1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 *
 4 *  Copyright (C) 2011-2015 John Crispin <blogic@phrozen.org>
 5 *  Copyright (C) 2015 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
 6 *  Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
 7 */
 8
 9#include <linux/device.h>
10#include <linux/err.h>
11#include <linux/mfd/syscon.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/of_platform.h>
15#include <linux/platform_device.h>
16#include <linux/property.h>
17#include <linux/regmap.h>
18
19#include <lantiq_soc.h>
20
21#define XBAR_ALWAYS_LAST	0x430
22#define XBAR_FPI_BURST_EN	BIT(1)
23#define XBAR_AHB_BURST_EN	BIT(2)
24
25#define RCU_VR9_BE_AHB1S	0x00000008
26
27static int ltq_fpi_probe(struct platform_device *pdev)
28{
29	struct device *dev = &pdev->dev;
30	struct device_node *np = dev->of_node;
31	struct regmap *rcu_regmap;
32	void __iomem *xbar_membase;
33	u32 rcu_ahb_endianness_reg_offset;
34	int ret;
35
36	xbar_membase = devm_platform_ioremap_resource(pdev, 0);
37	if (IS_ERR(xbar_membase))
38		return PTR_ERR(xbar_membase);
39
40	/* RCU configuration is optional */
41	rcu_regmap = syscon_regmap_lookup_by_phandle(np, "lantiq,rcu");
42	if (IS_ERR(rcu_regmap))
43		return PTR_ERR(rcu_regmap);
44
45	ret = device_property_read_u32(dev, "lantiq,offset-endianness",
46				       &rcu_ahb_endianness_reg_offset);
47	if (ret) {
48		dev_err(&pdev->dev, "Failed to get RCU reg offset\n");
49		return ret;
50	}
51
52	ret = regmap_update_bits(rcu_regmap, rcu_ahb_endianness_reg_offset,
53				 RCU_VR9_BE_AHB1S, RCU_VR9_BE_AHB1S);
54	if (ret) {
55		dev_warn(&pdev->dev,
56			 "Failed to configure RCU AHB endianness\n");
57		return ret;
58	}
59
60	/* disable fpi burst */
61	ltq_w32_mask(XBAR_FPI_BURST_EN, 0, xbar_membase + XBAR_ALWAYS_LAST);
62
63	return of_platform_populate(dev->of_node, NULL, NULL, dev);
64}
65
66static const struct of_device_id ltq_fpi_match[] = {
67	{ .compatible = "lantiq,xrx200-fpi" },
68	{},
69};
70MODULE_DEVICE_TABLE(of, ltq_fpi_match);
71
72static struct platform_driver ltq_fpi_driver = {
73	.probe = ltq_fpi_probe,
74	.driver = {
75		.name = "fpi-xway",
76		.of_match_table = ltq_fpi_match,
77	},
78};
79
80module_platform_driver(ltq_fpi_driver);
81
82MODULE_DESCRIPTION("Lantiq FPI bus driver");
83MODULE_LICENSE("GPL");