1 /* 2 * This program is free software; you can redistribute it and/or modify it 3 * under the terms of the GNU General Public License version 2 as published 4 * by the Free Software Foundation. 5 * 6 * Copyright (C) 2011-2015 John Crispin <blogic@phrozen.org> 7 * Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com> 8 * Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de> 9 */ 10 11 #include <linux/device.h> 12 #include <linux/err.h> 13 #include <linux/mfd/syscon.h> 14 #include <linux/module.h> 15 #include <linux/of.h> 16 #include <linux/of_platform.h> 17 #include <linux/platform_device.h> 18 #include <linux/property.h> 19 #include <linux/regmap.h> 20 21 #include <lantiq_soc.h> 22 23 #define XBAR_ALWAYS_LAST 0x430 24 #define XBAR_FPI_BURST_EN BIT(1) 25 #define XBAR_AHB_BURST_EN BIT(2) 26 27 #define RCU_VR9_BE_AHB1S 0x00000008 28 29 static int ltq_fpi_probe(struct platform_device *pdev) 30 { 31 struct device *dev = &pdev->dev; 32 struct device_node *np = dev->of_node; 33 struct resource *res_xbar; 34 struct regmap *rcu_regmap; 35 void __iomem *xbar_membase; 36 u32 rcu_ahb_endianness_reg_offset; 37 int ret; 38 39 res_xbar = platform_get_resource(pdev, IORESOURCE_MEM, 0); 40 xbar_membase = devm_ioremap_resource(dev, res_xbar); 41 if (IS_ERR(xbar_membase)) 42 return PTR_ERR(xbar_membase); 43 44 /* RCU configuration is optional */ 45 rcu_regmap = syscon_regmap_lookup_by_phandle(np, "lantiq,rcu"); 46 if (IS_ERR(rcu_regmap)) 47 return PTR_ERR(rcu_regmap); 48 49 ret = device_property_read_u32(dev, "lantiq,offset-endianness", 50 &rcu_ahb_endianness_reg_offset); 51 if (ret) { 52 dev_err(&pdev->dev, "Failed to get RCU reg offset\n"); 53 return ret; 54 } 55 56 ret = regmap_update_bits(rcu_regmap, rcu_ahb_endianness_reg_offset, 57 RCU_VR9_BE_AHB1S, RCU_VR9_BE_AHB1S); 58 if (ret) { 59 dev_warn(&pdev->dev, 60 "Failed to configure RCU AHB endianness\n"); 61 return ret; 62 } 63 64 /* disable fpi burst */ 65 ltq_w32_mask(XBAR_FPI_BURST_EN, 0, xbar_membase + XBAR_ALWAYS_LAST); 66 67 return of_platform_populate(dev->of_node, NULL, NULL, dev); 68 } 69 70 static const struct of_device_id ltq_fpi_match[] = { 71 { .compatible = "lantiq,xrx200-fpi" }, 72 {}, 73 }; 74 MODULE_DEVICE_TABLE(of, ltq_fpi_match); 75 76 static struct platform_driver ltq_fpi_driver = { 77 .probe = ltq_fpi_probe, 78 .driver = { 79 .name = "fpi-xway", 80 .of_match_table = ltq_fpi_match, 81 }, 82 }; 83 84 module_platform_driver(ltq_fpi_driver); 85 86 MODULE_DESCRIPTION("Lantiq FPI bus driver"); 87 MODULE_LICENSE("GPL"); 88