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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Marvell EBU SoC Device Bus Controller
4 * (memory controller for NOR/NAND/SRAM/FPGA devices)
5 *
6 * Copyright (C) 2013-2014 Marvell
7 */
8
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/err.h>
13#include <linux/io.h>
14#include <linux/clk.h>
15#include <linux/mbus.h>
16#include <linux/of_platform.h>
17#include <linux/of_address.h>
18#include <linux/platform_device.h>
19
20/* Register definitions */
21#define ARMADA_DEV_WIDTH_SHIFT 30
22#define ARMADA_BADR_SKEW_SHIFT 28
23#define ARMADA_RD_HOLD_SHIFT 23
24#define ARMADA_ACC_NEXT_SHIFT 17
25#define ARMADA_RD_SETUP_SHIFT 12
26#define ARMADA_ACC_FIRST_SHIFT 6
27
28#define ARMADA_SYNC_ENABLE_SHIFT 24
29#define ARMADA_WR_HIGH_SHIFT 16
30#define ARMADA_WR_LOW_SHIFT 8
31
32#define ARMADA_READ_PARAM_OFFSET 0x0
33#define ARMADA_WRITE_PARAM_OFFSET 0x4
34
35#define ORION_RESERVED (0x2 << 30)
36#define ORION_BADR_SKEW_SHIFT 28
37#define ORION_WR_HIGH_EXT_BIT BIT(27)
38#define ORION_WR_HIGH_EXT_MASK 0x8
39#define ORION_WR_LOW_EXT_BIT BIT(26)
40#define ORION_WR_LOW_EXT_MASK 0x8
41#define ORION_ALE_WR_EXT_BIT BIT(25)
42#define ORION_ALE_WR_EXT_MASK 0x8
43#define ORION_ACC_NEXT_EXT_BIT BIT(24)
44#define ORION_ACC_NEXT_EXT_MASK 0x10
45#define ORION_ACC_FIRST_EXT_BIT BIT(23)
46#define ORION_ACC_FIRST_EXT_MASK 0x10
47#define ORION_TURN_OFF_EXT_BIT BIT(22)
48#define ORION_TURN_OFF_EXT_MASK 0x8
49#define ORION_DEV_WIDTH_SHIFT 20
50#define ORION_WR_HIGH_SHIFT 17
51#define ORION_WR_HIGH_MASK 0x7
52#define ORION_WR_LOW_SHIFT 14
53#define ORION_WR_LOW_MASK 0x7
54#define ORION_ALE_WR_SHIFT 11
55#define ORION_ALE_WR_MASK 0x7
56#define ORION_ACC_NEXT_SHIFT 7
57#define ORION_ACC_NEXT_MASK 0xF
58#define ORION_ACC_FIRST_SHIFT 3
59#define ORION_ACC_FIRST_MASK 0xF
60#define ORION_TURN_OFF_SHIFT 0
61#define ORION_TURN_OFF_MASK 0x7
62
63struct devbus_read_params {
64 u32 bus_width;
65 u32 badr_skew;
66 u32 turn_off;
67 u32 acc_first;
68 u32 acc_next;
69 u32 rd_setup;
70 u32 rd_hold;
71};
72
73struct devbus_write_params {
74 u32 sync_enable;
75 u32 wr_high;
76 u32 wr_low;
77 u32 ale_wr;
78};
79
80struct devbus {
81 struct device *dev;
82 void __iomem *base;
83 unsigned long tick_ps;
84};
85
86static int get_timing_param_ps(struct devbus *devbus,
87 struct device_node *node,
88 const char *name,
89 u32 *ticks)
90{
91 u32 time_ps;
92 int err;
93
94 err = of_property_read_u32(node, name, &time_ps);
95 if (err < 0) {
96 dev_err(devbus->dev, "%pOF has no '%s' property\n",
97 node, name);
98 return err;
99 }
100
101 *ticks = (time_ps + devbus->tick_ps - 1) / devbus->tick_ps;
102
103 dev_dbg(devbus->dev, "%s: %u ps -> 0x%x\n",
104 name, time_ps, *ticks);
105 return 0;
106}
107
108static int devbus_get_timing_params(struct devbus *devbus,
109 struct device_node *node,
110 struct devbus_read_params *r,
111 struct devbus_write_params *w)
112{
113 int err;
114
115 err = of_property_read_u32(node, "devbus,bus-width", &r->bus_width);
116 if (err < 0) {
117 dev_err(devbus->dev,
118 "%pOF has no 'devbus,bus-width' property\n",
119 node);
120 return err;
121 }
122
123 /*
124 * The bus width is encoded into the register as 0 for 8 bits,
125 * and 1 for 16 bits, so we do the necessary conversion here.
