vfio_platform_calxedaxgmac.c

 1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * VFIO platform driver specialized for Calxeda xgmac reset
 4 * reset code is inherited from calxeda xgmac native driver
 5 *
 6 * Copyright 2010-2011 Calxeda, Inc.
 7 * Copyright (c) 2015 Linaro Ltd.
 8 *              www.linaro.org
 9 */
10
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/init.h>
14#include <linux/io.h>
15
16#include "../vfio_platform_private.h"
17
18#define DRIVER_VERSION  "0.1"
19#define DRIVER_AUTHOR   "Eric Auger <eric.auger@linaro.org>"
20#define DRIVER_DESC     "Reset support for Calxeda xgmac vfio platform device"
21
22/* XGMAC Register definitions */
23#define XGMAC_CONTROL           0x00000000      /* MAC Configuration */
24
25/* DMA Control and Status Registers */
26#define XGMAC_DMA_CONTROL       0x00000f18      /* Ctrl (Operational Mode) */
27#define XGMAC_DMA_INTR_ENA      0x00000f1c      /* Interrupt Enable */
28
29/* DMA Control register defines */
30#define DMA_CONTROL_ST          0x00002000      /* Start/Stop Transmission */
31#define DMA_CONTROL_SR          0x00000002      /* Start/Stop Receive */
32
33/* Common MAC defines */
34#define MAC_ENABLE_TX           0x00000008      /* Transmitter Enable */
35#define MAC_ENABLE_RX           0x00000004      /* Receiver Enable */
36
37static inline void xgmac_mac_disable(void __iomem *ioaddr)
38{
39	u32 value = readl(ioaddr + XGMAC_DMA_CONTROL);
40
41	value &= ~(DMA_CONTROL_ST | DMA_CONTROL_SR);
42	writel(value, ioaddr + XGMAC_DMA_CONTROL);
43
44	value = readl(ioaddr + XGMAC_CONTROL);
45	value &= ~(MAC_ENABLE_TX | MAC_ENABLE_RX);
46	writel(value, ioaddr + XGMAC_CONTROL);
47}
48
49static int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
50{
51	struct vfio_platform_region *reg = &vdev->regions[0];
52
53	dev_err_once(vdev->device, "DEPRECATION: VFIO Calxeda xgmac platform reset is deprecated and will be removed in a future kernel release\n");
54
55	if (!reg->ioaddr) {
56		reg->ioaddr =
57			ioremap(reg->addr, reg->size);
58		if (!reg->ioaddr)
59			return -ENOMEM;
60	}
61
62	/* disable IRQ */
63	writel(0, reg->ioaddr + XGMAC_DMA_INTR_ENA);
64
65	/* Disable the MAC core */
66	xgmac_mac_disable(reg->ioaddr);
67
68	return 0;
69}
70
71module_vfio_reset_handler("calxeda,hb-xgmac", vfio_platform_calxedaxgmac_reset);
72
73MODULE_VERSION(DRIVER_VERSION);
74MODULE_LICENSE("GPL v2");
75MODULE_AUTHOR(DRIVER_AUTHOR);
76MODULE_DESCRIPTION(DRIVER_DESC);