summaryrefslogtreecommitdiffstats
path: root/arch/sh/drivers/pci/pci-sh7751.c
blob: 9ddff760d3c6fdbf856e92b79fae6c6c2c36bc68 (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
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 *	Low-Level PCI Support for the SH7751
 *
 *  Dustin McIntire (dustin@sensoria.com)
 *	Derived from arch/i386/kernel/pci-*.c which bore the message:
 *	(c) 1999--2000 Martin Mares <mj@ucw.cz>
 *
 *  Ported to the new API by Paul Mundt <lethal@linux-sh.org>
 *  With cleanup by Paul van Gool <pvangool@mimotech.com>
 *
 *  May be copied or modified under the terms of the GNU General Public
 *  License.  See linux/COPYING for more information.
 *
 */

#undef DEBUG

#include <linux/init.h>
#include <linux/pci.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/delay.h>
#include "pci-sh4.h"
#include <asm/addrspace.h>
#include <asm/io.h>

/*
 * Initialization. Try all known PCI access methods. Note that we support
 * using both PCI BIOS and direct access: in such cases, we use I/O ports
 * to access config space.
 * 
 * Note that the platform specific initialization (BSC registers, and memory
 * space mapping) will be called via the platform defined function
 * pcibios_init_platform().
 */
static int __init sh7751_pci_init(void)
{
	unsigned int id;
	int ret;

	pr_debug("PCI: Starting intialization.\n");

	/* check for SH7751/SH7751R hardware */
	id = pci_read_reg(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;
	}

	if ((ret = sh4_pci_check_direct()) != 0)
		return ret;

	return pcibios_init_platform();
}
subsys_initcall(sh7751_pci_init);

static int __init __area_sdram_check(unsigned int area)
{
	u32 word;

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

	word = (u16)inw(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%x\n",
		       area, word);
		return 0;
	}
	pci_write_reg(word, SH4_PCIBCR2);

	return 1;
}

int __init sh7751_pcic_init(struct sh4_pci_address_map *map)
{
	u32 reg;
	u32 word;

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

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

	/*
	 * This code is unused for some boards as it is done in the
	 * bootloader and doing it here means the MAC addresses loaded
	 * by the bootloader get lost.
	 */
	if (!(map->flags & SH4_PCIC_NO_RESET)) {
		/* toggle PCI reset pin */
		word = SH4_PCICR_PREFIX | SH4_PCICR_PRST;
		pci_write_reg(word, SH4_PCICR);
		/* Wait for a long time... not 1 sec. but long enough */
		mdelay(100);
		word = SH4_PCICR_PREFIX;
		pci_write_reg(word, SH4_PCICR);
	}

	/* 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(word, SH7751_PCICONF1);

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

	/* Set IO and Mem windows to local address 
	 * Make PCI and local address the same for easy 1 to 1 mapping 
	 * Window0 = map->window0.size @ non-cached area base = SDRAM
	 * Window1 = map->window1.size @ cached area base = SDRAM 
	 */
	word = map->window0.size - 1;
	pci_write_reg(word, SH4_PCILSR0);
	word = map->window1.size - 1;
	pci_write_reg(word, SH4_PCILSR1);
	/* Set the values on window 0 PCI config registers */
	word = P2SEGADDR(map->window0.base);
	pci_write_reg(word, SH4_PCILAR0);
	pci_write_reg(word, SH7751_PCICONF5);
	/* Set the values on window 1 PCI config registers */
	word =  PHYSADDR(map->window1.base);
	pci_write_reg(word, SH4_PCILAR1);
	pci_write_reg(word, SH7751_PCICONF6);

	/* Set the local 16MB PCI memory space window to
	 * the lowest PCI mapped address
	 */
	word = PCIBIOS_MIN_MEM & SH4_PCIMBR_MASK;
	pr_debug("PCI: Setting upper bits of Memory window to 0x%x\n", word);
	pci_write_reg(word , SH4_PCIMBR);

	/* Map IO space into PCI IO window
	 * The IO window is 64K-PCIBIOS_MIN_IO in size
	 * IO addresses will be translated to the
	 * PCI IO window base address
	 */
	pr_debug("PCI: Mapping IO address 0x%x - 0x%x to base 0x%x\n",
		 PCIBIOS_MIN_IO, (64 << 10),
		 SH7751_PCI_IO_BASE + PCIBIOS_MIN_IO);

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

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

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

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

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

#ifdef CONFIG_SH_RTS7751R2D
	pci_fixup_pcic();
#endif

	/* 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(word, SH4_PCICR);

	return 1;
}