= (((transfer_length - 1) & 0xf) << >> + CC_DSTBRSTLEN_SHFT); >> + off += _emit_MOV(dry_run, &buf[off], CCR, dregs_ccr); >> + off += _ldst_peripheral(pl330, dry_run, &buf[off], pxs, 1, >> + BURST); >> break; >> >> case DMA_MEM_TO_MEM: >> @@ -2221,9 +2234,7 @@ static bool pl330_prep_slave_fifo(struct dma_pl330_chan *pch, >> >> static int fixup_burst_len(int max_burst_len, int quirks) >> { >> - if (quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) >> - return 1; >> - else if (max_burst_len > PL330_MAX_BURST) >> + if (max_burst_len > PL330_MAX_BURST) >> return PL330_MAX_BURST; >> else if (max_burst_len < 1) >> return 1; >> @@ -3128,8 +3139,7 @@ pl330_probe(struct amba_device *adev, const struct amba_id *id) >> pd->dst_addr_widths = PL330_DMA_BUSWIDTHS; >> pd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV); >> pd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST; >> - pd->max_burst = ((pl330->quirks & PL330_QUIRK_BROKEN_NO_FLUSHP) ? >> - 1 : PL330_MAX_BURST); >> + pd->max_burst = PL330_MAX_BURST; >> >> ret = dma_async_device_register(pd); >> if (ret) { >> -- >> 2.7.4 >> >> --