From patchwork Wed Oct 4 08:37:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Cave-Ayland X-Patchwork-Id: 1843081 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=kEXvufS7; 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 4S0p5y6vv7z1ypx for ; Wed, 4 Oct 2023 19:39:50 +1100 (AEDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qnxP6-0003xx-4Y; Wed, 04 Oct 2023 04:38:48 -0400 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 1qnxP4-0003xW-Si for qemu-devel@nongnu.org; Wed, 04 Oct 2023 04:38:46 -0400 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 1qnxP3-0007bI-Aj for qemu-devel@nongnu.org; Wed, 04 Oct 2023 04:38:46 -0400 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=gZ86OMPpMlnB3D4ENs44jqarXK1astQH1B1zhzFrNbM=; b=kEXvufS79XOYWgdD9NBRlQHiCt tKZl4U5H1mdMAlDViP9N1FnimLyw9qQeLIQH1EeVS8gpOE7t7QJp61rXCNAgA0DTTS4r4TN3HoJMJ mrZXtN62JeFux4mQN0SvUMxTFot3mblP4PAuMRG+ddHAsBMr52IyxyOyR+ROjy0/jgXpSg0gPQipE vXFk7RepJK57UQmvVCA2jxmt+hibITjaUJrzXw5DmlE3n56gcjttQy+rff5sdUr432yieailhF1vN M25PppBavISg+e8G/TRSbID4QaRfUWdHPvpHY0MqlFxsdahZfJNYiW/JVSZlNMuk8U1Cv9zkLFX+a 1qqSN6hx+S+dQw6dE0ZXFWaLh4CFwiAxAgnqD7FCxe4yjSGgHir/N3P1NPOTa7EamscNY79VUxSYN rzG0cidDm845fzjjXbDkvhahK4Nxz64684EZgD554Q7uoFXXq5Z01zBvVN5Pa1lpqzPuPxAHCL86t ckoU6Y5B53rWNE9NR54AzTKaHE5HiWlRag7V+OgOxXOQylAR7TMqLBDhqlCKucETpm3FJv5R2TWhP YE5bUuSrPMeZ6Pbeu1kWMYk0XNeiN1dtSENbB3RID1xbpk3rgYV5LKe9BsJ6x45UiREoj5idOrvXI J86CXSlq48iR7Cg2Bq4sAbSmjOfpNmvLnZI0zn6K0=; Received: from host86-159-123-68.range86-159.btcentralplus.com ([86.159.123.68] 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 1qnxOo-0006za-GD; Wed, 04 Oct 2023 09:38:34 +0100 From: Mark Cave-Ayland To: laurent@vivier.eu, qemu-devel@nongnu.org Date: Wed, 4 Oct 2023 09:37:54 +0100 Message-Id: <20231004083806.757242-9-mark.cave-ayland@ilande.co.uk> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231004083806.757242-1-mark.cave-ayland@ilande.co.uk> References: <20231004083806.757242-1-mark.cave-ayland@ilande.co.uk> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 86.159.123.68 X-SA-Exim-Mail-From: mark.cave-ayland@ilande.co.uk Subject: [PATCH v4 08/20] asc: generate silence if FIFO empty but engine still running 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 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 MacOS (un)helpfully leaves the FIFO engine running even when all the samples have been written to the hardware, and expects the FIFO status flags and IRQ to be updated continuously. There is an additional problem in that not all audio backends guarantee an all-zero output when there is no FIFO data available, in particular the Windows dsound backend which re-uses its internal circular buffer causing the last played sound to loop indefinitely. Whilst this is effectively a bug in the Windows dsound backend, work around it for now using a simple heuristic: if the FIFO remains empty for half a cycle (~23ms) then continuously fill the generated buffer with empty silence. Signed-off-by: Mark Cave-Ayland Reviewed-by: Laurent Vivier --- hw/audio/asc.c | 19 +++++++++++++++++++ include/hw/audio/asc.h | 2 ++ 2 files changed, 21 insertions(+) diff --git a/hw/audio/asc.c b/hw/audio/asc.c index 9084708eaf..0f36b4ce9b 100644 --- a/hw/audio/asc.c +++ b/hw/audio/asc.c @@ -341,6 +341,21 @@ static void asc_out_cb(void *opaque, int free_b) } if (!generated) { + /* Workaround for audio underflow bug on Windows dsound backend */ + int64_t now = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL); + int silent_samples = muldiv64(now - s->fifo_empty_ns, + NANOSECONDS_PER_SECOND, ASC_FREQ); + + if (silent_samples > ASC_FIFO_CYCLE_TIME / 2) { + /* + * No new FIFO data within half a cycle time (~23ms) so fill the + * entire available buffer with silence. This prevents an issue + * with the Windows dsound backend whereby the sound appears to + * loop because the FIFO has run out of data, and the driver + * reuses the stale content in its circular audio buffer. + */ + AUD_write(s->voice, s->silentbuf, samples << s->shift); + } return; } @@ -618,6 +633,7 @@ static void asc_unrealize(DeviceState *dev) ASCState *s = ASC(dev); g_free(s->mixbuf); + g_free(s->silentbuf); AUD_remove_card(&s->card); } @@ -642,6 +658,9 @@ static void asc_realize(DeviceState *dev, Error **errp) s->samples = AUD_get_buffer_size_out(s->voice) >> s->shift; s->mixbuf = g_malloc0(s->samples << s->shift); + s->silentbuf = g_malloc0(s->samples << s->shift); + memset(s->silentbuf, 0x80, s->samples << s->shift); + /* Add easc registers if required */ if (s->type == ASC_TYPE_EASC) { memory_region_add_subregion(&s->asc, ASC_EXTREG_OFFSET, diff --git a/include/hw/audio/asc.h b/include/hw/audio/asc.h index d9412815c3..4741f92c46 100644 --- a/include/hw/audio/asc.h +++ b/include/hw/audio/asc.h @@ -68,6 +68,8 @@ struct ASCState { int samples; int shift; + uint8_t *silentbuf; + /* Time when we were last able to generate samples */ int64_t fifo_empty_ns;