1// SPDX-License-Identifier: GPL-2.0
2/*
3 * ip30-xtalk.c - Very basic Crosstalk (XIO) detection support.
4 *   Copyright (C) 2004-2007 Stanislaw Skowronek <skylark@unaligned.org>
5 *   Copyright (C) 2009 Johannes Dickgreber <tanzy@gmx.de>
6 *   Copyright (C) 2007, 2014-2016 Joshua Kinard <kumba@gentoo.org>
7 */
8
9#include <linux/init.h>
10#include <linux/kernel.h>
11#include <linux/platform_device.h>
12#include <linux/platform_data/sgi-w1.h>
13#include <linux/platform_data/xtalk-bridge.h>
14
15#include <asm/xtalk/xwidget.h>
16#include <asm/pci/bridge.h>
17
18#define IP30_SWIN_BASE(widget) \
19		(0x0000000010000000 | (((unsigned long)(widget)) << 24))
20
21#define IP30_RAW_SWIN_BASE(widget)	(IO_BASE + IP30_SWIN_BASE(widget))
22
23#define IP30_SWIN_SIZE		(1 << 24)
24
25#define IP30_WIDGET_XBOW        _AC(0x0, UL)    /* XBow is always 0 */
26#define IP30_WIDGET_HEART       _AC(0x8, UL)    /* HEART is always 8 */
27#define IP30_WIDGET_PCI_BASE    _AC(0xf, UL)    /* BaseIO PCI is always 15 */
28
29#define XTALK_NODEV             0xffffffff
30
31#define XBOW_REG_LINK_STAT_0    0x114
32#define XBOW_REG_LINK_BLK_SIZE  0x40
33#define XBOW_REG_LINK_ALIVE     0x80000000
34
35#define HEART_INTR_ADDR		0x00000080
36
37#define xtalk_read	__raw_readl
38
39static void bridge_platform_create(int widget, int masterwid)
40{
41	struct xtalk_bridge_platform_data *bd;
42	struct sgi_w1_platform_data *wd;
43	struct platform_device *pdev_wd;
44	struct platform_device *pdev_bd;
45	struct resource w1_res;
46
47	wd = kzalloc(sizeof(*wd), GFP_KERNEL);
48	if (!wd) {
49		pr_warn("xtalk:%x bridge create out of memory\n", widget);
50		return;
51	}
52
53	snprintf(wd->dev_id, sizeof(wd->dev_id), "bridge-%012lx",
54		 IP30_SWIN_BASE(widget));
55
56	memset(&w1_res, 0, sizeof(w1_res));
57	w1_res.start = IP30_SWIN_BASE(widget) +
58				offsetof(struct bridge_regs, b_nic);
59	w1_res.end = w1_res.start + 3;
60	w1_res.flags = IORESOURCE_MEM;
61
62	pdev_wd = platform_device_alloc("sgi_w1", PLATFORM_DEVID_AUTO);
63	if (!pdev_wd) {
64		pr_warn("xtalk:%x bridge create out of memory\n", widget);
65		goto err_kfree_wd;
66	}
67	if (platform_device_add_resources(pdev_wd, &w1_res, 1)) {
68		pr_warn("xtalk:%x bridge failed to add platform resources.\n", widget);
69		goto err_put_pdev_wd;
70	}
71	if (platform_device_add_data(pdev_wd, wd, sizeof(*wd))) {
72		pr_warn("xtalk:%x bridge failed to add platform data.\n", widget);
73		goto err_put_pdev_wd;
74	}
75	if (platform_device_add(pdev_wd)) {
76		pr_warn("xtalk:%x bridge failed to add platform device.\n", widget);
77		goto err_put_pdev_wd;
78	}
79	/* platform_device_add_data() duplicates the data */
80	kfree(wd);
81
82	bd = kzalloc(sizeof(*bd), GFP_KERNEL);
83	if (!bd) {
84		pr_warn("xtalk:%x bridge create out of memory\n", widget);
85		goto err_unregister_pdev_wd;
