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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/mm.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#include <asm/pte-walk.h>
23
24
25#define IOWA_MAX_BUS 8
26
27static struct iowa_bus iowa_busses[IOWA_MAX_BUS];
28static unsigned int iowa_bus_count;
29
30static struct iowa_bus *iowa_pci_find(unsigned long vaddr, unsigned long paddr)
31{
32 int i, j;
33 struct resource *res;
34 unsigned long vstart, vend;
35
36 for (i = 0; i < iowa_bus_count; i++) {
37 struct iowa_bus *bus = &iowa_busses[i];
38 struct pci_controller *phb = bus->phb;
39
40 if (vaddr) {
41 vstart = (unsigned long)phb->io_base_virt;
42 vend = vstart + phb->pci_io_size - 1;
43 if ((vaddr >= vstart) && (vaddr <= vend))
44 return bus;
45 }
46
47 if (paddr)
48 for (j = 0; j < 3; j++) {
49 res = &phb->mem_resources[j];
50 if (paddr >= res->start && paddr <= res->end)
51 return bus;
52 }
53 }
54
55 return NULL;
56}
57
58#ifdef CONFIG_PPC_INDIRECT_MMIO
59struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
60{
61 unsigned hugepage_shift;
62 struct iowa_bus *bus;
63 int token;
64
65 token = PCI_GET_ADDR_TOKEN(addr);
66
67 if (token && token <= iowa_bus_count)
68 bus = &iowa_busses[token - 1];
69 else {
70 unsigned long vaddr, paddr;
71 pte_t *ptep;
72
73 vaddr = (unsigned long)PCI_FIX_ADDR(addr);
74 if (vaddr < PHB_IO_BASE || vaddr >= PHB_IO_END)
75 return NULL;
76 /*
77 * We won't find huge pages here (iomem). Also can't hit
78 * a page table free due to init_mm
79 */
80 ptep = find_init_mm_pte(vaddr, &hugepage_shift);
81 if (ptep == NULL)
82 paddr = 0;
83 else {
84 WARN_ON(hugepage_shift);
85 paddr = pte_pfn(*ptep) << PAGE_SHIFT;
86 }
87 bus = iowa_pci_find(vaddr, paddr);
88
89 if (bus == NULL)
90 return NULL;
91 }
92
93 return bus;
94}
95#else /* CONFIG_PPC_INDIRECT_MMIO */
96struct iowa_bus *iowa_mem_find_bus(const PCI_IO_ADDR addr)
97{
98 return NULL;
99}
100#endif /* !CONFIG_PPC_INDIRECT_MMIO */
101
102#ifdef CONFIG_PPC_INDIRECT_PIO
103struct iowa_bus *iowa_pio_find_bus(unsigned long port)
104{
105 unsigned long vaddr = (unsigned long)pci_io_base + port;
106 return iowa_pci_find(vaddr, 0);
107}
108#else
109struct iowa_bus *iowa_pio_find_bus(unsigned long port)
110{
111 return NULL;
112}
113#endif
114
115#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) \
116static ret iowa_##name at \
117{ \
118 struct iowa_bus *bus; \
119 bus = iowa_##space##_find_bus(aa); \
120 if (bus && bus->ops && bus->ops->name) \
121 return bus->ops->name al; \
122 return __do_##name al; \
123}
124
125#define DEF_PCI_AC_NORET(name, at, al, space, aa) \
126static void iowa_##name at \
127{ \
128 struct iowa_bus *bus; \
129 bus = iowa_##space##_find_bus(aa); \
130 if (bus && bus->ops && bus->ops->name) { \
131 bus->ops->name al; \
132 return; \
133 } \
134 __do_##name al; \
135}
136
137#include <asm/io-defs.h>
138
139#undef DEF_PCI_AC_RET
140#undef DEF_PCI_AC_NORET
141
142static const struct ppc_pci_io iowa_pci_io = {
143
144#define DEF_PCI_AC_RET(name, ret, at, al, space, aa) .name = iowa_##name,
145#define DEF_PCI_AC_NORET(name, at, al, space, aa) .name = iowa_##name,
146
147#include <asm/io-defs.h>
148
149#undef DEF_PCI_AC_RET
150#undef DEF_PCI_AC_NORET
151
152};
153
154#ifdef CONFIG_PPC_INDIRECT_MMIO
155static void __iomem *iowa_ioremap(phys_addr_t addr, unsigned long size,
156 unsigned long flags, void *caller)
157{
158 struct iowa_bus *bus;
159 void __iomem *res = __ioremap_caller(addr, size, flags, caller);
160 int busno;
161
162 bus = iowa_pci_find(0, (unsigned long)addr);
163 if (bus != NULL) {
164 busno = bus - iowa_busses;
165 PCI_SET_ADDR_TOKEN(res, busno + 1);
166 }
167 return res;
168}
169#else /* CONFIG_PPC_INDIRECT_MMIO */
170#define iowa_ioremap NULL
171#endif /* !CONFIG_PPC_INDIRECT_MMIO */
172
173/* Enable IO workaround */
174static void io_workaround_init(void)
175{
176 static int io_workaround_inited;
177
178 if (io_workaround_inited)
179 return;
180 ppc_pci_io = iowa_pci_io;
181 ppc_md.ioremap = iowa_ioremap;
182 io_workaround_inited = 1;
183}
184
185/* Register new bus to support workaround */
186void iowa_register_bus(struct pci_controller *phb, struct ppc_pci_io *ops,
187 int (*initfunc)(struct iowa_bus *, void *), void *data)
188{
189 struct iowa_bus *bus;
190 struct device_node *np = phb->dn;
191
192 io_workaround_init();
193
194 if (iowa_bus_count >= IOWA_MAX_BUS) {
195 pr_err("IOWA:Too many pci bridges, "
196 "workarounds disabled for %pOF\n", np);
197 return;
198 }
199
200 bus = &iowa_busses[iowa_bus_count];
201 bus->phb = phb;
202 bus->ops = ops;
203 bus->private = data;
204
205 if (initfunc)
206 if ((*initfunc)(bus, data))
207 return;
208
209 iowa_bus_count++;
210
211 pr_debug("IOWA:[%d]Add bus, %pOF.\n", iowa_bus_count-1, np);
212}
213