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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Support PCI IO workaround
4 *
5 * Copyright (C) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>
6 * IBM, Corp.
7 * (C) Copyright 2007-2008 TOSHIBA CORPORATION
8 */
9#undef DEBUG
10
11#include <linux/kernel.h>
12#include <linux/sched/mm.h> /* for init_mm */
13#include <linux/pgtable.h>
14
15#include <asm/io.h>
16#include <asm/machdep.h>
17#include <asm/ppc-pci.h>
18#include <asm/io-workarounds.h>
19#include <asm/pte-walk.h>
20
21
22#define IOWA_MAX_BUS 8
23
24static struct iowa_bus iowa_busses[IOWA_MAX_BUS];
25static unsigned int iowa_bus_count;
26
27static struct iowa_bus *iowa_pci_find(unsigned long vaddr, unsigned long paddr)
28{
29 int i, j;
30 struct resource *res;
31 unsigned long vstart, vend;
32
33 for (i = 0; i < iowa_bus_count; i++) {
34 struct iowa_bus *bus = &iowa_busses[i];
35 struct pci_controller *phb = bus->phb;
36
37 if (vaddr) {
38 vstart = (unsigned long)phb->io_base_virt;
39 vend = vstart + phb->pci_io_size - 1;
40 if ((vaddr >= vstart) && (vaddr <= vend))
41 return bus;
42 }
43
44 if (paddr)
45 for (j = 0; j < 3; j++) {
46 res = &phb->mem_resources[j];
47 if (paddr >= res->start && paddr <= res->end)
48 return bus;
49 }
50 }
51
52 return NULL;
53}
54
55#ifdef CONFIG_PPC_INDIRECT_MMIO
56struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
57{
58 unsigned hugepage_shift;
59 struct iowa_bus *bus;
60 int token;
61
62 token = PCI_GET_ADDR_TOKEN(addr);
63
64 if (token && token <= iowa_bus_count)
65 bus = &iowa_busses[token - 1];
66 else {
67 unsigned long vaddr, paddr;
68 pte_t *ptep;
69
70 vaddr = (unsigned long)PCI_FIX_ADDR(addr);
71 if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END)
72 return NULL;
73 /*
74 * We won't find huge pages here (iomem). Also can't hit
75 * a page table free due to init_mm
76 */
77 ptep = find_init_mm_pte(vaddr, &hugepage_shift);
78 if (ptep == NULL)
79 paddr = 0;
80 else {
81 WARN_ON(hugepage_shift);
82 paddr = pte_pfn(*ptep) << PAGE_SHIFT;
83 }
84 bus = iowa_pci_find(vaddr, paddr);
85
86 if (bus == NULL)
87 return NULL;
88 }
89
90 return bus;
91}
92#else /* CONFIG_PPC_INDIRECT_MMIO */
93struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
94{
95 return NULL;
96}
97#endif /* !CONFIG_PPC_INDIRECT_MMIO */
98
99#ifdef CONFIG_PPC_INDIRECT_PIO
100struct iowa_bus *iowa_pio_find_bus(unsigned long port)
101{
102 unsigned long vaddr = (unsigned long)pci_io_base + port;
103 return iowa_pci_find(vaddr, 0);
104}
105#else
106struct iowa_bus *iowa_pio_find_bus(unsigned long port)
107{
108 return NULL;
109}
110#endif
111
112#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \
113static ret iowa_##name at \
114{ \
115 struct iowa_bus *bus; \
116 bus = iowa_##space##_find_bus(aa); \
117 if (bus && bus->ops && bus->ops->name) \
118 return bus->ops->name al; \
119 return __do_##name al; \
120}
121
122#define DEF_PCI_AC_NORET(name, at, al, space, aa) \
123static void iowa_##name at \
124{ \
125 struct iowa_bus *bus; \
126 bus = iowa_##space##_find_bus(aa); \
127 if (bus && bus->ops && bus->ops->name) { \
128 bus->ops->name al; \
129 return; \
130 } \
131 __do_##name al; \
132}
133
134#include <asm/io-defs.h>
135
136#undef DEF_PCI_AC_RET
137#undef DEF_PCI_AC_NORET
138
139static const struct ppc_pci_io iowa_pci_io = {
