summaryrefslogtreecommitdiffstats
path: root/arch/sh/drivers/pci/pci-sh7751.c
blob: 1b9e5caac389838b995b1d17deb55b6314f3de13 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
// SPDX-License-Identifier: GPL-2.0
/*
 * Low-Level PCI Support for the SH7751
 *
 *  Copyright (C) 2003 - 2009  Paul Mundt
 *  Copyright (C) 2001  Dustin McIntire
 *
 *  With cleanup by Paul van Gool <pvangool@mimotech.com>, 2003.
 */
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/io.h>
#include "pci-sh4.h"
#include <asm/addrspace.h>
#include <asm/sizes.h>

static int __init __area_sdram_check(struct pci_channel *chan,
				     unsigned int area)
{
	unsigned long word;

	word = __raw_readl(SH7751_BCR1);
	/* check BCR for SDRAM in area */
	if (((word >> area) & 1) == 0) {
		printk("PCI: Area %d is not configured for SDRAM. BCR1=0x%lx\n",
		       area, word);
		return 0;
	}
	pci_write_reg(chan, word, SH4_PCIBCR1);

	word = __raw_readw(SH7751_BCR2);
	/* check BCR2 for 32bit SDRAM interface*/
	if (((word >> (area << 1)) & 0x3) != 0x3) {
		printk("PCI: Area %d is not 32 bit SDRAM. BCR2=0x%lx\n",
		       area, word);
		return 0;
	}
	pci_write_reg(chan, word, SH4_PCIBCR2);

	return 1;
}

static struct resource sh7751_pci_resources[] = {
	{
		.name	= "SH7751_IO",
		.start	= 0x1000,
		.end	= SZ_4M - 1,
		.flags	= IORESOURCE_IO
	}, {
		.name	= "SH7751_mem",
		.start	= SH7751_PCI_MEMORY_BASE,
		.end	= SH7751_PCI_MEMORY_BASE + SH7751_PCI_MEM_SIZE - 1,
		.flags	= IORESOURCE_MEM
	},
};

static struct pci_channel sh7751_pci_controller = {
	.pci_ops	= &sh4_pci_ops,
	.resources	= sh7751_pci_resources,
	.nr_resources	= ARRAY_SIZE(sh7751_pci_resources),
	.mem_offset	= 0x00000000,
	.io_offset	= 0x00000000,
	.io_map_base	= SH7751_PCI_IO_BASE,
};

static struct sh4_pci_address_map sh7751_pci_map = {
	.window0	= {
		.base	= SH7751_CS3_BASE_ADDR,
		.size	= 0x04000000,
	},
};

static int __init sh7751_pci_init(void)
{
	struct pci_channel *chan = &sh7751_pci_controller;
	unsigned int id;
	u32 word, reg;

	printk(KERN_NOTICE "PCI: Starting initialization.\n");

	chan->reg_base = 0xfe200000;

	/* check for SH7751/SH7751R hardware */
	id = pci_read_reg(chan, SH7751_PCICONF0);
	if (id != ((SH7751_DEVICE_ID << 16) | SH7751_VENDOR_ID) &&
	    id != ((SH7751R_DEVICE_ID << 16) | SH7751_VENDOR_ID)) {
		pr_debug("PCI: This is not an SH7751(R) (%x)\n", id);
		return -ENODEV;
	}

	/* Set the BCR's to enable PCI access */
	reg = __raw_readl(SH7751_BCR1);
	reg |= 0x80000;
	__raw_writel(reg, SH7751_BCR1);

	/* Turn the clocks back on (not done in reset)*/
	pci_write_reg(chan, 0, SH4_PCICLKR);
	/* Clear Powerdown IRQ's (not done in reset) */
	word = SH4_PCIPINT_D3 | SH4_PCIPINT_D0;
	pci_write_reg(chan, word, SH4_PCIPINT);

	/* set the command/status bits to:
	 * Wait Cycle Control + Parity Enable + Bus Master +
	 * Mem space enable
	 */
	word = SH7751_PCICONF1_WCC | SH7751_PCICONF1_PER |
	       SH7751_PCICONF1_BUM | SH7751_PCICONF1_MES;
	pci_write_reg(chan, word, SH7751_PCICONF1);

	/* define this host as the host bridge */
	word = PCI_BASE_CLASS_BRIDGE << 24;
	pci_write_reg(chan, word, SH7751_PCICONF2);

	/* Set IO and Mem windows to local address
	 * Make PCI and local address the same for easy 1 to 1 mapping
	 */
	word = sh7751_pci_map.window0.size - 1;
	pci_write_reg(chan, word, SH4_PCILSR0);
	/* Set the values on window 0 PCI config registers */
	word = P2SEGADDR(sh7751_pci_map.window0.base);
	pci_write_reg(chan, word, SH4_PCILAR0);
	pci_write_reg(chan, word, SH7751_PCICONF5);

	/* Set the local 16MB PCI memory space window to
	 * the lowest PCI mapped address
	 */
	word = chan->resources[1].start & SH4_PCIMBR_MASK;
	pr_debug("PCI: Setting upper bits of Memory window to 0x%x\n", word);
	pci_write_reg(chan, word , SH4_PCIMBR);

	/* Make sure the MSB's of IO window are set to access PCI space
	 * correctly */
	word = chan->resources[0].start & SH4_PCIIOBR_MASK;
	pr_debug("PCI: Setting upper bits of IO window to 0x%x\n", word);
	pci_write_reg(chan, word, SH4_PCIIOBR);

	/* Set PCI WCRx, BCRx's, copy from BSC locations */

	/* check BCR for SDRAM in specified area */
	switch (sh7751_pci_map.window0.base) {
	case SH7751_CS0_BASE_ADDR: word = __area_sdram_check(chan, 0); break;
	case SH7751_CS1_BASE_ADDR: word = __area_sdram_check(chan, 1); break;
	case SH7751_CS2_BASE_ADDR: word = __area_sdram_check(chan, 2); break;
	case SH7751_CS3_BASE_ADDR: word = __area_sdram_check(chan, 3); break;
	case SH7751_CS4_BASE_ADDR: word = __area_sdram_check(chan, 4); break;
	case SH7751_CS5_BASE_ADDR: word = __area_sdram_check(chan, 5); break;
	case SH7751_CS6_BASE_ADDR: word = __area_sdram_check(chan, 6); break;
	}

	if (!word)
		return -1;

	/* configure the wait control registers */
	word = __raw_readl(SH7751_WCR1);
	pci_write_reg(chan, word, SH4_PCIWCR1);
	word = __raw_readl(SH7751_WCR2);
	pci_write_reg(chan, word, SH4_PCIWCR2);
	word = __raw_readl(SH7751_WCR3);
	pci_write_reg(chan, word, SH4_PCIWCR3);
	word = __raw_readl(SH7751_MCR);
	pci_write_reg(chan, word, SH4_PCIMCR);

	/* NOTE: I'm ignoring the PCI error IRQs for now..
	 * TODO: add support for the internal error interrupts and
	 * DMA interrupts...
	 */

	pci_fixup_pcic(chan);

	/* SH7751 init done, set central function init complete */
	/* use round robin mode to stop a device starving/overruning */
	word = SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_ARBM;
	pci_write_reg(chan, word, SH4_PCICR);

	return register_pci_controller(chan);
}
arch_initcall(sh7751_pci_init);