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