PCI: Move DesignWare IP support to new drivers/pci/dwc/ directory

Group all the PCI drivers that use DesignWare core in dwc directory.
dwc IP is capable of operating in both host mode and device mode and
keeping it inside the *host* directory is misleading.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
Acked-By: Joao Pinto <jpinto@synopsys.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Minghuan Lian <minghuan.Lian@freescale.com>
Cc: Mingkai Hu <mingkai.hu@freescale.com>
Cc: Roy Zang <tie-fei.zang@freescale.com>
Cc: Richard Zhu <hongxing.zhu@nxp.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Murali Karicheri <m-karicheri2@ti.com>
Cc: Pratyush Anand <pratyush.anand@gmail.com>
Cc: Niklas Cassel <niklas.cassel@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Zhou Wang <wangzhou1@hisilicon.com>
Cc: Gabriele Paoloni <gabriele.paoloni@huawei.com>
Cc: Stanimir Varbanov <svarbanov@mm-sol.com>

1 files changed, 254 insertions, 0 deletions

diff --git a/drivers/pci/dwc/pcie-armada8k.c b/drivers/pci/dwc/pcie-armada8k.c
new file mode 100644
index 000000000000..0ac0f18690f2
--- /dev/null
+++ b/drivers/pci/dwc/pcie-armada8k.c
@@ -0,0 +1,254 @@
+/*
+ * PCIe host controller driver for Marvell Armada-8K SoCs
+ *
+ * Armada-8K PCIe Glue Layer Source Code
+ *
+ * Copyright (C) 2016 Marvell Technology Group Ltd.
+ *
+ * Author: Yehuda Yitshak <yehuday@marvell.com>
+ * Author: Shadi Ammouri <shadi@marvell.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/resource.h>
+#include <linux/of_pci.h>
+#include <linux/of_irq.h>
+
+#include "pcie-designware.h"
+
+struct armada8k_pcie {
+	struct pcie_port pp;		/* pp.dbi_base is DT ctrl */
+	struct clk *clk;
+};
+
+#define PCIE_VENDOR_REGS_OFFSET		0x8000
+
+#define PCIE_GLOBAL_CONTROL_REG		(PCIE_VENDOR_REGS_OFFSET + 0x0)
+#define PCIE_APP_LTSSM_EN		BIT(2)
+#define PCIE_DEVICE_TYPE_SHIFT		4
+#define PCIE_DEVICE_TYPE_MASK		0xF
+#define PCIE_DEVICE_TYPE_RC		0x4 /* Root complex */
+
+#define PCIE_GLOBAL_STATUS_REG		(PCIE_VENDOR_REGS_OFFSET + 0x8)
+#define PCIE_GLB_STS_RDLH_LINK_UP	BIT(1)
+#define PCIE_GLB_STS_PHY_LINK_UP	BIT(9)
+
+#define PCIE_GLOBAL_INT_CAUSE1_REG	(PCIE_VENDOR_REGS_OFFSET + 0x1C)
+#define PCIE_GLOBAL_INT_MASK1_REG	(PCIE_VENDOR_REGS_OFFSET + 0x20)
+#define PCIE_INT_A_ASSERT_MASK		BIT(9)
+#define PCIE_INT_B_ASSERT_MASK		BIT(10)
+#define PCIE_INT_C_ASSERT_MASK		BIT(11)
+#define PCIE_INT_D_ASSERT_MASK		BIT(12)
+
+#define PCIE_ARCACHE_TRC_REG		(PCIE_VENDOR_REGS_OFFSET + 0x50)
+#define PCIE_AWCACHE_TRC_REG		(PCIE_VENDOR_REGS_OFFSET + 0x54)
+#define PCIE_ARUSER_REG			(PCIE_VENDOR_REGS_OFFSET + 0x5C)
+#define PCIE_AWUSER_REG			(PCIE_VENDOR_REGS_OFFSET + 0x60)
+/*
+ * AR/AW Cache defauls: Normal memory, Write-Back, Read / Write
+ * allocate
+ */
+#define ARCACHE_DEFAULT_VALUE		0x3511
+#define AWCACHE_DEFAULT_VALUE		0x5311
+
+#define DOMAIN_OUTER_SHAREABLE		0x2
+#define AX_USER_DOMAIN_MASK		0x3
