PCI: tegra: Move PCIe driver to drivers/pci/host

Move the PCIe driver from arch/arm/mach-tegra into the drivers/pci/host
directory. The motivation is to collect various host controller drivers
in the same location in order to facilitate refactoring.

The Tegra PCIe driver has been largely rewritten, both in order to turn
it into a proper platform driver and to add MSI (based on code by
Krishna Kishore <kthota@nvidia.com>) as well as device tree support.
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
[swarren, split DT changes into a separate patch in another branch]
Signed-off-by: Stephen Warren <swarren@nvidia.com>

Documentation/devicetree/bindings/pci/nvidia,tegra20-pcie.txt

+NVIDIA Tegra PCIe controller
+
+Required properties:
+- compatible: "nvidia,tegra20-pcie"
+- device_type: Must be "pci"
+- reg: A list of physical base address and length for each set of controller
+  registers. Must contain an entry for each entry in the reg-names property.
+- reg-names: Must include the following entries:
+  "pads": PADS registers
+  "afi": AFI registers
+  "cs": configuration space region
+- interrupts: A list of interrupt outputs of the controller. Must contain an
+  entry for each entry in the interrupt-names property.
+- interrupt-names: Must include the following entries:
+  "intr": The Tegra interrupt that is asserted for controller interrupts
+  "msi": The Tegra interrupt that is asserted when an MSI is received
+- pex-clk-supply: Supply voltage for internal reference clock
+- vdd-supply: Power supply for controller (1.05V)
+- bus-range: Range of bus numbers associated with this controller
+- #address-cells: Address representation for root ports (must be 3)
+  - cell 0 specifies the bus and device numbers of the root port:
+    [23:16]: bus number
+    [15:11]: device number
+  - cell 1 denotes the upper 32 address bits and should be 0
+  - cell 2 contains the lower 32 address bits and is used to translate to the
+    CPU address space
+- #size-cells: Size representation for root ports (must be 2)
+- ranges: Describes the translation of addresses for root ports and standard
+  PCI regions. The entries must be 6 cells each, where the first three cells
+  correspond to the address as described for the #address-cells property
+  above, the fourth cell is the physical CPU address to translate to and the
+  fifth and six cells are as described for the #size-cells property above.
+  - The first two entries are expected to translate the addresses for the root
+    port registers, which are referenced by the assigned-addresses property of
+    the root port nodes (see below).
+  - The remaining entries setup the mapping for the standard I/O, memory and
+    prefetchable PCI regions. The first cell determines the type of region
+    that is setup:
+    - 0x81000000: I/O memory region
+    - 0x82000000: non-prefetchable memory region
+    - 0xc2000000: prefetchable memory region
+  Please refer to the standard PCI bus binding document for a more detailed
+  explanation.
+- clocks: List of clock inputs of the controller. Must contain an entry for
+  each entry in the clock-names property.
+- clock-names: Must include the following entries:
+  "pex": The Tegra clock of that name
+  "afi": The Tegra clock of that name
+  "pcie_xclk": The Tegra clock of that name
+  "pll_e": The Tegra clock of that name
+
+Root ports are defined as subnodes of the PCIe controller node.
+
+Required properties:
+- device_type: Must be "pci"
+- assigned-addresses: Address and size of the port configuration registers
+- reg: PCI bus address of the root port
+- #address-cells: Must be 3
+- #size-cells: Must be 2
+- ranges: Sub-ranges distributed from the PCIe controller node. An empty
+  property is sufficient.
+- nvidia,num-lanes: Number of lanes to use for this port. Valid combinations
+  are:
+  - Root port 0 uses 4 lanes, root port 1 is unused.
+  - Both root ports use 2 lanes.
+
+Example:
+
+SoC DTSI:
+
+	pcie-controller {
+		compatible = "nvidia,tegra20-pcie";
+		device_type = "pci";
+		reg = <0x80003000 0x00000800   /* PADS registers */
+		       0x80003800 0x00000200   /* AFI registers */
+		       0x90000000 0x10000000>; /* configuration space */
+		reg-names = "pads", "afi", "cs";
+		interrupts = <0 98 0x04   /* controller interrupt */
+		              0 99 0x04>; /* MSI interrupt */
+		interrupt-names = "intr", "msi";
+
+		bus-range = <0x00 0xff>;
+		#address-cells = <3>;
+		#size-cells = <2>;
+
+		ranges = <0x82000000 0 0x80000000 0x80000000 0 0x00001000   /* port 0 registers */
+			  0x82000000 0 0x80001000 0x80001000 0 0x00001000   /* port 1 registers */
+			  0x81000000 0 0          0x82000000 0 0x00010000   /* downstream I/O */
+			  0x82000000 0 0xa0000000 0xa0000000 0 0x10000000   /* non-prefetchable memory */
+			  0xc2000000 0 0xb0000000 0xb0000000 0 0x10000000>; /* prefetchable memory */
+
+		clocks = <&tegra_car 70>, <&tegra_car 72>, <&tegra_car 74>,
+			 <&tegra_car 118>;
+		clock-names = "pex", "afi", "pcie_xclk", "pll_e";
+		status = "disabled";
+
+		pci@1,0 {
+			device_type = "pci";
+			assigned-addresses = <0x82000800 0 0x80000000 0 0x1000>;
+			reg = <0x000800 0 0 0 0>;
+			status = "disabled";
+
+			#address-cells = <3>;
+			#size-cells = <2>;
+
+			ranges;
+
+			nvidia,num-lanes = <2>;
+		};
+
+		pci@2,0 {
+			device_type = "pci";
+			assigned-addresses = <0x82001000 0 0x80001000 0 0x1000>;
+			reg = <0x001000 0 0 0 0>;
+			status = "disabled";
+
+			#address-cells = <3>;
+			#size-cells = <2>;
+
+			ranges;
+
+			nvidia,num-lanes = <2>;
+		};
+	};
+
+
+Board DTS:
+
+	pcie-controller {
+		status = "okay";
+
+		vdd-supply = <&pci_vdd_reg>;
+		pex-clk-supply = <&pci_clk_reg>;
+
+		/* root port 00:01.0 */
+		pci@1,0 {
+			status = "okay";
+
+			/* bridge 01:00.0 (optional) */
+			pci@0,0 {
+				reg = <0x010000 0 0 0 0>;
+
+				#address-cells = <3>;
+				#size-cells = <2>;
+
+				device_type = "pci";
+
+				/* endpoint 02:00.0 */
+				pci@0,0 {
+					reg = <0x020000 0 0 0 0>;
+				};
+			};
+		};
+	};
+
+Note that devices on the PCI bus are dynamically discovered using PCI's bus
+enumeration and therefore don't need corresponding device nodes in DT. However
+if a device on the PCI bus provides a non-probeable bus such as I2C or SPI,
+device nodes need to be added in order to allow the bus' children to be
+instantiated at the proper location in the operating system's device tree (as
+illustrated by the optional nodes in the example above).

