1 /*
2  * Common CPM code
3  *
4  * Author: Scott Wood <scottwood@freescale.com>
5  *
6  * Copyright 2007 Freescale Semiconductor, Inc.
7  *
8  * Some parts derived from commproc.c/cpm2_common.c, which is:
9  * Copyright (c) 1997 Dan error_act (dmalek@jlc.net)
10  * Copyright (c) 1999-2001 Dan Malek <dan@embeddedalley.com>
11  * Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com)
12  * 2006 (c) MontaVista Software, Inc.
13  * Vitaly Bordug <vbordug@ru.mvista.com>
14  *
15  * This program is free software; you can redistribute it and/or modify
16  * it under the terms of version 2 of the GNU General Public License as
17  * published by the Free Software Foundation.
18  */
19 
20 #include <linux/init.h>
21 #include <linux/of_device.h>
22 #include <linux/spinlock.h>
23 #include <linux/of.h>
24 #include <linux/slab.h>
25 
26 #include <asm/udbg.h>
27 #include <asm/io.h>
28 #include <asm/system.h>
29 #include <asm/rheap.h>
30 #include <asm/cpm.h>
31 
32 #include <mm/mmu_decl.h>
33 
34 #if defined(CONFIG_CPM2) || defined(CONFIG_8xx_GPIO)
35 #include <linux/of_gpio.h>
36 #endif
37 
38 #ifdef CONFIG_PPC_EARLY_DEBUG_CPM
39 static u32 __iomem *cpm_udbg_txdesc =
40 	(u32 __iomem __force *)CONFIG_PPC_EARLY_DEBUG_CPM_ADDR;
41 
udbg_putc_cpm(char c)42 static void udbg_putc_cpm(char c)
43 {
44 	u8 __iomem *txbuf = (u8 __iomem __force *)in_be32(&cpm_udbg_txdesc[1]);
45 
46 	if (c == '\n')
47 		udbg_putc_cpm('\r');
48 
49 	while (in_be32(&cpm_udbg_txdesc[0]) & 0x80000000)
50 		;
51 
52 	out_8(txbuf, c);
53 	out_be32(&cpm_udbg_txdesc[0], 0xa0000001);
54 }
55 
udbg_init_cpm(void)56 void __init udbg_init_cpm(void)
57 {
58 	if (cpm_udbg_txdesc) {
59 #ifdef CONFIG_CPM2
60 		setbat(1, 0xf0000000, 0xf0000000, 1024*1024, PAGE_KERNEL_NCG);
61 #endif
62 		udbg_putc = udbg_putc_cpm;
63 	}
64 }
65 #endif
66 
67 static spinlock_t cpm_muram_lock;
68 static rh_block_t cpm_boot_muram_rh_block[16];
69 static rh_info_t cpm_muram_info;
70 static u8 __iomem *muram_vbase;
71 static phys_addr_t muram_pbase;
72 
73 /* Max address size we deal with */
74 #define OF_MAX_ADDR_CELLS	4
75 
cpm_muram_init(void)76 int cpm_muram_init(void)
77 {
78 	struct device_node *np;
79 	struct resource r;
80 	u32 zero[OF_MAX_ADDR_CELLS] = {};
81 	resource_size_t max = 0;
82 	int i = 0;
83 	int ret = 0;
84 
85 	if (muram_pbase)
86 		return 0;
87 
88 	spin_lock_init(&cpm_muram_lock);
89 	/* initialize the info header */
90 	rh_init(&cpm_muram_info, 1,
91 	        sizeof(cpm_boot_muram_rh_block) /
92 	        sizeof(cpm_boot_muram_rh_block[0]),
93 	        cpm_boot_muram_rh_block);
94 
95 	np = of_find_compatible_node(NULL, NULL, "fsl,cpm-muram-data");
96 	if (!np) {
97 		/* try legacy bindings */
98 		np = of_find_node_by_name(NULL, "data-only");
99 		if (!np) {
100 			printk(KERN_ERR "Cannot find CPM muram data node");
101 			ret = -ENODEV;
102 			goto out;
103 		}
104 	}
105 
106 	muram_pbase = of_translate_address(np, zero);
107 	if (muram_pbase == (phys_addr_t)OF_BAD_ADDR) {
108 		printk(KERN_ERR "Cannot translate zero through CPM muram node");
109 		ret = -ENODEV;
110 		goto out;
111 	}
112 
113 	while (of_address_to_resource(np, i++, &r) == 0) {
114 		if (r.end > max)
115 			max = r.end;
116 
117 		rh_attach_region(&cpm_muram_info, r.start - muram_pbase,
118 		                 r.end - r.start + 1);
119 	}
120 
121 	muram_vbase = ioremap(muram_pbase, max - muram_pbase + 1);
122 	if (!muram_vbase) {
123 		printk(KERN_ERR "Cannot map CPM muram");
124 		ret = -ENOMEM;
125 	}
126 
127 out:
128 	of_node_put(np);
129 	return ret;
130 }
131 
132 /**
133  * cpm_muram_alloc - allocate the requested size worth of multi-user ram
134  * @size: number of bytes to allocate
135  * @align: requested alignment, in bytes
136  *
137  * This function returns an offset into the muram area.