+#define AX_USER_DOMAIN_SHIFT		4
+
+#define to_armada8k_pcie(x)	container_of(x, struct armada8k_pcie, pp)
+
+static int armada8k_pcie_link_up(struct pcie_port *pp)
+{
+	u32 reg;
+	u32 mask = PCIE_GLB_STS_RDLH_LINK_UP | PCIE_GLB_STS_PHY_LINK_UP;
+
+	reg = dw_pcie_readl_rc(pp, PCIE_GLOBAL_STATUS_REG);
+
+	if ((reg & mask) == mask)
+		return 1;
+
+	dev_dbg(pp->dev, "No link detected (Global-Status: 0x%08x).\n", reg);
+	return 0;
+}
+
+static void armada8k_pcie_establish_link(struct armada8k_pcie *pcie)
+{
+	struct pcie_port *pp = &pcie->pp;
+	u32 reg;
+
+	if (!dw_pcie_link_up(pp)) {
+		/* Disable LTSSM state machine to enable configuration */
+		reg = dw_pcie_readl_rc(pp, PCIE_GLOBAL_CONTROL_REG);
+		reg &= ~(PCIE_APP_LTSSM_EN);
+		dw_pcie_writel_rc(pp, PCIE_GLOBAL_CONTROL_REG, reg);
+	}
+
+	/* Set the device to root complex mode */
+	reg = dw_pcie_readl_rc(pp, PCIE_GLOBAL_CONTROL_REG);
+	reg &= ~(PCIE_DEVICE_TYPE_MASK << PCIE_DEVICE_TYPE_SHIFT);
+	reg |= PCIE_DEVICE_TYPE_RC << PCIE_DEVICE_TYPE_SHIFT;
+	dw_pcie_writel_rc(pp, PCIE_GLOBAL_CONTROL_REG, reg);
+
+	/* Set the PCIe master AxCache attributes */
+	dw_pcie_writel_rc(pp, PCIE_ARCACHE_TRC_REG, ARCACHE_DEFAULT_VALUE);
+	dw_pcie_writel_rc(pp, PCIE_AWCACHE_TRC_REG, AWCACHE_DEFAULT_VALUE);
+
+	/* Set the PCIe master AxDomain attributes */
+	reg = dw_pcie_readl_rc(pp, PCIE_ARUSER_REG);
+	reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
+	reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
+	dw_pcie_writel_rc(pp, PCIE_ARUSER_REG, reg);
+
+	reg = dw_pcie_readl_rc(pp, PCIE_AWUSER_REG);
+	reg &= ~(AX_USER_DOMAIN_MASK << AX_USER_DOMAIN_SHIFT);
+	reg |= DOMAIN_OUTER_SHAREABLE << AX_USER_DOMAIN_SHIFT;
+	dw_pcie_writel_rc(pp, PCIE_AWUSER_REG, reg);
+
+	/* Enable INT A-D interrupts */
+	reg = dw_pcie_readl_rc(pp, PCIE_GLOBAL_INT_MASK1_REG);
+	reg |= PCIE_INT_A_ASSERT_MASK | PCIE_INT_B_ASSERT_MASK |
+	       PCIE_INT_C_ASSERT_MASK | PCIE_INT_D_ASSERT_MASK;
+	dw_pcie_writel_rc(pp, PCIE_GLOBAL_INT_MASK1_REG, reg);
+
+	if (!dw_pcie_link_up(pp)) {
+		/* Configuration done. Start LTSSM */
+		reg = dw_pcie_readl_rc(pp, PCIE_GLOBAL_CONTROL_REG);
+		reg |= PCIE_APP_LTSSM_EN;
+		dw_pcie_writel_rc(pp, PCIE_GLOBAL_CONTROL_REG, reg);
+	}
+
+	/* Wait until the link becomes active again */
+	if (dw_pcie_wait_for_link(pp))
+		dev_err(pp->dev, "Link not up after reconfiguration\n");
+}
+
+static void armada8k_pcie_host_init(struct pcie_port *pp)
+{
+	struct armada8k_pcie *pcie = to_armada8k_pcie(pp);
+
+	dw_pcie_setup_rc(pp);
+	armada8k_pcie_establish_link(pcie);
+}
+
+static irqreturn_t armada8k_pcie_irq_handler(int irq, void *arg)
+{
+	struct armada8k_pcie *pcie = arg;
+	struct pcie_port *pp = &pcie->pp;
+	u32 val;
+
+	/*
+	 * Interrupts are directly handled by the device driver of the
+	 * PCI device. However, they are also latched into the PCIe
+	 * controller, so we simply discard them.