arch/arm/mach-tegra/Kconfig

@@ -21,6 +21,8 @@ config ARCH_TEGRA
 	select USB_ULPI if USB_PHY
 	select USB_ULPI_VIEWPORT if USB_PHY
 	select USE_OF
+	select MIGHT_HAVE_PCI
+	select ARCH_SUPPORTS_MSI
 	help
 	  This enables support for NVIDIA Tegra based systems.
 
@@ -60,11 +62,6 @@ config ARCH_TEGRA_114_SOC
 	  Support for NVIDIA Tegra T114 processor family, based on the
 	  ARM CortexA15MP CPU
 
-config TEGRA_PCI
-	bool "PCI Express support"
-	depends on ARCH_TEGRA_2x_SOC
-	select PCI
-
 config TEGRA_AHB
 	bool "Enable AHB driver for NVIDIA Tegra SoCs"
 	default y

arch/arm/mach-tegra/Makefile

@@ -29,7 +29,6 @@ obj-$(CONFIG_ARCH_TEGRA_3x_SOC)		+= cpuidle-tegra30.o
 endif
 obj-$(CONFIG_SMP)			+= platsmp.o headsmp.o
 obj-$(CONFIG_HOTPLUG_CPU)               += hotplug.o
-obj-$(CONFIG_TEGRA_PCI)			+= pcie.o
 
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)	+= tegra114_speedo.o
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)	+= sleep-tegra30.o
@@ -38,6 +37,4 @@ ifeq ($(CONFIG_CPU_IDLE),y)
 obj-$(CONFIG_ARCH_TEGRA_114_SOC)	+= cpuidle-tegra114.o
 endif
 
-obj-$(CONFIG_ARCH_TEGRA_2x_SOC)		+= board-harmony-pcie.o
-
 obj-$(CONFIG_ARCH_TEGRA_2x_SOC)		+= board-paz00.o

