1 // SPDX-License-Identifier: GPL-2.0-only 2 3 /* 4 * ACPI support for platform bus type. 5 * 6 * Copyright (C) 2015, Linaro Ltd 7 * Author: Graeme Gregory <graeme.gregory@linaro.org> 8 */ 9 10 #include <linux/acpi.h> 11 #include <linux/amba/bus.h> 12 #include <linux/clkdev.h> 13 #include <linux/clk-provider.h> 14 #include <linux/device.h> 15 #include <linux/err.h> 16 #include <linux/ioport.h> 17 #include <linux/kernel.h> 18 #include <linux/module.h> 19 20 #include "init.h" 21 22 static const struct acpi_device_id amba_id_list[] = { 23 {"ARMH0061", 0}, /* PL061 GPIO Device */ 24 {"ARMH0330", 0}, /* ARM DMA Controller DMA-330 */ 25 {"ARMHC501", 0}, /* ARM CoreSight ETR */ 26 {"ARMHC502", 0}, /* ARM CoreSight STM */ 27 {"ARMHC503", 0}, /* ARM CoreSight Debug */ 28 {"ARMHC979", 0}, /* ARM CoreSight TPIU */ 29 {"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */ 30 {"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */ 31 {"ARMHC9CA", 0}, /* ARM CoreSight CATU */ 32 {"ARMHC9FF", 0}, /* ARM CoreSight Dynamic Funnel */ 33 {"", 0}, 34 }; 35 36 static void amba_register_dummy_clk(void) 37 { 38 static struct clk *amba_dummy_clk; 39 40 /* If clock already registered */ 41 if (amba_dummy_clk) 42 return; 43 44 amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0); 45 clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL); 46 } 47 48 static int amba_handler_attach(struct acpi_device *adev, 49 const struct acpi_device_id *id) 50 { 51 struct acpi_device *parent = acpi_dev_parent(adev); 52 struct amba_device *dev; 53 struct resource_entry *rentry; 54 struct list_head resource_list; 55 bool address_found = false; 56 int irq_no = 0; 57 int ret; 58 59 /* If the ACPI node already has a physical device attached, skip it. */ 60 if (adev->physical_node_count) 61 return 0; 62 63 dev = amba_device_alloc(dev_name(&adev->dev), 0, 0); 64 if (!dev) { 65 dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n", 66 __func__); 67 return -ENOMEM; 68 } 69 70 INIT_LIST_HEAD(&resource_list); 71 ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 72 if (ret < 0) 73 goto err_free; 74 75 list_for_each_entry(rentry, &resource_list, node) { 76 switch (resource_type(rentry->res)) { 77 case IORESOURCE_MEM: 78 if (!address_found) { 79 dev->res = *rentry->res; 80 dev->res.name = dev_name(&dev->dev); 81 address_found = true; 82 } 83 break; 84 case IORESOURCE_IRQ: 85 if (irq_no < AMBA_NR_IRQS) 86 dev->irq[irq_no++] = rentry->res->start; 87 break; 88 default: 89 dev_warn(&adev->dev, "Invalid resource\n"); 90 break; 91 } 92 } 93 94 acpi_dev_free_resource_list(&resource_list); 95 96 /* 97 * If the ACPI node has a parent and that parent has a physical device 98 * attached to it, that physical device should be the parent of 99 * the amba device we are about to create. 100 */ 101 if (parent) 102 dev->dev.parent = acpi_get_first_physical_node(parent); 103 104 device_set_node(&dev->dev, acpi_fwnode_handle(adev)); 105 106 ret = amba_device_add(dev, &iomem_resource); 107 if (ret) { 108 dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n", 109 __func__, ret); 110 goto err_free; 111 } 112 113 return 1; 114 115 err_free: 116 amba_device_put(dev); 117 return ret; 118 } 119 120 static struct acpi_scan_handler amba_handler = { 121 .ids = amba_id_list, 122 .attach = amba_handler_attach, 123 }; 124 125 void __init acpi_amba_init(void) 126 { 127 amba_register_dummy_clk(); 128 acpi_scan_add_handler(&amba_handler); 129 } 130