From patchwork Wed Jan 13 11:40:00 2021 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: 12016579 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 X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2B75AC433E0 for ; Wed, 13 Jan 2021 11:42:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9ECA233F7 for ; Wed, 13 Jan 2021 11:42:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726732AbhAMLl7 (ORCPT ); Wed, 13 Jan 2021 06:41:59 -0500 Received: from mailgw01.mediatek.com ([210.61.82.183]:60713 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725998AbhAMLl6 (ORCPT ); Wed, 13 Jan 2021 06:41:58 -0500 X-UUID: 2d0d86c6fcac48a0877b24c1d8e95cc3-20210113 X-UUID: 2d0d86c6fcac48a0877b24c1d8e95cc3-20210113 Received: from mtkexhb01.mediatek.inc [(172.21.101.102)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 55072910; Wed, 13 Jan 2021 19:41:01 +0800 Received: from mtkcas10.mediatek.inc (172.21.101.39) by mtkmbs05n2.mediatek.inc (172.21.101.140) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 13 Jan 2021 19:40:59 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkcas10.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Wed, 13 Jan 2021 19:40:58 +0800 From: Jianjun Wang To: Bjorn Helgaas , Rob Herring , , Lorenzo Pieralisi , Ryder Lee CC: Philipp Zabel , Matthias Brugger , , , , , , Sj Huang , Jianjun Wang , , , , , , , Subject: [v7,6/7] PCI: mediatek-gen3: Add system PM support Date: Wed, 13 Jan 2021 19:40:00 +0800 Message-ID: <20210113114001.5804-7-jianjun.wang@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20210113114001.5804-1-jianjun.wang@mediatek.com> References: <20210113114001.5804-1-jianjun.wang@mediatek.com> MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add suspend_noirq and resume_noirq callback functions to implement PM system suspend hooks for MediaTek Gen3 PCIe controller. When system suspend, trigger the PCIe link to L2 state and pull down the PERST# pin, gating the clocks of MAC layer and power off the physical layer for the sake of power saving. When system resum, the PCIe link should be re-established and the related control register values should be restored. Signed-off-by: Jianjun Wang Acked-by: Ryder Lee --- drivers/pci/controller/pcie-mediatek-gen3.c | 78 +++++++++++++++++++++ 1 file changed, 78 insertions(+) diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c index 152820f28da1..ac6c43cea575 100644 --- a/drivers/pci/controller/pcie-mediatek-gen3.c +++ b/drivers/pci/controller/pcie-mediatek-gen3.c @@ -49,6 +49,9 @@ #define PCIE_PE_RSTB BIT(3) #define PCIE_LTSSM_STATUS_REG 0x150 +#define PCIE_LTSSM_STATE_MASK GENMASK(28, 24) +#define PCIE_LTSSM_STATE(val) ((val & PCIE_LTSSM_STATE_MASK) >> 24) +#define PCIE_LTSSM_STATE_L2_IDLE 0x14 #define PCIE_LINK_STATUS_REG 0x154 #define PCIE_PORT_LINKUP BIT(8) @@ -76,6 +79,9 @@ #define PCIE_MSI_SET_ADDR_HI_BASE 0xc80 #define PCIE_MSI_SET_ADDR_HI_OFFSET 0x04 +#define PCIE_ICMD_PM_REG 0x198 +#define PCIE_TURN_OFF_LINK BIT(4) + #define PCIE_TRANS_TABLE_BASE_REG 0x800 #define PCIE_ATR_SRC_ADDR_MSB_OFFSET 0x4 #define PCIE_ATR_TRSL_ADDR_LSB_OFFSET 0x8 @@ -869,6 +875,77 @@ static int mtk_pcie_remove(struct platform_device *pdev) return 0; } +static int __maybe_unused mtk_pcie_turn_off_link(struct mtk_pcie_port *port) +{ + u32 val; + + val = readl_relaxed(port->base + PCIE_ICMD_PM_REG); + val |= PCIE_TURN_OFF_LINK; + writel_relaxed(val, port->base + PCIE_ICMD_PM_REG); + + /* Check the link is L2 */ + return readl_poll_timeout(port->base + PCIE_LTSSM_STATUS_REG, val, + (PCIE_LTSSM_STATE(val) == + PCIE_LTSSM_STATE_L2_IDLE), 20, + 50 * USEC_PER_MSEC); +} + +static int __maybe_unused mtk_pcie_suspend_noirq(struct device *dev) +{ + struct mtk_pcie_port *port = dev_get_drvdata(dev); + int err; + u32 val; + + /* Trigger link to L2 state */ + err = mtk_pcie_turn_off_link(port); + if (err) { + dev_err(port->dev, "can not enter L2 state\n"); + return err; + } + + /* Pull down the PERST# pin */ + val = readl_relaxed(port->base + PCIE_RST_CTRL_REG); + val |= PCIE_PE_RSTB; + writel_relaxed(val, port->base + PCIE_RST_CTRL_REG); + + dev_dbg(port->dev, "enter L2 state success"); + + clk_bulk_disable_unprepare(port->num_clks, port->clks); + + phy_power_off(port->phy); + + return 0; +} + +static int __maybe_unused mtk_pcie_resume_noirq(struct device *dev) +{ + struct mtk_pcie_port *port = dev_get_drvdata(dev); + int err; + + phy_power_on(port->phy); + + err = clk_bulk_prepare_enable(port->num_clks, port->clks); + if (err) { + dev_dbg(dev, "failed to enable PCIe clocks\n"); + return err; + } + + err = mtk_pcie_startup_port(port); + if (err) { + dev_err(port->dev, "resume failed\n"); + return err; + } + + dev_dbg(port->dev, "resume done\n"); + + return 0; +} + +static const struct dev_pm_ops mtk_pcie_pm_ops = { + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_pcie_suspend_noirq, + mtk_pcie_resume_noirq) +}; + static const struct of_device_id mtk_pcie_of_match[] = { { .compatible = "mediatek,mt8192-pcie" }, {}, @@ -880,6 +957,7 @@ static struct platform_driver mtk_pcie_driver = { .driver = { .name = "mtk-pcie", .of_match_table = mtk_pcie_of_match, + .pm = &mtk_pcie_pm_ops, }, };