140
141#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name,
142#define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name,
143
144#include <asm/io-defs.h>
145
146#undef DEF_PCI_AC_RET
147#undef DEF_PCI_AC_NORET
148
149};
150
151#ifdef CONFIG_PPC_INDIRECT_MMIO
152void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size,
153 pgprot_t prot, void *caller)
154{
155 struct iowa_bus *bus;
156 void __iomem *res = __ioremap_caller(addr, size, prot, caller);
157 int busno;
158
159 bus = iowa_pci_find(0, (unsigned long)addr);
160 if (bus != NULL) {
161 busno = bus - iowa_busses;
162 PCI_SET_ADDR_TOKEN(res, busno + 1);
163 }
164 return res;
165}
166#endif /* !CONFIG_PPC_INDIRECT_MMIO */
167
168bool io_workaround_inited;
169
170/* Enable IO workaround */
171static void io_workaround_init(void)
172{
173 if (io_workaround_inited)
174 return;
175 ppc_pci_io = iowa_pci_io;
176 io_workaround_inited = true;
177}
178
179/* Register new bus to support workaround */
180void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops,
181 int (*initfunc)(struct iowa_bus *, void *), void *data)
182{
183 struct iowa_bus *bus;
184 struct device_node *np = phb->dn;
185
186 io_workaround_init();
187
188 if (iowa_bus_count >= IOWA_MAX_BUS) {
189 pr_err("IOWA:Too many pci bridges, "
190 "workarounds disabled for %pOF\n", np);
191 return;
192 }
193
194 bus = &iowa_busses[iowa_bus_count];
195 bus->phb = phb;
196 bus->ops = ops;
197 bus->private = data;
198
199 if (initfunc)
200 if ((*initfunc)(bus, data))
201 return;
202
203 iowa_bus_count++;
204
205 pr_debug("IOWA:[%d]Add bus, %pOF.\n", iowa_bus_count-1, np);
206}
207
1/*
2 * Support PCI IO workaround
3 *
4 * Copyright (C) 2006 Benjamin Herrenschmidt <benh@kernel.crashing.org>
5 * IBM, Corp.
6 * (C) Copyright 2007-2008 TOSHIBA CORPORATION
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12#undef DEBUG
13
14#include <linux/kernel.h>
15#include <linux/sched.h> /* for init_mm */
16
17#include <asm/io.h>
18#include <asm/machdep.h>
19#include <asm/pgtable.h>
20#include <asm/ppc-pci.h>
21#include <asm/io-workarounds.h>
22
23#define IOWA_MAX_BUS 8
24
25static struct iowa_bus iowa_busses[IOWA_MAX_BUS];
26static unsigned int iowa_bus_count;
27
28static struct iowa_bus *iowa_pci_find(unsigned long vaddr, unsigned long paddr)
29{
30 int i, j;
31 struct resource *res;
32 unsigned long vstart, vend;
33
34 for (i = 0; i < iowa_bus_count; i++) {
35 struct iowa_bus *bus = &iowa_busses[i];
36 struct pci_controller *phb = bus->phb;
37
38 if (vaddr) {
39 vstart = (unsigned long)phb->io_base_virt;
40 vend = vstart + phb->pci_io_size - 1;
41 if ((vaddr >= vstart) && (vaddr <= vend))
42 return bus;
43 }
44
45 if (paddr)
46 for (j = 0; j < 3; j++) {
47 res = &phb->mem_resources[j];
48 if (paddr >= res->start && paddr <= res->end)
49 return bus;
50 }
51 }
52
53 return NULL;
54}
55
56#ifdef CONFIG_PPC_INDIRECT_MMIO
57struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
58{
59 unsigned hugepage_shift;
60 struct iowa_bus *bus;
61 int token;
62
63 token = PCI_GET_ADDR_TOKEN(addr);
64
65 if (token && token <= iowa_bus_count)
66 bus = &iowa_busses[token - 1];
67 else {
68 unsigned long vaddr, paddr;
69 pte_t *ptep;
70
71 vaddr = (unsigned long)PCI_FIX_ADDR(addr);
72 if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END)
