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/slab.h>
26 #include <linux/io.h>
27 
28 #include <asm/ppc-pci.h>
29 #include <asm/pci-bridge.h>
30 
31 #include "io-workarounds.h"
32 
33 #define SPIDER_PCI_DISABLE_PREFETCH
34 
35 struct spiderpci_iowa_private {
36 	void __iomem *regs;
37 };
38 
39 static void spiderpci_io_flush(struct iowa_bus *bus)
40 {
41 	struct spiderpci_iowa_private *priv;
42 	u32 val;
43 
44 	priv = bus->private;
45 	val = in_be32(priv->regs + SPIDER_PCI_DUMMY_READ);
46 	iosync();
47 }
48 
49 #define SPIDER_PCI_MMIO_READ(name, ret)					\
50 static ret spiderpci_##name(const PCI_IO_ADDR addr)			\
51 {									\
52 	ret val = __do_##name(addr);					\
53 	spiderpci_io_flush(iowa_mem_find_bus(addr));			\
54 	return val;							\
55 }
56 
57 #define SPIDER_PCI_MMIO_READ_STR(name)					\
58 static void spiderpci_##name(const PCI_IO_ADDR addr, void *buf, 	\
59 			     unsigned long count)			\
60 {									\
61 	__do_##name(addr, buf, count);					\
62 	spiderpci_io_flush(iowa_mem_find_bus(addr));			\
63 }
64 
65 SPIDER_PCI_MMIO_READ(readb, u8)
66 SPIDER_PCI_MMIO_READ(readw, u16)
67 SPIDER_PCI_MMIO_READ(readl, u32)
68 SPIDER_PCI_MMIO_READ(readq, u64)
69 SPIDER_PCI_MMIO_READ(readw_be, u16)
70 SPIDER_PCI_MMIO_READ(readl_be, u32)
71 SPIDER_PCI_MMIO_READ(readq_be, u64)
72 SPIDER_PCI_MMIO_READ_STR(readsb)
73 SPIDER_PCI_MMIO_READ_STR(readsw)
74 SPIDER_PCI_MMIO_READ_STR(readsl)
75 
76 static void spiderpci_memcpy_fromio(void *dest, const PCI_IO_ADDR src,
77 				    unsigned long n)
78 {
79 	__do_memcpy_fromio(dest, src, n);
80 	spiderpci_io_flush(iowa_mem_find_bus(src));
81 }
82 
83 static int __init spiderpci_pci_setup_chip(struct pci_controller *phb,
84 					   void __iomem *regs)
85 {
86 	void *dummy_page_va;
87 	dma_addr_t dummy_page_da;
88 
89 #ifdef SPIDER_PCI_DISABLE_PREFETCH
90 	u32 val = in_be32(regs + SPIDER_PCI_VCI_CNTL_STAT);
91 	pr_debug("SPIDER_IOWA:PVCI_Control_Status was 0x%08x\n", val);
92 	out_be32(regs + SPIDER_PCI_VCI_CNTL_STAT, val | 0x8);
93 #endif /* SPIDER_PCI_DISABLE_PREFETCH */
94 
95 	/* setup dummy read */
96 	/*
97 	 * On CellBlade, we can't know that which XDR memory is used by
98 	 * kmalloc() to allocate dummy_page_va.
99 	 * In order to imporve the performance, the XDR which is used to
100 	 * allocate dummy_page_va is the nearest the spider-pci.
101 	 * We have to select the CBE which is the nearest the spider-pci
102 	 * to allocate memory from the best XDR, but I don't know that
103 	 * how to do.
104 	 *
105 	 * Celleb does not have this problem, because it has only one XDR.
106 	 */
107 	dummy_page_va = kmalloc(PAGE_SIZE, GFP_KERNEL);
108 	if (!dummy_page_va) {
109 		pr_err("SPIDERPCI-IOWA:Alloc dummy_page_va failed.\n");
110 		return -1;
111 	}
112 
113 	dummy_page_da = dma_map_single(phb->parent, dummy_page_va,
114 				       PAGE_SIZE, DMA_FROM_DEVICE);
115 	if (dma_mapping_error(phb->parent, dummy_page_da)) {
116 		pr_err("SPIDER-IOWA:Map dummy page filed.\n");
117 		kfree(dummy_page_va);
118 		return -1;
119 	}
120 
121 	out_be32(regs + SPIDER_PCI_DUMMY_READ_BASE, dummy_page_da);
122 
123 	return 0;
124 }
125 
126 int __init spiderpci_iowa_init(struct iowa_bus *bus, void *data)
127 {
128 	void __iomem *regs = NULL;
129 	struct spiderpci_iowa_private *priv;
130 	struct device_node *np = bus->phb->dn;
131 	struct resource r;
132 	unsigned long offset = (unsigned long)data;
133 
134 	pr_debug("SPIDERPCI-IOWA:Bus initialize for spider(%s)\n",
135 		 np->full_name);
136 
137 	priv = kzalloc(sizeof(struct spiderpci_iowa_private), GFP_KERNEL);
138 	if (!priv) {
139 		pr_err("SPIDERPCI-IOWA:"
140 		       "Can't allocate struct spiderpci_iowa_private");
141 		return -1;
142 	}
143 
144 	if (of_address_to_resource(np, 0, &r)) {
145 		pr_err("SPIDERPCI-IOWA:Can't get resource.\n");
146 		goto error;
147 	}
148 
149 	regs = ioremap(r.start + offset, SPIDER_PCI_REG_SIZE);
150 	if (!regs) {
151 		pr_err("SPIDERPCI-IOWA:ioremap failed.\n");
152 		goto error;
153 	}
154 	priv->regs = regs;
155 	bus->private = priv;
156 
157 	if (spiderpci_pci_setup_chip(bus->phb, regs))
158 		goto error;
159 
160 	return 0;
161 
162 error:
163 	kfree(priv);
164 	bus->private = NULL;
165 
166 	if (regs)
167 		iounmap(regs);
168 
169 	return -1;
170 }
171 
172 struct ppc_pci_io spiderpci_ops = {
173 	.readb = spiderpci_readb,
174 	.readw = spiderpci_readw,
175 	.readl = spiderpci_readl,
176 	.readq = spiderpci_readq,
177 	.readw_be = spiderpci_readw_be,
178 	.readl_be = spiderpci_readl_be,
179 	.readq_be = spiderpci_readq_be,
180 	.readsb = spiderpci_readsb,
181 	.readsw = spiderpci_readsw,
182 	.readsl = spiderpci_readsl,
183 	.memcpy_fromio = spiderpci_memcpy_fromio,
184 };
185 
186