138  * Use cpm_dpram_addr() to get the virtual address of the area.
139  * Use cpm_muram_free() to free the allocation.
140  */
cpm_muram_alloc(unsigned long size,unsigned long align)141 unsigned long cpm_muram_alloc(unsigned long size, unsigned long align)
142 {
143 	unsigned long start;
144 	unsigned long flags;
145 
146 	spin_lock_irqsave(&cpm_muram_lock, flags);
147 	cpm_muram_info.alignment = align;
148 	start = rh_alloc(&cpm_muram_info, size, "commproc");
149 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
150 
151 	return start;
152 }
153 EXPORT_SYMBOL(cpm_muram_alloc);
154 
155 /**
156  * cpm_muram_free - free a chunk of multi-user ram
157  * @offset: The beginning of the chunk as returned by cpm_muram_alloc().
158  */
cpm_muram_free(unsigned long offset)159 int cpm_muram_free(unsigned long offset)
160 {
161 	int ret;
162 	unsigned long flags;
163 
164 	spin_lock_irqsave(&cpm_muram_lock, flags);
165 	ret = rh_free(&cpm_muram_info, offset);
166 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
167 
168 	return ret;
169 }
170 EXPORT_SYMBOL(cpm_muram_free);
171 
172 /**
173  * cpm_muram_alloc_fixed - reserve a specific region of multi-user ram
174  * @offset: the offset into the muram area to reserve
175  * @size: the number of bytes to reserve
176  *
177  * This function returns "start" on success, -ENOMEM on failure.
178  * Use cpm_dpram_addr() to get the virtual address of the area.
179  * Use cpm_muram_free() to free the allocation.
180  */
cpm_muram_alloc_fixed(unsigned long offset,unsigned long size)181 unsigned long cpm_muram_alloc_fixed(unsigned long offset, unsigned long size)
182 {
183 	unsigned long start;
184 	unsigned long flags;
185 
186 	spin_lock_irqsave(&cpm_muram_lock, flags);
187 	cpm_muram_info.alignment = 1;
188 	start = rh_alloc_fixed(&cpm_muram_info, offset, size, "commproc");
189 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
190 
191 	return start;
192 }
193 EXPORT_SYMBOL(cpm_muram_alloc_fixed);
194 
195 /**
196  * cpm_muram_addr - turn a muram offset into a virtual address
197  * @offset: muram offset to convert
198  */
cpm_muram_addr(unsigned long offset)199 void __iomem *cpm_muram_addr(unsigned long offset)
200 {
201 	return muram_vbase + offset;
202 }
203 EXPORT_SYMBOL(cpm_muram_addr);
204 
cpm_muram_offset(void __iomem * addr)205 unsigned long cpm_muram_offset(void __iomem *addr)
206 {
207 	return addr - (void __iomem *)muram_vbase;
208 }
209 EXPORT_SYMBOL(cpm_muram_offset);
210 
211 /**
212  * cpm_muram_dma - turn a muram virtual address into a DMA address
213  * @offset: virtual address from cpm_muram_addr() to convert
214  */
cpm_muram_dma(void __iomem * addr)215 dma_addr_t cpm_muram_dma(void __iomem *addr)
216 {
217 	return muram_pbase + ((u8 __iomem *)addr - muram_vbase);
218 }
219 EXPORT_SYMBOL(cpm_muram_dma);
220 
221 #if defined(CONFIG_CPM2) || defined(CONFIG_8xx_GPIO)
222 
223 struct cpm2_ioports {
224 	u32 dir, par, sor, odr, dat;
225 	u32 res[3];
226 };
227 
228 struct cpm2_gpio32_chip {
229 	struct of_mm_gpio_chip mm_gc;
230 	spinlock_t lock;
231 
232 	/* shadowed data register to clear/set bits safely */
233 	u32 cpdata;
234 };
235 
236 static inline struct cpm2_gpio32_chip *
to_cpm2_gpio32_chip(struct of_mm_gpio_chip * mm_gc)237 to_cpm2_gpio32_chip(struct of_mm_gpio_chip *mm_gc)
238 {
239 	return container_of(mm_gc, struct cpm2_gpio32_chip, mm_gc);
240 }
241 
cpm2_gpio32_save_regs(struct of_mm_gpio_chip * mm_gc)242 static void cpm2_gpio32_save_regs(struct of_mm_gpio_chip *mm_gc)
