OpenWrt – Blame information for rev 4

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4 office 1 From be64c4dbf6be17ce20ee214478509a3738256d46 Mon Sep 17 00:00:00 2001
2 From: Luke Wren <wren6991@gmail.com>
3 Date: Sat, 5 Sep 2015 01:16:10 +0100
4 Subject: [PATCH] Add SMI NAND driver
5  
6 Signed-off-by: Luke Wren <wren6991@gmail.com>
7 ---
8 .../bindings/mtd/brcm,bcm2835-smi-nand.txt | 42 ++++
9 drivers/mtd/nand/Kconfig | 7 +
10 drivers/mtd/nand/Makefile | 1 +
11 drivers/mtd/nand/bcm2835_smi_nand.c | 267 +++++++++++++++++++++
12 4 files changed, 317 insertions(+)
13 create mode 100644 Documentation/devicetree/bindings/mtd/brcm,bcm2835-smi-nand.txt
14 create mode 100644 drivers/mtd/nand/bcm2835_smi_nand.c
15  
16 --- /dev/null
17 +++ b/Documentation/devicetree/bindings/mtd/brcm,bcm2835-smi-nand.txt
18 @@ -0,0 +1,42 @@
19 +* BCM2835 SMI NAND flash
20 +
21 +This driver is a shim between the BCM2835 SMI driver (SMI is a peripheral for
22 +talking to parallel register interfaces) and Linux's MTD layer.
23 +
24 +Required properties:
25 +- compatible: "brcm,bcm2835-smi-nand"
26 +- status: "okay"
27 +
28 +Optional properties:
29 +- partition@n, where n is an integer from a consecutive sequence starting at 0
30 + - Difficult to store partition table on NAND device - normally put it
31 + in the source code, kernel bootparams, or device tree (the best way!)
32 + - Sub-properties:
33 + - label: the partition name, as shown by mtdinfo /dev/mtd*
34 + - reg: the size and offset of this partition.
35 + - (optional) read-only: an empty property flagging as read only
36 +
37 +Example:
38 +
39 +nand: flash@0 {
40 + compatible = "brcm,bcm2835-smi-nand";
41 + status = "okay";
42 +
43 + partition@0 {
44 + label = "stage2";
45 + // 128k
46 + reg = <0 0x20000>;
47 + read-only;
48 + };
49 + partition@1 {
50 + label = "firmware";
51 + // 16M
52 + reg = <0x20000 0x1000000>;
53 + read-only;
54 + };
55 + partition@2 {
56 + label = "root";
57 + // 2G
58 + reg = <0x1020000 0x80000000>;
59 + };
60 +};
61 \ No newline at end of file
62 --- a/drivers/mtd/nand/Kconfig
63 +++ b/drivers/mtd/nand/Kconfig
64 @@ -41,6 +41,13 @@ config MTD_SM_COMMON
65 tristate
66 default n
67  
68 +config MTD_NAND_BCM2835_SMI
69 + tristate "Use Broadcom's Secondary Memory Interface as a NAND controller (BCM283x)"
70 + depends on BCM2835_SMI
71 + default m
72 + help
73 + Uses the BCM2835's SMI peripheral as a NAND controller.
74 +
75 config MTD_NAND_DENALI
76 tristate
77  
78 --- a/drivers/mtd/nand/Makefile
79 +++ b/drivers/mtd/nand/Makefile
80 @@ -14,6 +14,7 @@ obj-$(CONFIG_MTD_NAND_DENALI) += denali
81 obj-$(CONFIG_MTD_NAND_DENALI_PCI) += denali_pci.o
82 obj-$(CONFIG_MTD_NAND_DENALI_DT) += denali_dt.o
83 obj-$(CONFIG_MTD_NAND_AU1550) += au1550nd.o
84 +obj-$(CONFIG_MTD_NAND_BCM2835_SMI) += bcm2835_smi_nand.o
85 obj-$(CONFIG_MTD_NAND_BF5XX) += bf5xx_nand.o
86 obj-$(CONFIG_MTD_NAND_S3C2410) += s3c2410.o
87 obj-$(CONFIG_MTD_NAND_DAVINCI) += davinci_nand.o
88 --- /dev/null
89 +++ b/drivers/mtd/nand/bcm2835_smi_nand.c
90 @@ -0,0 +1,267 @@
91 +/**
92 + * NAND flash driver for Broadcom Secondary Memory Interface
93 + *
94 + * Written by Luke Wren <luke@raspberrypi.org>
95 + * Copyright (c) 2015, Raspberry Pi (Trading) Ltd.
96 + *
97 + * Redistribution and use in source and binary forms, with or without
98 + * modification, are permitted provided that the following conditions
99 + * are met:
100 + * 1. Redistributions of source code must retain the above copyright
101 + * notice, this list of conditions, and the following disclaimer,
102 + * without modification.
