From nobody Sat Sep 21 07:48:47 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=ilande.co.uk Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1705065497906333.45108210838634; Fri, 12 Jan 2024 05:18:17 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rOHOk-0005H3-Np; Fri, 12 Jan 2024 08:16:35 -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 1rOHO8-00048A-HX for qemu-devel@nongnu.org; Fri, 12 Jan 2024 08:15:58 -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 1rOHO5-0008Ot-Kq for qemu-devel@nongnu.org; Fri, 12 Jan 2024 08:15:55 -0500 Received: from [2a02:8012:c93d:0:260e:bf57:a4e9:8142] (helo=cheesecake.fritz.box) by mail.ilande.co.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1rOHNR-0009Gy-BX; Fri, 12 Jan 2024 13:15:13 +0000 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=rtIL/xArmXp0Q2gT0KvSPBmNZgN/sj4zdhvxT3nWGFo=; b=iuMlAdohPt7IeAlMiye9mGGKCk swW3dSKndKr2yO4OyKjxkOAt9yiq1rkbwDlFoyouIVSkz2DaovzBTOADks5ORr9FY8tvTgfyxYPhn brvpbCq+SOGTtJgoSddL4SRemnh8ii5npwpxXEQqvAqyR2XopkJU6hQ752Zqc7n9CBpL9hVfDDF9m dvnbYKdpBXtItV9LZLIf2tuvxi8Wd9WURYxBj3sgt29QIsT7HI7fRvg9mQKxS6OW+QYr1WXyZjLA/ IKaHvsJq068+0Ck8CZO9Cd2g6sGYb6GYQXRJnKBHY3rx0MKPdtRXYwbl4OHeZfh+CLJT/rpsHTcMW 41BAXizVqswoN13mS5n6AekSTkqgDqVcNTM19GCrU2h2wJG2X2rAF30MntVQDVpTuH2TEcu8FxXUR zCbWfdaX5T8Kv7zRQaAGz7SEL+raUh8UXlHTawGzhCGkVjzoa3+Wy3U7D+CLKWXMcZg+I2AlWIk0K mAV3EQqSaZBtw6UMhTFrwcbGUohv5LVOkpX0oyrPuM4VYZN0YeP8a/sg/YRbXrsP6tP1MmmX10+ea cTS0oZMWBqqeBn0oBFZOk8T0DgsCaGFl7E1w+2Uo9HssquPi09F+RcOKeYu72Mht9d064ix2Bxfyo XDE+r0hxByBasdLIac49TIjbTpqBEpPVqOf1alVYI=; From: Mark Cave-Ayland To: pbonzini@redhat.com, fam@euphon.net, hpoussin@reactos.org, deller@gmx.de, linux@roeck-us.net, qemu-devel@nongnu.org Date: Fri, 12 Jan 2024 13:15:28 +0000 Message-Id: <20240112131529.515642-4-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240112131529.515642-1-mark.cave-ayland@ilande.co.uk> References: <20240112131529.515642-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-SA-Exim-Connect-IP: 2a02:8012:c93d:0:260e:bf57:a4e9:8142 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH 3/4] esp-pci.c: synchronise setting of DMA_STAT_DONE with ESP completion interrupt 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 (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; 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+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZM-MESSAGEID: 1705065499497100001 Content-Type: text/plain; charset="utf-8" The setting of DMA_STAT_DONE at the end of a DMA transfer can be configured= to generate an interrupt, however the Linux driver manually checks for DMA_STA= T_DONE being set and if it is, considers that a DMA transfer has completed. If DMA_STAT_DONE is set but the ESP device isn't indicating an interrupt th= en the Linux driver considers this to be a spurious interrupt. However this can occur in QEMU as there is a delay between the end of DMA transfer where DMA_STAT_DONE is set, and the ESP device raising its completion interrupt. This appears to be an incorrect assumption in the Linux driver as the ESP a= nd PCI DMA interrupt sources are separate (and may not be raised exactly together), however we can work around this by synchronising the setting of DMA_STAT_DONE at the end of a DMA transfer with the ESP completion interrup= t. In conjunction with the previous commit Linux is now able to correctly boot from an am53c974 PCI SCSI device on the hppa C3700 machine without emitting "iget: checksum invalid" and "Spurious irq, sreg=3D10" errors. Signed-off-by: Mark Cave-Ayland Reviewed-by: Guenter Roeck Tested-by: Guenter Roeck --- hw/scsi/esp-pci.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/hw/scsi/esp-pci.c b/hw/scsi/esp-pci.c index 15dc3c004d..875a49199d 100644 --- a/hw/scsi/esp-pci.c +++ b/hw/scsi/esp-pci.c @@ -93,6 +93,18 @@ static void esp_irq_handler(void *opaque, int irq_num, i= nt level) =20 if (level) { pci->dma_regs[DMA_STAT] |=3D DMA_STAT_SCSIINT; + + /* + * If raising the ESP IRQ to indicate end of DMA transfer, set + * DMA_STAT_DONE at the same time. In theory this should be done in + * esp_pci_dma_memory_rw(), however there is a delay between setti= ng + * DMA_STAT_DONE and the ESP IRQ arriving which is visible to the + * guest that can cause confusion e.g. Linux + */ + if ((pci->dma_regs[DMA_CMD] & DMA_CMD_MASK) =3D=3D 0x3 && + pci->dma_regs[DMA_WBC] =3D=3D 0) { + pci->dma_regs[DMA_STAT] |=3D DMA_STAT_DONE; + } } else { pci->dma_regs[DMA_STAT] &=3D ~DMA_STAT_SCSIINT; } @@ -306,9 +318,6 @@ static void esp_pci_dma_memory_rw(PCIESPState *pci, uin= t8_t *buf, int len, /* update status registers */ pci->dma_regs[DMA_WBC] -=3D len; pci->dma_regs[DMA_WAC] +=3D len; - if (pci->dma_regs[DMA_WBC] =3D=3D 0) { - pci->dma_regs[DMA_STAT] |=3D DMA_STAT_DONE; - } } =20 static void esp_pci_dma_memory_read(void *opaque, uint8_t *buf, int len) @@ -363,24 +372,13 @@ static const VMStateDescription vmstate_esp_pci_scsi = =3D { } }; =20 -static void esp_pci_command_complete(SCSIRequest *req, size_t resid) -{ - ESPState *s =3D req->hba_private; - PCIESPState *pci =3D container_of(s, PCIESPState, esp); - - esp_command_complete(req, resid); - pci->dma_regs[DMA_WBC] =3D 0; - pci->dma_regs[DMA_STAT] |=3D DMA_STAT_DONE; - esp_pci_update_irq(pci); -} - static const struct SCSIBusInfo esp_pci_scsi_info =3D { .tcq =3D false, .max_target =3D ESP_MAX_DEVS, .max_lun =3D 7, =20 .transfer_data =3D esp_transfer_data, - .complete =3D esp_pci_command_complete, + .complete =3D esp_command_complete, .cancel =3D esp_request_cancelled, }; =20 --=20 2.39.2