73 return NULL;
74
75 ptep = find_linux_pte_or_hugepte(init_mm.pgd, vaddr,
76 &hugepage_shift);
77 if (ptep == NULL)
78 paddr = 0;
79 else {
80 /*
81 * we don't have hugepages backing iomem
82 */
83 WARN_ON(hugepage_shift);
84 paddr = pte_pfn(*ptep) << PAGE_SHIFT;
85 }
86 bus = iowa_pci_find(vaddr, paddr);
87
88 if (bus == NULL)
89 return NULL;
90 }
91
92 return bus;
93}
94#else /* CONFIG_PPC_INDIRECT_MMIO */
95struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
96{
97 return NULL;
98}
99#endif /* !CONFIG_PPC_INDIRECT_MMIO */
100
101#ifdef CONFIG_PPC_INDIRECT_PIO
102struct iowa_bus *iowa_pio_find_bus(unsigned long port)
103{
104 unsigned long vaddr = (unsigned long)pci_io_base + port;
105 return iowa_pci_find(vaddr, 0);
106}
107#else
108struct iowa_bus *iowa_pio_find_bus(unsigned long port)
109{
110 return NULL;
111}
112#endif
113
114#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \
115static ret iowa_##name at \
116{ \
117 struct iowa_bus *bus; \
118 bus = iowa_##space##_find_bus(aa); \
119 if (bus && bus->ops && bus->ops->name) \
120 return bus->ops->name al; \
121 return __do_##name al; \
122}
123
124#define DEF_PCI_AC_NORET(name, at, al, space, aa) \
125static void iowa_##name at \
126{ \
127 struct iowa_bus *bus; \
128 bus = iowa_##space##_find_bus(aa); \
129 if (bus && bus->ops && bus->ops->name) { \
130 bus->ops->name al; \
131 return; \
132 } \
133 __do_##name al; \
134}
135
136#include <asm/io-defs.h>
137
138#undef DEF_PCI_AC_RET
139#undef DEF_PCI_AC_NORET
140
141static const struct ppc_pci_io iowa_pci_io = {
142
143#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name,
144#define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name,
145
146#include <asm/io-defs.h>
147
148#undef DEF_PCI_AC_RET
149#undef DEF_PCI_AC_NORET
150
151};
152
153#ifdef CONFIG_PPC_INDIRECT_MMIO
154static void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size,
155 unsigned long flags, void *caller)
156{
157 struct iowa_bus *bus;
158 void __iomem *res = __ioremap_caller(addr, size, flags, caller);
159 int busno;
160
161 bus = iowa_pci_find(0, (unsigned long)addr);
162 if (bus != NULL) {
163 busno = bus - iowa_busses;
164 PCI_SET_ADDR_TOKEN(res, busno + 1);
165 }
166 return res;
167}
168#else /* CONFIG_PPC_INDIRECT_MMIO */
169#define iowa_ioremap NULL
170#endif /* !CONFIG_PPC_INDIRECT_MMIO */
171
172/* Enable IO workaround */
173static void io_workaround_init(void)
174{
175 static int io_workaround_inited;
176
177 if (io_workaround_inited)
178 return;
179 ppc_pci_io = iowa_pci_io;
180 ppc_md.ioremap = iowa_ioremap;
181 io_workaround_inited = 1;
182}
183
184/* Register new bus to support workaround */
185void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops,
186 int (*initfunc)(struct iowa_bus *, void *), void *data)
187{
188 struct iowa_bus *bus;
189 struct device_node *np = phb->dn;
190
191 io_workaround_init();
192
193 if (iowa_bus_count >= IOWA_MAX_BUS) {
194 pr_err("IOWA:Too many pci bridges, "
195 "workarounds disabled for %s\n", np->full_name);
196 return;
197 }
198
199 bus = &iowa_busses[iowa_bus_count];
200 bus->phb = phb;
201 bus->ops = ops;
202 bus->private = data;
203
204 if (initfunc)
205 if ((*initfunc)(bus, data))
206 return;
207
208 iowa_bus_count++;
209
210 pr_debug("IOWA:[%d]Add bus, %s.\n", iowa_bus_count-1, np->full_name);
211}
212