103 + * 2. Redistributions in binary form must reproduce the above copyright
104 + * notice, this list of conditions and the following disclaimer in the
105 + * documentation and/or other materials provided with the distribution.
106 + * 3. The names of the above-listed copyright holders may not be used
107 + * to endorse or promote products derived from this software without
108 + * specific prior written permission.
109 + *
110 + * ALTERNATIVELY, this software may be distributed under the terms of the
111 + * GNU General Public License ("GPL") version 2, as published by the Free
112 + * Software Foundation.
113 + *
114 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
115 + * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
116 + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
117 + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
118 + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
119 + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
120 + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
121 + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
122 + * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
123 + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
124 + * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
125 + */
126 +
127 +#include <linux/kernel.h>
128 +#include <linux/module.h>
129 +#include <linux/of.h>
130 +#include <linux/platform_device.h>
131 +#include <linux/slab.h>
132 +#include <linux/mtd/nand.h>
133 +#include <linux/mtd/partitions.h>
134 +
135 +#include <linux/broadcom/bcm2835_smi.h>
136 +
137 +#define DEVICE_NAME "bcm2835-smi-nand"
138 +#define DRIVER_NAME "smi-nand-bcm2835"
139 +
140 +struct bcm2835_smi_nand_host {
141 + struct bcm2835_smi_instance *smi_inst;
142 + struct nand_chip nand_chip;
143 + struct mtd_info mtd;
144 + struct device *dev;
145 +};
146 +
147 +/****************************************************************************
148 +*
149 +* NAND functionality implementation
150 +*
151 +****************************************************************************/
152 +
153 +#define SMI_NAND_CLE_PIN 0x01
154 +#define SMI_NAND_ALE_PIN 0x02
155 +
156 +static inline void bcm2835_smi_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
157 + unsigned int ctrl)
158 +{
159 + uint32_t cmd32 = cmd;
160 + uint32_t addr = ~(SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
161 + struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
162 + struct bcm2835_smi_instance *inst = host->smi_inst;
163 +
164 + if (ctrl & NAND_CLE)
165 + addr |= SMI_NAND_CLE_PIN;
166 + if (ctrl & NAND_ALE)
167 + addr |= SMI_NAND_ALE_PIN;
168 + /* Lower ALL the CS pins! */
169 + if (ctrl & NAND_NCE)
170 + addr &= (SMI_NAND_CLE_PIN | SMI_NAND_ALE_PIN);
171 +
172 + bcm2835_smi_set_address(inst, addr);
173 +
174 + if (cmd != NAND_CMD_NONE)
175 + bcm2835_smi_write_buf(inst, &cmd32, 1);
176 +}
177 +
178 +static inline uint8_t bcm2835_smi_nand_read_byte(struct mtd_info *mtd)
179 +{
180 + uint8_t byte;
181 + struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
182 + struct bcm2835_smi_instance *inst = host->smi_inst;
183 +
184 + bcm2835_smi_read_buf(inst, &byte, 1);
185 + return byte;
186 +}
187 +
188 +static inline void bcm2835_smi_nand_write_byte(struct mtd_info *mtd,
189 + uint8_t byte)
190 +{
191 + struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
192 + struct bcm2835_smi_instance *inst = host->smi_inst;
193 +
194 + bcm2835_smi_write_buf(inst, &byte, 1);
195 +}
196 +
197 +static inline void bcm2835_smi_nand_write_buf(struct mtd_info *mtd,
198 + const uint8_t *buf, int len)
199 +{
200 + struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
201 + struct bcm2835_smi_instance *inst = host->smi_inst;
202 +
203 + bcm2835_smi_write_buf(inst, buf, len);
204 +}
205 +
206 +static inline void bcm2835_smi_nand_read_buf(struct mtd_info *mtd,
207 + uint8_t *buf, int len)
208 +{
209 + struct bcm2835_smi_nand_host *host = dev_get_drvdata(mtd->dev.parent);
210 + struct bcm2835_smi_instance *inst = host->smi_inst;
211 +
212 + bcm2835_smi_read_buf(inst, buf, len);
213 +}
214 +
215 +/****************************************************************************