126 */
127 if (r->bus_width == 8) {
128 r->bus_width = 0;
129 } else if (r->bus_width == 16) {
130 r->bus_width = 1;
131 } else {
132 dev_err(devbus->dev, "invalid bus width %d\n", r->bus_width);
133 return -EINVAL;
134 }
135
136 err = get_timing_param_ps(devbus, node, "devbus,badr-skew-ps",
137 &r->badr_skew);
138 if (err < 0)
139 return err;
140
141 err = get_timing_param_ps(devbus, node, "devbus,turn-off-ps",
142 &r->turn_off);
143 if (err < 0)
144 return err;
145
146 err = get_timing_param_ps(devbus, node, "devbus,acc-first-ps",
147 &r->acc_first);
148 if (err < 0)
149 return err;
150
151 err = get_timing_param_ps(devbus, node, "devbus,acc-next-ps",
152 &r->acc_next);
153 if (err < 0)
154 return err;
155
156 if (of_device_is_compatible(devbus->dev->of_node, "marvell,mvebu-devbus")) {
157 err = get_timing_param_ps(devbus, node, "devbus,rd-setup-ps",
158 &r->rd_setup);
159 if (err < 0)
160 return err;
161
162 err = get_timing_param_ps(devbus, node, "devbus,rd-hold-ps",
163 &r->rd_hold);
164 if (err < 0)
165 return err;
166
167 err = of_property_read_u32(node, "devbus,sync-enable",
168 &w->sync_enable);
169 if (err < 0) {
170 dev_err(devbus->dev,
171 "%pOF has no 'devbus,sync-enable' property\n",
172 node);
173 return err;
174 }
175 }
176
177 err = get_timing_param_ps(devbus, node, "devbus,ale-wr-ps",
178 &w->ale_wr);
179 if (err < 0)
180 return err;
181
182 err = get_timing_param_ps(devbus, node, "devbus,wr-low-ps",
183 &w->wr_low);
184 if (err < 0)
185 return err;
186
187 err = get_timing_param_ps(devbus, node, "devbus,wr-high-ps",
188 &w->wr_high);
189 if (err < 0)
190 return err;
191
192 return 0;
193}
194
195static void devbus_orion_set_timing_params(struct devbus *devbus,
196 struct device_node *node,
197 struct devbus_read_params *r,
198 struct devbus_write_params *w)
199{
200 u32 value;
201
202 /*
203 * The hardware designers found it would be a good idea to
204 * split most of the values in the register into two fields:
205 * one containing all the low-order bits, and another one
206 * containing just the high-order bit. For all of those
207 * fields, we have to split the value into these two parts.
208 */
209 value = (r->turn_off & ORION_TURN_OFF_MASK) << ORION_TURN_OFF_SHIFT |
210 (r->acc_first & ORION_ACC_FIRST_MASK) << ORION_ACC_FIRST_SHIFT |
211 (r->acc_next & ORION_ACC_NEXT_MASK) << ORION_ACC_NEXT_SHIFT |
212 (w->ale_wr & ORION_ALE_WR_MASK) << ORION_ALE_WR_SHIFT |
213 (w->wr_low & ORION_WR_LOW_MASK) << ORION_WR_LOW_SHIFT |
214 (w->wr_high & ORION_WR_HIGH_MASK) << ORION_WR_HIGH_SHIFT |
215 r->bus_width << ORION_DEV_WIDTH_SHIFT |
216 ((r->turn_off & ORION_TURN_OFF_EXT_MASK) ? ORION_TURN_OFF_EXT_BIT : 0) |
217 ((r->acc_first & ORION_ACC_FIRST_EXT_MASK) ? ORION_ACC_FIRST_EXT_BIT : 0) |
218 ((r->acc_next & ORION_ACC_NEXT_EXT_MASK) ? ORION_ACC_NEXT_EXT_BIT : 0) |
219 ((w->ale_wr & ORION_ALE_WR_EXT_MASK) ? ORION_ALE_WR_EXT_BIT : 0) |