86	}
87	pdev_bd = platform_device_alloc("xtalk-bridge", PLATFORM_DEVID_AUTO);
88	if (!pdev_bd) {
89		pr_warn("xtalk:%x bridge create out of memory\n", widget);
90		goto err_kfree_bd;
91	}
92
93	bd->bridge_addr	= IP30_RAW_SWIN_BASE(widget);
94	bd->intr_addr	= HEART_INTR_ADDR;
95	bd->nasid	= 0;
96	bd->masterwid	= masterwid;
97
98	bd->mem.name	= "Bridge PCI MEM";
99	bd->mem.start	= IP30_SWIN_BASE(widget) + BRIDGE_DEVIO0;
100	bd->mem.end	= IP30_SWIN_BASE(widget) + IP30_SWIN_SIZE - 1;
101	bd->mem.flags	= IORESOURCE_MEM;
102	bd->mem_offset	= IP30_SWIN_BASE(widget);
103
104	bd->io.name	= "Bridge PCI IO";
105	bd->io.start	= IP30_SWIN_BASE(widget) + BRIDGE_DEVIO0;
106	bd->io.end	= IP30_SWIN_BASE(widget) + IP30_SWIN_SIZE - 1;
107	bd->io.flags	= IORESOURCE_IO;
108	bd->io_offset	= IP30_SWIN_BASE(widget);
109
110	if (platform_device_add_data(pdev_bd, bd, sizeof(*bd))) {
111		pr_warn("xtalk:%x bridge failed to add platform data.\n", widget);
112		goto err_put_pdev_bd;
113	}
114	if (platform_device_add(pdev_bd)) {
115		pr_warn("xtalk:%x bridge failed to add platform device.\n", widget);
116		goto err_put_pdev_bd;
117	}
118	/* platform_device_add_data() duplicates the data */
119	kfree(bd);
120	pr_info("xtalk:%x bridge widget\n", widget);
121	return;
122
123err_put_pdev_bd:
124	platform_device_put(pdev_bd);
125err_kfree_bd:
126	kfree(bd);
127err_unregister_pdev_wd:
128	platform_device_unregister(pdev_wd);
129	return;
130err_put_pdev_wd:
131	platform_device_put(pdev_wd);
132err_kfree_wd:
133	kfree(wd);
134	return;
135}
136
137static unsigned int __init xbow_widget_active(s8 wid)
138{
139	unsigned int link_stat;
140
141	link_stat = xtalk_read((void *)(IP30_RAW_SWIN_BASE(IP30_WIDGET_XBOW) +
142					XBOW_REG_LINK_STAT_0 +
143					XBOW_REG_LINK_BLK_SIZE *
144					(wid - 8)));
145
146	return (link_stat & XBOW_REG_LINK_ALIVE) ? 1 : 0;
147}
148
149static void __init xtalk_init_widget(s8 wid, s8 masterwid)
150{
151	xwidget_part_num_t partnum;
152	widgetreg_t widget_id;
153
154	if (!xbow_widget_active(wid))
155		return;
156
157	widget_id = xtalk_read((void *)(IP30_RAW_SWIN_BASE(wid) + WIDGET_ID));
158
159	partnum = XWIDGET_PART_NUM(widget_id);
160
161	switch (partnum) {
162	case BRIDGE_WIDGET_PART_NUM:
163	case XBRIDGE_WIDGET_PART_NUM:
164		bridge_platform_create(wid, masterwid);
165		break;
166	default:
167		pr_info("xtalk:%x unknown widget (0x%x)\n", wid, partnum);
168		break;
169	}
170}
171
172static int __init ip30_xtalk_init(void)
173{
174	int i;
175
176	/*
177	 * Walk widget IDs backwards so that BaseIO is probed first.  This
178	 * ensures that the BaseIO IOC3 is always detected as eth0.
179	 */
180	for (i = IP30_WIDGET_PCI_BASE; i > IP30_WIDGET_HEART; i--)
181		xtalk_init_widget(i, IP30_WIDGET_HEART);
182
183	return 0;
184}
185
186arch_initcall(ip30_xtalk_init);
187