From patchwork Fri Mar 25 09:38:27 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Pali_Roh=C3=A1r?= X-Patchwork-Id: 12791389 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 E24B3C433F5 for ; Fri, 25 Mar 2022 09:40:32 +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=l6VLxMSajylS3lLwtGVB419bC+DcuAvYibs9GjEDDvY=; b=XvGCM8X2gwDb6v +sInQOl+flWgK8x97mq5ou1Y2J+PhY6HonnYjjbGBjZtESY9ETn4o6bIowv38sB8xUzAHNWv2uPGQ y+tbZukgxPSURydvKf99hR0sl2w+e9jKJW/qolMPjBQEyajLbxwdwECjP8dqSuMYVy1bmkbYNQ+pS nHBkbbCPHxcxouTaSVcVeR4FXfCzJR+BBr6YNgiqh47I7StkVrx0n4B9vhONKgDLqV5XW0v/RLxEU 20pVT+Q5nr2h/u8IAmRnTfKp+s+1sLcx7SFJTsOnqDWH6G9uttH92en/gnmhy3ag+nYFOKTDmpRxV g0rM/B/JRq1LeoznXAqA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXgPn-001YIF-N8; Fri, 25 Mar 2022 09:39:27 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nXgPE-001Y6U-AP for linux-arm-kernel@lists.infradead.org; Fri, 25 Mar 2022 09:38:55 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id CA74760F04; Fri, 25 Mar 2022 09:38:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4BD0FC340F3; Fri, 25 Mar 2022 09:38:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648201131; bh=5YHL3Hjh0AaP8CgfCJ3QGpsdMmryF5kIFHovdhn9HfY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OiM4yd6tg6q6H5STDROUzynP0iPHUdSSKJb30alpn6LEUf3nLBFkXlM5elNtTxlv3 fX6+Ca+3H9QUZI0fIjYQqWiGsMXCsldd/6QUzIeZ6UmTvHneTTQ0fxZed1hqQldnlC dq7BlOuBkAS/Jdgo+Y58itGrGZR2T6s9R57mkfH4LskVMJ41ZN++tG2V7LV2/19Y2g xknI9HE4WEXPzsbz5McixT0Df5PkrdGZcXqqgoWU6dRH4zMqj+7eyCkzoU44vjHxxL gi6hAkP1St1+4Mlz+6iNZXTOzatgZs0li0Pu7TQ3t6wB/GKKigbw+FuyJqxYHzEsNy Dz+i1xaxkVb6Q== Received: by pali.im (Postfix) id 050147DD; Fri, 25 Mar 2022 10:38:51 +0100 (CET) From: =?utf-8?q?Pali_Roh=C3=A1r?= To: Lorenzo Pieralisi , Bjorn Helgaas , Rob Herring , Andrew Lunn , Thomas Petazzoni , =?utf-8?q?Krzysztof_Wilczy?= =?utf-8?q?=C5=84ski?= , =?utf-8?q?Marek_Beh=C3=BAn?= , Russell King Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 4/4] PCI: mvebu: Add support for sending Set_Slot_Power_Limit message Date: Fri, 25 Mar 2022 10:38:27 +0100 Message-Id: <20220325093827.4983-5-pali@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20220325093827.4983-1-pali@kernel.org> References: <20220325093827.4983-1-pali@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220325_023852_468775_58FCA7CE X-CRM114-Status: GOOD ( 25.21 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org If DT supplies the 'slot-power-limit-milliwatt' property, program the value in the Slot Power Limit in the Slot Capabilities register and program the Root Port to send a Set_Slot_Power_Limit Message when the Link transitions to DL_Up. Signed-off-by: Pali Rohár Reviewed-by: Rob Herring --- Changes in v2: * Fix handling of slot power limit with scale x1.0 (0x00 value) * Use FIELD_PREP instead of _SHIFT macros * Changed commit message to Bjorn's suggestion * Changed comments in the code to match PCIe spec * Preserve user settings of PCI_EXP_SLTCTL_ASPL_DISABLE bit --- drivers/pci/controller/pci-mvebu.c | 96 ++++++++++++++++++++++++++++-- 1 file changed, 91 insertions(+), 5 deletions(-) diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index a75d2b9196f9..26ae7c29fece 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include #include @@ -66,6 +67,12 @@ #define PCIE_STAT_BUS 0xff00 #define PCIE_STAT_DEV 0x1f0000 #define PCIE_STAT_LINK_DOWN BIT(0) +#define PCIE_SSPL_OFF 0x1a0c +#define PCIE_SSPL_VALUE_SHIFT 0 +#define PCIE_SSPL_VALUE_MASK GENMASK(7, 0) +#define PCIE_SSPL_SCALE_SHIFT 8 +#define PCIE_SSPL_SCALE_MASK GENMASK(9, 8) +#define PCIE_SSPL_ENABLE BIT(16) #define PCIE_RC_RTSTA 0x1a14 #define PCIE_DEBUG_CTRL 0x1a60 #define PCIE_DEBUG_SOFT_RESET BIT(20) @@ -111,6 +118,8 @@ struct mvebu_pcie_port { struct mvebu_pcie_window iowin; u32 saved_pcie_stat; struct resource regs; + u8 slot_power_limit_value; + u8 slot_power_limit_scale; struct irq_domain *intx_irq_domain; raw_spinlock_t irq_lock; int intx_irq; @@ -239,7 +248,7 @@ static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port) static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) { - u32 ctrl, lnkcap, cmd, dev_rev, unmask; + u32 ctrl, lnkcap, cmd, dev_rev, unmask, sspl; /* Setup PCIe controller to Root Complex mode. */ ctrl = mvebu_readl(port, PCIE_CTRL_OFF); @@ -292,6 +301,20 @@ static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) /* Point PCIe unit MBUS decode windows to DRAM space. */ mvebu_pcie_setup_wins(port); + /* + * Program Root Port to automatically send Set_Slot_Power_Limit + * PCIe Message when changing status from Dl_Down to Dl_Up and valid + * slot power