1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * IO workarounds for PCI on Celleb/Cell platform
4 *
5 * (C) Copyright 2006-2007 TOSHIBA CORPORATION
6 */
7
8 #undef DEBUG
9
10 #include <linux/kernel.h>
11 #include <linux/of_address.h>
12 #include <linux/of_platform.h>
13 #include <linux/slab.h>
14 #include <linux/io.h>
15
16 #include <asm/ppc-pci.h>
17 #include <asm/pci-bridge.h>
18 #include <asm/io-workarounds.h>
19
20 #define SPIDER_PCI_DISABLE_PREFETCH
21
22 struct spiderpci_iowa_private {
23 void __iomem *regs;
24 };
25
spiderpci_io_flush(struct iowa_bus * bus)26 static void spiderpci_io_flush(struct iowa_bus *bus)
27 {
28 struct spiderpci_iowa_private *priv;
29
30 priv = bus->private;
31 in_be32(priv->regs + SPIDER_PCI_DUMMY_READ);
32 iosync();
33 }
34
35 #define SPIDER_PCI_MMIO_READ(name, ret) \
36 static ret spiderpci_##name(const PCI_IO_ADDR addr) \
37 { \
38 ret val = __do_##name(addr); \
39 spiderpci_io_flush(iowa_mem_find_bus(addr)); \
40 return val; \
41 }
42
43 #define SPIDER_PCI_MMIO_READ_STR(name) \
44 static void spiderpci_##name(const PCI_IO_ADDR addr, void *buf, \
45 unsigned long count) \
46 { \
47 __do_##name(addr, buf, count); \
48 spiderpci_io_flush(iowa_mem_find_bus(addr)); \
49 }
50
SPIDER_PCI_MMIO_READ(readb,u8)51 SPIDER_PCI_MMIO_READ(readb, u8)
52 SPIDER_PCI_MMIO_READ(readw, u16)
53 SPIDER_PCI_MMIO_READ(readl, u32)
54 SPIDER_PCI_MMIO_READ(readq, u64)
55 SPIDER_PCI_MMIO_READ(readw_be, u16)
56 SPIDER_PCI_MMIO_READ(readl_be, u32)
57 SPIDER_PCI_MMIO_READ(readq_be, u64)
58 SPIDER_PCI_MMIO_READ_STR(readsb)
59 SPIDER_PCI_MMIO_READ_STR(readsw)
60 SPIDER_PCI_MMIO_READ_STR(readsl)
61
62 static void spiderpci_memcpy_fromio(void *dest, const PCI_IO_ADDR src,
63 unsigned long n)
64 {
65 __do_memcpy_fromio(dest, src, n);
66 spiderpci_io_flush(iowa_mem_find_bus(src));
67 }
68
spiderpci_pci_setup_chip(struct pci_controller * phb,void __iomem * regs)69 static int __init spiderpci_pci_setup_chip(struct pci_controller *phb,
70 void __iomem *regs)
71 {
72 void *dummy_page_va;
73 dma_addr_t dummy_page_da;
74
75 #ifdef SPIDER_PCI_DISABLE_PREFETCH
76 u32 val = in_be32(regs + SPIDER_PCI_VCI_CNTL_STAT);
77 pr_debug("SPIDER_IOWA:PVCI_Control_Status was 0x%08x\n", val);
78 out_be32(regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8);
79 #endif /* SPIDER_PCI_DISABLE_PREFETCH */
80
81 /* setup dummy read */
82 /*
83 * On CellBlade, we can't know that which XDR memory is used by
84 * kmalloc() to allocate dummy_page_va.
85 * In order to improve the performance, the XDR which is used to
86 * allocate dummy_page_va is the nearest the spider-pci.
87 * We have to select the CBE which is the nearest the spider-pci
88 * to allocate memory from the best XDR, but I don't know that
89 * how to do.
90 *
91 * Celleb does not have this problem, because it has only one XDR.
92 */
93 dummy_page_va = kmalloc(PAGE_SIZE, GFP_KERNEL);
94 if (!dummy_page_va) {
95 pr_err("SPIDERPCI-IOWA:Alloc dummy_page_va failed.\n");
96 return -1;
97 }
98
99 dummy_page_da = dma_map_single(phb->parent, dummy_page_va,
100 PAGE_SIZE, DMA_FROM_DEVICE);
101 if (dma_mapping_error(phb->parent, dummy_page_da)) {
102 pr_err("SPIDER-IOWA:Map dummy page filed.\n");
103 kfree(dummy_page_va);
104 return -1;
105 }
106
107 out_be32(regs + SPIDER_PCI_DUMMY_READ_BASE, dummy_page_da);
108
109 return 0;
110 }
111
spiderpci_iowa_init(struct iowa_bus * bus,void * data)112 int __init spiderpci_iowa_init(struct iowa_bus *bus, void *data)
113 {
114 void __iomem *regs = NULL;
115 struct spiderpci_iowa_private *priv;
116 struct device_node *np = bus->phb->dn;
117 struct resource r;
118 unsigned long offset = (unsigned long)data;
119
120 pr_debug("SPIDERPCI-IOWA:Bus initialize for spider(%pOF)\n",
121 np);
122
123 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
124 if (!priv) {
125 pr_err("SPIDERPCI-IOWA:"
126 "Can't allocate struct spiderpci_iowa_private");
127 return -1;
128 }
129
130 if (of_address_to_resource(np, 0, &r)) {
131 pr_err("SPIDERPCI-IOWA:Can't get resource.\n");
132 goto error;
133 }
134
135 regs = ioremap(r.start + offset, SPIDER_PCI_REG_SIZE);
136 if (!regs) {
137 pr_err("SPIDERPCI-IOWA:ioremap failed.\n");
138 goto error;
139 }
140 priv->regs = regs;
141 bus->private = priv;
142
143 if (spiderpci_pci_setup_chip(bus->phb, regs))
144 goto error;
145
146 return 0;
147
148 error:
149 kfree(priv);
150 bus->private = NULL;
151
152 if (regs)
153 iounmap(regs);
154
155 return -1;
156 }
157
158 struct ppc_pci_io spiderpci_ops = {
159 .readb = spiderpci_readb,
160 .readw = spiderpci_readw,
161 .readl = spiderpci_readl,
162 .readq = spiderpci_readq,
163 .readw_be = spiderpci_readw_be,
164 .readl_be = spiderpci_readl_be,
165 .readq_be = spiderpci_readq_be,
166 .readsb = spiderpci_readsb,
167 .readsw = spiderpci_readsw,
168 .readsl = spiderpci_readsl,
169 .memcpy_fromio = spiderpci_memcpy_fromio,
170 };
171
172