From patchwork Tue Mar 29 03:07:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?Smlhbmp1biBXYW5nICjnjovlu7rlhpsp?= X-Patchwork-Id: 12794412 X-Patchwork-Delegate: lorenzo.pieralisi@arm.com 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 63DB8C433EF for ; Tue, 29 Mar 2022 03:07:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230260AbiC2DJK (ORCPT ); Mon, 28 Mar 2022 23:09:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52412 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230050AbiC2DJI (ORCPT ); Mon, 28 Mar 2022 23:09:08 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F24FD23D585; Mon, 28 Mar 2022 20:07:24 -0700 (PDT) X-UUID: 4ec0f3a111b64b12bd33f018795d3e71-20220329 X-UUID: 4ec0f3a111b64b12bd33f018795d3e71-20220329 Received: from mtkmbs10n2.mediatek.inc [(172.21.101.183)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1172233676; Tue, 29 Mar 2022 11:07:20 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Tue, 29 Mar 2022 11:07:19 +0800 Received: from localhost.localdomain (10.17.3.154) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Tue, 29 Mar 2022 11:07:16 +0800 From: Jianjun Wang To: Ryder Lee , Lorenzo Pieralisi , Bjorn Helgaas CC: AngeloGioacchino Del Regno , Jianjun Wang , Rob Herring , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Matthias Brugger , , , , , , , , Subject: [PATCH v2] PCI: mediatek-gen3: Print LTSSM state when PCIe link down Date: Tue, 29 Mar 2022 11:07:15 +0800 Message-ID: <20220329030715.7975-1-jianjun.wang@mediatek.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Print current LTSSM state when PCIe link down instead of the register value, make it easier to get the link status. Signed-off-by: Jianjun Wang Reviewed-by: AngeloGioacchino Del Regno --- Changes in v2: Print both of the register value and the LTSSM state. --- drivers/pci/controller/pcie-mediatek-gen3.c | 41 ++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 6745076a02b9..c24e03c198b7 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -153,6 +153,37 @@ struct mtk_gen3_pcie { DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM); }; +/* LTSSM state in PCIE_LTSSM_STATUS_REG bit[28:24] */ +static const char *const ltssm_str[] = { + "detect.quiet", /* 0x00 */ + "detect.active", /* 0x01 */ + "polling.active", /* 0x02 */ + "polling.compliance", /* 0x03 */ + "polling.configuration", /* 0x04 */ + "config.linkwidthstart", /* 0x05 */ + "config.linkwidthaccept", /* 0x06 */ + "config.lanenumwait", /* 0x07 */ + "config.lanenumaccept", /* 0x08 */ + "config.complete", /* 0x09 */ + "config.idle", /* 0x0A */ + "recovery.receiverlock", /* 0x0B */ + "recovery.equalization", /* 0x0C */ + "recovery.speed", /* 0x0D */ + "recovery.receiverconfig", /* 0x0E */ + "recovery.idle", /* 0x0F */ + "L0", /* 0x10 */ + "L0s", /* 0x11 */ + "L1.entry", /* 0x12 */ + "L1.idle", /* 0x13 */ + "L2.idle", /* 0x14 */ + "L2.transmitwake", /* 0x15 */ + "disable", /* 0x16 */ + "loopback.entry", /* 0x17 */ + "loopback.active", /* 0x18 */ + "loopback.exit", /* 0x19 */ + "hotreset", /* 0x1A */ +}; + /** * mtk_pcie_config_tlp_header() - Configure a configuration TLP header * @bus: PCI bus to query @@ -327,8 +358,16 @@ static int mtk_pcie_startup_port(struct mtk_gen3_pcie *pcie) !!(val & PCIE_PORT_LINKUP), 20, PCI_PM_D3COLD_WAIT * USEC_PER_MSEC); if (err) { + const char *ltssm_state; + int ltssm_index; + val = readl_relaxed(pcie->base + PCIE_LTSSM_STATUS_REG); - dev_err(pcie->dev, "PCIe link down, ltssm reg val: %#x\n", val); + ltssm_index = PCIE_LTSSM_STATE(val); + ltssm_state = ltssm_index >= ARRAY_SIZE(ltssm_str) ? + "Unknown state" : ltssm_str[ltssm_index]; + dev_err(pcie->dev, + "PCIe link down, current ltssm state: %s (%#x)\n", + ltssm_state, val); return err; }