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 DBB10C433EF for ; Thu, 25 Nov 2021 12:50:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355219AbhKYMxZ (ORCPT ); Thu, 25 Nov 2021 07:53:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:45582 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353413AbhKYMvp (ORCPT ); Thu, 25 Nov 2021 07:51:45 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7750D61139; Thu, 25 Nov 2021 12:46:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1637844399; bh=8IVaDVY9hPRIGDZRDN90aFjLyHB9vSl+f8YJ0WtixNg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rEwyH3uNfHbBqv91vf66yCBCcd+vPBv2NFDtCdRxmaEbxzVZFKfzIBhUntF7oCDHs RWeiQYola42948pTu9MtHMtmCjjnbtIzLzOsc1DEbKlKyU59CSjNTfUFCCgk2MXs9v N+Gsu7p45MG2E56JNfAfKxQ8Ed2BM7MaQ0bd3oqmAEoWgIOuS8C9/oGEpXfVkbpNrM 82LYNbCfpkB+iMxy4atLGUUz1yhHeD7NkpLestOwtcg5+fBlRiI8kQkWtuDbXsd2Ww iWrUeHXCRyRqqowtQSyigEKU9rU7VVaT8hc5uYnmBKPMx3PW6AxPep/5c8rbaYvqlp gNeyoJIiHdjGQ== Received: by pali.im (Postfix) id 57DC467E; Thu, 25 Nov 2021 13:46:36 +0100 (CET) From: =?UTF-8?q?Pali=20Roh=C3=A1r?= To: Thomas Petazzoni , Lorenzo Pieralisi , Rob Herring , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Bjorn Helgaas , =?UTF-8?q?Marek=20Beh=C3=BAn?= Cc: linux-pci@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 06/15] PCI: mvebu: Fix support for bus mastering and PCI_COMMAND on emulated bridge Date: Thu, 25 Nov 2021 13:45:56 +0100 Message-Id: <20211125124605.25915-7-pali@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20211125124605.25915-1-pali@kernel.org> References: <20211125124605.25915-1-pali@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to PCI specifications bits [0:2] of Command Register, this should be by default disabled on reset. So explicitly disable these bits at early beginning of driver initialization. Also remove code which unconditionally enables all 3 bits and let kernel code (via pci_set_master() function) to handle bus mastering of PCI Bridge via emulated PCI_COMMAND on emulated bridge. Adjust existing functions mvebu_pcie_handle_iobase_change() and mvebu_pcie_handle_membase_change() to handle PCI_IO_BASE and PCI_MEM_BASE registers correctly even when bus mastering on emulated bridge is disabled. Signed-off-by: Pali Rohár Cc: stable@vger.kernel.org --- drivers/pci/controller/pci-mvebu.c | 52 ++++++++++++++++++------------ 1 file changed, 32 insertions(+), 20 deletions(-) diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c index a3df352d440e..32694763e930 100644 --- a/drivers/pci/controller/pci-mvebu.c +++ b/drivers/pci/controller/pci-mvebu.c @@ -226,16 +226,14 @@ static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port) { u32 cmd, mask; - /* Point PCIe unit MBUS decode windows to DRAM space. */ - mvebu_pcie_setup_wins(port); - - /* Master + slave enable. */ + /* Disable Root Bridge I/O space, memory space and bus mastering. */ cmd = mvebu_readl(port, PCIE_CMD_OFF); - cmd |= PCI_COMMAND_IO; - cmd |= PCI_COMMAND_MEMORY; - cmd |= PCI_COMMAND_MASTER; + cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER); mvebu_writel(port, cmd, PCIE_CMD_OFF); + /* Point PCIe unit MBUS decode windows to DRAM space. */ + mvebu_pcie_setup_wins(port); + /* Enable interrupt lines A-D. */ mask = mvebu_readl(port, PCIE_MASK_OFF); mask |= PCIE_MASK_ENABLE_INTS; @@ -385,8 +383,7 @@ static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port) /* Are the new iobase/iolimit values invalid? */ if (conf->iolimit < conf->iobase || - conf->iolimitupper < conf->iobaseupper || - !(conf->command & PCI_COMMAND_IO)) { + conf->iolimitupper < conf->iobaseupper) { mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired, &port->iowin); return; @@ -423,8 +420,7 @@ static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port) struct pci_bridge_emul_conf *conf = &port->bridge.conf; /* Are the new membase/memlimit values invalid? */ - if (conf->memlimit < conf->membase || - !(conf->command & PCI_COMMAND_MEMORY)) { + if (conf->memlimit < conf->membase) { mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired, &port->memwin); return; @@ -444,6 +440,24 @@ static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port) &port->memwin); } +static pci_bridge_emul_read_status_t +mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge, + int reg, u32 *value) +{ + struct mvebu_pcie_port *port = bridge->data; + + switch (reg) { + case PCI_COMMAND: + *value = mvebu_readl(port, PCIE_CMD_OFF); + break; + + default: + return PCI_BRIDGE_EMUL_NOT_HANDLED; + } + + return PCI_BRIDGE_EMUL_HANDLED; +} + static pci_bridge_emul_read_status_t mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge, int reg, u32 *value) @@ -498,17 +512,14 @@ mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge, switch (reg) { case PCI_COMMAND: - { - if (!mvebu_has_ioport(port)) - conf->command &= ~PCI_COMMAND_IO; - - if ((old ^ new) & PCI_COMMAND_IO) - mvebu_pcie_handle_iobase_change(port); - if ((old ^ new) & PCI_COMMAND_MEMORY) - mvebu_pcie_handle_membase_change(port); + if (!mvebu_has_ioport(port)) { + conf->command = cpu_to_le16( + le16_to_cpu(conf->command) & ~PCI_COMMAND_IO); + new &= ~PCI_COMMAND_IO; + } + mvebu_writel(port, new, PCIE_CMD_OFF); break; - } case PCI_IO_BASE: /* @@ -575,6 +586,7 @@ mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge, } static struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = { + .read_base = mvebu_pci_bridge_emul_base_conf_read, .write_base = mvebu_pci_bridge_emul_base_conf_write, .read_pcie = mvebu_pci_bridge_emul_pcie_conf_read, .write_pcie = mvebu_pci_bridge_emul_pcie_conf_write, -- 2.20.1