1/*
2 * EIM driver for Freescale's i.MX chips
3 *
4 * Copyright (C) 2013 Freescale Semiconductor, Inc.
5 *
6 * This file is licensed under the terms of the GNU General Public
7 * License version 2. This program is licensed "as is" without any
8 * warranty of any kind, whether express or implied.
9 */
10#include <linux/module.h>
11#include <linux/clk.h>
12#include <linux/io.h>
13#include <linux/of_address.h>
14#include <linux/of.h>
15#include <linux/of_platform.h>
16#include <linux/platform_device.h>
17#include <linux/property.h>
18#include <linux/mfd/syscon.h>
19#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
20#include <linux/regmap.h>
21
22struct imx_weim_devtype {
23 unsigned int cs_count;
24 unsigned int cs_regs_count;
25 unsigned int cs_stride;
26 unsigned int wcr_offset;
27 unsigned int wcr_bcm;
28 unsigned int wcr_cont_bclk;
29};
30
31static const struct imx_weim_devtype imx1_weim_devtype = {
32 .cs_count = 6,
33 .cs_regs_count = 2,
34 .cs_stride = 0x08,
35};
36
37static const struct imx_weim_devtype imx27_weim_devtype = {
38 .cs_count = 6,
39 .cs_regs_count = 3,
40 .cs_stride = 0x10,
41};
42
43static const struct imx_weim_devtype imx50_weim_devtype = {
44 .cs_count = 4,
45 .cs_regs_count = 6,
46 .cs_stride = 0x18,
47 .wcr_offset = 0x90,
48 .wcr_bcm = BIT(0),
49 .wcr_cont_bclk = BIT(3),
50};
51
52static const struct imx_weim_devtype imx51_weim_devtype = {
53 .cs_count = 6,
54 .cs_regs_count = 6,
55 .cs_stride = 0x18,
56};
57
58#define MAX_CS_REGS_COUNT 6
59#define MAX_CS_COUNT 6
60#define OF_REG_SIZE 3
61
62struct cs_timing {
63 bool is_applied;
64 u32 regs[MAX_CS_REGS_COUNT];
65};
66
67struct cs_timing_state {
68 struct cs_timing cs[MAX_CS_COUNT];
69};
70
71struct weim_priv {
72 void __iomem *base;
73 struct cs_timing_state timing_state;
74};
75
76static const struct of_device_id weim_id_table[] = {
77 /* i.MX1/21 */
78 { .compatible = "fsl,imx1-weim", .data = &imx1_weim_devtype, },
79 /* i.MX25/27/31/35 */
80 { .compatible = "fsl,imx27-weim", .data = &imx27_weim_devtype, },
81 /* i.MX50/53/6Q */
82 { .compatible = "fsl,imx50-weim", .data = &imx50_weim_devtype, },
83 { .compatible = "fsl,imx6q-weim", .data = &imx50_weim_devtype, },
84 /* i.MX51 */
85 { .compatible = "fsl,imx51-weim", .data = &imx51_weim_devtype, },
86 { }
87};
88MODULE_DEVICE_TABLE(of, weim_id_table);
89
90static int imx_weim_gpr_setup(struct platform_device *pdev)
91{
92 struct device_node *np = pdev->dev.of_node;
93 struct of_range_parser parser;
94 struct of_range range;
95 struct regmap *gpr;
96 u32 gprvals[4] = {
97 05, /* CS0(128M) CS1(0M) CS2(0M) CS3(0M) */
98 033, /* CS0(64M) CS1(64M) CS2(0M) CS3(0M) */
99 0113, /* CS0(64M) CS1(32M) CS2(32M) CS3(0M) */
100 01111, /* CS0(32M) CS1(32M) CS2(32M) CS3(32M) */
101 };
102 u32 gprval = 0;
103 u32 val;
104 int cs = 0;
105 int i = 0;
106
107 gpr = syscon_regmap_lookup_by_phandle(np, property: "fsl,weim-cs-gpr");
108 if (IS_ERR(ptr: gpr)) {
109 dev_dbg(&pdev->dev, "failed to find weim-cs-gpr\n");
110 return 0;
111 }
112
113 if (of_range_parser_init(parser: &parser, node: np))
114 goto err;
115
116 for_each_of_range(&parser, &range) {
117 cs = range.bus_addr >> 32;
118 val = (range.size / SZ_32M) | 1;
119 gprval |= val << cs * 3;
120 i++;
121 }
122
123 if (i == 0)
124 goto err;
125
126 for (i = 0; i < ARRAY_SIZE(gprvals); i++) {
127 if (gprval == gprvals[i]) {
128 /* Found it. Set up IOMUXC_GPR1[11:0] with it. */
129 regmap_update_bits(map: gpr, IOMUXC_GPR1, mask: 0xfff, val: gprval);
130 return 0;
131 }
132 }
133
134err:
135 dev_err(&pdev->dev, "Invalid 'ranges' configuration\n");
136 return -EINVAL;
137}
138
139/* Parse and set the timing for this device. */
140static int weim_timing_setup(struct device *dev, struct device_node *np,
141 const struct imx_weim_devtype *devtype)
142{
143 u32 cs_idx, value[MAX_CS_REGS_COUNT];
144 int i, ret;
145 int reg_idx, num_regs;
146 struct cs_timing *cst;
147 struct weim_priv *priv;
148 struct cs_timing_state *ts;
149 void __iomem *base;
150
151 if (WARN_ON(devtype->cs_regs_count > MAX_CS_REGS_COUNT))
152 return -EINVAL;
153 if (WARN_ON(devtype->cs_count > MAX_CS_COUNT))
154 return -EINVAL;
155
156 priv = dev_get_drvdata(dev);
157 base = priv->base;
158 ts = &priv->timing_state;
159
160 ret = of_property_read_u32_array(np, propname: "fsl,weim-cs-timing",
161 out_values: value, sz: devtype->cs_regs_count);
162 if (ret)
163 return ret;
164
165 /*
166 * the child node's "reg" property may contain multiple address ranges,
167 * extract the chip select for each.
168 */
169 num_regs = of_property_count_elems_of_size(np, propname: "reg", OF_REG_SIZE);
170 if (num_regs < 0)
171 return num_regs;
172 if (!num_regs)
173 return -EINVAL;
174 for (reg_idx = 0; reg_idx < num_regs; reg_idx++) {
175 /* get the CS index from this child node's "reg" property. */
176 ret = of_property_read_u32_index(np, propname: "reg",
177 index: reg_idx * OF_REG_SIZE, out_value: &cs_idx);
178 if (ret)
179 break;
180
181 if (cs_idx >= devtype->cs_count)
182 return -EINVAL;
183
184 /* prevent re-configuring a CS that's already been configured */
185 cst = &ts->cs[cs_idx];
186 if (cst->is_applied && memcmp(p: value, q: cst->regs,
187 size: devtype->cs_regs_count * sizeof(u32))) {
188 dev_err(dev, "fsl,weim-cs-timing conflict on %pOF", np);
189 return -EINVAL;
190 }
191
192 /* set the timing for WEIM */
193 for (i = 0; i < devtype->cs_regs_count; i++)
194 writel(val: value[i],
195 addr: base + cs_idx * devtype->cs_stride + i * 4);
196 if (!cst->is_applied) {
197 cst->is_applied = true;
198 memcpy(cst->regs, value,
199 devtype->cs_regs_count * sizeof(u32));
200 }
201 }
202
203 return 0;
204}
205
206static int weim_parse_dt(struct platform_device *pdev)
207{
208 const struct imx_weim_devtype *devtype = device_get_match_data(dev: &pdev->dev);
209 int ret = 0, have_child = 0;
210 struct device_node *child;
211 struct weim_priv *priv;
212 void __iomem *base;
213 u32 reg;
214
215 if (devtype == &imx50_weim_devtype) {
216 ret = imx_weim_gpr_setup(pdev);
217 if (ret)
218 return ret;
219 }
220
221 priv = dev_get_drvdata(dev: &pdev->dev);
222 base = priv->base;
223
224 if (of_property_read_bool(np: pdev->dev.of_node, propname: "fsl,burst-clk-enable")) {
225 if (devtype->wcr_bcm) {
226 reg = readl(addr: base + devtype->wcr_offset);
227 reg |= devtype->wcr_bcm;
228
229 if (of_property_read_bool(np: pdev->dev.of_node,
230 propname: "fsl,continuous-burst-clk")) {
231 if (devtype->wcr_cont_bclk) {
232 reg |= devtype->wcr_cont_bclk;
233 } else {
234 dev_err(&pdev->dev,
235 "continuous burst clk not supported.\n");
236 return -EINVAL;
237 }
238 }
239
240 writel(val: reg, addr: base + devtype->wcr_offset);
241 } else {
242 dev_err(&pdev->dev, "burst clk mode not supported.\n");
243 return -EINVAL;
244 }
245 }
246
247 for_each_available_child_of_node(pdev->dev.of_node, child) {
248 ret = weim_timing_setup(dev: &pdev->dev, np: child, devtype);
249 if (ret)
250 dev_warn(&pdev->dev, "%pOF set timing failed.\n",
251 child);
252 else
253 have_child = 1;
254 }
255
256 if (have_child)
257 ret = of_platform_default_populate(root: pdev->dev.of_node,
258 NULL, parent: &pdev->dev);
259 if (ret)
260 dev_err(&pdev->dev, "%pOF fail to create devices.\n",
261 pdev->dev.of_node);
262 return ret;
263}
264
265static int weim_probe(struct platform_device *pdev)
266{
267 struct weim_priv *priv;
268 struct clk *clk;
269 void __iomem *base;
270 int ret;
271
272 priv = devm_kzalloc(dev: &pdev->dev, size: sizeof(*priv), GFP_KERNEL);
273 if (!priv)
274 return -ENOMEM;
275
276 /* get the resource */
277 base = devm_platform_ioremap_resource(pdev, index: 0);
278 if (IS_ERR(ptr: base))
279 return PTR_ERR(ptr: base);
280
281 priv->base = base;
282 dev_set_drvdata(dev: &pdev->dev, data: priv);
283
284 /* get the clock */
285 clk = devm_clk_get_enabled(dev: &pdev->dev, NULL);
286 if (IS_ERR(ptr: clk))
287 return PTR_ERR(ptr: clk);
288
289 /* parse the device node */
290 ret = weim_parse_dt(pdev);
291 if (ret)
292 return ret;
293
294 dev_info(&pdev->dev, "Driver registered.\n");
295
296 return 0;
297}
298
299#if IS_ENABLED(CONFIG_OF_DYNAMIC)
300static int of_weim_notify(struct notifier_block *nb, unsigned long action,
301 void *arg)
302{
303 const struct imx_weim_devtype *devtype;
304 struct of_reconfig_data *rd = arg;
305 const struct of_device_id *of_id;
306 struct platform_device *pdev;
307 int ret = NOTIFY_OK;
308
309 switch (of_reconfig_get_state_change(action, arg: rd)) {
310 case OF_RECONFIG_CHANGE_ADD:
311 of_id = of_match_node(matches: weim_id_table, node: rd->dn->parent);
312 if (!of_id)
313 return NOTIFY_OK; /* not for us */
314
315 devtype = of_id->data;
316
317 pdev = of_find_device_by_node(np: rd->dn->parent);
318 if (!pdev) {
319 pr_err("%s: could not find platform device for '%pOF'\n",
320 __func__, rd->dn->parent);
321
322 return notifier_from_errno(err: -EINVAL);
323 }
324
325 if (weim_timing_setup(dev: &pdev->dev, np: rd->dn, devtype))
326 dev_warn(&pdev->dev,
327 "Failed to setup timing for '%pOF'\n", rd->dn);
328
329 if (!of_node_check_flag(n: rd->dn, OF_POPULATED)) {
330 /*
331 * Clear the flag before adding the device so that
332 * fw_devlink doesn't skip adding consumers to this
333 * device.
334 */
335 rd->dn->fwnode.flags &= ~FWNODE_FLAG_NOT_DEVICE;
336 if (!of_platform_device_create(np: rd->dn, NULL, parent: &pdev->dev)) {
337 dev_err(&pdev->dev,
338 "Failed to create child device '%pOF'\n",
339 rd->dn);
340 ret = notifier_from_errno(err: -EINVAL);
341 }
342 }
343
344 platform_device_put(pdev);
345
346 break;
347 case OF_RECONFIG_CHANGE_REMOVE:
348 if (!of_node_check_flag(n: rd->dn, OF_POPULATED))
349 return NOTIFY_OK; /* device already destroyed */
350
351 of_id = of_match_node(matches: weim_id_table, node: rd->dn->parent);
352 if (!of_id)
353 return NOTIFY_OK; /* not for us */
354
355 pdev = of_find_device_by_node(np: rd->dn);
356 if (!pdev) {
357 pr_err("Could not find platform device for '%pOF'\n",
358 rd->dn);
359
360 ret = notifier_from_errno(err: -EINVAL);
361 } else {
362 of_platform_device_destroy(dev: &pdev->dev, NULL);
363 platform_device_put(pdev);
364 }
365
366 break;
367 default:
368 break;
369 }
370
371 return ret;
372}
373
374static struct notifier_block weim_of_notifier = {
375 .notifier_call = of_weim_notify,
376};
377#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
378
379static struct platform_driver weim_driver = {
380 .driver = {
381 .name = "imx-weim",
382 .of_match_table = weim_id_table,
383 },
384 .probe = weim_probe,
385};
386
387static int __init weim_init(void)
388{
389#if IS_ENABLED(CONFIG_OF_DYNAMIC)
390 WARN_ON(of_reconfig_notifier_register(&weim_of_notifier));
391#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
392
393 return platform_driver_register(&weim_driver);
394}
395module_init(weim_init);
396
397static void __exit weim_exit(void)
398{
399#if IS_ENABLED(CONFIG_OF_DYNAMIC)
400 of_reconfig_notifier_unregister(&weim_of_notifier);
401#endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */
402
403 return platform_driver_unregister(&weim_driver);
404
405}
406module_exit(weim_exit);
407
408MODULE_AUTHOR("Freescale Semiconductor Inc.");
409MODULE_DESCRIPTION("i.MX EIM Controller Driver");
410MODULE_LICENSE("GPL");
411

source code of linux/drivers/bus/imx-weim.c