1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Common CPM code
4  *
5  * Author: Scott Wood <scottwood@freescale.com>
6  *
7  * Copyright 2007-2008,2010 Freescale Semiconductor, Inc.
8  *
9  * Some parts derived from commproc.c/cpm2_common.c, which is:
10  * Copyright (c) 1997 Dan error_act (dmalek@jlc.net)
11  * Copyright (c) 1999-2001 Dan Malek <dan@embeddedalley.com>
12  * Copyright (c) 2000 MontaVista Software, Inc (source@mvista.com)
13  * 2006 (c) MontaVista Software, Inc.
14  * Vitaly Bordug <vbordug@ru.mvista.com>
15  */
16 #include <linux/genalloc.h>
17 #include <linux/init.h>
18 #include <linux/list.h>
19 #include <linux/of_device.h>
20 #include <linux/spinlock.h>
21 #include <linux/export.h>
22 #include <linux/of.h>
23 #include <linux/of_address.h>
24 #include <linux/slab.h>
25 #include <linux/io.h>
26 #include <soc/fsl/qe/qe.h>
27 
28 static struct gen_pool *muram_pool;
29 static spinlock_t cpm_muram_lock;
30 static u8 __iomem *muram_vbase;
31 static phys_addr_t muram_pbase;
32 
33 struct muram_block {
34 	struct list_head head;
35 	s32 start;
36 	int size;
37 };
38 
39 static LIST_HEAD(muram_block_list);
40 
41 /* max address size we deal with */
42 #define OF_MAX_ADDR_CELLS	4
43 #define GENPOOL_OFFSET		(4096 * 8)
44 
cpm_muram_init(void)45 int cpm_muram_init(void)
46 {
47 	struct device_node *np;
48 	struct resource r;
49 	__be32 zero[OF_MAX_ADDR_CELLS] = {};
50 	resource_size_t max = 0;
51 	int i = 0;
52 	int ret = 0;
53 
54 	if (muram_pbase)
55 		return 0;
56 
57 	spin_lock_init(&cpm_muram_lock);
58 	np = of_find_compatible_node(NULL, NULL, "fsl,cpm-muram-data");
59 	if (!np) {
60 		/* try legacy bindings */
61 		np = of_find_node_by_name(NULL, "data-only");
62 		if (!np) {
63 			pr_err("Cannot find CPM muram data node");
64 			ret = -ENODEV;
65 			goto out_muram;
66 		}
67 	}
68 
69 	muram_pool = gen_pool_create(0, -1);
70 	if (!muram_pool) {
71 		pr_err("Cannot allocate memory pool for CPM/QE muram");
72 		ret = -ENOMEM;
73 		goto out_muram;
74 	}
75 	muram_pbase = of_translate_address(np, zero);
76 	if (muram_pbase == (phys_addr_t)OF_BAD_ADDR) {
77 		pr_err("Cannot translate zero through CPM muram node");
78 		ret = -ENODEV;
79 		goto out_pool;
80 	}
81 
82 	while (of_address_to_resource(np, i++, &r) == 0) {
83 		if (r.end > max)
84 			max = r.end;
85 		ret = gen_pool_add(muram_pool, r.start - muram_pbase +
86 				   GENPOOL_OFFSET, resource_size(&r), -1);
87 		if (ret) {
88 			pr_err("QE: couldn't add muram to pool!\n");
89 			goto out_pool;
90 		}
91 	}
92 
93 	muram_vbase = ioremap(muram_pbase, max - muram_pbase + 1);
94 	if (!muram_vbase) {
95 		pr_err("Cannot map QE muram");
96 		ret = -ENOMEM;
97 		goto out_pool;
98 	}
99 	goto out_muram;
100 out_pool:
101 	gen_pool_destroy(muram_pool);
102 out_muram:
103 	of_node_put(np);
104 	return ret;
105 }
106 
107 /*
108  * cpm_muram_alloc_common - cpm_muram_alloc common code
109  * @size: number of bytes to allocate
110  * @algo: algorithm for alloc.
111  * @data: data for genalloc's algorithm.
112  *
113  * This function returns a non-negative offset into the muram area, or
114  * a negative errno on failure.