220 ((w->wr_low & ORION_WR_LOW_EXT_MASK) ? ORION_WR_LOW_EXT_BIT : 0) |
221 ((w->wr_high & ORION_WR_HIGH_EXT_MASK) ? ORION_WR_HIGH_EXT_BIT : 0) |
222 (r->badr_skew << ORION_BADR_SKEW_SHIFT) |
223 ORION_RESERVED;
224
225 writel(value, devbus->base);
226}
227
228static void devbus_armada_set_timing_params(struct devbus *devbus,
229 struct device_node *node,
230 struct devbus_read_params *r,
231 struct devbus_write_params *w)
232{
233 u32 value;
234
235 /* Set read timings */
236 value = r->bus_width << ARMADA_DEV_WIDTH_SHIFT |
237 r->badr_skew << ARMADA_BADR_SKEW_SHIFT |
238 r->rd_hold << ARMADA_RD_HOLD_SHIFT |
239 r->acc_next << ARMADA_ACC_NEXT_SHIFT |
240 r->rd_setup << ARMADA_RD_SETUP_SHIFT |
241 r->acc_first << ARMADA_ACC_FIRST_SHIFT |
242 r->turn_off;
243
244 dev_dbg(devbus->dev, "read parameters register 0x%p = 0x%x\n",
245 devbus->base + ARMADA_READ_PARAM_OFFSET,
246 value);
247
248 writel(value, devbus->base + ARMADA_READ_PARAM_OFFSET);
249
250 /* Set write timings */
251 value = w->sync_enable << ARMADA_SYNC_ENABLE_SHIFT |
252 w->wr_low << ARMADA_WR_LOW_SHIFT |
253 w->wr_high << ARMADA_WR_HIGH_SHIFT |
254 w->ale_wr;
255
256 dev_dbg(devbus->dev, "write parameters register: 0x%p = 0x%x\n",
257 devbus->base + ARMADA_WRITE_PARAM_OFFSET,
258 value);
259
260 writel(value, devbus->base + ARMADA_WRITE_PARAM_OFFSET);
261}
262
263static int mvebu_devbus_probe(struct platform_device *pdev)
264{
265 struct device *dev = &pdev->dev;
266 struct device_node *node = pdev->dev.of_node;
267 struct devbus_read_params r;
268 struct devbus_write_params w;
269 struct devbus *devbus;
270 struct clk *clk;
271 unsigned long rate;
272 int err;
273
274 devbus = devm_kzalloc(&pdev->dev, sizeof(struct devbus), GFP_KERNEL);
275 if (!devbus)
276 return -ENOMEM;
277
278 devbus->dev = dev;
279 devbus->base = devm_platform_ioremap_resource(pdev, 0);
280 if (IS_ERR(devbus->base))
281 return PTR_ERR(devbus->base);
282
283 clk = devm_clk_get_enabled(&pdev->dev, NULL);
284 if (IS_ERR(clk))
285 return PTR_ERR(clk);
286
287 /*
288 * Obtain clock period in picoseconds,
289 * we need this in order to convert timing
290 * parameters from cycles to picoseconds.
291 */
292 rate = clk_get_rate(clk) / 1000;
293 devbus->tick_ps = 1000000000 / rate;
294
295 dev_dbg(devbus->dev, "Setting timing parameter, tick is %lu ps\n",
296 devbus->tick_ps);
297
298 if (!of_property_read_bool(node, "devbus,keep-config")) {
299 /* Read the Device Tree node */
300 err = devbus_get_timing_params(devbus, node, &r, &w);
301 if (err < 0)
302 return err;
303
304 /* Set the new timing parameters */
305 if (of_device_is_compatible(node, "marvell,orion-devbus"))
306 devbus_orion_set_timing_params(devbus, node, &r, &w);
307 else
308 devbus_armada_set_timing_params(devbus, node, &r, &w);
309 }
310
311 /*
312 * We need to create a child device explicitly from here to
313 * guarantee that the child will be probed after the timing
314 * parameters for the bus are written.
