xref: /openbmc/linux/arch/alpha/kernel/pci-noop.c (revision d2ba09c1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/pci-noop.c
4  *
5  * Stub PCI interfaces for Jensen-specific kernels.
6  */
7 
8 #include <linux/pci.h>
9 #include <linux/init.h>
10 #include <linux/bootmem.h>
11 #include <linux/gfp.h>
12 #include <linux/capability.h>
13 #include <linux/mm.h>
14 #include <linux/errno.h>
15 #include <linux/sched.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/scatterlist.h>
18 #include <linux/syscalls.h>
19 
20 #include "proto.h"
21 
22 
23 /*
24  * The PCI controller list.
25  */
26 
27 struct pci_controller *hose_head, **hose_tail = &hose_head;
28 struct pci_controller *pci_isa_hose;
29 
30 
31 struct pci_controller * __init
32 alloc_pci_controller(void)
33 {
34 	struct pci_controller *hose;
35 
36 	hose = alloc_bootmem(sizeof(*hose));
37 
38 	*hose_tail = hose;
39 	hose_tail = &hose->next;
40 
41 	return hose;
42 }
43 
44 struct resource * __init
45 alloc_resource(void)
46 {
47 	return alloc_bootmem(sizeof(struct resource));
48 }
49 
50 SYSCALL_DEFINE3(pciconfig_iobase, long, which, unsigned long, bus,
51 		unsigned long, dfn)
52 {
53 	struct pci_controller *hose;
54 
55 	/* from hose or from bus.devfn */
56 	if (which & IOBASE_FROM_HOSE) {
57 		for (hose = hose_head; hose; hose = hose->next)
58 			if (hose->index == bus)
59 				break;
60 		if (!hose)
61 			return -ENODEV;
62 	} else {
63 		/* Special hook for ISA access.  */
64 		if (bus == 0 && dfn == 0)
65 			hose = pci_isa_hose;
66 		else
67 			return -ENODEV;
68 	}
69 
70 	switch (which & ~IOBASE_FROM_HOSE) {
71 	case IOBASE_HOSE:
72 		return hose->index;
73 	case IOBASE_SPARSE_MEM:
74 		return hose->sparse_mem_base;
75 	case IOBASE_DENSE_MEM:
76 		return hose->dense_mem_base;
77 	case IOBASE_SPARSE_IO:
78 		return hose->sparse_io_base;
79 	case IOBASE_DENSE_IO:
80 		return hose->dense_io_base;
81 	case IOBASE_ROOT_BUS:
82 		return hose->bus->number;
83 	}
84 
85 	return -EOPNOTSUPP;
86 }
87 
88 SYSCALL_DEFINE5(pciconfig_read, unsigned long, bus, unsigned long, dfn,
89 		unsigned long, off, unsigned long, len, void __user *, buf)
90 {
91 	if (!capable(CAP_SYS_ADMIN))
92 		return -EPERM;
93 	else
94 		return -ENODEV;
95 }
96 
97 SYSCALL_DEFINE5(pciconfig_write, unsigned long, bus, unsigned long, dfn,
98 		unsigned long, off, unsigned long, len, void __user *, buf)
99 {
100 	if (!capable(CAP_SYS_ADMIN))
101 		return -EPERM;
102 	else
103 		return -ENODEV;
104 }
105 
106 static void *alpha_noop_alloc_coherent(struct device *dev, size_t size,
107 				       dma_addr_t *dma_handle, gfp_t gfp,
108 				       unsigned long attrs)
109 {
110 	void *ret;
111 
112 	if (!dev || *dev->dma_mask >= 0xffffffffUL)
113 		gfp &= ~GFP_DMA;
114 	ret = (void *)__get_free_pages(gfp, get_order(size));
115 	if (ret) {
116 		memset(ret, 0, size);
117 		*dma_handle = virt_to_phys(ret);
118 	}
119 	return ret;
120 }
121 
122 static int alpha_noop_supported(struct device *dev, u64 mask)
123 {
124 	return mask < 0x00ffffffUL ? 0 : 1;
125 }
126 
127 const struct dma_map_ops alpha_noop_ops = {
128 	.alloc			= alpha_noop_alloc_coherent,
129 	.free			= dma_noop_free_coherent,
130 	.map_page		= dma_noop_map_page,
131 	.map_sg			= dma_noop_map_sg,
132 	.mapping_error		= dma_noop_mapping_error,
133 	.dma_supported		= alpha_noop_supported,
134 };
135 
136 const struct dma_map_ops *dma_ops = &alpha_noop_ops;
137 EXPORT_SYMBOL(dma_ops);
138