1 /* 2 * Technologic Systems TS-73xx SBC FPGA loader 3 * 4 * Copyright (C) 2016 Florian Fainelli <f.fainelli@gmail.com> 5 * 6 * FPGA Manager Driver for the on-board Altera Cyclone II FPGA found on 7 * TS-7300, heavily based on load_fpga.c in their vendor tree. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; version 2 of the License. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 */ 18 19 #include <linux/delay.h> 20 #include <linux/io.h> 21 #include <linux/module.h> 22 #include <linux/platform_device.h> 23 #include <linux/string.h> 24 #include <linux/iopoll.h> 25 #include <linux/fpga/fpga-mgr.h> 26 27 #define TS73XX_FPGA_DATA_REG 0 28 #define TS73XX_FPGA_CONFIG_REG 1 29 30 #define TS73XX_FPGA_WRITE_DONE 0x1 31 #define TS73XX_FPGA_WRITE_DONE_TIMEOUT 1000 /* us */ 32 #define TS73XX_FPGA_RESET 0x2 33 #define TS73XX_FPGA_RESET_LOW_DELAY 30 /* us */ 34 #define TS73XX_FPGA_RESET_HIGH_DELAY 80 /* us */ 35 #define TS73XX_FPGA_LOAD_OK 0x4 36 #define TS73XX_FPGA_CONFIG_LOAD 0x8 37 38 struct ts73xx_fpga_priv { 39 void __iomem *io_base; 40 struct device *dev; 41 }; 42 43 static enum fpga_mgr_states ts73xx_fpga_state(struct fpga_manager *mgr) 44 { 45 return FPGA_MGR_STATE_UNKNOWN; 46 } 47 48 static int ts73xx_fpga_write_init(struct fpga_manager *mgr, 49 struct fpga_image_info *info, 50 const char *buf, size_t count) 51 { 52 struct ts73xx_fpga_priv *priv = mgr->priv; 53 54 /* Reset the FPGA */ 55 writeb(0, priv->io_base + TS73XX_FPGA_CONFIG_REG); 56 udelay(TS73XX_FPGA_RESET_LOW_DELAY); 57 writeb(TS73XX_FPGA_RESET, priv->io_base + TS73XX_FPGA_CONFIG_REG); 58 udelay(TS73XX_FPGA_RESET_HIGH_DELAY); 59 60 return 0; 61 } 62 63 static int ts73xx_fpga_write(struct fpga_manager *mgr, const char *buf, 64 size_t count) 65 { 66 struct ts73xx_fpga_priv *priv = mgr->priv; 67 size_t i = 0; 68 int ret; 69 u8 reg; 70 71 while (count--) { 72 ret = readb_poll_timeout(priv->io_base + TS73XX_FPGA_CONFIG_REG, 73 reg, !(reg & TS73XX_FPGA_WRITE_DONE), 74 1, TS73XX_FPGA_WRITE_DONE_TIMEOUT); 75 if (ret < 0) 76 return ret; 77 78 writeb(buf[i], priv->io_base + TS73XX_FPGA_DATA_REG); 79 i++; 80 } 81 82 return 0; 83 } 84 85 static int ts73xx_fpga_write_complete(struct fpga_manager *mgr, 86 struct fpga_image_info *info) 87 { 88 struct ts73xx_fpga_priv *priv = mgr->priv; 89 u8 reg; 90 91 usleep_range(1000, 2000); 92 reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); 93 reg |= TS73XX_FPGA_CONFIG_LOAD; 94 writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); 95 96 usleep_range(1000, 2000); 97 reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); 98 reg &= ~TS73XX_FPGA_CONFIG_LOAD; 99 writeb(reg, priv->io_base + TS73XX_FPGA_CONFIG_REG); 100 101 reg = readb(priv->io_base + TS73XX_FPGA_CONFIG_REG); 102 if ((reg & TS73XX_FPGA_LOAD_OK) != TS73XX_FPGA_LOAD_OK) 103 return -ETIMEDOUT; 104 105 return 0; 106 } 107 108 static const struct fpga_manager_ops ts73xx_fpga_ops = { 109 .state = ts73xx_fpga_state, 110 .write_init = ts73xx_fpga_write_init, 111 .write = ts73xx_fpga_write, 112 .write_complete = ts73xx_fpga_write_complete, 113 }; 114 115 static int ts73xx_fpga_probe(struct platform_device *pdev) 116 { 117 struct device *kdev = &pdev->dev; 118 struct ts73xx_fpga_priv *priv; 119 struct fpga_manager *mgr; 120 struct resource *res; 121 int ret; 122 123 priv = devm_kzalloc(kdev, sizeof(*priv), GFP_KERNEL); 124 if (!priv) 125 return -ENOMEM; 126 127 priv->dev = kdev; 128 129 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 130 priv->io_base = devm_ioremap_resource(kdev, res); 131 if (IS_ERR(priv->io_base)) { 132 dev_err(kdev, "unable to remap registers\n"); 133 return PTR_ERR(priv->io_base); 134 } 135 136 mgr = fpga_mgr_create(kdev, "TS-73xx FPGA Manager", 137 &ts73xx_fpga_ops, priv); 138 if (!mgr) 139 return -ENOMEM; 140 141 platform_set_drvdata(pdev, mgr); 142 143 ret = fpga_mgr_register(mgr); 144 if (ret) 145 fpga_mgr_free(mgr); 146 147 return ret; 148 } 149 150 static int ts73xx_fpga_remove(struct platform_device *pdev) 151 { 152 struct fpga_manager *mgr = platform_get_drvdata(pdev); 153 154 fpga_mgr_unregister(mgr); 155 156 return 0; 157 } 158 159 static struct platform_driver ts73xx_fpga_driver = { 160 .driver = { 161 .name = "ts73xx-fpga-mgr", 162 }, 163 .probe = ts73xx_fpga_probe, 164 .remove = ts73xx_fpga_remove, 165 }; 166 module_platform_driver(ts73xx_fpga_driver); 167 168 MODULE_AUTHOR("Florian Fainelli <f.fainelli@gmail.com>"); 169 MODULE_DESCRIPTION("TS-73xx FPGA Manager driver"); 170 MODULE_LICENSE("GPL v2"); 171