115  */
cpm_muram_alloc_common(unsigned long size,genpool_algo_t algo,void * data)116 static s32 cpm_muram_alloc_common(unsigned long size,
117 				  genpool_algo_t algo, void *data)
118 {
119 	struct muram_block *entry;
120 	s32 start;
121 
122 	entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
123 	if (!entry)
124 		return -ENOMEM;
125 	start = gen_pool_alloc_algo(muram_pool, size, algo, data);
126 	if (!start) {
127 		kfree(entry);
128 		return -ENOMEM;
129 	}
130 	start = start - GENPOOL_OFFSET;
131 	memset_io(cpm_muram_addr(start), 0, size);
132 	entry->start = start;
133 	entry->size = size;
134 	list_add(&entry->head, &muram_block_list);
135 
136 	return start;
137 }
138 
139 /*
140  * cpm_muram_alloc - allocate the requested size worth of multi-user ram
141  * @size: number of bytes to allocate
142  * @align: requested alignment, in bytes
143  *
144  * This function returns a non-negative offset into the muram area, or
145  * a negative errno on failure.
146  * Use cpm_dpram_addr() to get the virtual address of the area.
147  * Use cpm_muram_free() to free the allocation.
148  */
cpm_muram_alloc(unsigned long size,unsigned long align)149 s32 cpm_muram_alloc(unsigned long size, unsigned long align)
150 {
151 	s32 start;
152 	unsigned long flags;
153 	struct genpool_data_align muram_pool_data;
154 
155 	spin_lock_irqsave(&cpm_muram_lock, flags);
156 	muram_pool_data.align = align;
157 	start = cpm_muram_alloc_common(size, gen_pool_first_fit_align,
158 				       &muram_pool_data);
159 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
160 	return start;
161 }
162 EXPORT_SYMBOL(cpm_muram_alloc);
163 
164 /**
165  * cpm_muram_free - free a chunk of multi-user ram
166  * @offset: The beginning of the chunk as returned by cpm_muram_alloc().
167  */
cpm_muram_free(s32 offset)168 void cpm_muram_free(s32 offset)
169 {
170 	unsigned long flags;
171 	int size;
172 	struct muram_block *tmp;
173 
174 	if (offset < 0)
175 		return;
176 
177 	size = 0;
178 	spin_lock_irqsave(&cpm_muram_lock, flags);
179 	list_for_each_entry(tmp, &muram_block_list, head) {
180 		if (tmp->start == offset) {
181 			size = tmp->size;
182 			list_del(&tmp->head);
183 			kfree(tmp);
184 			break;
185 		}
186 	}
187 	gen_pool_free(muram_pool, offset + GENPOOL_OFFSET, size);
188 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
189 }
190 EXPORT_SYMBOL(cpm_muram_free);
191 
192 /*
193  * cpm_muram_alloc_fixed - reserve a specific region of multi-user ram
194  * @offset: offset of allocation start address
195  * @size: number of bytes to allocate
196  * This function returns @offset if the area was available, a negative
197  * errno otherwise.
198  * Use cpm_dpram_addr() to get the virtual address of the area.
199  * Use cpm_muram_free() to free the allocation.
200  */
cpm_muram_alloc_fixed(unsigned long offset,unsigned long size)201 s32 cpm_muram_alloc_fixed(unsigned long offset, unsigned long size)
202 {
203 	s32 start;
204 	unsigned long flags;
205 	struct genpool_data_fixed muram_pool_data_fixed;
206 
207 	spin_lock_irqsave(&cpm_muram_lock, flags);
208 	muram_pool_data_fixed.offset = offset + GENPOOL_OFFSET;
209 	start = cpm_muram_alloc_common(size, gen_pool_fixed_alloc,
210 				       &muram_pool_data_fixed);
211 	spin_unlock_irqrestore(&cpm_muram_lock, flags);
212 	return start;
213 }
214 EXPORT_SYMBOL(cpm_muram_alloc_fixed);
215 
216 /**
217  * cpm_muram_addr - turn a muram offset into a virtual address
218  * @offset: muram offset to convert
219  */
cpm_muram_addr(unsigned long offset)220 void __iomem *cpm_muram_addr(unsigned long offset)
221 {
222 	return muram_vbase + offset;
223 }
224 EXPORT_SYMBOL(cpm_muram_addr);
225 
cpm_muram_offset(void __iomem * addr)226 unsigned long cpm_muram_offset(void __iomem *addr)
227 {
228 	return addr - (void __iomem *)muram_vbase;
229 }
230 EXPORT_SYMBOL(cpm_muram_offset);
231 
232 /**
233  * cpm_muram_dma - turn a muram virtual address into a DMA address
234  * @offset: virtual address from cpm_muram_addr() to convert
235  */
cpm_muram_dma(void __iomem * addr)236 dma_addr_t cpm_muram_dma(void __iomem *addr)
237 {
238 	return muram_pbase + ((u8 __iomem *)addr - muram_vbase);
239 }
240 EXPORT_SYMBOL(cpm_muram_dma);
241