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/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
21struct spiderpci_iowa_private {
22	void __iomem *regs;
23};
24
25static 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)					\
35static 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)					\
43static 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
50SPIDER_PCI_MMIO_READ(readb, u8)
51SPIDER_PCI_MMIO_READ(readw, u16)
52SPIDER_PCI_MMIO_READ(readl, u32)
53SPIDER_PCI_MMIO_READ(readq, u64)
54SPIDER_PCI_MMIO_READ(readw_be, u16)
55SPIDER_PCI_MMIO_READ(readl_be, u32)
56SPIDER_PCI_MMIO_READ(readq_be, u64)
57SPIDER_PCI_MMIO_READ_STR(readsb)
58SPIDER_PCI_MMIO_READ_STR(readsw)
59SPIDER_PCI_MMIO_READ_STR(readsl)
60
61static 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
68static 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 improve 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
111int __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
147error:
148	kfree(priv);
149	bus->private = NULL;
150
151	if (regs)
152		iounmap(regs);
153
154	return -1;
155}
156
157struct 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