243 {
244 	struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
245 	struct cpm2_ioports __iomem *iop = mm_gc->regs;
246 
247 	cpm2_gc->cpdata = in_be32(&iop->dat);
248 }
249 
cpm2_gpio32_get(struct gpio_chip * gc,unsigned int gpio)250 static int cpm2_gpio32_get(struct gpio_chip *gc, unsigned int gpio)
251 {
252 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
253 	struct cpm2_ioports __iomem *iop = mm_gc->regs;
254 	u32 pin_mask;
255 
256 	pin_mask = 1 << (31 - gpio);
257 
258 	return !!(in_be32(&iop->dat) & pin_mask);
259 }
260 
__cpm2_gpio32_set(struct of_mm_gpio_chip * mm_gc,u32 pin_mask,int value)261 static void __cpm2_gpio32_set(struct of_mm_gpio_chip *mm_gc, u32 pin_mask,
262 	int value)
263 {
264 	struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
265 	struct cpm2_ioports __iomem *iop = mm_gc->regs;
266 
267 	if (value)
268 		cpm2_gc->cpdata |= pin_mask;
269 	else
270 		cpm2_gc->cpdata &= ~pin_mask;
271 
272 	out_be32(&iop->dat, cpm2_gc->cpdata);
273 }
274 
cpm2_gpio32_set(struct gpio_chip * gc,unsigned int gpio,int value)275 static void cpm2_gpio32_set(struct gpio_chip *gc, unsigned int gpio, int value)
276 {
277 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
278 	struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
279 	unsigned long flags;
280 	u32 pin_mask = 1 << (31 - gpio);
281 
282 	spin_lock_irqsave(&cpm2_gc->lock, flags);
283 
284 	__cpm2_gpio32_set(mm_gc, pin_mask, value);
285 
286 	spin_unlock_irqrestore(&cpm2_gc->lock, flags);
287 }
288 
cpm2_gpio32_dir_out(struct gpio_chip * gc,unsigned int gpio,int val)289 static int cpm2_gpio32_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
290 {
291 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
292 	struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
293 	struct cpm2_ioports __iomem *iop = mm_gc->regs;
294 	unsigned long flags;
295 	u32 pin_mask = 1 << (31 - gpio);
296 
297 	spin_lock_irqsave(&cpm2_gc->lock, flags);
298 
299 	setbits32(&iop->dir, pin_mask);
300 	__cpm2_gpio32_set(mm_gc, pin_mask, val);
301 
302 	spin_unlock_irqrestore(&cpm2_gc->lock, flags);
303 
304 	return 0;
305 }
306 
cpm2_gpio32_dir_in(struct gpio_chip * gc,unsigned int gpio)307 static int cpm2_gpio32_dir_in(struct gpio_chip *gc, unsigned int gpio)
308 {
309 	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
310 	struct cpm2_gpio32_chip *cpm2_gc = to_cpm2_gpio32_chip(mm_gc);
311 	struct cpm2_ioports __iomem *iop = mm_gc->regs;
312 	unsigned long flags;
313 	u32 pin_mask = 1 << (31 - gpio);
314 
315 	spin_lock_irqsave(&cpm2_gc->lock, flags);
316 
317 	clrbits32(&iop->dir, pin_mask);
318 
319 	spin_unlock_irqrestore(&cpm2_gc->lock, flags);
320 
321 	return 0;
322 }
323 
cpm2_gpiochip_add32(struct device_node * np)324 int cpm2_gpiochip_add32(struct device_node *np)
325 {
326 	struct cpm2_gpio32_chip *cpm2_gc;
327 	struct of_mm_gpio_chip *mm_gc;
328 	struct gpio_chip *gc;
329 
330 	cpm2_gc = kzalloc(sizeof(*cpm2_gc), GFP_KERNEL);
331 	if (!cpm2_gc)
332 		return -ENOMEM;
333 
334 	spin_lock_init(&cpm2_gc->lock);
335 
336 	mm_gc = &cpm2_gc->mm_gc;
337 	gc = &mm_gc->gc;
338 
339 	mm_gc->save_regs = cpm2_gpio32_save_regs;
340 	gc->ngpio = 32;
341 	gc->direction_input = cpm2_gpio32_dir_in;
342 	gc->direction_output = cpm2_gpio32_dir_out;
343 	gc->get = cpm2_gpio32_get;
344 	gc->set = cpm2_gpio32_set;
345 
346 	return of_mm_gpiochip_add(np, mm_gc);
347 }
348 #endif /* CONFIG_CPM2 || CONFIG_8xx_GPIO */
349