From patchwork Tue Feb 13 19:39:52 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Cave-Ayland X-Patchwork-Id: 1898417 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (4096-bit key; unprotected) header.d=ilande.co.uk header.i=@ilande.co.uk header.a=rsa-sha256 header.s=20220518 header.b=Q72zMpde; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4TZBd84c7Tz23hY for ; Wed, 14 Feb 2024 06:45:32 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rZygC-00079f-1H; Tue, 13 Feb 2024 14:42:56 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rZyg6-0006yI-Iw for qemu-devel@nongnu.org; Tue, 13 Feb 2024 14:42:50 -0500 Received: from mail.ilande.co.uk ([2001:41c9:1:41f::167]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rZyg5-0006Pk-0O for qemu-devel@nongnu.org; Tue, 13 Feb 2024 14:42:50 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=ilande.co.uk; s=20220518; h=Subject:Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:To:From:Sender:Reply-To:Cc: Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=kibjptY/wMmzUFXbCnZjWuBRPf2BC6ZaxFiieDa/v6k=; b=Q72zMpdeK6U2Vm5n1l8W8ZV07G OlOVLIWGhp/9FKlJ4ODCYvWie27zuXuulNs23GD7G1H3ZayYnMA3hlCdHv8DR+bQSgTZBWn31tUPg wAOUmEmNhIBLhE7PSSdz73Yrpdwfl+C1Zxz4AO+RyDAlMElEQp/dOOrBfJh1m1iPIX8juPZ9qlTA6 v6fZGlpwpCKji/QczyBsskFnaNnjzjeSk/ubkLForphtdRd05aQ/gg8z0Te9Db5ZcgSAIDOGzr22s CsGiP4FCpaCR9haJyGImJx22Uq/GJkJK8rCwl27fvKMy7qLwtTudOIWutWeuluFZB3dhQQIrs6Q5W RWdJxtZ7nxcua3vYGs/AUR8MUWq8rF9RF6c8l1WmKQhNkuVnhsu57UKDt7it0RdwTMSRoXcFybpZt qjkuZGs2LxV4nSEoEnOROePfFkUoABriP73fMQBw8Z/pJ3eHOHp2gZFiXMDWRK29N5dJZuS9defIB XCSDQA7dv78Tk2uWE6YUuLfkprD9Uq5v89SoZXXyBaRD5waNJ2btaCqPlF4Djd58jhxr4SzRPF6ng t+mpTAkY4cm5J2A0Hh8j6NS3t5StSF3nkQTVf9Oa4y0X/EDyKKRmr+hvVsiQr4m8gSCkzV1CJsvzx NPHnJuHBR6q4GzUc8GGXux1yVrTN/lsOCpW9C/VBI=; Received: from [2a00:23c4:8bb2:1300:c500:f104:bc51:e670] (helo=localhost.localdomain) by mail.ilande.co.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rZyfB-0008m4-K3; Tue, 13 Feb 2024 19:41:57 +0000 From: Mark Cave-Ayland To: peter.maydell@linaro.org, qemu-devel@nongnu.org Date: Tue, 13 Feb 2024 19:39:52 +0000 Message-Id: <20240213194052.1162753-29-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240213194052.1162753-1-mark.cave-ayland@ilande.co.uk> References: <20240213194052.1162753-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2a00:23c4:8bb2:1300:c500:f104:bc51:e670 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PULL 28/88] esp.c: consolidate async_len and TC == 0 checks in do_dma_pdma_cb() and esp_do_dma() X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.ilande.co.uk) Received-SPF: pass client-ip=2001:41c9:1:41f::167; envelope-from=mark.cave-ayland@ilande.co.uk; helo=mail.ilande.co.uk X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Ensure that the async_len checks for requesting data from the SCSI layer and the TC == 0 checks to detect the end of the DMA transfer are consistent in both do_dma_pdma_cb() and esp_do_dma(). In particular this involves adding the check to see if the FIFO is at its low threshold since PDMA and mixed DMA and non-DMA requests can leave data remaining in the FIFO. At the same time update all the comments so that they are also consistent between all similar code paths. Signed-off-by: Mark Cave-Ayland Tested-by: Helge Deller Tested-by: Thomas Huth Message-Id: <20240112125420.514425-29-mark.cave-ayland@ilande.co.uk> Signed-off-by: Mark Cave-Ayland --- hw/scsi/esp.c | 44 +++++++++++++++++++++++++++++++------------- 1 file changed, 31 insertions(+), 13 deletions(-) diff --git a/hw/scsi/esp.c b/hw/scsi/esp.c index 6b0811d3ce..f20026c3dc 100644 --- a/hw/scsi/esp.c +++ b/hw/scsi/esp.c @@ -604,12 +604,13 @@ static void do_dma_pdma_cb(ESPState *s) s->async_len -= n; s->ti_size += n; - if (s->async_len == 0) { + if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) { + /* Defer until the scsi layer has completed */ scsi_req_continue(s->current_req); return; } - if (esp_get_tc(s) == 0) { + if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) { esp_lower_drq(s); esp_dma_done(s); } @@ -706,24 +707,30 @@ static void esp_do_dma(ESPState *s) s->async_len -= len; s->ti_size += len; - if (s->async_len == 0) { + if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) { + /* Defer until the scsi layer has completed */ scsi_req_continue(s->current_req); - /* - * If there is still data to be read from the device then - * complete the DMA operation immediately. Otherwise defer - * until the scsi layer has completed. - */ return; } - if (esp_get_tc(s) == 0) { - /* Partially filled a scsi buffer. Complete immediately. */ + if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) { esp_dma_done(s); esp_lower_drq(s); } } else { esp_set_pdma_cb(s, DO_DMA_PDMA_CB); esp_raise_drq(s); + + if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) { + /* Defer until the scsi layer has completed */ + scsi_req_continue(s->current_req); + return; + } + + if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) { + esp_dma_done(s); + esp_lower_drq(s); + } } } else { if (s->dma_memory_write) { @@ -734,13 +741,13 @@ static void esp_do_dma(ESPState *s) s->async_len -= len; s->ti_size -= len; - if (s->async_len == 0) { + if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) { + /* Defer until the scsi layer has completed */ scsi_req_continue(s->current_req); return; } - if (esp_get_tc(s) == 0) { - /* Partially filled a scsi buffer. Complete immediately. */ + if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) { esp_dma_done(s); esp_lower_drq(s); } @@ -754,6 +761,17 @@ static void esp_do_dma(ESPState *s) esp_set_tc(s, esp_get_tc(s) - len); esp_set_pdma_cb(s, DO_DMA_PDMA_CB); esp_raise_drq(s); + + if (s->async_len == 0 && fifo8_num_used(&s->fifo) < 2) { + /* Defer until the scsi layer has completed */ + scsi_req_continue(s->current_req); + return; + } + + if (esp_get_tc(s) == 0 && fifo8_num_used(&s->fifo) < 2) { + esp_lower_drq(s); + esp_dma_done(s); + } } } }