1 /*
2  * Simple allocator for internal RAM in ETRAX FS
3  *
4  * Copyright (c) 2004 Axis Communications AB.
5  */
6 
7 #include <linux/list.h>
8 #include <linux/slab.h>
9 #include <asm/io.h>
10 #include <memmap.h>
11 
12 #define STATUS_FREE 0
13 #define STATUS_ALLOCATED 1
14 
15 #ifdef CONFIG_ETRAX_L2CACHE
16 #define RESERVED_SIZE 66*1024
17 #else
18 #define RESERVED_SIZE 0
19 #endif
20 
21 struct intmem_allocation {
22 	struct list_head entry;
23 	unsigned int size;
24 	unsigned offset;
25 	char status;
26 };
27 
28 
29 static struct list_head intmem_allocations;
30 static void* intmem_virtual;
31 
crisv32_intmem_init(void)32 static void crisv32_intmem_init(void)
33 {
34 	static int initiated = 0;
35 	if (!initiated) {
36 		struct intmem_allocation* alloc;
37 		alloc = kmalloc(sizeof *alloc, GFP_KERNEL);
38 		INIT_LIST_HEAD(&intmem_allocations);
39 		intmem_virtual = ioremap(MEM_INTMEM_START + RESERVED_SIZE,
40 					 MEM_INTMEM_SIZE - RESERVED_SIZE);
41 		initiated = 1;
42 		alloc->size = MEM_INTMEM_SIZE - RESERVED_SIZE;
43 		alloc->offset = 0;
44 		alloc->status = STATUS_FREE;
45 		list_add_tail(&alloc->entry, &intmem_allocations);
46 	}
47 }
48 
crisv32_intmem_alloc(unsigned size,unsigned align)49 void* crisv32_intmem_alloc(unsigned size, unsigned align)
50 {
51 	struct intmem_allocation* allocation;
52 	struct intmem_allocation* tmp;
53 	void* ret = NULL;
54 
55 	preempt_disable();
56 	crisv32_intmem_init();
57 
58 	list_for_each_entry_safe(allocation, tmp, &intmem_allocations, entry) {
59 		int alignment = allocation->offset % align;
60 		alignment = alignment ? align - alignment : alignment;
61 
62 		if (allocation->status == STATUS_FREE &&
63 		    allocation->size >= size + alignment) {
64 			if (allocation->size > size + alignment) {
65 				struct intmem_allocation* alloc;
66 				alloc = kmalloc(sizeof *alloc, GFP_ATOMIC);
67 				alloc->status = STATUS_FREE;
68 				alloc->size = allocation->size - size -
69 					alignment;
70 				alloc->offset = allocation->offset + size +
71 					alignment;
72 				list_add(&alloc->entry, &allocation->entry);
73 
74 				if (alignment) {
75 					struct intmem_allocation *tmp;
76 					tmp = kmalloc(sizeof *tmp, GFP_ATOMIC);
77 					tmp->offset = allocation->offset;
78 					tmp->size = alignment;
79 					tmp->status = STATUS_FREE;
80 					allocation->offset += alignment;
81 					list_add_tail(&tmp->entry,
82 						&allocation->entry);
83 				}
84 			}
85 			allocation->status = STATUS_ALLOCATED;
86 			allocation->size = size;
87 			ret = (void*)((int)intmem_virtual + allocation->offset);
88 		}
89 	}
90 	preempt_enable();
91 	return ret;
92 }
93 
crisv32_intmem_free(void * addr)94 void crisv32_intmem_free(void* addr)
95 {
96 	struct intmem_allocation* allocation;
97 	struct intmem_allocation* tmp;
98 
99 	if (addr == NULL)
100 		return;
101 
102 	preempt_disable();
103 	crisv32_intmem_init();
104 
105 	list_for_each_entry_safe(allocation, tmp, &intmem_allocations, entry) {
106 		if (allocation->offset == (int)(addr - intmem_virtual)) {
107 			struct intmem_allocation *prev =
108 			  list_entry(allocation->entry.prev,
109 			             struct intmem_allocation, entry);
110 			struct intmem_allocation *next =
111 			  list_entry(allocation->entry.next,
112 				     struct intmem_allocation, entry);
113 
114 			allocation->status = STATUS_FREE;
115 			/* Join with prev and/or next if also free */
116 			if ((prev != &intmem_allocations) &&
117 					(prev->status == STATUS_FREE)) {
118 				prev->size += allocation->size;
119 				list_del(&allocation->entry);
120 				kfree(allocation);
121 				allocation = prev;
122 			}
123 			if ((next != &intmem_allocations) &&
124 					(next->status == STATUS_FREE)) {
125 				allocation->size += next->size;
126 				list_del(&next->entry);
127 				kfree(next);
128 			}
129 			preempt_enable();
130 			return;
131 		}
132 	}
133 	preempt_enable();
134 }
135 
crisv32_intmem_phys_to_virt(unsigned long addr)136 void* crisv32_intmem_phys_to_virt(unsigned long addr)
137 {
138 	return (void *)(addr - (MEM_INTMEM_START + RESERVED_SIZE) +
139 		(unsigned long)intmem_virtual);
140 }
141 
crisv32_intmem_virt_to_phys(void * addr)142 unsigned long crisv32_intmem_virt_to_phys(void* addr)
143 {
144 	return (unsigned long)((unsigned long )addr -
145 		(unsigned long)intmem_virtual + MEM_INTMEM_START +
146 		RESERVED_SIZE);
147 }
148 
149 module_init(crisv32_intmem_init);
150 
151