1 /* 2 * VFIO platform driver specialized for Calxeda xgmac reset 3 * reset code is inherited from calxeda xgmac native driver 4 * 5 * Copyright 2010-2011 Calxeda, Inc. 6 * Copyright (c) 2015 Linaro Ltd. 7 * www.linaro.org 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms and conditions of the GNU General Public License, 11 * version 2, as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope it will be useful, but WITHOUT 14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 16 * more details. 17 * 18 * You should have received a copy of the GNU General Public License along with 19 * this program. If not, see <http://www.gnu.org/licenses/>. 20 */ 21 22 #include <linux/module.h> 23 #include <linux/kernel.h> 24 #include <linux/init.h> 25 #include <linux/io.h> 26 27 #include "vfio_platform_private.h" 28 29 #define DRIVER_VERSION "0.1" 30 #define DRIVER_AUTHOR "Eric Auger <eric.auger@linaro.org>" 31 #define DRIVER_DESC "Reset support for Calxeda xgmac vfio platform device" 32 33 #define CALXEDAXGMAC_COMPAT "calxeda,hb-xgmac" 34 35 /* XGMAC Register definitions */ 36 #define XGMAC_CONTROL 0x00000000 /* MAC Configuration */ 37 38 /* DMA Control and Status Registers */ 39 #define XGMAC_DMA_CONTROL 0x00000f18 /* Ctrl (Operational Mode) */ 40 #define XGMAC_DMA_INTR_ENA 0x00000f1c /* Interrupt Enable */ 41 42 /* DMA Control registe defines */ 43 #define DMA_CONTROL_ST 0x00002000 /* Start/Stop Transmission */ 44 #define DMA_CONTROL_SR 0x00000002 /* Start/Stop Receive */ 45 46 /* Common MAC defines */ 47 #define MAC_ENABLE_TX 0x00000008 /* Transmitter Enable */ 48 #define MAC_ENABLE_RX 0x00000004 /* Receiver Enable */ 49 50 static inline void xgmac_mac_disable(void __iomem *ioaddr) 51 { 52 u32 value = readl(ioaddr + XGMAC_DMA_CONTROL); 53 54 value &= ~(DMA_CONTROL_ST | DMA_CONTROL_SR); 55 writel(value, ioaddr + XGMAC_DMA_CONTROL); 56 57 value = readl(ioaddr + XGMAC_CONTROL); 58 value &= ~(MAC_ENABLE_TX | MAC_ENABLE_RX); 59 writel(value, ioaddr + XGMAC_CONTROL); 60 } 61 62 int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev) 63 { 64 struct vfio_platform_region reg = vdev->regions[0]; 65 66 if (!reg.ioaddr) { 67 reg.ioaddr = 68 ioremap_nocache(reg.addr, reg.size); 69 if (!reg.ioaddr) 70 return -ENOMEM; 71 } 72 73 /* disable IRQ */ 74 writel(0, reg.ioaddr + XGMAC_DMA_INTR_ENA); 75 76 /* Disable the MAC core */ 77 xgmac_mac_disable(reg.ioaddr); 78 79 return 0; 80 } 81 EXPORT_SYMBOL_GPL(vfio_platform_calxedaxgmac_reset); 82 83 MODULE_VERSION(DRIVER_VERSION); 84 MODULE_LICENSE("GPL v2"); 85 MODULE_AUTHOR(DRIVER_AUTHOR); 86 MODULE_DESCRIPTION(DRIVER_DESC); 87