summaryrefslogtreecommitdiff
path: root/target/linux/brcm2708/patches-4.4/0042-Add-SMI-NAND-driver.patch
blob: 2807310a4a02677343bf111ded5516d64fe2d98b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
From 06301e219cb176ca2917ad7e51fc9cf9897cf52b Mon Sep 17 00:00:00 2001
From: Luke Wren <wren6991@gmail.com>
Date: Sat, 5 Sep 2015 01:16:10 +0100
Subject: [PATCH 042/156] Add SMI NAND driver

Signed-off-by: Luke Wren <wren6991@gmail.com>
---
 .../bindings/mtd/brcm,bcm2835-smi-nand.txt         |  42 ++++
 drivers/mtd/nand/Kconfig                           |   7 +
 drivers/mtd/nand/Makefile                          |   1 +
 drivers/mtd/nand/bcm2835_smi_nand.c                | 268 +++++++++++++++++++++
 4 files changed, 318 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mtd/brcm,bcm2835-smi-nand.txt
 create mode 100644 drivers/mtd/nand/bcm2835_smi_nand.c

--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/brcm,bcm2835-smi-nand.txt
@@ -0,0 +1,42 @@
+* BCM2835 SMI NAND flash
+
+This driver is a shim between the BCM2835 SMI driver (SMI is a peripheral for
+talking to parallel register interfaces) and Linux's MTD layer.
+
+Required properties:
+- compatible: "brcm,bcm2835-smi-nand"
+- status: "okay"
+
+Optional properties:
+- partition@n, where n is an integer from a consecutive sequence starting at 0
+	- Difficult to store partition table on NAND device - normally put it
+	in the source code, kernel bootparams, or device tree (the best way!)
+	- Sub-properties:
+		- label: the partition name, as shown by mtdinfo /dev/mtd*
+		- reg: the size and offset of this partition.
+		- (optional) read-only: an empty property flagging as read only
+
+Example:
+
+nand: flash@0 {
+	compatible = "brcm,bcm2835-smi-nand";
+	status = "okay";
+
+	partition@0 {
+		label = "stage2";
+		// 128k
+		reg = <0 0x20000>;
+		read-only;
+	};
+	partition@1 {
+		label = "firmware";
+		// 16M
+		reg = <0x20000 0x1000000>;
+		read-only;
+	};
+	partition@2 {
+		label = "root";
+		// 2G
+		reg = <0x1020000 0x80000000>;
+	};
+};
\ No newline at end of file
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -41,6 +41,13 @@ config MTD_SM_COMMON
 	tristate
 	default n
 
+config MTD_NAND_BCM2835_SMI
+        tristate "Use Broadcom's Secondary Memory Interface as a NAND controller (BCM283x)"
+        depends on (MACH_BCM2708 || MACH_BCM2709 || ARCH_BCM2835) && BCM2835_SMI && MTD_NAND
+        default m
+        help
+	  Uses the BCM2835's SMI peripheral as a NAND controller.
+
 config MTD_NAND_DENALI
 	tristate
 
