1/*
  2 * Copyright (C) 2012 CERN (www.cern.ch)
  3 * Author: Alessandro Rubini <rubini@gnudd.com>
  4 *
  5 * Released according to the GNU GPL, version 2 or any later version.
  6 *
  7 * This work is part of the White Rabbit project, a research effort led
  8 * by CERN, the European Institute for Nuclear Research.
  9 */
 10#include <linux/module.h>
 11#include <linux/slab.h>
 12#include <linux/fmc.h>
 13#include <linux/sdb.h>
 14#include <linux/err.h>
 15#include <linux/fmc-sdb.h>
 16#include <asm/byteorder.h>
 17
 18static uint32_t __sdb_rd(struct fmc_device *fmc, unsigned long address,
 19			int convert)
 20{
 21	uint32_t res = fmc_readl(fmc, address);
 22	if (convert)
 23		return __be32_to_cpu(res);
 24	return res;
 25}
 26
 27static struct sdb_array *__fmc_scan_sdb_tree(struct fmc_device *fmc,
 28					     unsigned long sdb_addr,
 29					     unsigned long reg_base, int level)
 30{
 31	uint32_t onew;
 32	int i, j, n, convert = 0;
 33	struct sdb_array *arr, *sub;
 34
 35	onew = fmc_readl(fmc, sdb_addr);
 36	if (onew == SDB_MAGIC) {
 37		/* Uh! If we are little-endian, we must convert */
 38		if (SDB_MAGIC != __be32_to_cpu(SDB_MAGIC))
 39			convert = 1;
 40	} else if (onew == __be32_to_cpu(SDB_MAGIC)) {
 41		/* ok, don't convert */
 42	} else {
 43		return ERR_PTR(-ENOENT);
 44	}
 45	/* So, the magic was there: get the count from offset 4*/
 46	onew = __sdb_rd(fmc, sdb_addr + 4, convert);
 47	n = __be16_to_cpu(*(uint16_t *)&onew);
 48	arr = kzalloc(sizeof(*arr), GFP_KERNEL);
 49	if (!arr)
 50		return ERR_PTR(-ENOMEM);
 51	arr->record = kzalloc(sizeof(arr->record[0]) * n, GFP_KERNEL);
 52	arr->subtree = kzalloc(sizeof(arr->subtree[0]) * n, GFP_KERNEL);
 53	if (!arr->record || !arr->subtree) {
 54		kfree(arr->record);
 55		kfree(arr->subtree);
 56		kfree(arr);
 57		return ERR_PTR(-ENOMEM);
 58	}
 59
 60	arr->len = n;
 61	arr->level = level;
 62	arr->fmc = fmc;
 63	for (i = 0; i < n; i++) {
 64		union  sdb_record *r;
 65
 66		for (j = 0; j < sizeof(arr->record[0]); j += 4) {
 67			*(uint32_t *)((void *)(arr->record + i) + j) =
 68				__sdb_rd(fmc, sdb_addr + (i * 64) + j, convert);
 69		}
 70		r = &arr->record[i];
 71		arr->subtree[i] = ERR_PTR(-ENODEV);
 72		if (r->empty.record_type == sdb_type_bridge) {
 73			struct sdb_component *c = &r->bridge.sdb_component;
 74			uint64_t subaddr = __be64_to_cpu(r->bridge.sdb_child);
 75			uint64_t newbase = __be64_to_cpu(c->addr_first);
 76
 77			subaddr += reg_base;
 78			newbase += reg_base;
 79			sub = __fmc_scan_sdb_tree(fmc, subaddr, newbase,
 80						  level + 1);
 81			arr->subtree[i] = sub; /* may be error */
 82			if (IS_ERR(sub))
 83				continue;
 84			sub->parent = arr;
 85			sub->baseaddr = newbase;
 86		}
 87	}
 88	return arr;
 89}
 90
 91int fmc_scan_sdb_tree(struct fmc_device *fmc, unsigned long address)
 92{
 93	struct sdb_array *ret;
 94	if (fmc->sdb)
 95		return -EBUSY;
 96	ret = __fmc_scan_sdb_tree(fmc, address, 0 /* regs */, 0);
 97	if (IS_ERR(ret))
 98		return PTR_ERR(ret);
 99	fmc->sdb = ret;
100	return 0;
