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/export.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/sched.h>
27 #include <linux/platform_device.h>
28 #include <linux/interrupt.h>
29 #include <linux/mod_devicetable.h>
30 #include <asm/prom.h>
31 #include <asm/fsl_lbc.h>
32 
33 static spinlock_t fsl_lbc_lock = __SPIN_LOCK_UNLOCKED(fsl_lbc_lock);
34 struct fsl_lbc_ctrl *fsl_lbc_ctrl_dev;
35 EXPORT_SYMBOL(fsl_lbc_ctrl_dev);
36 
37 /**
38  * fsl_lbc_addr - convert the base address
39  * @addr_base:	base address of the memory bank
40  *
41  * This function converts a base address of lbc into the right format for the
42  * BR register. If the SOC has eLBC then it returns 32bit physical address
43  * else it convers a 34bit local bus physical address to correct format of
44  * 32bit address for BR register (Example: MPC8641).
45  */
fsl_lbc_addr(phys_addr_t addr_base)46 u32 fsl_lbc_addr(phys_addr_t addr_base)
47 {
48 	struct device_node *np = fsl_lbc_ctrl_dev->dev->of_node;
49 	u32 addr = addr_base & 0xffff8000;
50 
51 	if (of_device_is_compatible(np, "fsl,elbc"))
52 		return addr;
53 
54 	return addr | ((addr_base & 0x300000000ull) >> 19);
55 }
56 EXPORT_SYMBOL(fsl_lbc_addr);
57 
58 /**
59  * fsl_lbc_find - find Localbus bank
60  * @addr_base:	base address of the memory bank
61  *
62  * This function walks LBC banks comparing "Base address" field of the BR
63  * registers with the supplied addr_base argument. When bases match this
64  * function returns bank number (starting with 0), otherwise it returns
65  * appropriate errno value.
66  */
fsl_lbc_find(phys_addr_t addr_base)67 int fsl_lbc_find(phys_addr_t addr_base)
68 {
69 	int i;
70 	struct fsl_lbc_regs __iomem *lbc;
71 
72 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
73 		return -ENODEV;
74 
75 	lbc = fsl_lbc_ctrl_dev->regs;
76 	for (i = 0; i < ARRAY_SIZE(lbc->bank); i++) {
77 		__be32 br = in_be32(&lbc->bank[i].br);
78 		__be32 or = in_be32(&lbc->bank[i].or);
79 
80 		if (br & BR_V && (br & or & BR_BA) == fsl_lbc_addr(addr_base))
81 			return i;
82 	}
83 
84 	return -ENOENT;
85 }
86 EXPORT_SYMBOL(fsl_lbc_find);
87 
88 /**
89  * fsl_upm_find - find pre-programmed UPM via base address
90  * @addr_base:	base address of the memory bank controlled by the UPM
91  * @upm:	pointer to the allocated fsl_upm structure
92  *
93  * This function fills fsl_upm structure so you can use it with the rest of
94  * UPM API. On success this function returns 0, otherwise it returns
95  * appropriate errno value.
96  */
fsl_upm_find(phys_addr_t addr_base,struct fsl_upm * upm)97 int fsl_upm_find(phys_addr_t addr_base, struct fsl_upm *upm)
98 {
99 	int bank;
100 	__be32 br;
101 	struct fsl_lbc_regs __iomem *lbc;
102 
103 	bank = fsl_lbc_find(addr_base);
104 	if (bank < 0)
105 		return bank;
106 
107 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
108 		return -ENODEV;
109 
110 	lbc = fsl_lbc_ctrl_dev->regs;
111 	br = in_be32(&lbc->bank[bank].br);
112 
113 	switch (br & BR_MSEL) {
114 	case BR_MS_UPMA:
115 		upm->mxmr = &lbc->mamr;
116 		break;
117 	case BR_MS_UPMB:
118 		upm->mxmr = &lbc->mbmr;
119 		break;
120 	case BR_MS_UPMC:
121 		upm->mxmr = &lbc->mcmr;
122 		break;
123 	default:
124 		return -EINVAL;
125 	}
126 
127 	switch (br & BR_PS) {
128 	case BR_PS_8:
129 		upm->width = 8;
130 		break;
131 	case BR_PS_16:
132 		upm->width = 16;
133 		break;
134 	case BR_PS_32:
135 		upm->width = 32;
136 		break;
137 	default:
138 		return -EINVAL;
139 	}
140 
141 	return 0;
142 }
143 EXPORT_SYMBOL(fsl_upm_find);
144 
145 /**
146  * fsl_upm_run_pattern - actually run an UPM pattern
147  * @upm:	pointer to the fsl_upm structure obtained via fsl_upm_find
148  * @io_base:	remapped pointer to where memory access should happen
149  * @mar:	MAR register content during pattern execution
150  *
151  * This function triggers dummy write to the memory specified by the io_base,
152  * thus UPM pattern actually executed. Note that mar usage depends on the
153  * pre-programmed AMX bits in the UPM RAM.
