From patchwork Fri Mar 29 09:09:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Damien Le Moal X-Patchwork-Id: 13610387 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id B84C1CD128D for ; Fri, 29 Mar 2024 09:10:37 +0000 (UTC) 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:References:In-Reply-To: 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: List-Owner; bh=Ep/ygYNk9abDArkdRuCBkd0EREdDGgtoJD/KDmmtjfw=; b=xJu08x6KAhQ4P6 8VGUaClbpeSw6Arv7G1KUGFBfJVnkeURGcTZIRsa1XLR5obBwnlVZ/teyrg0DAbgUkgeEVlzG3W8e LK8f+atTguVjHBb69zCAzKxD08/Fh98S1puxA2/CxG/y9G+cOT2AO3TRzQiWudK8KW0ON9/hXIlmj VWK9NKlOSdgEqV/m/WzYgdxXoAaH4Vuc0i7PEJjGeMixGnSCQfRehYp/Wx669EbC97UghG3LvK9nz +qd2g7xwdwhEjrIZYvdtJp4IaCcroomKmZ4PyvGbxkoj08t8U5FznVc2JzvCF1lzsAfxZYJi+v4QB 8slEo7XUGOpKGnDDqoAA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rq8Fq-0000000HQZ8-2Okc; Fri, 29 Mar 2024 09:10:30 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rq8Fa-0000000HQ9p-12gl for linux-rockchip@lists.infradead.org; Fri, 29 Mar 2024 09:10:17 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 054E261764; Fri, 29 Mar 2024 09:10:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A56C3C433F1; Fri, 29 Mar 2024 09:10:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711703413; bh=+TmInabN37SfEhMgyX/p7nVgLz3hbajUkBFvvCUgxJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=env7fnJMur239VcR6gPVXw7rC1BdzlLCS6Hjm+pdshs7w7u45zeiwvIgjhi/ZZF7F /DdgykUQRq1i+X+Pf9A+bn3+8Kqr3U0h8KOBBqB7k/Ebym/1/10uOX6JsIJg+xl95h 9bURXPPnxl1pRtORkL63Pw5S5e/OGE01PhQdDJMKmAU+CdYY69dhdKiHcF9sUHIR5T 3lSY2SYSB5ZJ5i4juakmw07PExxaTVms6OGuEu4jtetq3PfMwWK4+zLQod4nmOb4WM nfubqpPKqv10sdDvHreOhp/OZcjC01fPAZCC8PCxGUfa2BM576m+smnIOrOkkwySXl SEgUvvXLcg/RQ== From: Damien Le Moal To: Manivannan Sadhasivam , Kishon Vijay Abraham I , Shawn Lin , =?utf-8?q?Krzysztof_Wilczy=C5=84ski?= , Bjorn Helgaas , Heiko Stuebner , linux-pci@vger.kernel.org Cc: linux-rockchip@lists.infradead.org Subject: [PATCH 17/19] PCI: rockchip-ep: Improve link training Date: Fri, 29 Mar 2024 18:09:43 +0900 Message-ID: <20240329090945.1097609-18-dlemoal@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240329090945.1097609-1-dlemoal@kernel.org> References: <20240329090945.1097609-1-dlemoal@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240329_021014_564190_33E35953 X-CRM114-Status: GOOD ( 22.33 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org The Rockchip rk339 technical reference manual describe the endpoint mode link training process clearly and states that: Insure link training completion and success by observing link_st field in PCIe Client BASIC_STATUS1 register change to 2'b11. If both side support PCIe Gen2 speed, re-train can be Initiated by asserting the Retrain Link field in Link Control and Status Register. The software should insure the BASIC_STATUS0[negotiated_speed] changes to "1", that indicates re-train to Gen2 successfully. This procedure is very similar to what is done for the root-port mode in rockchip_pcie_host_init_port(). Implement this link training procedure for the endpoint mode as well. Given that the rk3399 SoC does not have an interrupt signaling link status changes, training is implemented as a delayed work which is rescheduled until the link training completes or the endpoint controller is