cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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acpi_amba.c (3156B)

      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 "internal.h"
     21
     22static const struct acpi_device_id amba_id_list[] = {
     23	{"ARMH0061", 0}, /* PL061 GPIO Device */
     24	{"ARMHC500", 0}, /* ARM CoreSight ETM4x */
     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
     36static 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
     48static int amba_handler_attach(struct acpi_device *adev,
     49				const struct acpi_device_id *id)
     50{
     51	struct amba_device *dev;
     52	struct resource_entry *rentry;
     53	struct list_head resource_list;
     54	bool address_found = false;
     55	int irq_no = 0;
     56	int ret;
     57
     58	/* If the ACPI node already has a physical device attached, skip it. */
     59	if (adev->physical_node_count)
     60		return 0;
     61
     62	dev = amba_device_alloc(dev_name(&adev->dev), 0, 0);
     63	if (!dev) {
     64		dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n",
     65			__func__);
     66		return -ENOMEM;
     67	}
     68
     69	INIT_LIST_HEAD(&resource_list);
     70	ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
     71	if (ret < 0)
     72		goto err_free;
     73
     74	list_for_each_entry(rentry, &resource_list, node) {
     75		switch (resource_type(rentry->res)) {
     76		case IORESOURCE_MEM:
     77			if (!address_found) {
     78				dev->res = *rentry->res;
     79				dev->res.name = dev_name(&dev->dev);
     80				address_found = true;
     81			}
     82			break;
     83		case IORESOURCE_IRQ:
     84			if (irq_no < AMBA_NR_IRQS)
     85				dev->irq[irq_no++] = rentry->res->start;
     86			break;
     87		default:
     88			dev_warn(&adev->dev, "Invalid resource\n");
     89			break;
     90		}
     91	}
     92
     93	acpi_dev_free_resource_list(&resource_list);
     94
     95	/*
     96	 * If the ACPI node has a parent and that parent has a physical device
     97	 * attached to it, that physical device should be the parent of
     98	 * the amba device we are about to create.
     99	 */
    100	if (adev->parent)
    101		dev->dev.parent = acpi_get_first_physical_node(adev->parent);
    102
    103	ACPI_COMPANION_SET(&dev->dev, adev);
    104
    105	ret = amba_device_add(dev, &iomem_resource);
    106	if (ret) {
    107		dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n",
    108		       __func__, ret);
    109		goto err_free;
    110	}
    111
    112	return 1;
    113
    114err_free:
    115	amba_device_put(dev);
    116	return ret;
    117}
    118
    119static struct acpi_scan_handler amba_handler = {
    120	.ids = amba_id_list,
    121	.attach = amba_handler_attach,
    122};
    123
    124void __init acpi_amba_init(void)
    125{
    126	amba_register_dummy_clk();
    127	acpi_scan_add_handler(&amba_handler);
    128}