154  */
fsl_upm_run_pattern(struct fsl_upm * upm,void __iomem * io_base,u32 mar)155 int fsl_upm_run_pattern(struct fsl_upm *upm, void __iomem *io_base, u32 mar)
156 {
157 	int ret = 0;
158 	unsigned long flags;
159 
160 	if (!fsl_lbc_ctrl_dev || !fsl_lbc_ctrl_dev->regs)
161 		return -ENODEV;
162 
163 	spin_lock_irqsave(&fsl_lbc_lock, flags);
164 
165 	out_be32(&fsl_lbc_ctrl_dev->regs->mar, mar);
166 
167 	switch (upm->width) {
168 	case 8:
169 		out_8(io_base, 0x0);
170 		break;
171 	case 16:
172 		out_be16(io_base, 0x0);
173 		break;
174 	case 32:
175 		out_be32(io_base, 0x0);
176 		break;
177 	default:
178 		ret = -EINVAL;
179 		break;
180 	}
181 
182 	spin_unlock_irqrestore(&fsl_lbc_lock, flags);
183 
184 	return ret;
185 }
186 EXPORT_SYMBOL(fsl_upm_run_pattern);
187 
fsl_lbc_ctrl_init(struct fsl_lbc_ctrl * ctrl,struct device_node * node)188 static int __devinit fsl_lbc_ctrl_init(struct fsl_lbc_ctrl *ctrl,
189 				       struct device_node *node)
190 {
191 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
192 
193 	/* clear event registers */
194 	setbits32(&lbc->ltesr, LTESR_CLEAR);
195 	out_be32(&lbc->lteatr, 0);
196 	out_be32(&lbc->ltear, 0);
197 	out_be32(&lbc->lteccr, LTECCR_CLEAR);
198 	out_be32(&lbc->ltedr, LTEDR_ENABLE);
199 
200 	/* Set the monitor timeout value to the maximum for erratum A001 */
201 	if (of_device_is_compatible(node, "fsl,elbc"))
202 		clrsetbits_be32(&lbc->lbcr, LBCR_BMT, LBCR_BMTPS);
203 
204 	return 0;
205 }
206 
207 /*
208  * NOTE: This interrupt is used to report localbus events of various kinds,
209  * such as transaction errors on the chipselects.
210  */
211 
fsl_lbc_ctrl_irq(int irqno,void * data)212 static irqreturn_t fsl_lbc_ctrl_irq(int irqno, void *data)
213 {
214 	struct fsl_lbc_ctrl *ctrl = data;
215 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
216 	u32 status;
217 
218 	status = in_be32(&lbc->ltesr);
219 	if (!status)
220 		return IRQ_NONE;
221 
222 	out_be32(&lbc->ltesr, LTESR_CLEAR);
223 	out_be32(&lbc->lteatr, 0);
224 	out_be32(&lbc->ltear, 0);
225 	ctrl->irq_status = status;
226 
227 	if (status & LTESR_BM)
228 		dev_err(ctrl->dev, "Local bus monitor time-out: "
229 			"LTESR 0x%08X\n", status);
230 	if (status & LTESR_WP)
231 		dev_err(ctrl->dev, "Write protect error: "
232 			"LTESR 0x%08X\n", status);
233 	if (status & LTESR_ATMW)
234 		dev_err(ctrl->dev, "Atomic write error: "
235 			"LTESR 0x%08X\n", status);
236 	if (status & LTESR_ATMR)
237 		dev_err(ctrl->dev, "Atomic read error: "
238 			"LTESR 0x%08X\n", status);
239 	if (status & LTESR_CS)
240 		dev_err(ctrl->dev, "Chip select error: "
241 			"LTESR 0x%08X\n", status);
242 	if (status & LTESR_UPM)
243 		;
244 	if (status & LTESR_FCT) {
245 		dev_err(ctrl->dev, "FCM command time-out: "
246 			"LTESR 0x%08X\n", status);
247 		smp_wmb();
248 		wake_up(&ctrl->irq_wait);
249 	}
250 	if (status & LTESR_PAR) {
251 		dev_err(ctrl->dev, "Parity or Uncorrectable ECC error: "
252 			"LTESR 0x%08X\n", status);
253 		smp_wmb();
254 		wake_up(&ctrl->irq_wait);
255 	}
256 	if (status & LTESR_CC) {
257 		smp_wmb();
258 		wake_up(&ctrl->irq_wait);
259 	}
260 	if (status & ~LTESR_MASK)
261 		dev_err(ctrl->dev, "Unknown error: "
262 			"LTESR 0x%08X\n", status);
263 	return IRQ_HANDLED;
264 }
265 
266 /*
267  * fsl_lbc_ctrl_probe
268  *
269  * called by device layer when it finds a device matching
270  * one our driver can handled. This code allocates all of
271  * the resources needed for the controller only.  The
272  * resources for the NAND banks themselves are allocated
273  * in the chip probe function.