stopped. The link training work is first scheduled in rockchip_pcie_ep_start() when the endpoint function is started. Link training completion is signaled to the function using pci_epc_linkup(). Accordingly, the linkup_notifier field of the rockchip pci_epc_features structure is changed to true. Signed-off-by: Damien Le Moal --- drivers/pci/controller/pcie-rockchip-ep.c | 79 ++++++++++++++++++++++- drivers/pci/controller/pcie-rockchip.h | 11 ++++ 2 files changed, 89 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c index c126da07bf0c..d8e56b4a5578 100644 --- a/drivers/pci/controller/pcie-rockchip-ep.c +++ b/drivers/pci/controller/pcie-rockchip-ep.c @@ -16,6 +16,8 @@ #include #include #include +#include +#include #include "pcie-rockchip.h" @@ -48,6 +50,7 @@ struct rockchip_pcie_ep { u64 irq_pci_addr; u8 irq_pci_fn; u8 irq_pending; + struct delayed_work link_training; }; static void rockchip_pcie_clear_ep_ob_atu(struct rockchip_pcie *rockchip, @@ -467,6 +470,8 @@ static int rockchip_pcie_ep_start(struct pci_epc *epc) PCIE_CLIENT_CONF_ENABLE, PCIE_CLIENT_CONFIG); + schedule_delayed_work(&ep->link_training, 0); + return 0; } @@ -475,6 +480,8 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc) struct rockchip_pcie_ep *ep = epc_get_drvdata(epc); struct rockchip_pcie *rockchip = &ep->rockchip; + cancel_delayed_work_sync(&ep->link_training); + /* Stop link training and disable configuration */ rockchip_pcie_write(rockchip, PCIE_CLIENT_CONF_DISABLE | @@ -482,8 +489,77 @@ static void rockchip_pcie_ep_stop(struct pci_epc *epc) PCIE_CLIENT_CONFIG); } +static void rockchip_pcie_ep_retrain_link(struct rockchip_pcie *rockchip) +{ + u32 status; + + status = rockchip_pcie_read(rockchip, PCIE_EP_CONFIG_LCS); + status |= PCI_EXP_LNKCTL_RL; + rockchip_pcie_write(rockchip, status, PCIE_EP_CONFIG_LCS); +} + +static bool rockchip_pcie_ep_link_up(struct rockchip_pcie *rockchip) +{ + u32 val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS1); + + return PCIE_LINK_UP(val); +} + +static void rockchip_pcie_ep_link_training(struct work_struct *work) +{ + struct rockchip_pcie_ep *ep = + container_of(work, struct rockchip_pcie_ep, link_training.work); + struct rockchip_pcie *rockchip = &ep->rockchip; + struct device *dev = rockchip->dev; + u32 val; + int ret; + + /* Enable Gen1 training and wait for its completion */ + ret = readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL, + val, PCIE_LINK_TRAINING_DONE(val), 50, + LINK_TRAIN_TIMEOUT); + if (ret) + goto again; + + /* Make sure that the link is up */ + ret = readl_poll_timeout(rockchip->apb_base + PCIE_CLIENT_BASIC_STATUS1, + val, PCIE_LINK_UP(val), 50, + LINK_TRAIN_TIMEOUT); + if (ret) + goto again; + + /* Check the current speed */ + val = rockchip_pcie_read(rockchip, PCIE_CORE_CTRL); + if (!PCIE_LINK_IS_GEN2(val) && rockchip->link_gen == 2) { + /* Enable retrain for gen2 */ + rockchip_pcie_ep_retrain_link(rockchip); + readl_poll_timeout(rockchip->apb_base + PCIE_CORE_CTRL, + val, PCIE_LINK_IS_GEN2(val), 50, + LINK_TRAIN_TIMEOUT); + } + + /* Check again that the link is up */ + if (!rockchip_pcie_ep_link_up(rockchip)) + goto again; + + val = rockchip_pcie_read(rockchip, PCIE_CLIENT_BASIC_STATUS0); + dev_info(dev, + "Link UP (Negociated speed: %sGT/s, width: x%lu)\n", + (val & PCIE_CLIENT_NEG_LINK_SPEED) ? "5" : "2.5", + ((val & PCIE_CLIENT_NEG_LINK_WIDTH_MASK) >> + PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT) << 1); + + /* Notify the function */ + pci_epc_linkup(ep->epc); + + return; + +again: + schedule_delayed_work(&ep->link_training, msecs_to_jiffies(5)); +} + static const struct pci_epc_features rockchip_pcie_epc_features = { - .linkup_notifier = false, + .linkup_notifier = true, .msi_capable = true, .msix_capable = false, .align = ROCKCHIP_PCIE_AT_SIZE_ALIGN, @@ -644,6 +720,7 @@ static int rockchip_pcie_ep_probe(struct platform_device *pdev) rockchip = &ep->rockchip; rockchip->is_rc = false; rockchip->dev = dev; + INIT_DELAYED_WORK(&ep->link_training, rockchip_pcie_ep_link_training); epc = devm_pci_epc_create(dev, &rockchip_pcie_epc_ops); if (IS_ERR(epc)) { diff --git a/drivers/pci/controller/pcie-rockchip.h b/drivers/pci/controller/pcie-rockchip.h index 0263f158ee8d..3963b7097a91 100644 --- a/drivers/pci/controller/pcie-rockchip.h +++ b/drivers/pci/controller/pcie-rockchip.h @@ -26,6 +26,7 @@ #define MAX_LANE_NUM 4 #define MAX_REGION_LIMIT 32 #define MIN_EP_APERTURE 28 +#define LINK_TRAIN_TIMEOUT (5000 * USEC_PER_MSEC) #define PCIE_CLIENT_BASE 0x0 #define PCIE_CLIENT_CONFIG (PCIE_CLIENT_BASE + 0x00) @@ -50,6 +51,10 @@ #define PCIE_CLIENT_DEBUG_LTSSM_MASK GENMASK(5, 0) #define PCIE_CLIENT_DEBUG_LTSSM_L1 0x18 #define PCIE_CLIENT_DEBUG_LTSSM_L2 0x19 +#define PCIE_CLIENT_BASIC_STATUS0 (PCIE_CLIENT_BASE + 0x44) +#define PCIE_CLIENT_NEG_LINK_WIDTH_MASK GENMASK(7, 6) +#define PCIE_CLIENT_NEG_LINK_WIDTH_SHIFT 6 +#define PCIE_CLIENT_NEG_LINK_SPEED BIT(5) #define PCIE_CLIENT_BASIC_STATUS1 (PCIE_CLIENT_BASE + 0x48) #define PCIE_CLIENT_LINK_STATUS_UP 0x00300000 #define PCIE_CLIENT_LINK_STATUS_MASK 0x00300000 @@ -87,6 +92,8 @@ #define PCIE_CORE_CTRL_MGMT_BASE 0x900000 #define PCIE_CORE_CTRL (PCIE_CORE_CTRL_MGMT_BASE + 0x000) +#define PCIE_CORE_PL_CONF_LS_MASK 0x00000001 +#define PCIE_CORE_PL_CONF_LS_READY 0x00000001 #define PCIE_CORE_PL_CONF_SPEED_5G 0x00000008 #define PCIE_CORE_PL_CONF_SPEED_MASK 0x00000018 #define PCIE_CORE_PL_CONF_LANE_MASK 0x00000006 @@ -144,6 +151,7 @@ #define PCIE_RC_CONFIG_BASE 0xa00000 #define PCIE_EP_CONFIG_BASE 0xa00000 #define PCIE_EP_CONFIG_DID_VID (PCIE_EP_CONFIG_BASE + 0x00) +#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0) #define PCIE_RC_CONFIG_RID_CCR (PCIE_RC_CONFIG_BASE + 0x08) #define PCIE_RC_CONFIG_DCR (PCIE_RC_CONFIG_BASE + 0xc4) #define PCIE_RC_CONFIG_DCR_CSPL_SHIFT 18 @@ -155,6 +163,7 @@ #define PCIE_RC_CONFIG_LINK_CAP (PCIE_RC_CONFIG_BASE + 0xcc) #define PCIE_RC_CONFIG_LINK_CAP_L0S BIT(10) #define PCIE_RC_CONFIG_LCS (PCIE_RC_CONFIG_BASE + 0xd0) +#define PCIE_EP_CONFIG_LCS (PCIE_EP_CONFIG_BASE + 0xd0) #define PCIE_RC_CONFIG_L1_SUBSTATE_CTRL2 (PCIE_RC_CONFIG_BASE + 0x90c) #define PCIE_RC_CONFIG_THP_CAP (PCIE_RC_CONFIG_BASE + 0x274) #define PCIE_RC_CONFIG_THP_CAP_NEXT_MASK GENMASK(31, 20) @@ -192,6 +201,8 @@ #define ROCKCHIP_VENDOR_ID 0x1d87 #define PCIE_LINK_IS_L2(x) \ (((x) & PCIE_CLIENT_DEBUG_LTSSM_MASK) == PCIE_CLIENT_DEBUG_LTSSM_L2) +#define PCIE_LINK_TRAINING_DONE(x) \ + (((x) & PCIE_CORE_PL_CONF_LS_MASK) == PCIE_CORE_PL_CONF_LS_READY) #define PCIE_LINK_UP(x) \ (((x) & PCIE_CLIENT_LINK_STATUS_MASK) == PCIE_CLIENT_LINK_STATUS_UP) #define PCIE_LINK_IS_GEN2(x) \