1/*
2 * (c) Copyright 2006 Benjamin Herrenschmidt, IBM Corp.
3 *                    <benh@kernel.crashing.org>
4 *
5 *   This program is free software;  you can redistribute it and/or modify
6 *   it under the terms of the GNU General Public License as published by
7 *   the Free Software Foundation; either version 2 of the License, or
8 *   (at your option) any later version.
9 *
10 *   This program is distributed in the hope that it will be useful,
11 *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
13 *   the GNU General Public License for more details.
14 *
15 *   You should have received a copy of the GNU General Public License
16 *   along with this program;  if not, write to the Free Software
17 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18 */
19
20#undef DEBUG
21
22#include <linux/kernel.h>
23#include <linux/export.h>
24#include <asm/prom.h>
25#include <asm/dcr.h>
26
27#ifdef CONFIG_PPC_DCR_MMIO
28static struct device_node *find_dcr_parent(struct device_node *node)
29{
30	struct device_node *par, *tmp;
31	const u32 *p;
32
33	for (par = of_node_get(node); par;) {
34		if (of_get_property(par, "dcr-controller", NULL))
35			break;
36		p = of_get_property(par, "dcr-parent", NULL);
37		tmp = par;
38		if (p == NULL)
39			par = of_get_parent(par);
40		else
41			par = of_find_node_by_phandle(*p);
42		of_node_put(tmp);
43	}
44	return par;
45}
46#endif
47
48#if defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO)
49
50bool dcr_map_ok_generic(dcr_host_t host)
51{
52	if (host.type == DCR_HOST_NATIVE)
53		return dcr_map_ok_native(host.host.native);
54	else if (host.type == DCR_HOST_MMIO)
55		return dcr_map_ok_mmio(host.host.mmio);
56	else
57		return false;
58}
59EXPORT_SYMBOL_GPL(dcr_map_ok_generic);
60
61dcr_host_t dcr_map_generic(struct device_node *dev,
62			   unsigned int dcr_n,
63			   unsigned int dcr_c)
64{
65	dcr_host_t host;
66	struct device_node *dp;
67	const char *prop;
68
69	host.type = DCR_HOST_INVALID;
70
71	dp = find_dcr_parent(dev);
72	if (dp == NULL)
73		return host;
74
75	prop = of_get_property(dp, "dcr-access-method", NULL);
76
77	pr_debug("dcr_map_generic(dcr-access-method = %s)\n", prop);
78
79	if (!strcmp(prop, "native")) {
80		host.type = DCR_HOST_NATIVE;
81		host.host.native = dcr_map_native(dev, dcr_n, dcr_c);
82	} else if (!strcmp(prop, "mmio")) {
83		host.type = DCR_HOST_MMIO;
84		host.host.mmio = dcr_map_mmio(dev, dcr_n, dcr_c);
85	}
86
87	of_node_put(dp);
88	return host;
89}
90EXPORT_SYMBOL_GPL(dcr_map_generic);
91
92void dcr_unmap_generic(dcr_host_t host, unsigned int dcr_c)
93{
94	if (host.type == DCR_HOST_NATIVE)
95		dcr_unmap_native(host.host.native, dcr_c);
96	else if (host.type == DCR_HOST_MMIO)
97		dcr_unmap_mmio(host.host.mmio, dcr_c);
98	else /* host.type == DCR_HOST_INVALID */
99		WARN_ON(true);
100}
101EXPORT_SYMBOL_GPL(dcr_unmap_generic);
102
103u32 dcr_read_generic(dcr_host_t host, unsigned int dcr_n)
104{
105	if (host.type == DCR_HOST_NATIVE)
106		return dcr_read_native(host.host.native, dcr_n);
107	else if (host.type == DCR_HOST_MMIO)
108		return dcr_read_mmio(host.host.mmio, dcr_n);
109	else /* host.type == DCR_HOST_INVALID */
110		WARN_ON(true);
111	return 0;
112}
113EXPORT_SYMBOL_GPL(dcr_read_generic);
114
115void dcr_write_generic(dcr_host_t host, unsigned int dcr_n, u32 value)
116{
117	if (host.type == DCR_HOST_NATIVE)