216 +*
217 +* Probe and remove functions
218 +*
219 +***************************************************************************/
220 +
221 +static int bcm2835_smi_nand_probe(struct platform_device *pdev)
222 +{
223 + struct bcm2835_smi_nand_host *host;
224 + struct nand_chip *this;
225 + struct mtd_info *mtd;
226 + struct device *dev = &pdev->dev;
227 + struct device_node *node = dev->of_node, *smi_node;
228 + struct mtd_part_parser_data ppdata;
229 + struct smi_settings *smi_settings;
230 + struct bcm2835_smi_instance *smi_inst;
231 + int ret = -ENXIO;
232 +
233 + if (!node) {
234 + dev_err(dev, "No device tree node supplied!");
235 + return -EINVAL;
236 + }
237 +
238 + smi_node = of_parse_phandle(node, "smi_handle", 0);
239 +
240 + /* Request use of SMI peripheral: */
241 + smi_inst = bcm2835_smi_get(smi_node);
242 +
243 + if (!smi_inst) {
244 + dev_err(dev, "Could not register with SMI.");
245 + return -EPROBE_DEFER;
246 + }
247 +
248 + /* Set SMI timing and bus width */
249 +
250 + smi_settings = bcm2835_smi_get_settings_from_regs(smi_inst);
251 +
252 + smi_settings->data_width = SMI_WIDTH_8BIT;
253 + smi_settings->read_setup_time = 2;
254 + smi_settings->read_hold_time = 1;
255 + smi_settings->read_pace_time = 1;
256 + smi_settings->read_strobe_time = 3;
257 +
258 + smi_settings->write_setup_time = 2;
259 + smi_settings->write_hold_time = 1;
260 + smi_settings->write_pace_time = 1;
261 + smi_settings->write_strobe_time = 3;
262 +
263 + bcm2835_smi_set_regs_from_settings(smi_inst);
264 +
265 + host = devm_kzalloc(dev, sizeof(struct bcm2835_smi_nand_host),
266 + GFP_KERNEL);
267 + if (!host)
268 + return -ENOMEM;
269 +
270 + host->dev = dev;
271 + host->smi_inst = smi_inst;
272 +
273 + platform_set_drvdata(pdev, host);
274 +
275 + /* Link the structures together */
276 +
277 + this = &host->nand_chip;
278 + mtd = &host->mtd;
279 + mtd->priv = this;
280 + mtd->owner = THIS_MODULE;
281 + mtd->dev.parent = dev;
282 + mtd->name = DRIVER_NAME;
283 +
284 + /* 20 us command delay time... */
285 + this->chip_delay = 20;
286 +
287 + this->priv = host;
288 + this->cmd_ctrl = bcm2835_smi_nand_cmd_ctrl;
289 + this->read_byte = bcm2835_smi_nand_read_byte;
290 + this->write_byte = bcm2835_smi_nand_write_byte;
291 + this->write_buf = bcm2835_smi_nand_write_buf;
292 + this->read_buf = bcm2835_smi_nand_read_buf;
293 +
294 + this->ecc.mode = NAND_ECC_SOFT;
295 +
296 + /* Should never be accessed directly: */
297 +
298 + this->IO_ADDR_R = (void *)0xdeadbeef;
299 + this->IO_ADDR_W = (void *)0xdeadbeef;
300 +
301 + /* First scan to find the device and get the page size */
302 +
303 + if (nand_scan_ident(mtd, 1, NULL))
304 + return -ENXIO;
305 +
306 + /* Second phase scan */
307 +
308 + if (nand_scan_tail(mtd))
309 + return -ENXIO;
310 +
311 + ret = mtd_device_parse_register(mtd, NULL, &ppdata, NULL, 0);
312 + if (!ret)
313 + return 0;
314 +
315 + nand_release(mtd);
316 + return -EINVAL;
317 +}
318 +
319 +static int bcm2835_smi_nand_remove(struct platform_device *pdev)
320 +{
321 + struct bcm2835_smi_nand_host *host = platform_get_drvdata(pdev);
322 +
323 + nand_release(&host->mtd);
324 +
325 + return 0;
326 +}
327 +
328 +/****************************************************************************
329 +*
330 +* Register the driver with device tree
331 +*
332 +***************************************************************************/
333 +
334 +static const struct of_device_id bcm2835_smi_nand_of_match[] = {
335 + {.compatible = "brcm,bcm2835-smi-nand",},
336 + { /* sentinel */ }
337 +};
338 +
339 +MODULE_DEVICE_TABLE(of, bcm2835_smi_nand_of_match);
340 +
341 +static struct platform_driver bcm2835_smi_nand_driver = {
342 + .probe = bcm2835_smi_nand_probe,
343 + .remove = bcm2835_smi_nand_remove,
344 + .driver = {
345 + .name = DRIVER_NAME,
346 + .owner = THIS_MODULE,
347 + .of_match_table = bcm2835_smi_nand_of_match,
348 + },
349 +};
350 +
351 +module_platform_driver(bcm2835_smi_nand_driver);
352 +
353 +MODULE_ALIAS("platform:smi-nand-bcm2835");
354 +MODULE_LICENSE("GPL");
355 +MODULE_DESCRIPTION
356 + ("Driver for NAND chips using Broadcom Secondary Memory Interface");
357 +MODULE_AUTHOR("Luke Wren <luke@raspberrypi.org>");