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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platform.c (5287B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Platform driver for the Synopsys DesignWare DMA Controller
      4 *
      5 * Copyright (C) 2007-2008 Atmel Corporation
      6 * Copyright (C) 2010-2011 ST Microelectronics
      7 * Copyright (C) 2013 Intel Corporation
      8 *
      9 * Some parts of this driver are derived from the original dw_dmac.
     10 */
     11
     12#include <linux/module.h>
     13#include <linux/device.h>
     14#include <linux/clk.h>
     15#include <linux/pm_runtime.h>
     16#include <linux/platform_device.h>
     17#include <linux/dmaengine.h>
     18#include <linux/dma-mapping.h>
     19#include <linux/of.h>
     20#include <linux/acpi.h>
     21
     22#include "internal.h"
     23
     24#define DRV_NAME	"dw_dmac"
     25
     26static int dw_probe(struct platform_device *pdev)
     27{
     28	const struct dw_dma_chip_pdata *match;
     29	struct dw_dma_chip_pdata *data;
     30	struct dw_dma_chip *chip;
     31	struct device *dev = &pdev->dev;
     32	int err;
     33
     34	match = device_get_match_data(dev);
     35	if (!match)
     36		return -ENODEV;
     37
     38	data = devm_kmemdup(&pdev->dev, match, sizeof(*match), GFP_KERNEL);
     39	if (!data)
     40		return -ENOMEM;
     41
     42	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
     43	if (!chip)
     44		return -ENOMEM;
     45
     46	chip->irq = platform_get_irq(pdev, 0);
     47	if (chip->irq < 0)
     48		return chip->irq;
     49
     50	chip->regs = devm_platform_ioremap_resource(pdev, 0);
     51	if (IS_ERR(chip->regs))
     52		return PTR_ERR(chip->regs);
     53
     54	err = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
     55	if (err)
     56		return err;
     57
     58	if (!data->pdata)
     59		data->pdata = dev_get_platdata(dev);
     60	if (!data->pdata)
     61		data->pdata = dw_dma_parse_dt(pdev);
     62
     63	chip->dev = dev;
     64	chip->id = pdev->id;
     65	chip->pdata = data->pdata;
     66
     67	data->chip = chip;
     68
     69	chip->clk = devm_clk_get_optional(chip->dev, "hclk");
     70	if (IS_ERR(chip->clk))
     71		return PTR_ERR(chip->clk);
     72	err = clk_prepare_enable(chip->clk);
     73	if (err)
     74		return err;
     75
     76	pm_runtime_enable(&pdev->dev);
     77
     78	err = data->probe(chip);
     79	if (err)
     80		goto err_dw_dma_probe;
     81
     82	platform_set_drvdata(pdev, data);
     83
     84	dw_dma_of_controller_register(chip->dw);
     85
     86	dw_dma_acpi_controller_register(chip->dw);
     87
     88	return 0;
     89
     90err_dw_dma_probe:
     91	pm_runtime_disable(&pdev->dev);
     92	clk_disable_unprepare(chip->clk);
     93	return err;
     94}
     95
     96static int dw_remove(struct platform_device *pdev)
     97{
     98	struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
     99	struct dw_dma_chip *chip = data->chip;
    100	int ret;
    101
    102	dw_dma_acpi_controller_free(chip->dw);
    103
    104	dw_dma_of_controller_free(chip->dw);
    105
    106	ret = data->remove(chip);
    107	if (ret)
    108		dev_warn(chip->dev, "can't remove device properly: %d\n", ret);
    109
    110	pm_runtime_disable(&pdev->dev);
    111	clk_disable_unprepare(chip->clk);
    112
    113	return 0;
    114}
    115
    116static void dw_shutdown(struct platform_device *pdev)
    117{
    118	struct dw_dma_chip_pdata *data = platform_get_drvdata(pdev);
    119	struct dw_dma_chip *chip = data->chip;
    120
    121	/*
    122	 * We have to call do_dw_dma_disable() to stop any ongoing transfer. On
    123	 * some platforms we can't do that since DMA device is powered off.