+	 */
+	val = dw_pcie_readl_rc(pp, PCIE_GLOBAL_INT_CAUSE1_REG);
+	dw_pcie_writel_rc(pp, PCIE_GLOBAL_INT_CAUSE1_REG, val);
+
+	return IRQ_HANDLED;
+}
+
+static struct pcie_host_ops armada8k_pcie_host_ops = {
+	.link_up = armada8k_pcie_link_up,
+	.host_init = armada8k_pcie_host_init,
+};
+
+static int armada8k_add_pcie_port(struct armada8k_pcie *pcie,
+				  struct platform_device *pdev)
+{
+	struct pcie_port *pp = &pcie->pp;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	pp->root_bus_nr = -1;
+	pp->ops = &armada8k_pcie_host_ops;
+
+	pp->irq = platform_get_irq(pdev, 0);
+	if (!pp->irq) {
+		dev_err(dev, "failed to get irq for port\n");
+		return -ENODEV;
+	}
+
+	ret = devm_request_irq(dev, pp->irq, armada8k_pcie_irq_handler,
+			       IRQF_SHARED, "armada8k-pcie", pcie);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", pp->irq);
+		return ret;
+	}
+
+	ret = dw_pcie_host_init(pp);
+	if (ret) {
+		dev_err(dev, "failed to initialize host: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int armada8k_pcie_probe(struct platform_device *pdev)
+{
+	struct armada8k_pcie *pcie;
+	struct pcie_port *pp;
+	struct device *dev = &pdev->dev;
+	struct resource *base;
+	int ret;
+
+	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+	if (!pcie)
+		return -ENOMEM;
+
+	pcie->clk = devm_clk_get(dev, NULL);
+	if (IS_ERR(pcie->clk))
+		return PTR_ERR(pcie->clk);
+
+	clk_prepare_enable(pcie->clk);
+
+	pp = &pcie->pp;
+	pp->dev = dev;
+
+	/* Get the dw-pcie unit configuration/control registers base. */
+	base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl");
+	pp->dbi_base = devm_ioremap_resource(dev, base);
+	if (IS_ERR(pp->dbi_base)) {
+		dev_err(dev, "couldn't remap regs base %p\n", base);
+		ret = PTR_ERR(pp->dbi_base);
+		goto fail;
+	}
+
+	ret = armada8k_add_pcie_port(pcie, pdev);
+	if (ret)
+		goto fail;
+
+	return 0;
+
+fail:
+	if (!IS_ERR(pcie->clk))
+		clk_disable_unprepare(pcie->clk);
+
+	return ret;
+}
+
+static const struct of_device_id armada8k_pcie_of_match[] = {
+	{ .compatible = "marvell,armada8k-pcie", },
+	{},
+};
+
+static struct platform_driver armada8k_pcie_driver = {
+	.probe		= armada8k_pcie_probe,
+	.driver = {
+		.name	= "armada8k-pcie",
+		.of_match_table = of_match_ptr(armada8k_pcie_of_match),
+	},
+};
+builtin_platform_driver(armada8k_pcie_driver);