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_MTD_NAND_DENALI)		+= denali
 obj-$(CONFIG_MTD_NAND_DENALI_PCI)	+= denali_pci.o
 obj-$(CONFIG_MTD_NAND_DENALI_DT)	+= denali_dt.o
 obj-$(CONFIG_MTD_NAND_AU1550)		+= au1550nd.o
+obj-$(CONFIG_MTD_NAND_BCM2835_SMI)	+= bcm2835_smi_nand.o
 obj-$(CONFIG_MTD_NAND_BF5XX)		+= bf5xx_nand.o
 obj-$(CONFIG_MTD_NAND_S3C2410)		+= s3c2410.o
 obj-$(CONFIG_MTD_NAND_DAVINCI)		+= davinci_nand.o
--- /dev/null
+++ b/drivers/mtd/nand/bcm2835_smi_nand.c
@@ -0,0 +1,268 @@
+/**
+ * NAND flash driver for Broadcom Secondary Memory Interface
+ *
+ * Written by Luke Wren <luke@raspberrypi.org>
+ * Copyright (c) 2015, Raspberry Pi (Trading) Ltd.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2, as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/partitions.h>
+
+#include <linux/broadcom/bcm2835_smi.h>
+
+#define DEVICE_NAME "bcm2835-smi-nand"
+#define DRIVER_NAME "smi-nand-bcm2835"
+
+struct bcm2835_smi_nand_host {
+	struct bcm2835_smi_instance *smi_inst;
+	struct nand_chip nand_chip;
+	struct mtd_info mtd;
+	struct device *dev;
+};
+
+/****************************************************************************
+*
+*   NAND functionality implementation
+*
+****************************************************************************/
+
+#define SMI_NAND_CLE_PIN 0x01
+#define SMI_NAND_ALE_PIN 0x02
+
+static inline void bcm2835_smi_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
+					     unsigned int ctrl)
+{
+	uint32_t cmd32 = cmd;
+	uint32_t addr = ~(SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
+	struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+	struct bcm2835_smi_instance *inst = host->smi_inst;
+
+	if (ctrl & NAND_CLE)
+		addr |= SMI_NAND_CLE_PIN;
+	if (ctrl & NAND_ALE)
+		addr |= SMI_NAND_ALE_PIN;
+	/* Lower ALL the CS pins! */
+	if (ctrl & NAND_NCE)
+		addr &= (SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
+
+	bcm2835_smi_set_address(inst, addr);
+
+	if (cmd != NAND_CMD_NONE)
+		bcm2835_smi_write_buf(inst, &cmd32, 1);
+}
+
+static inline uint8_t bcm2835_smi_nand_read_byte(struct mtd_info *mtd)
+{
+	uint8_t byte;
+	struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+	struct bcm2835_smi_instance *inst = host->smi_inst;
+
+	bcm2835_smi_read_buf(inst, &byte, 1);
+	return byte;
+}
+
+static inline void bcm2835_smi_nand_write_byte(struct mtd_info *mtd,
+					       uint8_t byte)
+{
+	struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+	struct bcm2835_smi_instance *inst = host->smi_inst;
+
+	bcm2835_smi_write_buf(inst, &byte, 1);
+}
+
+static inline void bcm2835_smi_nand_write_buf(struct mtd_info *mtd,
+					      const uint8_t *buf, int len)
+{
+	struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+	struct bcm2835_smi_instance *inst = host->smi_inst;
+
+	bcm2835_smi_write_buf(inst, buf, len);
+}
+
+static inline void bcm2835_smi_nand_read_buf(struct mtd_info *mtd,
+					     uint8_t *buf, int len)
+{
+	struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
+	struct bcm2835_smi_instance *inst = host->smi_inst;
+
+	bcm2835_smi_read_buf(inst, buf, len);
+}
+
+/****************************************************************************
+*
+*   Probe and remove functions
+*
+***************************************************************************/
+
+static int bcm2835_smi_nand_probe(struct platform_device *pdev)
+{
+	struct bcm2835_smi_nand_host *host;
+	struct nand_chip *this;
+	struct mtd_info *mtd;
+	struct device *dev = &pdev->dev;
+	struct device_node *node = dev->of_node, *smi_node;
+	struct mtd_part_parser_data ppdata;
+	struct smi_settings *smi_settings;
+	struct bcm2835_smi_instance *smi_inst;
+	int ret = -ENXIO;
+
+	if (!node) {
+		dev_err(dev, "No device tree node supplied!");
+		return -EINVAL;
+	}
+
+	smi_node = of_parse_phandle(node, "smi_handle", 0);
+
+	/* Request use of SMI peripheral: */
+	smi_inst = bcm2835_smi_get(smi_node);
+
+	if (!smi_inst) {
+		dev_err(dev, "Could not register with SMI.");
+		return -EPROBE_DEFER;
+	}
+
+	/* Set SMI timing and bus width */
+
+	smi_settings = bcm2835_smi_get_settings_from_regs(smi_inst);
+
+	smi_settings->data_width = SMI_WIDTH_8BIT;
+	smi_settings->read_setup_time = 2;
+	smi_settings->read_hold_time = 1;
+	smi_settings->read_pace_time = 1;
+	smi_settings->read_strobe_time = 3;
+
+	smi_settings->write_setup_time = 2;
+	smi_settings->write_hold_time = 1;
+	smi_settings->write_pace_time = 1;
+	smi_settings->write_strobe_time = 3;
+
+	bcm2835_smi_set_regs_from_settings(smi_inst);
+
+	host = devm_kzalloc(dev, sizeof(struct bcm2835_smi_nand_host),
+		GFP_KERNEL);
+	if (!host)
+		return -ENOMEM;
+
+	host->dev = dev;
+	host->smi_inst = smi_inst;
+
+	platform_set_drvdata(pdev, host);
+
+	/* Link the structures together */
+
+	this = &host->nand_chip;
+	mtd = &host->mtd;
+	mtd->priv = this;
+	mtd->owner = THIS_MODULE;
+	mtd->dev.parent = dev;
+	mtd->name = DRIVER_NAME;
+	ppdata.of_node = node;
+
+	/* 20 us command delay time... */
+	this->chip_delay = 20;
+
+	this->priv = host;
+	this->cmd_ctrl = bcm2835_smi_nand_cmd_ctrl;
+	this->read_byte = bcm2835_smi_nand_read_byte;
+	this->write_byte = bcm2835_smi_nand_write_byte;
+	this->write_buf = bcm2835_smi_nand_write_buf;
+	this->read_buf = bcm2835_smi_nand_read_buf;
+
+	this->ecc.mode = NAND_ECC_SOFT;
+
+	/* Should never be accessed directly: */
+
+	this->IO_ADDR_R = (void *)0xdeadbeef;
+	this->IO_ADDR_W = (void *)0xdeadbeef;
+
+	/* First scan to find the device and get the page size */
+
+	if (nand_scan_ident(mtd, 1, NULL))
+		return -ENXIO;
+
+	/* Second phase scan */
+
+	if (nand_scan_tail(mtd))
+		return -ENXIO;
+
+	ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
+	if (!ret)
+		return 0;
+
+	nand_release(mtd);
+	return -EINVAL;
+}
+
+static int bcm2835_smi_nand_remove(struct platform_device *pdev)
+{
+	struct bcm2835_smi_nand_host *host = platform_get_drvdata(pdev);
+
+	nand_release(&host->mtd);
+
+	return 0;
+}
+
+/****************************************************************************
+*
+*   Register the driver with device tree
+*
+***************************************************************************/
+
+static const struct of_device_id bcm2835_smi_nand_of_match[] = {
+	{.compatible = "brcm,bcm2835-smi-nand",},
+	{ /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, bcm2835_smi_nand_of_match);
+
+static struct platform_driver bcm2835_smi_nand_driver = {
+	.probe = bcm2835_smi_nand_probe,
+	.remove = bcm2835_smi_nand_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+		.of_match_table = bcm2835_smi_nand_of_match,
+	},
+};
+
+module_platform_driver(bcm2835_smi_nand_driver);
+
+MODULE_ALIAS("platform:smi-nand-bcm2835");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION
+	("Driver for NAND chips using Broadcom Secondary Memory Interface");
+MODULE_AUTHOR("Luke Wren <luke@raspberrypi.org>");