274 */
275 
fsl_lbc_ctrl_probe(struct platform_device * dev)276 static int __devinit fsl_lbc_ctrl_probe(struct platform_device *dev)
277 {
278 	int ret;
279 
280 	if (!dev->dev.of_node) {
281 		dev_err(&dev->dev, "Device OF-Node is NULL");
282 		return -EFAULT;
283 	}
284 
285 	fsl_lbc_ctrl_dev = kzalloc(sizeof(*fsl_lbc_ctrl_dev), GFP_KERNEL);
286 	if (!fsl_lbc_ctrl_dev)
287 		return -ENOMEM;
288 
289 	dev_set_drvdata(&dev->dev, fsl_lbc_ctrl_dev);
290 
291 	spin_lock_init(&fsl_lbc_ctrl_dev->lock);
292 	init_waitqueue_head(&fsl_lbc_ctrl_dev->irq_wait);
293 
294 	fsl_lbc_ctrl_dev->regs = of_iomap(dev->dev.of_node, 0);
295 	if (!fsl_lbc_ctrl_dev->regs) {
296 		dev_err(&dev->dev, "failed to get memory region\n");
297 		ret = -ENODEV;
298 		goto err;
299 	}
300 
301 	fsl_lbc_ctrl_dev->irq = irq_of_parse_and_map(dev->dev.of_node, 0);
302 	if (fsl_lbc_ctrl_dev->irq == NO_IRQ) {
303 		dev_err(&dev->dev, "failed to get irq resource\n");
304 		ret = -ENODEV;
305 		goto err;
306 	}
307 
308 	fsl_lbc_ctrl_dev->dev = &dev->dev;
309 
310 	ret = fsl_lbc_ctrl_init(fsl_lbc_ctrl_dev, dev->dev.of_node);
311 	if (ret < 0)
312 		goto err;
313 
314 	ret = request_irq(fsl_lbc_ctrl_dev->irq, fsl_lbc_ctrl_irq, 0,
315 				"fsl-lbc", fsl_lbc_ctrl_dev);
316 	if (ret != 0) {
317 		dev_err(&dev->dev, "failed to install irq (%d)\n",
318 			fsl_lbc_ctrl_dev->irq);
319 		ret = fsl_lbc_ctrl_dev->irq;
320 		goto err;
321 	}
322 
323 	/* Enable interrupts for any detected events */
324 	out_be32(&fsl_lbc_ctrl_dev->regs->lteir, LTEIR_ENABLE);
325 
326 	return 0;
327 
328 err:
329 	iounmap(fsl_lbc_ctrl_dev->regs);
330 	kfree(fsl_lbc_ctrl_dev);
331 	fsl_lbc_ctrl_dev = NULL;
332 	return ret;
333 }
334 
335 #ifdef CONFIG_SUSPEND
336 
337 /* save lbc registers */
fsl_lbc_suspend(struct platform_device * pdev,pm_message_t state)338 static int fsl_lbc_suspend(struct platform_device *pdev, pm_message_t state)
339 {
340 	struct fsl_lbc_ctrl *ctrl = dev_get_drvdata(&pdev->dev);
341 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
342 
343 	ctrl->saved_regs = kmalloc(sizeof(struct fsl_lbc_regs), GFP_KERNEL);
344 	if (!ctrl->saved_regs)
345 		return -ENOMEM;
346 
347 	_memcpy_fromio(ctrl->saved_regs, lbc, sizeof(struct fsl_lbc_regs));
348 	return 0;
349 }
350 
351 /* restore lbc registers */
fsl_lbc_resume(struct platform_device * pdev)352 static int fsl_lbc_resume(struct platform_device *pdev)
353 {
354 	struct fsl_lbc_ctrl *ctrl = dev_get_drvdata(&pdev->dev);
355 	struct fsl_lbc_regs __iomem *lbc = ctrl->regs;
356 
357 	if (ctrl->saved_regs) {
358 		_memcpy_toio(lbc, ctrl->saved_regs,
359 				sizeof(struct fsl_lbc_regs));
360 		kfree(ctrl->saved_regs);
361 		ctrl->saved_regs = NULL;
362 	}
363 	return 0;
364 }
365 #endif /* CONFIG_SUSPEND */
366 
367 static const struct of_device_id fsl_lbc_match[] = {
368 	{ .compatible = "fsl,elbc", },
369 	{ .compatible = "fsl,pq3-localbus", },
370 	{ .compatible = "fsl,pq2-localbus", },
371 	{ .compatible = "fsl,pq2pro-localbus", },
372 	{},
373 };
374 
375 static struct platform_driver fsl_lbc_ctrl_driver = {
376 	.driver = {
377 		.name = "fsl-lbc",
378 		.of_match_table = fsl_lbc_match,
379 	},
380 	.probe = fsl_lbc_ctrl_probe,
381 #ifdef CONFIG_SUSPEND
382 	.suspend     = fsl_lbc_suspend,
383 	.resume      = fsl_lbc_resume,
384 #endif
385 };
386 
fsl_lbc_init(void)387 static int __init fsl_lbc_init(void)
388 {
389 	return platform_driver_register(&fsl_lbc_ctrl_driver);
390 }
391 module_init(fsl_lbc_init);
392