315 */
316 err = of_platform_populate(node, NULL, NULL, dev);
317 if (err < 0)
318 return err;
319
320 return 0;
321}
322
323static const struct of_device_id mvebu_devbus_of_match[] = {
324 { .compatible = "marvell,mvebu-devbus" },
325 { .compatible = "marvell,orion-devbus" },
326 {},
327};
328MODULE_DEVICE_TABLE(of, mvebu_devbus_of_match);
329
330static struct platform_driver mvebu_devbus_driver = {
331 .probe = mvebu_devbus_probe,
332 .driver = {
333 .name = "mvebu-devbus",
334 .of_match_table = mvebu_devbus_of_match,
335 },
336};
337
338static int __init mvebu_devbus_init(void)
339{
340 return platform_driver_register(&mvebu_devbus_driver);
341}
342module_init(mvebu_devbus_init);
343
344MODULE_LICENSE("GPL v2");
345MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
346MODULE_DESCRIPTION("Marvell EBU SoC Device Bus controller");
1/*
2 * Marvell EBU SoC Device Bus Controller
3 * (memory controller for NOR/NAND/SRAM/FPGA devices)
4 *
5 * Copyright (C) 2013 Marvell
6 *
7 * This program is free software: you can 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 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 *
19 */
20
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/slab.h>
24#include <linux/err.h>
25#include <linux/io.h>
26#include <linux/clk.h>
27#include <linux/mbus.h>
28#include <linux/of_platform.h>
29#include <linux/of_address.h>
30#include <linux/platform_device.h>
31
32/* Register definitions */
33#define DEV_WIDTH_BIT 30
34#define BADR_SKEW_BIT 28
35#define RD_HOLD_BIT 23
36#define ACC_NEXT_BIT 17
37#define RD_SETUP_BIT 12
38#define ACC_FIRST_BIT 6
39
40#define SYNC_ENABLE_BIT 24
41#define WR_HIGH_BIT 16
42#define WR_LOW_BIT 8
43
44#define READ_PARAM_OFFSET 0x0
45#define WRITE_PARAM_OFFSET 0x4
46
47struct devbus_read_params {
48 u32 bus_width;
49 u32 badr_skew;
50 u32 turn_off;
51 u32 acc_first;
52 u32 acc_next;
53 u32 rd_setup;
54 u32 rd_hold;
55};
56
57struct devbus_write_params {
58 u32 sync_enable;
59 u32 wr_high;
60 u32 wr_low;
61 u32 ale_wr;
62};
63
64struct devbus {
65 struct device *dev;
66 void __iomem *base;
67 unsigned long tick_ps;
68};
69
70static int get_timing_param_ps(struct devbus *devbus,
71 struct device_node *node,
72 const char *name,
73 u32 *ticks)
74{
75 u32 time_ps;
76 int err;
77
78 err = of_property_read_u32(node, name, &time_ps);
79 if (err < 0) {
80 dev_err(devbus->dev, "%s has no '%s' property\n",
81 name, node->full_name);
82 return err;
83 }
84
85 *ticks = (time_ps + devbus->tick_ps - 1) / devbus->tick_ps;
86
87 dev_dbg(devbus->dev, "%s: %u ps -> 0x%x\n",
88 name, time_ps, *ticks);
89 return 0;
90}
91
92static int devbus_set_timing_params(struct devbus *devbus,
93 struct device_node *node)
94{
95 struct devbus_read_params r;
96 struct devbus_write_params w;
97 u32 value;
98 int err;
99
100 dev_dbg(devbus->dev, "Setting timing parameter, tick is %lu ps\n",
101 devbus->tick_ps);
102
103 /* Get read timings */
104 err = of_property_read_u32(node, "devbus,bus-width", &r.bus_width);
105 if (err < 0) {
106 dev_err(devbus->dev,
107 "%s has no 'devbus,bus-width' property\n",
108 node->full_name);
109 return err;
110 }
111
112 /*
113 * The bus width is encoded into the register as 0 for 8 bits,
114 * and 1 for 16 bits, so we do the necessary conversion here.
