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 xgmac_mac_disable(void __iomem * ioaddr)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 vfio_platform_calxedaxgmac_reset(struct vfio_platform_device * vdev)49static int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev) 50 { 51 struct vfio_platform_region *reg = &vdev->regions[0]; 52 53 if (!reg->ioaddr) { 54 reg->ioaddr = 55 ioremap(reg->addr, reg->size); 56 if (!reg->ioaddr) 57 return -ENOMEM; 58 } 59 60 /* disable IRQ */ 61 writel(0, reg->ioaddr + XGMAC_DMA_INTR_ENA); 62 63 /* Disable the MAC core */ 64 xgmac_mac_disable(reg->ioaddr); 65 66 return 0; 67 } 68 69 module_vfio_reset_handler("calxeda,hb-xgmac", vfio_platform_calxedaxgmac_reset); 70 71 MODULE_VERSION(DRIVER_VERSION); 72 MODULE_LICENSE("GPL v2"); 73 MODULE_AUTHOR(DRIVER_AUTHOR); 74 MODULE_DESCRIPTION(DRIVER_DESC); 75