1/*
2 *  Cobalt NOR flash functions
3 *
4 *  Copyright 2012-2015 Cisco Systems, Inc. and/or its affiliates.
5 *  All rights reserved.
6 *
7 *  This program is free software; you may redistribute it and/or modify
8 *  it under the terms of the GNU General Public License as published by
9 *  the Free Software Foundation; version 2 of the License.
10 *
11 *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
12 *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
13 *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
14 *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
15 *  BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
16 *  ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
17 *  CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
18 *  SOFTWARE.
19 */
20
21#include <linux/mtd/mtd.h>
22#include <linux/mtd/map.h>
23#include <linux/mtd/cfi.h>
24#include <linux/time.h>
25
26#include "cobalt-flash.h"
27
28#define ADRS(offset) (COBALT_BUS_FLASH_BASE + offset)
29
30static struct map_info cobalt_flash_map = {
31	.name =		"cobalt-flash",
32	.bankwidth =	2,         /* 16 bits */
33	.size =		0x4000000, /* 64MB */
34	.phys =		0,         /* offset  */
35};
36
37static map_word flash_read16(struct map_info *map, unsigned long offset)
38{
39	map_word r;
40
41	r.x[0] = cobalt_bus_read32(map->virt, ADRS(offset));
42	if (offset & 0x2)
43		r.x[0] >>= 16;
44	else
45		r.x[0] &= 0x0000ffff;
46
47	return r;
48}
49
50static void flash_write16(struct map_info *map, const map_word datum,
51			  unsigned long offset)
52{
53	u16 data = (u16)datum.x[0];
54
55	cobalt_bus_write16(map->virt, ADRS(offset), data);
56}
57
58static void flash_copy_from(struct map_info *map, void *to,
59			    unsigned long from, ssize_t len)
60{
61	u32 src = from;
62	u8 *dest = to;
63	u32 data;
64
65	while (len) {
66		data = cobalt_bus_read32(map->virt, ADRS(src));
67		do {
68			*dest = data >> (8 * (src & 3));
69			src++;
70			dest++;
71			len--;
72		} while (len && (src % 4));
73	}
74}
75
76static void flash_copy_to(struct map_info *map, unsigned long to,
77			  const void *from, ssize_t len)
78{
79	const u8 *src = from;
80	u32 dest = to;
81
82	pr_info("%s: offset 0x%x: length %zu\n", __func__, dest, len);
83	while (len) {
84		u16 data = 0xffff;
85
86		do {
87			data = *src << (8 * (dest & 1));
88			src++;
89			dest++;
90			len--;
91		} while (len && (dest % 2));
92
93		cobalt_bus_write16(map->virt, ADRS(dest - 2), data);
94	}
95}
96
97int cobalt_flash_probe(struct cobalt *cobalt)
98{
99	struct map_info *map = &cobalt_flash_map;
100	struct mtd_info *mtd;
101
102	BUG_ON(!map_bankwidth_supported(map->bankwidth));
103	map->virt = cobalt->bar1;
104	map->read = flash_read16;
105	map->write = flash_write16;
106	map->copy_from = flash_copy_from;
107	map->copy_to = flash_copy_to;
108
109	mtd = do_map_probe("cfi_probe", map);
110	cobalt->mtd = mtd;
111	if (!mtd) {
112		cobalt_err("Probe CFI flash failed!\n");
113		return -1;
114	}
115
116	mtd->owner = THIS_MODULE;
117	mtd->dev.parent = &cobalt->pci_dev->dev;
118	mtd_device_register(mtd, NULL, 0);
119	return 0;
120}
121
122void cobalt_flash_remove(struct cobalt *cobalt)
123{
124	if (cobalt->mtd) {
125		mtd_device_unregister(cobalt->mtd);
126		map_destroy(cobalt->mtd);
127	}
128}
129