    124	 * Moreover we have no possibility to check if the platform is affected
    125	 * or not. That's why we call pm_runtime_get_sync() / pm_runtime_put()
    126	 * unconditionally. On the other hand we can't use
    127	 * pm_runtime_suspended() because runtime PM framework is not fully
    128	 * used by the driver.
    129	 */
    130	pm_runtime_get_sync(chip->dev);
    131	do_dw_dma_disable(chip);
    132	pm_runtime_put_sync_suspend(chip->dev);
    133
    134	clk_disable_unprepare(chip->clk);
    135}
    136
    137#ifdef CONFIG_OF
    138static const struct of_device_id dw_dma_of_id_table[] = {
    139	{ .compatible = "snps,dma-spear1340", .data = &dw_dma_chip_pdata },
    140	{ .compatible = "renesas,rzn1-dma", .data = &dw_dma_chip_pdata },
    141	{}
    142};
    143MODULE_DEVICE_TABLE(of, dw_dma_of_id_table);
    144#endif
    145
    146#ifdef CONFIG_ACPI
    147static const struct acpi_device_id dw_dma_acpi_id_table[] = {
    148	{ "INTL9C60", (kernel_ulong_t)&dw_dma_chip_pdata },
    149	{ "80862286", (kernel_ulong_t)&dw_dma_chip_pdata },
    150	{ "808622C0", (kernel_ulong_t)&dw_dma_chip_pdata },
    151
    152	/* Elkhart Lake iDMA 32-bit (PSE DMA) */
    153	{ "80864BB4", (kernel_ulong_t)&xbar_chip_pdata },
    154	{ "80864BB5", (kernel_ulong_t)&xbar_chip_pdata },
    155	{ "80864BB6", (kernel_ulong_t)&xbar_chip_pdata },
    156
    157	{ }
    158};
    159MODULE_DEVICE_TABLE(acpi, dw_dma_acpi_id_table);
    160#endif
    161
    162#ifdef CONFIG_PM_SLEEP
    163
    164static int dw_suspend_late(struct device *dev)
    165{
    166	struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
    167	struct dw_dma_chip *chip = data->chip;
    168
    169	do_dw_dma_disable(chip);
    170	clk_disable_unprepare(chip->clk);
    171
    172	return 0;
    173}
    174
    175static int dw_resume_early(struct device *dev)
    176{
    177	struct dw_dma_chip_pdata *data = dev_get_drvdata(dev);
    178	struct dw_dma_chip *chip = data->chip;
    179	int ret;
    180
    181	ret = clk_prepare_enable(chip->clk);
    182	if (ret)
    183		return ret;
    184
    185	return do_dw_dma_enable(chip);
    186}
    187
    188#endif /* CONFIG_PM_SLEEP */
    189
    190static const struct dev_pm_ops dw_dev_pm_ops = {
    191	SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_suspend_late, dw_resume_early)
    192};
    193
    194static struct platform_driver dw_driver = {
    195	.probe		= dw_probe,
    196	.remove		= dw_remove,
    197	.shutdown       = dw_shutdown,
    198	.driver = {
    199		.name	= DRV_NAME,
    200		.pm	= &dw_dev_pm_ops,
    201		.of_match_table = of_match_ptr(dw_dma_of_id_table),
    202		.acpi_match_table = ACPI_PTR(dw_dma_acpi_id_table),
    203	},
    204};
    205
    206static int __init dw_init(void)
    207{
    208	return platform_driver_register(&dw_driver);
    209}
    210subsys_initcall(dw_init);
    211
    212static void __exit dw_exit(void)
    213{
    214	platform_driver_unregister(&dw_driver);
    215}
    216module_exit(dw_exit);
    217
    218MODULE_LICENSE("GPL v2");
    219MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller platform driver");
    220MODULE_ALIAS("platform:" DRV_NAME);