arch/arm/mach-tegra/board-harmony-pcie.c

-/*
- * arch/arm/mach-tegra/board-harmony-pcie.c
- *
- * Copyright (C) 2010 CompuLab, Ltd.
- * Mike Rapoport <mike@compulab.co.il>
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- */
-
-#include <linux/kernel.h>
-#include <linux/gpio.h>
-#include <linux/err.h>
-#include <linux/of_gpio.h>
-#include <linux/regulator/consumer.h>
-
-#include <asm/mach-types.h>
-
-#include "board.h"
-
-#ifdef CONFIG_TEGRA_PCI
-
-int __init harmony_pcie_init(void)
-{
-	struct device_node *np;
-	int en_vdd_1v05;
-	struct regulator *regulator = NULL;
-	int err;
-
-	np = of_find_node_by_path("/regulators/regulator@3");
-	if (!np) {
-		pr_err("%s: of_find_node_by_path failed\n", __func__);
-		return -ENODEV;
-	}
-
-	en_vdd_1v05 = of_get_named_gpio(np, "gpio", 0);
-	if (en_vdd_1v05 < 0) {
-		pr_err("%s: of_get_named_gpio failed: %d\n", __func__,
-		       en_vdd_1v05);
-		return en_vdd_1v05;
-	}
-
-	err = gpio_request(en_vdd_1v05, "EN_VDD_1V05");
-	if (err) {
-		pr_err("%s: gpio_request failed: %d\n", __func__, err);
-		return err;
-	}
-
-	gpio_direction_output(en_vdd_1v05, 1);
-
-	regulator = regulator_get(NULL, "vdd_ldo0,vddio_pex_clk");
-	if (IS_ERR(regulator)) {
-		err = PTR_ERR(regulator);
-		pr_err("%s: regulator_get failed: %d\n", __func__, err);
-		goto err_reg;
-	}
-
-	err = regulator_enable(regulator);
-	if (err) {
-		pr_err("%s: regulator_enable failed: %d\n", __func__, err);
-		goto err_en;
-	}
-
-	err = tegra_pcie_init(true, true);
-	if (err) {
-		pr_err("%s: tegra_pcie_init failed: %d\n", __func__, err);
-		goto err_pcie;
-	}
-
-	return 0;
-
-err_pcie:
-	regulator_disable(regulator);
-err_en:
-	regulator_put(regulator);
-err_reg:
-	gpio_free(en_vdd_1v05);
-
-	return err;
-}
-
-#endif

arch/arm/mach-tegra/board.h

@@ -31,7 +31,6 @@ void __init tegra_init_early(void);
 void __init tegra_map_common_io(void);
 void __init tegra_init_irq(void);
 void __init tegra_dt_init_irq(void);
-int __init tegra_pcie_init(bool init_port0, bool init_port1);
 
 void tegra_init_late(void);
 
@@ -48,13 +47,6 @@ int __init tegra_powergate_debugfs_init(void);
 static inline int tegra_powergate_debugfs_init(void) { return 0; }
 #endif
 
-int __init harmony_regulator_init(void);
-#ifdef CONFIG_TEGRA_PCI
-int __init harmony_pcie_init(void);
-#else
-static inline int harmony_pcie_init(void) { return 0; }
-#endif
-
 void __init tegra_paz00_wifikill_init(void);
 
 #endif

arch/arm/mach-tegra/iomap.h

@@ -286,9 +286,6 @@
 #define IO_APB_VIRT	IOMEM(0xFE300000)
 #define IO_APB_SIZE	SZ_1M
 
-#define TEGRA_PCIE_BASE		0x80000000
-#define TEGRA_PCIE_IO_BASE	(TEGRA_PCIE_BASE + SZ_4M)
-
 #define IO_TO_VIRT_BETWEEN(p, st, sz)	((p) >= (st) && (p) < ((st) + (sz)))
 #define IO_TO_VIRT_XLATE(p, pst, vst)	(((p) - (pst) + (vst)))
 

arch/arm/mach-tegra/tegra.c

@@ -116,28 +116,6 @@ static void __init tegra_dt_init(void)
 				tegra20_auxdata_lookup, parent);
 }
 
-static void __init trimslice_init(void)
-{
-#ifdef CONFIG_TEGRA_PCI
-	int ret;
-
-	ret = tegra_pcie_init(true, true);
-	if (ret)
-		pr_err("tegra_pci_init() failed: %d\n", ret);
-#endif
-}
-
-static void __init harmony_init(void)
-{
-#ifdef CONFIG_TEGRA_PCI
-	int ret;
-
-	ret = harmony_pcie_init();
-	if (ret)
-		pr_err("harmony_pcie_init() failed: %d\n", ret);
-#endif
-}
-
 static void __init paz00_init(void)
 {
 	if (IS_ENABLED(CONFIG_ARCH_TEGRA_2x_SOC))
@@ -148,8 +126,6 @@ static struct {
 	char *machine;
 	void (*init)(void);
 } board_init_funcs[] = {
-	{ "compulab,trimslice", trimslice_init },
-	{ "nvidia,harmony", harmony_init },
 	{ "compal,paz00", paz00_init },
 };
 

drivers/pci/host/Kconfig

@@ -14,4 +14,8 @@ config PCI_EXYNOS
 	select PCIEPORTBUS
 	select PCIE_DW
 
+config PCI_TEGRA
+	bool "NVIDIA Tegra PCIe controller"
+	depends on ARCH_TEGRA
+
 endmenu

drivers/pci/host/Makefile

 obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
 obj-$(CONFIG_PCIE_DW) += pcie-designware.o
+obj-$(CONFIG_PCI_TEGRA) += pci-tegra.o