xref: /openbmc/linux/arch/sh/drivers/pci/pci-sh7780.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  *	Low-Level PCI Support for the SH7780
3  *
4  *  Dustin McIntire (dustin@sensoria.com)
5  *	Derived from arch/i386/kernel/pci-*.c which bore the message:
6  *	(c) 1999--2000 Martin Mares <mj@ucw.cz>
7  *
8  *  Ported to the new API by Paul Mundt <lethal@linux-sh.org>
9  *  With cleanup by Paul van Gool <pvangool@mimotech.com>
10  *
11  *  May be copied or modified under the terms of the GNU General Public
12  *  License.  See linux/COPYING for more information.
13  *
14  */
15 #undef DEBUG
16 
17 #include <linux/types.h>
18 #include <linux/kernel.h>
19 #include <linux/init.h>
20 #include <linux/pci.h>
21 #include <linux/errno.h>
22 #include <linux/delay.h>
23 #include "pci-sh4.h"
24 
25 #define INTC_BASE	0xffd00000
26 #define INTC_ICR0	(INTC_BASE+0x0)
27 #define INTC_ICR1	(INTC_BASE+0x1c)
28 #define INTC_INTPRI	(INTC_BASE+0x10)
29 #define INTC_INTREQ	(INTC_BASE+0x24)
30 #define INTC_INTMSK0	(INTC_BASE+0x44)
31 #define INTC_INTMSK1	(INTC_BASE+0x48)
32 #define INTC_INTMSK2	(INTC_BASE+0x40080)
33 #define INTC_INTMSKCLR0	(INTC_BASE+0x64)
34 #define INTC_INTMSKCLR1	(INTC_BASE+0x68)
35 #define INTC_INTMSKCLR2	(INTC_BASE+0x40084)
36 #define INTC_INT2MSKR	(INTC_BASE+0x40038)
37 #define INTC_INT2MSKCR	(INTC_BASE+0x4003c)
38 
39 /*
40  * Initialization. Try all known PCI access methods. Note that we support
41  * using both PCI BIOS and direct access: in such cases, we use I/O ports
42  * to access config space.
43  *
44  * Note that the platform specific initialization (BSC registers, and memory
45  * space mapping) will be called via the platform defined function
46  * pcibios_init_platform().
47  */
48 static int __init sh7780_pci_init(void)
49 {
50 	unsigned int id;
51 	int ret, match = 0;
52 
53 	pr_debug("PCI: Starting intialization.\n");
54 
55 	outl(0x00000001, SH7780_PCI_VCR2); /* Enable PCIC */
56 
57 	/* check for SH7780/SH7780R hardware */
58 	id = pci_read_reg(SH7780_PCIVID);
59 	if ((id & 0xffff) == SH7780_VENDOR_ID) {
60 		switch ((id >> 16) & 0xffff) {
61 		case SH7780_DEVICE_ID:
62 		case SH7781_DEVICE_ID:
63 		case SH7785_DEVICE_ID:
64 			match = 1;
65 			break;
66 		}
67 	}
68 
69 	if (unlikely(!match)) {
70 		printk(KERN_ERR "PCI: This is not an SH7780 (%x)\n", id);
71 		return -ENODEV;
72 	}
73 
74 	/* Setup the INTC */
75 	if (mach_is_7780se()) {
76 		/* ICR0: IRL=use separately */
77 		ctrl_outl(0x00C00020, INTC_ICR0);
78 		/* ICR1: detect low level(for 2ndcut) */
79 		ctrl_outl(0xAAAA0000, INTC_ICR1);
80 		/* INTPRI: priority=3(all) */
81 		ctrl_outl(0x33333333, INTC_INTPRI);
82 	}
83 
84 	if ((ret = sh4_pci_check_direct()) != 0)
85 		return ret;
86 
87 	return pcibios_init_platform();
88 }
89 core_initcall(sh7780_pci_init);
90 
91 int __init sh7780_pcic_init(struct sh4_pci_address_map *map)
92 {
93 	u32 word;
94 
95 	/*
96 	 * This code is unused for some boards as it is done in the
97 	 * bootloader and doing it here means the MAC addresses loaded
98 	 * by the bootloader get lost.
99 	 */
100 	if (!(map->flags & SH4_PCIC_NO_RESET)) {
101 		/* toggle PCI reset pin */
102 		word = SH4_PCICR_PREFIX | SH4_PCICR_PRST;
103 		pci_write_reg(word, SH4_PCICR);
104 		/* Wait for a long time... not 1 sec. but long enough */
105 		mdelay(100);
106 		word = SH4_PCICR_PREFIX;
107 		pci_write_reg(word, SH4_PCICR);
108 	}
109 
110 	/* set the command/status bits to:
111 	 * Wait Cycle Control + Parity Enable + Bus Master +
112 	 * Mem space enable
113 	 */
114 	pci_write_reg(0x00000046, SH7780_PCICMD);
115 
116 	/* define this host as the host bridge */
117 	word = PCI_BASE_CLASS_BRIDGE << 24;
118 	pci_write_reg(word, SH7780_PCIRID);
119 
120 	/* Set IO and Mem windows to local address
121 	 * Make PCI and local address the same for easy 1 to 1 mapping
122 	 * Window0 = map->window0.size @ non-cached area base = SDRAM
123 	 * Window1 = map->window1.size @ cached area base = SDRAM
124 	 */
125 	word = ((map->window0.size - 1) & 0x1ff00001) | 0x01;
126 	pci_write_reg(0x07f00001, SH4_PCILSR0);
127 	word = ((map->window1.size - 1) & 0x1ff00001) | 0x01;
128 	pci_write_reg(0x00000001, SH4_PCILSR1);
129 	/* Set the values on window 0 PCI config registers */
130 	word = P2SEGADDR(map->window0.base);
131 	pci_write_reg(0xa8000000, SH4_PCILAR0);
132 	pci_write_reg(0x08000000, SH7780_PCIMBAR0);
133 	/* Set the values on window 1 PCI config registers */
134 	word = P2SEGADDR(map->window1.base);
135 	pci_write_reg(0x00000000, SH4_PCILAR1);
136 	pci_write_reg(0x00000000, SH7780_PCIMBAR1);
137 
138 	/* Map IO space into PCI IO window
139 	 * The IO window is 64K-PCIBIOS_MIN_IO in size
140 	 * IO addresses will be translated to the
141 	 * PCI IO window base address
142 	 */
143 	pr_debug("PCI: Mapping IO address 0x%x - 0x%x to base 0x%x\n",
144 		 PCIBIOS_MIN_IO, (64 << 10),
145 		 SH7780_PCI_IO_BASE + PCIBIOS_MIN_IO);
146 
147 	/* NOTE: I'm ignoring the PCI error IRQs for now..
148 	 * TODO: add support for the internal error interrupts and
149 	 * DMA interrupts...
150 	 */
151 
152 	/* Apply any last-minute PCIC fixups */
153 	pci_fixup_pcic();
154 
155 	/* SH7780 init done, set central function init complete */
156 	/* use round robin mode to stop a device starving/overruning */
157 	word = SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO;
158 	pci_write_reg(word, SH4_PCICR);
159 
160 	return 1;
161 }
162