115 */
116 if (r.bus_width == 8)
117 r.bus_width = 0;
118 else if (r.bus_width == 16)
119 r.bus_width = 1;
120 else {
121 dev_err(devbus->dev, "invalid bus width %d\n", r.bus_width);
122 return -EINVAL;
123 }
124
125 err = get_timing_param_ps(devbus, node, "devbus,badr-skew-ps",
126 &r.badr_skew);
127 if (err < 0)
128 return err;
129
130 err = get_timing_param_ps(devbus, node, "devbus,turn-off-ps",
131 &r.turn_off);
132 if (err < 0)
133 return err;
134
135 err = get_timing_param_ps(devbus, node, "devbus,acc-first-ps",
136 &r.acc_first);
137 if (err < 0)
138 return err;
139
140 err = get_timing_param_ps(devbus, node, "devbus,acc-next-ps",
141 &r.acc_next);
142 if (err < 0)
143 return err;
144
145 err = get_timing_param_ps(devbus, node, "devbus,rd-setup-ps",
146 &r.rd_setup);
147 if (err < 0)
148 return err;
149
150 err = get_timing_param_ps(devbus, node, "devbus,rd-hold-ps",
151 &r.rd_hold);
152 if (err < 0)
153 return err;
154
155 /* Get write timings */
156 err = of_property_read_u32(node, "devbus,sync-enable",
157 &w.sync_enable);
158 if (err < 0) {
159 dev_err(devbus->dev,
160 "%s has no 'devbus,sync-enable' property\n",
161 node->full_name);
162 return err;
163 }
164
165 err = get_timing_param_ps(devbus, node, "devbus,ale-wr-ps",
166 &w.ale_wr);
167 if (err < 0)
168 return err;
169
170 err = get_timing_param_ps(devbus, node, "devbus,wr-low-ps",
171 &w.wr_low);
172 if (err < 0)
173 return err;
174
175 err = get_timing_param_ps(devbus, node, "devbus,wr-high-ps",
176 &w.wr_high);
177 if (err < 0)
178 return err;
179
180 /* Set read timings */
181 value = r.bus_width << DEV_WIDTH_BIT |
182 r.badr_skew << BADR_SKEW_BIT |
183 r.rd_hold << RD_HOLD_BIT |
184 r.acc_next << ACC_NEXT_BIT |
185 r.rd_setup << RD_SETUP_BIT |
186 r.acc_first << ACC_FIRST_BIT |
187 r.turn_off;
188
189 dev_dbg(devbus->dev, "read parameters register 0x%p = 0x%x\n",
190 devbus->base + READ_PARAM_OFFSET,
191 value);
192
193 writel(value, devbus->base + READ_PARAM_OFFSET);
194
195 /* Set write timings */
196 value = w.sync_enable << SYNC_ENABLE_BIT |
197 w.wr_low << WR_LOW_BIT |
198 w.wr_high << WR_HIGH_BIT |
199 w.ale_wr;
200
201 dev_dbg(devbus->dev, "write parameters register: 0x%p = 0x%x\n",
202 devbus->base + WRITE_PARAM_OFFSET,
203 value);
204
205 writel(value, devbus->base + WRITE_PARAM_OFFSET);
206
207 return 0;
208}
209
210static int mvebu_devbus_probe(struct platform_device *pdev)
211{
212 struct device *dev = &pdev->dev;
213 struct device_node *node = pdev->dev.of_node;
214 struct devbus *devbus;
215 struct resource *res;
216 struct clk *clk;
217 unsigned long rate;
218 int err;
219
220 devbus = devm_kzalloc(&pdev->dev, sizeof(struct devbus), GFP_KERNEL);
221 if (!devbus)
222 return -ENOMEM;
223
224 devbus->dev = dev;
225 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
226 devbus->base = devm_ioremap_resource(&pdev->dev, res);
227 if (IS_ERR(devbus->base))
228 return PTR_ERR(devbus->base);
229
230 clk = devm_clk_get(&pdev->dev, NULL);
231 if (IS_ERR(clk))
232 return PTR_ERR(clk);
233 clk_prepare_enable(clk);
234
235 /*
236 * Obtain clock period in picoseconds,
237 * we need this in order to convert timing
238 * parameters from cycles to picoseconds.
239 */
240 rate = clk_get_rate(clk) / 1000;
241 devbus->tick_ps = 1000000000 / rate;
242
243 /* Read the device tree node and set the new timing parameters */
244 err = devbus_set_timing_params(devbus, node);
245 if (err < 0)
246 return err;
247
248 /*
249 * We need to create a child device explicitly from here to
250 * guarantee that the child will be probed after the timing
251 * parameters for the bus are written.
252 */
253 err = of_platform_populate(node, NULL, NULL, dev);
254 if (err < 0)
255 return err;
256
257 return 0;
258}
259
260static const struct of_device_id mvebu_devbus_of_match[] = {
261 { .compatible = "marvell,mvebu-devbus" },
262 {},
263};
264MODULE_DEVICE_TABLE(of, mvebu_devbus_of_match);
265
266static struct platform_driver mvebu_devbus_driver = {
267 .probe = mvebu_devbus_probe,
268 .driver = {
269 .name = "mvebu-devbus",
270 .owner = THIS_MODULE,
271 .of_match_table = mvebu_devbus_of_match,
272 },
273};
274
275static int __init mvebu_devbus_init(void)
276{
277 return platform_driver_register(&mvebu_devbus_driver);
278}
279module_init(mvebu_devbus_init);
280
281MODULE_LICENSE("GPL v2");
282MODULE_AUTHOR("Ezequiel Garcia <ezequiel.garcia@free-electrons.com>");
283MODULE_DESCRIPTION("Marvell EBU SoC Device Bus controller");