Merge branch 'linus' into x86/x2apic
[linux-2.6] / arch / powerpc / platforms / cell / spider-pci.c
1 /*
2  * IO workarounds for PCI on Celleb/Cell platform
3  *
4  * (C) Copyright 2006-2007 TOSHIBA CORPORATION
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20
21 #undef DEBUG
22
23 #include <linux/kernel.h>
24 #include <linux/of_platform.h>
25 #include <linux/io.h>
26
27 #include <asm/ppc-pci.h>
28 #include <asm/pci-bridge.h>
29
30 #include "io-workarounds.h"
31
32 #define SPIDER_PCI_DISABLE_PREFETCH
33
34 struct spiderpci_iowa_private {
35         void __iomem *regs;
36 };
37
38 static void spiderpci_io_flush(struct iowa_bus *bus)
39 {
40         struct spiderpci_iowa_private *priv;
41         u32 val;
42
43         priv = bus->private;
44         val = in_be32(priv->regs + SPIDER_PCI_DUMMY_READ);
45         iosync();
46 }
47
48 #define SPIDER_PCI_MMIO_READ(name, ret)                                 \
49 static ret spiderpci_##name(const PCI_IO_ADDR addr)                     \
50 {                                                                       \
51         ret val = __do_##name(addr);                                    \
52         spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
53         return val;                                                     \
54 }
55
56 #define SPIDER_PCI_MMIO_READ_STR(name)                                  \
57 static void spiderpci_##name(const PCI_IO_ADDR addr, void *buf,         \
58                              unsigned long count)                       \
59 {                                                                       \
60         __do_##name(addr, buf, count);                                  \
61         spiderpci_io_flush(iowa_mem_find_bus(addr));                    \
62 }
63
64 SPIDER_PCI_MMIO_READ(readb, u8)
65 SPIDER_PCI_MMIO_READ(readw, u16)
66 SPIDER_PCI_MMIO_READ(readl, u32)
67 SPIDER_PCI_MMIO_READ(readq, u64)
68 SPIDER_PCI_MMIO_READ(readw_be, u16)
69 SPIDER_PCI_MMIO_READ(readl_be, u32)
70 SPIDER_PCI_MMIO_READ(readq_be, u64)
71 SPIDER_PCI_MMIO_READ_STR(readsb)
72 SPIDER_PCI_MMIO_READ_STR(readsw)
73 SPIDER_PCI_MMIO_READ_STR(readsl)
74
75 static void spiderpci_memcpy_fromio(void *dest, const PCI_IO_ADDR src,
76                                     unsigned long n)
77 {
78         __do_memcpy_fromio(dest, src, n);
79         spiderpci_io_flush(iowa_mem_find_bus(src));
80 }
81
82 static int __init spiderpci_pci_setup_chip(struct pci_controller *phb,
83                                            void __iomem *regs)
84 {
85         void *dummy_page_va;
86         dma_addr_t dummy_page_da;
87
88 #ifdef SPIDER_PCI_DISABLE_PREFETCH
89         u32 val = in_be32(regs + SPIDER_PCI_VCI_CNTL_STAT);
90         pr_debug("SPIDER_IOWA:PVCI_Control_Status was 0x%08x\n", val);
91         out_be32(regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8);
92 #endif /* SPIDER_PCI_DISABLE_PREFETCH */
93
94         /* setup dummy read */
95         /*
96          * On CellBlade, we can't know that which XDR memory is used by
97          * kmalloc() to allocate dummy_page_va.
98          * In order to imporve the performance, the XDR which is used to
99          * allocate dummy_page_va is the nearest the spider-pci.
100          * We have to select the CBE which is the nearest the spider-pci
101          * to allocate memory from the best XDR, but I don't know that
102          * how to do.
103          *
104          * Celleb does not have this problem, because it has only one XDR.
105          */
106         dummy_page_va = kmalloc(PAGE_SIZE, GFP_KERNEL);
107         if (!dummy_page_va) {
108                 pr_err("SPIDERPCI-IOWA:Alloc dummy_page_va failed.\n");
109                 return -1;
110         }
111
112         dummy_page_da = dma_map_single(phb->parent, dummy_page_va,
113                                        PAGE_SIZE, DMA_FROM_DEVICE);
114         if (dma_mapping_error(phb->parent, dummy_page_da)) {
115                 pr_err("SPIDER-IOWA:Map dummy page filed.\n");
116                 kfree(dummy_page_va);
117                 return -1;
118         }
119
120         out_be32(regs + SPIDER_PCI_DUMMY_READ_BASE, dummy_page_da);
121
122         return 0;
123 }
124
125 int __init spiderpci_iowa_init(struct iowa_bus *bus, void *data)
126 {
127         void __iomem *regs = NULL;
128         struct spiderpci_iowa_private *priv;
129         struct device_node *np = bus->phb->dn;
130         struct resource r;
131         unsigned long offset = (unsigned long)data;
132
133         pr_debug("SPIDERPCI-IOWA:Bus initialize for spider(%s)\n",
134                  np->full_name);
135
136         priv = kzalloc(sizeof(struct spiderpci_iowa_private), GFP_KERNEL);
137         if (!priv) {
138                 pr_err("SPIDERPCI-IOWA:"
139                        "Can't allocate struct spiderpci_iowa_private");
140                 return -1;
141         }
142
143         if (of_address_to_resource(np, 0, &r)) {
144                 pr_err("SPIDERPCI-IOWA:Can't get resource.\n");
145                 goto error;
146         }
147
148         regs = ioremap(r.start + offset, SPIDER_PCI_REG_SIZE);
149         if (!regs) {
150                 pr_err("SPIDERPCI-IOWA:ioremap failed.\n");
151                 goto error;
152         }
153         priv->regs = regs;
154         bus->private = priv;
155
156         if (spiderpci_pci_setup_chip(bus->phb, regs))
157                 goto error;
158
159         return 0;
160
161 error:
162         kfree(priv);
163         bus->private = NULL;
164
165         if (regs)
166                 iounmap(regs);
167
168         return -1;
169 }
170
171 struct ppc_pci_io spiderpci_ops = {
172         .readb = spiderpci_readb,
173         .readw = spiderpci_readw,
174         .readl = spiderpci_readl,
175         .readq = spiderpci_readq,
176         .readw_be = spiderpci_readw_be,
177         .readl_be = spiderpci_readl_be,
178         .readq_be = spiderpci_readq_be,
179         .readsb = spiderpci_readsb,
180         .readsw = spiderpci_readsw,
181         .readsl = spiderpci_readsl,
182         .memcpy_fromio = spiderpci_memcpy_fromio,
183 };
184