1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * VFIO platform driver specialized for AMD xgbe reset 4 * reset code is inherited from AMD xgbe native driver 5 * 6 * Copyright (c) 2015 Linaro Ltd. 7 * www.linaro.org 8 */ 9 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/init.h> 13 #include <linux/io.h> 14 #include <uapi/linux/mdio.h> 15 #include <linux/delay.h> 16 17 #include "../vfio_platform_private.h" 18 19 #define DMA_MR 0x3000 20 #define MAC_VR 0x0110 21 #define DMA_ISR 0x3008 22 #define MAC_ISR 0x00b0 23 #define PCS_MMD_SELECT 0xff 24 #define MDIO_AN_INT 0x8002 25 #define MDIO_AN_INTMASK 0x8001 26 27 static unsigned int xmdio_read(void *ioaddr, unsigned int mmd, 28 unsigned int reg) 29 { 30 unsigned int mmd_address, value; 31 32 mmd_address = (mmd << 16) | ((reg) & 0xffff); 33 iowrite32(mmd_address >> 8, ioaddr + (PCS_MMD_SELECT << 2)); 34 value = ioread32(ioaddr + ((mmd_address & 0xff) << 2)); 35 return value; 36 } 37 38 static void xmdio_write(void *ioaddr, unsigned int mmd, 39 unsigned int reg, unsigned int value) 40 { 41 unsigned int mmd_address; 42 43 mmd_address = (mmd << 16) | ((reg) & 0xffff); 44 iowrite32(mmd_address >> 8, ioaddr + (PCS_MMD_SELECT << 2)); 45 iowrite32(value, ioaddr + ((mmd_address & 0xff) << 2)); 46 } 47 48 static int vfio_platform_amdxgbe_reset(struct vfio_platform_device *vdev) 49 { 50 struct vfio_platform_region *xgmac_regs = &vdev->regions[0]; 51 struct vfio_platform_region *xpcs_regs = &vdev->regions[1]; 52 u32 dma_mr_value, pcs_value, value; 53 unsigned int count; 54 55 if (!xgmac_regs->ioaddr) { 56 xgmac_regs->ioaddr = 57 ioremap_nocache(xgmac_regs->addr, xgmac_regs->size); 58 if (!xgmac_regs->ioaddr) 59 return -ENOMEM; 60 } 61 if (!xpcs_regs->ioaddr) { 62 xpcs_regs->ioaddr = 63 ioremap_nocache(xpcs_regs->addr, xpcs_regs->size); 64 if (!xpcs_regs->ioaddr) 65 return -ENOMEM; 66 } 67 68 /* reset the PHY through MDIO*/ 69 pcs_value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_PCS, MDIO_CTRL1); 70 pcs_value |= MDIO_CTRL1_RESET; 71 xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_PCS, MDIO_CTRL1, pcs_value); 72 73 count = 50; 74 do { 75 msleep(20); 76 pcs_value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_PCS, 77 MDIO_CTRL1); 78 } while ((pcs_value & MDIO_CTRL1_RESET) && --count); 79 80 if (pcs_value & MDIO_CTRL1_RESET) 81 dev_warn(vdev->device, "%s: XGBE PHY reset timeout\n", 82 __func__); 83 84 /* disable auto-negotiation */ 85 value = xmdio_read(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_CTRL1); 86 value &= ~MDIO_AN_CTRL1_ENABLE; 87 xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_CTRL1, value); 88 89 /* disable AN IRQ */ 90 xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_AN_INTMASK, 0); 91 92 /* clear AN IRQ */ 93 xmdio_write(xpcs_regs->ioaddr, MDIO_MMD_AN, MDIO_AN_INT, 0); 94 95 /* MAC software reset */ 96 dma_mr_value = ioread32(xgmac_regs->ioaddr + DMA_MR); 97 dma_mr_value |= 0x1; 98 iowrite32(dma_mr_value, xgmac_regs->ioaddr + DMA_MR); 99 100 usleep_range(10, 15); 101 102 count = 2000; 103 while (--count && (ioread32(xgmac_regs->ioaddr + DMA_MR) & 1)) 104 usleep_range(500, 600); 105 106 if (!count) 107 dev_warn(vdev->device, "%s: MAC SW reset failed\n", __func__); 108 109 return 0; 110 } 111 112 module_vfio_reset_handler("amd,xgbe-seattle-v1a", vfio_platform_amdxgbe_reset); 113 114 MODULE_VERSION("0.1"); 115 MODULE_LICENSE("GPL v2"); 116 MODULE_AUTHOR("Eric Auger <eric.auger@linaro.org>"); 117 MODULE_DESCRIPTION("Reset support for AMD xgbe vfio platform device"); 118