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 {"ARMHC500", 0}, /* ARM CoreSight ETM4x */ 26 {"ARMHC501", 0}, /* ARM CoreSight ETR */ 27 {"ARMHC502", 0}, /* ARM CoreSight STM */ 28 {"ARMHC503", 0}, /* ARM CoreSight Debug */ 29 {"ARMHC979", 0}, /* ARM CoreSight TPIU */ 30 {"ARMHC97C", 0}, /* ARM CoreSight SoC-400 TMC, SoC-600 ETF/ETB */ 31 {"ARMHC98D", 0}, /* ARM CoreSight Dynamic Replicator */ 32 {"ARMHC9CA", 0}, /* ARM CoreSight CATU */ 33 {"ARMHC9FF", 0}, /* ARM CoreSight Dynamic Funnel */ 34 {"", 0}, 35 }; 36 37 static void amba_register_dummy_clk(void) 38 { 39 static struct clk *amba_dummy_clk; 40 41 /* If clock already registered */ 42 if (amba_dummy_clk) 43 return; 44 45 amba_dummy_clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, 0, 0); 46 clk_register_clkdev(amba_dummy_clk, "apb_pclk", NULL); 47 } 48 49 static int amba_handler_attach(struct acpi_device *adev, 50 const struct acpi_device_id *id) 51 { 52 struct acpi_device *parent = acpi_dev_parent(adev); 53 struct amba_device *dev; 54 struct resource_entry *rentry; 55 struct list_head resource_list; 56 bool address_found = false; 57 int irq_no = 0; 58 int ret; 59 60 /* If the ACPI node already has a physical device attached, skip it. */ 61 if (adev->physical_node_count) 62 return 0; 63 64 dev = amba_device_alloc(dev_name(&adev->dev), 0, 0); 65 if (!dev) { 66 dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n", 67 __func__); 68 return -ENOMEM; 69 } 70 71 INIT_LIST_HEAD(&resource_list); 72 ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); 73 if (ret < 0) 74 goto err_free; 75 76 list_for_each_entry(rentry, &resource_list, node) { 77 switch (resource_type(rentry->res)) { 78 case IORESOURCE_MEM: 79 if (!address_found) { 80 dev->res = *rentry->res; 81 dev->res.name = dev_name(&dev->dev); 82 address_found = true; 83 } 84 break; 85 case IORESOURCE_IRQ: 86 if (irq_no < AMBA_NR_IRQS) 87 dev->irq[irq_no++] = rentry->res->start; 88 break; 89 default: 90 dev_warn(&adev->dev, "Invalid resource\n"); 91 break; 92 } 93 } 94 95 acpi_dev_free_resource_list(&resource_list); 96 97 /* 98 * If the ACPI node has a parent and that parent has a physical device 99 * attached to it, that physical device should be the parent of 100 * the amba device we are about to create. 101 */ 102 if (parent) 103 dev->dev.parent = acpi_get_first_physical_node(parent); 104 105 ACPI_COMPANION_SET(&dev->dev, adev); 106 107 ret = amba_device_add(dev, &iomem_resource); 108 if (ret) { 109 dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n", 110 __func__, ret); 111 goto err_free; 112 } 113 114 return 1; 115 116 err_free: 117 amba_device_put(dev); 118 return ret; 119 } 120 121 static struct acpi_scan_handler amba_handler = { 122 .ids = amba_id_list, 123 .attach = amba_handler_attach, 124 }; 125 126 void __init acpi_amba_init(void) 127 { 128 amba_register_dummy_clk(); 129 acpi_scan_add_handler(&amba_handler); 130 } 131