xref: /linux/arch/sh/drivers/pci/pci-sh7780.c (revision 85b59f5bb24aeca1a987cbb206e228bf630c8327)
1 /*
2  * Low-Level PCI Support for the SH7780
3  *
4  *  Copyright (C) 2005 - 2010  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/errno.h>
15 #include <linux/delay.h>
16 #include <linux/log2.h>
17 #include "pci-sh4.h"
18 #include <asm/mmu.h>
19 #include <asm/sizes.h>
20 
21 static struct resource sh7785_io_resource = {
22 	.name	= "SH7785_IO",
23 	.start	= 0x1000,
24 	.end	= SH7780_PCI_IO_SIZE - 1,
25 	.flags	= IORESOURCE_IO
26 };
27 
28 static struct resource sh7785_mem_resource = {
29 	.name	= "SH7785_mem",
30 	.start	= SH7780_PCI_MEMORY_BASE,
31 	.end	= SH7780_PCI_MEMORY_BASE + SH7780_PCI_MEM_SIZE - 1,
32 	.flags	= IORESOURCE_MEM
33 };
34 
35 static struct pci_channel sh7780_pci_controller = {
36 	.pci_ops	= &sh4_pci_ops,
37 	.mem_resource	= &sh7785_mem_resource,
38 	.mem_offset	= 0x00000000,
39 	.io_resource	= &sh7785_io_resource,
40 	.io_offset	= 0x00000000,
41 	.io_map_base	= SH7780_PCI_IO_BASE,
42 };
43 
44 static void __init sh7780_pci66_init(struct pci_channel *hose)
45 {
46 	unsigned int tmp;
47 
48 	if (!pci_is_66mhz_capable(hose, 0, 0))
49 		return;
50 
51 	/* Enable register access */
52 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
53 	tmp |= SH4_PCICR_PREFIX;
54 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
55 
56 	/* Enable 66MHz operation */
57 	tmp = __raw_readw(hose->reg_base + PCI_STATUS);
58 	tmp |= PCI_STATUS_66MHZ;
59 	__raw_writew(tmp, hose->reg_base + PCI_STATUS);
60 
61 	/* Done */
62 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
63 	tmp |= SH4_PCICR_PREFIX | SH4_PCICR_CFIN;
64 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
65 }
66 
67 static int __init sh7780_pci_init(void)
68 {
69 	struct pci_channel *chan = &sh7780_pci_controller;
70 	phys_addr_t memphys;
71 	size_t memsize;
72 	unsigned int id;
73 	const char *type;
74 
75 	printk(KERN_NOTICE "PCI: Starting intialization.\n");
76 
77 	chan->reg_base = 0xfe040000;
78 
79 	/* Enable CPU access to the PCIC registers. */
80 	__raw_writel(PCIECR_ENBL, PCIECR);
81 
82 	/* Reset */
83 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_PRST,
84 		     chan->reg_base + SH4_PCICR);
85 
86 	/*
87 	 * Wait for it to come back up. The spec says to allow for up to
88 	 * 1 second after toggling the reset pin, but in practice 100ms
89 	 * is more than enough.
90 	 */
91 	mdelay(100);
92 
93 	id = __raw_readw(chan->reg_base + PCI_VENDOR_ID);
94 	if (id != PCI_VENDOR_ID_RENESAS) {
95 		printk(KERN_ERR "PCI: Unknown vendor ID 0x%04x.\n", id);
96 		return -ENODEV;
97 	}
98 
99 	id = __raw_readw(chan->reg_base + PCI_DEVICE_ID);
100 	type = (id == PCI_DEVICE_ID_RENESAS_SH7763) ? "SH7763" :
101 	       (id == PCI_DEVICE_ID_RENESAS_SH7780) ? "SH7780" :
102 	       (id == PCI_DEVICE_ID_RENESAS_SH7781) ? "SH7781" :
103 	       (id == PCI_DEVICE_ID_RENESAS_SH7785) ? "SH7785" :
104 					  NULL;
105 	if (unlikely(!type)) {
106 		printk(KERN_ERR "PCI: Found an unsupported Renesas host "
107 		       "controller, device id 0x%04x.\n", id);
108 		return -EINVAL;
109 	}
110 
111 	printk(KERN_NOTICE "PCI: Found a Renesas %s host "
112 	       "controller, revision %d.\n", type,
113 	       __raw_readb(chan->reg_base + PCI_REVISION_ID));
114 
115 	/*
116 	 * Now throw it in to register initialization mode and
117 	 * start the real work.