118		dcr_write_native(host.host.native, dcr_n, value);
119	else if (host.type == DCR_HOST_MMIO)
120		dcr_write_mmio(host.host.mmio, dcr_n, value);
121	else /* host.type == DCR_HOST_INVALID */
122		WARN_ON(true);
123}
124EXPORT_SYMBOL_GPL(dcr_write_generic);
125
126#endif /* defined(CONFIG_PPC_DCR_NATIVE) && defined(CONFIG_PPC_DCR_MMIO) */
127
128unsigned int dcr_resource_start(const struct device_node *np,
129				unsigned int index)
130{
131	unsigned int ds;
132	const u32 *dr = of_get_property(np, "dcr-reg", &ds);
133
134	if (dr == NULL || ds & 1 || index >= (ds / 8))
135		return 0;
136
137	return dr[index * 2];
138}
139EXPORT_SYMBOL_GPL(dcr_resource_start);
140
141unsigned int dcr_resource_len(const struct device_node *np, unsigned int index)
142{
143	unsigned int ds;
144	const u32 *dr = of_get_property(np, "dcr-reg", &ds);
145
146	if (dr == NULL || ds & 1 || index >= (ds / 8))
147		return 0;
148
149	return dr[index * 2 + 1];
150}
151EXPORT_SYMBOL_GPL(dcr_resource_len);
152
153#ifdef CONFIG_PPC_DCR_MMIO
154
155static u64 of_translate_dcr_address(struct device_node *dev,
156				    unsigned int dcr_n,
157				    unsigned int *out_stride)
158{
159	struct device_node *dp;
160	const u32 *p;
161	unsigned int stride;
162	u64 ret = OF_BAD_ADDR;
163
164	dp = find_dcr_parent(dev);
165	if (dp == NULL)
166		return OF_BAD_ADDR;
167
168	/* Stride is not properly defined yet, default to 0x10 for Axon */
169	p = of_get_property(dp, "dcr-mmio-stride", NULL);
170	stride = (p == NULL) ? 0x10 : *p;
171
172	/* XXX FIXME: Which property name is to use of the 2 following ? */
173	p = of_get_property(dp, "dcr-mmio-range", NULL);
174	if (p == NULL)
175		p = of_get_property(dp, "dcr-mmio-space", NULL);
176	if (p == NULL)
177		goto done;
178
179	/* Maybe could do some better range checking here */
180	ret = of_translate_address(dp, p);
181	if (ret != OF_BAD_ADDR)
182		ret += (u64)(stride) * (u64)dcr_n;
183	if (out_stride)
184		*out_stride = stride;
185
186 done:
187	of_node_put(dp);
188	return ret;
189}
190
191dcr_host_mmio_t dcr_map_mmio(struct device_node *dev,
192			     unsigned int dcr_n,
193			     unsigned int dcr_c)
194{
195	dcr_host_mmio_t ret = { .token = NULL, .stride = 0, .base = dcr_n };
196	u64 addr;
197
198	pr_debug("dcr_map(%s, 0x%x, 0x%x)\n",
199		 dev->full_name, dcr_n, dcr_c);
200
201	addr = of_translate_dcr_address(dev, dcr_n, &ret.stride);
202	pr_debug("translates to addr: 0x%llx, stride: 0x%x\n",
203		 (unsigned long long) addr, ret.stride);
204	if (addr == OF_BAD_ADDR)
205		return ret;
206	pr_debug("mapping 0x%x bytes\n", dcr_c * ret.stride);
207	ret.token = ioremap(addr, dcr_c * ret.stride);
208	if (ret.token == NULL)
209		return ret;
210	pr_debug("mapped at 0x%p -> base is 0x%p\n",
211		 ret.token, ret.token - dcr_n * ret.stride);
212	ret.token -= dcr_n * ret.stride;
213	return ret;
214}
215EXPORT_SYMBOL_GPL(dcr_map_mmio);
216
217void dcr_unmap_mmio(dcr_host_mmio_t host, unsigned int dcr_c)
218{
219	dcr_host_mmio_t h = host;
220
221	if (h.token == NULL)
222		return;
223	h.token += host.base * h.stride;
224	iounmap(h.token);
225	h.token = NULL;
226}
227EXPORT_SYMBOL_GPL(dcr_unmap_mmio);
228
229#endif /* defined(CONFIG_PPC_DCR_MMIO) */
230
231#ifdef CONFIG_PPC_DCR_NATIVE
232DEFINE_SPINLOCK(dcr_ind_lock);
233EXPORT_SYMBOL_GPL(dcr_ind_lock);
234#endif	/* defined(CONFIG_PPC_DCR_NATIVE) */
235
236