linux-kernel - [PATCH v2 4/5] PCI: designware: Add disable IO support

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <1426515635-9466-5-git-send-email-gabriel.fernandez@linaro.org>
Date:	Mon, 16 Mar 2015 15:20:34 +0100
From:	Gabriel FERNANDEZ <gabriel.fernandez@...com>
To:	Rob Herring <robh+dt@...nel.org>, Pawel Moll <pawel.moll@....com>,
	Mark Rutland <mark.rutland@....com>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Kumar Gala <galak@...eaurora.org>,
	Srinivas Kandagatla <srinivas.kandagatla@...il.com>,
	Maxime Coquelin <maxime.coquelin@...com>,
	Patrice Chotard <patrice.chotard@...com>,
	Russell King <linux@....linux.org.uk>,
	Bjorn Helgaas <bhelgaas@...gle.com>,
	Mohit Kumar <mohit.kumar@...com>,
	Jingoo Han <jg1.han@...sung.com>,
	Lucas Stach <l.stach@...gutronix.de>,
	Fabrice Gasnier <fabrice.gasnier@...com>,
	Kishon Vijay Abraham I <kishon@...com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	" David S. Miller" <davem@...emloft.net>,
	Greg KH <gregkh@...uxfoundation.org>,
	Mauro Carvalho Chehab <mchehab@....samsung.com>,
	Joe Perches <joe@...ches.com>, Tejun Heo <tj@...nel.org>,
	Arnd Bergmann <arnd@...db.de>,
	Viresh Kumar <viresh.kumar@...aro.org>,
	Thierry Reding <treding@...dia.com>,
	Phil Edworthy <phil.edworthy@...esas.com>,
	Minghuan Lian <Minghuan.Lian@...escale.com>,
	Tanmay Inamdar <tinamdar@....com>, <m-karicheri2@...com>,
	Sachin Kamat <sachin.kamat@...sung.com>,
	Andrew Lunn <andrew@...n.ch>, Liviu Dudau <liviu.dudau@....com>
Cc:	devicetree@...r.kernel.org, linux-kernel@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, kernel@...inux.com,
	linux-pci@...r.kernel.org, Lee Jones <lee.jones@...aro.org>,
	Gabriel Fernandez <gabriel.fernandez@...aro.org>
Subject: [PATCH v2 4/5] PCI: designware: Add disable IO support

ST sti SoCs PCIe IPs are built around DesignWare IP Core.
But in these SoCs PCIe IP doesn't support IO.

This patch adds the possibility to disable it through
a DT property, by creating an empty IO window and by
removing PCI_COMMAND_IO from the setup register.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@...com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@...aro.org>
---
 .../devicetree/bindings/pci/designware-pcie.txt    |  2 ++
 drivers/pci/host/pcie-designware.c                 | 24 ++++++++++++++++++++--
 drivers/pci/host/pcie-designware.h                 |  1 +
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/pci/designware-pcie.txt b/Documentation/devicetree/bindings/pci/designware-pcie.txt
index 9f4faa8..40544d4 100644
--- a/Documentation/devicetree/bindings/pci/designware-pcie.txt
+++ b/Documentation/devicetree/bindings/pci/designware-pcie.txt
@@ -26,3 +26,5 @@ Optional properties:
 - bus-range: PCI bus numbers covered (it is recommended for new devicetrees to
   specify this property, to keep backwards compatibility a range of 0x00-0xff
   is assumed if not present)
+- disable_io_support: set this property for PCIe host controller without IO
+  port access
diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
index 1f4ea6f..f9d70f5 100644
--- a/drivers/pci/host/pcie-designware.c
+++ b/drivers/pci/host/pcie-designware.c
@@ -471,6 +471,9 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
 		return -EINVAL;
 	}
 
+	pp->disable_io_support = of_property_read_bool(np,
+			"disable_io_support");
+
 	if (IS_ENABLED(CONFIG_PCI_MSI)) {
 		if (!pp->ops->msi_host_init) {
 			pp->irq_domain = irq_domain_add_linear(pp->dev->of_node,
@@ -704,6 +707,7 @@ static struct pci_ops dw_pcie_ops = {
 static int dw_pcie_setup(int nr, struct pci_sys_data *sys)
 {
 	struct pcie_port *pp;
+	struct resource *res;
 
 	pp = sys_to_pcie(sys);
 
@@ -719,6 +723,18 @@ static int dw_pcie_setup(int nr, struct pci_sys_data *sys)
 	pci_add_resource_offset(&sys->resources, &pp->mem, sys->mem_offset);
 	pci_add_resource(&sys->resources, &pp->busn);
 
+	if (pp->disable_io_support) {
+		/* This PCIe controller does not support IO, set an empty one */
+		res = devm_kzalloc(pp->dev, sizeof(*res), GFP_KERNEL);
+		if (res) {
+			res->start = 0;
+			res->end = 0;
+			res->name = "PCIe empty IO space";
+			res->flags = IORESOURCE_IO;
+			pci_add_resource(&sys->resources, res);
+		}
+	}
+
 	return 1;
 }
 
@@ -822,8 +838,12 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
 	/* setup command register */
 	dw_pcie_readl_rc(pp, PCI_COMMAND, &val);
 	val &= 0xffff0000;
-	val |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY |
-		PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
+
+	if (!pp->disable_io_support)
+		val |= PCI_COMMAND_IO;
+
+	val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_SERR;
+
 	dw_pcie_writel_rc(pp, val, PCI_COMMAND);
 }
 
diff --git a/drivers/pci/host/pcie-designware.h b/drivers/pci/host/pcie-designware.h
index d0bbd27..027045d 100644
--- a/drivers/pci/host/pcie-designware.h
+++ b/drivers/pci/host/pcie-designware.h
@@ -52,6 +52,7 @@ struct pcie_port {
 	int			msi_irq;
 	struct irq_domain	*irq_domain;
 	unsigned long		msi_data;
+	bool			disable_io_support;
 	DECLARE_BITMAP(msi_irq_in_use, MAX_MSI_IRQS);
 };
 
-- 
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/