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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43657C433EF for ; Wed, 17 Nov 2021 16:16:38 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1054261BE1 for ; Wed, 17 Nov 2021 16:16:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 1054261BE1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:Cc :To:From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=2pffT6kY/SgjVq+nnBBrNlpJwmsXutn58Bwz6GvZ0Ho=; b=Ov7roYOsNIjcOA r+9OIO/Bz2wPNZNj5iH3slhwozJmlhlMQXHKVJ3loYJa3UFVZiqcNVdWv3Vtz34UGEVLzmRSyVoOK REQTBvTv3yAq62FhMykwk8btCRdq+34BjrjO7j7+synroJiMhygrnixTpApEK9zZg56XdOa0TufUv MQ16MO+jpGEpWsW/OkHWA5fZTEzN70D5jWcZnRiHhGSvULNPr9lXHonYTxErWdKdNMBHm387soufD xiNTm7yUYZzkkqPNFpCLqjC0zFQYz2ENNDC+SDcj0TPLhZwHzTn5xrwvYzSsy00ssPXRpsQMiXb9/ JcShY0zPoUUj7YN9rtOw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mnNaE-005hBn-7C; Wed, 17 Nov 2021 16:14:50 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mnNMs-005bEu-J2 for linux-arm-kernel@lists.infradead.org; Wed, 17 Nov 2021 16:01:05 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 50F5E61B48; Wed, 17 Nov 2021 16:01:02 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=hot-poop.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mnNMq-0067Me-4W; Wed, 17 Nov 2021 16:01:00 +0000 From: Marc Zyngier To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org Cc: kernel-team@android.com, Alyssa Rosenzweig , Lorenzo Pieralisi , Bjorn Helgaas Subject: [PATCH] PCI: apple: Reset the port for 100ms on probe Date: Wed, 17 Nov 2021 16:00:53 +0000 Message-Id: <20211117160053.232158-1-maz@kernel.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, kernel-team@android.com, alyssa@rosenzweig.io, lorenzo.pieralisi@arm.com, bhelgaas@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211117_080104_605078_8C52B40B X-CRM114-Status: GOOD ( 14.33 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org While the Apple PCIe driver works correctly when directly booted from the firmware, it fails to initialise when the kernel is booted from a bootloader using PCIe such as u-boot. That's beacuse we're missing a proper reset of the port (we only clear the reset, but never assert it). Bring the port back to life by wiggling the #PERST pin for 100ms (as per the spec). Fixes: 1e33888fbe44 ("PCI: apple: Add initial hardware bring-up") Signed-off-by: Marc Zyngier Cc: Alyssa Rosenzweig Cc: Lorenzo Pieralisi Cc: Bjorn Helgaas --- drivers/pci/controller/pcie-apple.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c index 1bf4d75b61be..bbea5f6e0a68 100644 --- a/drivers/pci/controller/pcie-apple.c +++ b/drivers/pci/controller/pcie-apple.c @@ -543,6 +543,9 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie, if (ret < 0) return ret; + /* Hold #PERST for 100ms as per the spec */ + gpiod_set_value(reset, 0); + msleep(100); rmw_set(PORT_PERST_OFF, port->base + PORT_PERST); gpiod_set_value(reset, 1); -- 2.30.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel