1 /*
2  * Freescale LBC and UPM routines.
3  *
4  * Copyright © 2007-2008  MontaVista Software, Inc.
5  * Copyright © 2010 Freescale Semiconductor
6  *
7  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
8  * Author: Jack Lan <Jack.Lan@freescale.com>
9  * Author: Roy Zang <tie-fei.zang@freescale.com>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  */
16 
17 #include <linux/init.h>
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/compiler.h>
21 #include <linux/spinlock.h>
22 #include <linux/types.h>
23 #include <linux/io.h>
24 #include <linux/of.h>
25 #include <linux/slab.h>
26 #include <linux/platform_device.h>
27 #include <linux/interrupt.h>
28 #include <linux/mod_devicetable.h>
29 #include <asm/prom.h>
30 #include <asm/fsl_lbc.h>
31 
32 static spinlock_t fsl_lbc_lock = __SPIN_LOCK_UNLOCKED(fsl_lbc_lock);
33 struct fsl_lbc_ctrl *fsl_lbc_ctrl_dev;
34 EXPORT_SYMBOL(fsl_lbc_ctrl_dev);
35 
36 /**
37  * fsl_lbc_addr - convert the base address
38  * @addr_base:	base address of the memory bank
39  *
40  * This function converts a base address of lbc into the right format for the
41  * BR register. If the SOC has eLBC then it returns 32bit physical address
42  * else it convers a 34bit local bus physical address to correct format of
43  * 32bit address for BR register (Example: MPC8641).
44  */
fsl_lbc_addr(phys_addr_t addr_base)45 u32 fsl_lbc_addr(phys_addr_t addr_base)
46 {
47 	struct device_node *np = fsl_lbc_ctrl_dev->dev->of_node;
48 	u32 addr = addr_base & 0xffff8000;
49 
50 	if (of_device_is_compatible(np, "fsl,elbc"))
51 		return addr;
52 
53 	return addr | ((addr_base & 0x300000000ull) >> 19);
54 }
55 EXPORT_SYMBOL(fsl_lbc_addr);
56 
57 /**
58  * fsl_lbc_find - find Localbus bank
59  * @addr_base:	base address of the memory bank
60  *
61  * This function walks LBC banks comparing "Base address" field of the BR
62  * registers with the supplied addr_base argument. When bases match this
63  * function returns bank number (starting with 0), otherwise it returns
64  * appropriate errno value.
65  */
fsl_lbc_find(phys_addr_t addr_base)66 int fsl_lbc_find(phys_addr_t addr_base)
67 {
68 	int i;
69 	struct fsl_lbc_regs __iomem *lbc;
70 
71 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
72 		return -ENODEV;
73 
74 	lbc = fsl_lbc_ctrl_dev->regs;
75 	for (i = 0; i < ARRAY_SIZE(lbc->bank); i++) {
76 		__be32 br = in_be32(&lbc->bank[i].br);
77 		__be32 or = in_be32(&lbc->bank[i].or);
78 
79 		if (br & BR_V && (br & or & BR_BA) == fsl_lbc_addr(addr_base))
80 			return i;
81 	}
82 
83 	return -ENOENT;
84 }
85 EXPORT_SYMBOL(fsl_lbc_find);
86 
87 /**
88  * fsl_upm_find - find pre-programmed UPM via base address
89  * @addr_base:	base address of the memory bank controlled by the UPM
90  * @upm:	pointer to the allocated fsl_upm structure
91  *
92  * This function fills fsl_upm structure so you can use it with the rest of
93  * UPM API. On success this function returns 0, otherwise it returns
94  * appropriate errno value.
95  */
fsl_upm_find(phys_addr_t addr_base,struct fsl_upm * upm)96 int fsl_upm_find(phys_addr_t addr_base, struct fsl_upm *upm)
97 {
98 	int bank;
99 	__be32 br;
100 	struct fsl_lbc_regs __iomem *lbc;
101 
102 	bank = fsl_lbc_find(addr_base);
103 	if (bank < 0)
104 		return bank;
105 
106 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
107 		return -ENODEV;
108 
109 	lbc = fsl_lbc_ctrl_dev->regs;
110 	br = in_be32(&lbc->bank[bank].br);
111 
112 	switch (br & BR_MSEL) {
113 	case BR_MS_UPMA:
114 		upm->mxmr = &lbc->mamr;
115 		break;
116 	case BR_MS_UPMB:
117 		upm->mxmr = &lbc->mbmr;
118 		break;
119 	case BR_MS_UPMC:
120 		upm->mxmr = &lbc->mcmr;
121 		break;
122 	default:
123 		return -EINVAL;
124 	}
125 
126 	switch (br & BR_PS) {
127 	case BR_PS_8:
128 		upm->width = 8;
129 		break;
130 	case BR_PS_16:
131 		upm->width = 16;
132 		break;
133 	case BR_PS_32:
134 		upm->width = 32;
135 		break;
136 	default:
137 		return -EINVAL;
138 	}
139 
140 	return 0;
141 }
142 EXPORT_SYMBOL(fsl_upm_find);
143 
144 /**
145  * fsl_upm_run_pattern - actually run an UPM pattern
146  * @upm:	pointer to the fsl_upm structure obtained via fsl_upm_find
147  * @io_base:	remapped pointer to where memory access should happen
148  * @mar:	MAR register content during pattern execution
149  *
150  * This function triggers dummy write to the memory specified by the io_base,
151  * thus UPM pattern actually executed. Note that mar usage depends on the
152  * pre-programmed AMX bits in the UPM RAM.
153  */
fsl_upm_run_pattern(struct fsl_upm * upm,void __iomem * io_base,u32 mar)154 int fsl_upm_run_pattern(struct fsl_upm *upm, void __iomem *io_base, u32 mar)
155 {
156 	int ret = 0;
157 	unsigned long flags;
158 
159 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
160 		return -ENODEV;
161 
162 	spin_lock_irqsave(&fsl_lbc_lock, flags);
163 
164 	out_be32(&fsl_lbc_ctrl_dev->regs->mar, mar);
165 
166 	switch (upm->width) {
167 	case 8:
168 		out_8(io_base, 0x0);
169 		break;
170 	case 16:
171 		out_be16(io_base, 0x0);
172 		break;
173 	case 32:
174 		out_be32(io_base, 0x0);
175 		break;
176 	default:
177 		ret = -EINVAL;
178 		break;
179 	}
180 
181 	spin_unlock_irqrestore(&fsl_lbc_lock, flags);
182 
183 	return ret;
184 }
185 EXPORT_SYMBOL(fsl_upm_run_pattern);
186 
fsl_lbc_ctrl_init(struct fsl_lbc_ctrl * ctrl)187 static int __devinit fsl_lbc_ctrl_init(struct fsl_lbc_ctrl *ctrl)
188 {
189 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
190 
191 	/* clear event registers */
192 	setbits32(&lbc->ltesr, LTESR_CLEAR);
193 	out_be32(&lbc->lteatr, 0);
194 	out_be32(&lbc->ltear, 0);
195 	out_be32(&lbc->lteccr, LTECCR_CLEAR);
196 	out_be32(&lbc->ltedr, LTEDR_ENABLE);
197 
198 	/* Enable interrupts for any detected events */
199 	out_be32(&lbc->lteir, LTEIR_ENABLE);
200 
201 	return 0;
202 }
203 
204 /*
205  * NOTE: This interrupt is used to report localbus events of various kinds,
206  * such as transaction errors on the chipselects.
207  */
208 
fsl_lbc_ctrl_irq(int irqno,void * data)209 static irqreturn_t fsl_lbc_ctrl_irq(int irqno, void *data)
210 {
211 	struct fsl_lbc_ctrl *ctrl = data;
212 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
213 	u32 status;
214 
215 	status = in_be32(&lbc->ltesr);
216 	if (!status)
217 		return IRQ_NONE;
218 
219 	out_be32(&lbc->ltesr, LTESR_CLEAR);
220 	out_be32(&lbc->lteatr, 0);
221 	out_be32(&lbc->ltear, 0);
222 	ctrl->irq_status = status;
223 
224 	if (status & LTESR_BM)
225 		dev_err(ctrl->dev, "Local bus monitor time-out: "
226 			"LTESR 0x%08X\n", status);
227 	if (status & LTESR_WP)
228 		dev_err(ctrl->dev, "Write protect error: "
229 			"LTESR 0x%08X\n", status);
230 	if (status & LTESR_ATMW)
231 		dev_err(ctrl->dev, "Atomic write error: "
232 			"LTESR 0x%08X\n", status);
233 	if (status & LTESR_ATMR)
234 		dev_err(ctrl->dev, "Atomic read error: "
235 			"LTESR 0x%08X\n", status);
236 	if (status & LTESR_CS)
237 		dev_err(ctrl->dev, "Chip select error: "
238 			"LTESR 0x%08X\n", status);
239 	if (status & LTESR_UPM)
240 		;
241 	if (status & LTESR_FCT) {
242 		dev_err(ctrl->dev, "FCM command time-out: "
243 			"LTESR 0x%08X\n", status);
244 		smp_wmb();
245 		wake_up(&ctrl->irq_wait);
246 	}
247 	if (status & LTESR_PAR) {
248 		dev_err(ctrl->dev, "Parity or Uncorrectable ECC error: "
249 			"LTESR 0x%08X\n", status);
250 		smp_wmb();
251 		wake_up(&ctrl->irq_wait);
252 	}
253 	if (status & LTESR_CC) {
254 		smp_wmb();
255 		wake_up(&ctrl->irq_wait);
256 	}
257 	if (status & ~LTESR_MASK)
258 		dev_err(ctrl->dev, "Unknown error: "
259 			"LTESR 0x%08X\n", status);
260 	return IRQ_HANDLED;
261 }
262 
263 /*
264  * fsl_lbc_ctrl_probe
265  *
266  * called by device layer when it finds a device matching
267  * one our driver can handled. This code allocates all of
268  * the resources needed for the controller only.  The
269  * resources for the NAND banks themselves are allocated
270  * in the chip probe function.
271 */
272 
fsl_lbc_ctrl_probe(struct platform_device * dev)273 static int __devinit fsl_lbc_ctrl_probe(struct platform_device *dev)
274 {
275 	int ret;
276 
277 	if (!dev->dev.of_node) {
278 		dev_err(&dev->dev, "Device OF-Node is NULL");
279 		return -EFAULT;
280 	}
281 
282 	fsl_lbc_ctrl_dev = kzalloc(sizeof(*fsl_lbc_ctrl_dev), GFP_KERNEL);
283 	if (!fsl_lbc_ctrl_dev)
284 		return -ENOMEM;
285 
286 	dev_set_drvdata(&dev->dev, fsl_lbc_ctrl_dev);
287 
288 	spin_lock_init(&fsl_lbc_ctrl_dev->lock);
289 	init_waitqueue_head(&fsl_lbc_ctrl_dev->irq_wait);
290 
291 	fsl_lbc_ctrl_dev->regs = of_iomap(dev->dev.of_node, 0);
292 	if (!fsl_lbc_ctrl_dev->regs) {
293 		dev_err(&dev->dev, "failed to get memory region\n");
294 		ret = -ENODEV;
295 		goto err;
296 	}
297 
298 	fsl_lbc_ctrl_dev->irq = irq_of_parse_and_map(dev->dev.of_node, 0);
299 	if (fsl_lbc_ctrl_dev->irq == NO_IRQ) {
300 		dev_err(&dev->dev, "failed to get irq resource\n");
301 		ret = -ENODEV;
302 		goto err;
303 	}
304 
305 	fsl_lbc_ctrl_dev->dev = &dev->dev;
306 
307 	ret = fsl_lbc_ctrl_init(fsl_lbc_ctrl_dev);
308 	if (ret < 0)
309 		goto err;
310 
311 	ret = request_irq(fsl_lbc_ctrl_dev->irq, fsl_lbc_ctrl_irq, 0,
312 				"fsl-lbc", fsl_lbc_ctrl_dev);
313 	if (ret != 0) {
314 		dev_err(&dev->dev, "failed to install irq (%d)\n",
315 			fsl_lbc_ctrl_dev->irq);
316 		ret = fsl_lbc_ctrl_dev->irq;
317 		goto err;
318 	}
319 
320 	return 0;
321 
322 err:
323 	iounmap(fsl_lbc_ctrl_dev->regs);
324 	kfree(fsl_lbc_ctrl_dev);
325 	return ret;
326 }
327 
328 static const struct of_device_id fsl_lbc_match[] = {
329 	{ .compatible = "fsl,elbc", },
330 	{ .compatible = "fsl,pq3-localbus", },
331 	{ .compatible = "fsl,pq2-localbus", },
332 	{ .compatible = "fsl,pq2pro-localbus", },
333 	{},
334 };
335 
336 static struct platform_driver fsl_lbc_ctrl_driver = {
337 	.driver = {
338 		.name = "fsl-lbc",
339 		.of_match_table = fsl_lbc_match,
340 	},
341 	.probe = fsl_lbc_ctrl_probe,
342 };
343 
fsl_lbc_init(void)344 static int __init fsl_lbc_init(void)
345 {
346 	return platform_driver_register(&fsl_lbc_ctrl_driver);
347 }
348 module_init(fsl_lbc_init);
349