limit was specified. + */ + sspl = mvebu_readl(port, PCIE_SSPL_OFF); + sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE); + if (port->slot_power_limit_value) { + sspl |= port->slot_power_limit_value << PCIE_SSPL_VALUE_SHIFT; + sspl |= port->slot_power_limit_scale << PCIE_SSPL_SCALE_SHIFT; + sspl |= PCIE_SSPL_ENABLE; + } + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + /* Mask all interrupt sources. */ mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF); @@ -628,9 +651,23 @@ mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, (PCI_EXP_LNKSTA_DLLLA << 16) : 0); break; - case PCI_EXP_SLTCTL: - *value = PCI_EXP_SLTSTA_PDS << 16; + case PCI_EXP_SLTCTL: { + u16 slotsta = le16_to_cpu(bridge->pcie_conf.slotsta); + u32 val = 0; + /* + * When slot power limit was not specified in DT then + * ASPL_DISABLE bit is stored only in emulated config space. + * Otherwise reflect status of PCIE_SSPL_ENABLE bit in HW. + */ + if (!port->slot_power_limit_value) + val |= slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE; + else if (!(mvebu_readl(port, PCIE_SSPL_OFF) & PCIE_SSPL_ENABLE)) + val |= PCI_EXP_SLTCTL_ASPL_DISABLE; + /* This callback is 32-bit and in high bits is slot status. */ + val |= slotsta << 16; + *value = val; break; + } case PCI_EXP_RTSTA: *value = mvebu_readl(port, PCIE_RC_RTSTA); @@ -774,6 +811,22 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL); break; + case PCI_EXP_SLTCTL: + /* + * Allow to change PCIE_SSPL_ENABLE bit only when slot power + * limit was specified in DT and configured into HW. + */ + if ((mask & PCI_EXP_SLTCTL_ASPL_DISABLE) && + port->slot_power_limit_value) { + u32 sspl = mvebu_readl(port, PCIE_SSPL_OFF); + if (new & PCI_EXP_SLTCTL_ASPL_DISABLE) + sspl &= ~PCIE_SSPL_ENABLE; + else + sspl |= PCIE_SSPL_ENABLE; + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + } + break; + case PCI_EXP_RTSTA: /* * PME Status bit in Root Status Register (PCIE_RC_RTSTA) @@ -868,8 +921,26 @@ static int mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port) /* * Older mvebu hardware provides PCIe Capability structure only in * version 1. New hardware provides it in version 2. + * Enable slot support which is emulated. */ - bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver); + bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver | PCI_EXP_FLAGS_SLOT); + + /* + * Set Presence Detect State bit permanently as there is no support for + * unplugging PCIe card from the slot. Assume that PCIe card is always + * connected in slot. + * + * Set physical slot number to port+1 as mvebu ports are indexed from + * zero and zero value is reserved for ports within the same silicon + * as Root Port which is not mvebu case. + * + * Also set correct slot power limit. + */ + bridge->pcie_conf.slotcap = cpu_to_le32( + FIELD_PREP(PCI_EXP_SLTCAP_SPLV, port->slot_power_limit_value) | + FIELD_PREP(PCI_EXP_SLTCAP_SPLS, port->slot_power_limit_scale) | + FIELD_PREP(PCI_EXP_SLTCAP_PSN, port->port+1)); + bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS); bridge->subsystem_vendor_id = ssdev_id & 0xffff; bridge->subsystem_id = ssdev_id >> 16; @@ -1191,6 +1262,7 @@ static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie, { struct device *dev = &pcie->pdev->dev; enum of_gpio_flags flags; + u32 slot_power_limit; int reset_gpio, ret; u32 num_lanes; @@ -1291,6 +1363,15 @@ static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie, port->reset_gpio = gpio_to_desc(reset_gpio); } + slot_power_limit = of_pci_get_slot_power_limit(child, + &port->slot_power_limit_value, + &port->slot_power_limit_scale); + if (slot_power_limit) + dev_info(dev, "%s: Slot power limit %u.%uW\n", + port->name, + slot_power_limit / 1000, + (slot_power_limit / 100) % 10); + port->clk = of_clk_get_by_name(child, NULL); if (IS_ERR(port->clk)) { dev_err(dev, "%s: cannot get clock\n", port->name); @@ -1587,7 +1668,7 @@ static int mvebu_pcie_remove(struct platform_device *pdev) { struct mvebu_pcie *pcie = platform_get_drvdata(pdev); struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie); - u32 cmd; + u32 cmd, sspl; int i; /* Remove PCI bus with all devices. */ @@ -1624,6 +1705,11 @@ static int mvebu_pcie_remove(struct platform_device *pdev) /* Free config space for emulated root bridge. */ pci_bridge_emul_cleanup(&port->bridge); + /* Disable sending Set_Slot_Power_Limit PCIe Message. */ + sspl = mvebu_readl(port, PCIE_SSPL_OFF); + sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE); + mvebu_writel(port, sspl, PCIE_SSPL_OFF); + /* Disable and clear BARs and windows. */ mvebu_pcie_disable_wins(port);