101}
102EXPORT_SYMBOL(fmc_scan_sdb_tree);
103
104static void __fmc_sdb_free(struct sdb_array *arr)
105{
106	int i, n;
107
108	if (!arr)
109		return;
110	n = arr->len;
111	for (i = 0; i < n; i++) {
112		if (IS_ERR(arr->subtree[i]))
113			continue;
114		__fmc_sdb_free(arr->subtree[i]);
115	}
116	kfree(arr->record);
117	kfree(arr->subtree);
118	kfree(arr);
119}
120
121int fmc_free_sdb_tree(struct fmc_device *fmc)
122{
123	__fmc_sdb_free(fmc->sdb);
124	fmc->sdb = NULL;
125	return 0;
126}
127EXPORT_SYMBOL(fmc_free_sdb_tree);
128
129/* This helper calls reprogram and inizialized sdb as well */
130int fmc_reprogram_raw(struct fmc_device *fmc, struct fmc_driver *d,
131		      void *gw, unsigned long len, int sdb_entry)
132{
133	int ret;
134
135	ret = fmc->op->reprogram_raw(fmc, d, gw, len);
136	if (ret < 0)
137		return ret;
138	if (sdb_entry < 0)
139		return ret;
140
141	/* We are required to find SDB at a given offset */
142	ret = fmc_scan_sdb_tree(fmc, sdb_entry);
143	if (ret < 0) {
144		dev_err(&fmc->dev, "Can't find SDB at address 0x%x\n",
145			sdb_entry);
146		return -ENODEV;
147	}
148
149	return 0;
150}
151EXPORT_SYMBOL(fmc_reprogram_raw);
152
153/* This helper calls reprogram and inizialized sdb as well */
154int fmc_reprogram(struct fmc_device *fmc, struct fmc_driver *d, char *gw,
155			 int sdb_entry)
156{
157	int ret;
158
159	ret = fmc->op->reprogram(fmc, d, gw);
160	if (ret < 0)
161		return ret;
162	if (sdb_entry < 0)
163		return ret;
164
165	/* We are required to find SDB at a given offset */
166	ret = fmc_scan_sdb_tree(fmc, sdb_entry);
167	if (ret < 0) {
168		dev_err(&fmc->dev, "Can't find SDB at address 0x%x\n",
169			sdb_entry);
170		return -ENODEV;
171	}
172
173	return 0;
174}
175EXPORT_SYMBOL(fmc_reprogram);
176
177void fmc_show_sdb_tree(const struct fmc_device *fmc)
178{
179	pr_err("%s: not supported anymore, use debugfs to dump SDB\n",
180		__func__);
181}
182EXPORT_SYMBOL(fmc_show_sdb_tree);
183
184signed long fmc_find_sdb_device(struct sdb_array *tree,
185				uint64_t vid, uint32_t did, unsigned long *sz)
186{
187	signed long res = -ENODEV;
188	union  sdb_record *r;
189	struct sdb_product *p;
190	struct sdb_component *c;
191	int i, n = tree->len;
192	uint64_t last, first;
193
194	/* FIXME: what if the first interconnect is not at zero? */
195	for (i = 0; i < n; i++) {
196		r = &tree->record[i];
197		c = &r->dev.sdb_component;
198		p = &c->product;
199
200		if (!IS_ERR(tree->subtree[i]))
201			res = fmc_find_sdb_device(tree->subtree[i],
202						  vid, did, sz);
203		if (res >= 0)
204			return res + tree->baseaddr;
205		if (r->empty.record_type != sdb_type_device)
206			continue;
207		if (__be64_to_cpu(p->vendor_id) != vid)
208			continue;
209		if (__be32_to_cpu(p->device_id) != did)
210			continue;
211		/* found */
212		last = __be64_to_cpu(c->addr_last);
213		first = __be64_to_cpu(c->addr_first);
214		if (sz)
215			*sz = (typeof(*sz))(last + 1 - first);
216		return first + tree->baseaddr;
217	}
218	return res;
219}
220EXPORT_SYMBOL(fmc_find_sdb_device);