118 	 */
119 	__raw_writel(SH4_PCICR_PREFIX, chan->reg_base + SH4_PCICR);
120 
121 	__raw_writel(0, chan->reg_base + PCI_BASE_ADDRESS_0);
122 
123 	memphys = __pa(memory_start);
124 	memsize = roundup_pow_of_two(memory_end - memory_start);
125 
126 	/*
127 	 * If there's more than 512MB of memory, we need to roll over to
128 	 * LAR1/LSR1.
129 	 */
130 	if (memsize > SZ_512M) {
131 		__raw_writel(memphys + SZ_512M, chan->reg_base + SH4_PCILAR1);
132 		__raw_writel((((memsize - SZ_512M) - SZ_1M) & 0x1ff00000) | 1,
133 			     chan->reg_base + SH4_PCILSR1);
134 		memsize = SZ_512M;
135 	} else {
136 		/*
137 		 * Otherwise just zero it out and disable it.
138 		 */
139 		__raw_writel(0, chan->reg_base + SH4_PCILAR1);
140 		__raw_writel(0, chan->reg_base + SH4_PCILSR1);
141 	}
142 
143 	/*
144 	 * LAR0/LSR0 covers up to the first 512MB, which is enough to
145 	 * cover all of lowmem on most platforms.
146 	 */
147 	__raw_writel(memphys, chan->reg_base + SH4_PCILAR0);
148 	__raw_writel(((memsize - SZ_1M) & 0x1ff00000) | 1,
149 		     chan->reg_base + SH4_PCILSR0);
150 
151 	/* Clear out PCI arbiter IRQs */
152 	__raw_writel(0, chan->reg_base + SH4_PCIAINT);
153 
154 	/* Unmask all of the arbiter IRQs. */
155 	__raw_writel(SH4_PCIAINT_MBKN | SH4_PCIAINT_TBTO | SH4_PCIAINT_MBTO | \
156 		     SH4_PCIAINT_TABT | SH4_PCIAINT_MABT | SH4_PCIAINT_RDPE | \
157 		     SH4_PCIAINT_WDPE, chan->reg_base + SH4_PCIAINTM);
158 
159 	/* Clear all error conditions */
160 	__raw_writew(PCI_STATUS_DETECTED_PARITY  | \
161 		     PCI_STATUS_SIG_SYSTEM_ERROR | \
162 		     PCI_STATUS_REC_MASTER_ABORT | \
163 		     PCI_STATUS_REC_TARGET_ABORT | \
164 		     PCI_STATUS_SIG_TARGET_ABORT | \
165 		     PCI_STATUS_PARITY, chan->reg_base + PCI_STATUS);
166 
167 	__raw_writew(PCI_COMMAND_SERR | PCI_COMMAND_WAIT | \
168 		     PCI_COMMAND_PARITY | PCI_COMMAND_MASTER | \
169 		     PCI_COMMAND_MEMORY, chan->reg_base + PCI_COMMAND);
170 
171 	/* Unmask all of the PCI IRQs */
172 	__raw_writel(SH4_PCIINTM_TTADIM  | SH4_PCIINTM_TMTOIM  | \
173 		     SH4_PCIINTM_MDEIM   | SH4_PCIINTM_APEDIM  | \
174 		     SH4_PCIINTM_SDIM    | SH4_PCIINTM_DPEITWM | \
175 		     SH4_PCIINTM_PEDITRM | SH4_PCIINTM_TADIMM  | \
176 		     SH4_PCIINTM_MADIMM  | SH4_PCIINTM_MWPDIM  | \
177 		     SH4_PCIINTM_MRDPEIM, chan->reg_base + SH4_PCIINTM);
178 
179 	/*
180 	 * Disable the cache snoop controller for non-coherent DMA.
181 	 */
182 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR0);
183 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR0);
184 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR1);
185 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR1);
186 
187 	__raw_writel(0xfd000000, chan->reg_base + SH7780_PCIMBR0);
188 	__raw_writel(0x00fc0000, chan->reg_base + SH7780_PCIMBMR0);
189 
190 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBR);
191 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBMR);
192 
193 	/*
194 	 * Initialization mode complete, release the control register and
195 	 * enable round robin mode to stop device overruns/starvation.
196 	 */
197 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO,
198 		     chan->reg_base + SH4_PCICR);
199 
200 	register_pci_controller(chan);
201 
202 	sh7780_pci66_init(chan);
203 
204 	printk(KERN_NOTICE "PCI: Running at %dMHz.\n",
205 	       (__raw_readw(chan->reg_base + PCI_STATUS) & PCI_STATUS_66MHZ) ?
206 	       66 : 33);
207 
208 	return 0;
209 }
210 arch_initcall(sh7780_pci_init);
211