xref: /openbmc/linux/arch/alpha/kernel/pci-noop.c (revision 12eb4683)
1 /*
2  *	linux/arch/alpha/kernel/pci-noop.c
3  *
4  * Stub PCI interfaces for Jensen-specific kernels.
5  */
6 
7 #include <linux/pci.h>
8 #include <linux/init.h>
9 #include <linux/bootmem.h>
10 #include <linux/gfp.h>
11 #include <linux/capability.h>
12 #include <linux/mm.h>
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/scatterlist.h>
17 
18 #include "proto.h"
19 
20 
21 /*
22  * The PCI controller list.
23  */
24 
25 struct pci_controller *hose_head, **hose_tail = &hose_head;
26 struct pci_controller *pci_isa_hose;
27 
28 
29 struct pci_controller * __init
30 alloc_pci_controller(void)
31 {
32 	struct pci_controller *hose;
33 
34 	hose = alloc_bootmem(sizeof(*hose));
35 
36 	*hose_tail = hose;
37 	hose_tail = &hose->next;
38 
39 	return hose;
40 }
41 
42 struct resource * __init
43 alloc_resource(void)
44 {
45 	struct resource *res;
46 
47 	res = alloc_bootmem(sizeof(*res));
48 
49 	return res;
50 }
51 
52 asmlinkage long
53 sys_pciconfig_iobase(long which, unsigned long bus, unsigned long dfn)
54 {
55 	struct pci_controller *hose;
56 
57 	/* from hose or from bus.devfn */
58 	if (which & IOBASE_FROM_HOSE) {
59 		for (hose = hose_head; hose; hose = hose->next)
60 			if (hose->index == bus)
61 				break;
62 		if (!hose)
63 			return -ENODEV;
64 	} else {
65 		/* Special hook for ISA access.  */
66 		if (bus == 0 && dfn == 0)
67 			hose = pci_isa_hose;
68 		else
69 			return -ENODEV;
70 	}
71 
72 	switch (which & ~IOBASE_FROM_HOSE) {
73 	case IOBASE_HOSE:
74 		return hose->index;
75 	case IOBASE_SPARSE_MEM:
76 		return hose->sparse_mem_base;
77 	case IOBASE_DENSE_MEM:
78 		return hose->dense_mem_base;
79 	case IOBASE_SPARSE_IO:
80 		return hose->sparse_io_base;
81 	case IOBASE_DENSE_IO:
82 		return hose->dense_io_base;
83 	case IOBASE_ROOT_BUS:
84 		return hose->bus->number;
85 	}
86 
87 	return -EOPNOTSUPP;
88 }
89 
90 asmlinkage long
91 sys_pciconfig_read(unsigned long bus, unsigned long dfn,
92 		   unsigned long off, unsigned long len, void *buf)
93 {
94 	if (!capable(CAP_SYS_ADMIN))
95 		return -EPERM;
96 	else
97 		return -ENODEV;
98 }
99 
100 asmlinkage long
101 sys_pciconfig_write(unsigned long bus, unsigned long dfn,
102 		    unsigned long off, unsigned long len, void *buf)
103 {
104 	if (!capable(CAP_SYS_ADMIN))
105 		return -EPERM;
106 	else
107 		return -ENODEV;
108 }
109 
110 static void *alpha_noop_alloc_coherent(struct device *dev, size_t size,
111 				       dma_addr_t *dma_handle, gfp_t gfp,
112 				       struct dma_attrs *attrs)
113 {
114 	void *ret;
115 
116 	if (!dev || *dev->dma_mask >= 0xffffffffUL)
117 		gfp &= ~GFP_DMA;
118 	ret = (void *)__get_free_pages(gfp, get_order(size));
119 	if (ret) {
120 		memset(ret, 0, size);
121 		*dma_handle = virt_to_phys(ret);
122 	}
123 	return ret;
124 }
125 
126 static void alpha_noop_free_coherent(struct device *dev, size_t size,
127 				     void *cpu_addr, dma_addr_t dma_addr,
128 				     struct dma_attrs *attrs)
129 {
130 	free_pages((unsigned long)cpu_addr, get_order(size));
131 }
132 
133 static dma_addr_t alpha_noop_map_page(struct device *dev, struct page *page,
134 				      unsigned long offset, size_t size,
135 				      enum dma_data_direction dir,
136 				      struct dma_attrs *attrs)
137 {
138 	return page_to_pa(page) + offset;
139 }
140 
141 static int alpha_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
142 			     enum dma_data_direction dir, struct dma_attrs *attrs)
143 {
144 	int i;
145 	struct scatterlist *sg;
146 
147 	for_each_sg(sgl, sg, nents, i) {
148 		void *va;
149 
150 		BUG_ON(!sg_page(sg));
151 		va = sg_virt(sg);
152 		sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va);
153 		sg_dma_len(sg) = sg->length;
154 	}
155 
156 	return nents;
157 }
158 
159 static int alpha_noop_mapping_error(struct device *dev, dma_addr_t dma_addr)
160 {
161 	return 0;
162 }
163 
164 static int alpha_noop_supported(struct device *dev, u64 mask)
165 {
166 	return mask < 0x00ffffffUL ? 0 : 1;
167 }
168 
169 static int alpha_noop_set_mask(struct device *dev, u64 mask)
170 {
171 	if (!dev->dma_mask || !dma_supported(dev, mask))
172 		return -EIO;
173 
174 	*dev->dma_mask = mask;
175 	return 0;
176 }
177 
178 struct dma_map_ops alpha_noop_ops = {
179 	.alloc			= alpha_noop_alloc_coherent,
180 	.free			= alpha_noop_free_coherent,
181 	.map_page		= alpha_noop_map_page,
182 	.map_sg			= alpha_noop_map_sg,
183 	.mapping_error		= alpha_noop_mapping_error,
184 	.dma_supported		= alpha_noop_supported,
185 	.set_dma_mask		= alpha_noop_set_mask,
186 };
187 
188 struct dma_map_ops *dma_ops = &alpha_noop_ops;
189 EXPORT_SYMBOL(dma_ops);
190