xref: /openbmc/linux/arch/mips/pci/pci-bcm63xx.c (revision b6dcefde)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
7  */
8 
9 #include <linux/types.h>
10 #include <linux/pci.h>
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <asm/bootinfo.h>
14 
15 #include "pci-bcm63xx.h"
16 
17 /*
18  * Allow PCI to be disabled at runtime depending on board nvram
19  * configuration
20  */
21 int bcm63xx_pci_enabled;
22 
23 static struct resource bcm_pci_mem_resource = {
24 	.name   = "bcm63xx PCI memory space",
25 	.start  = BCM_PCI_MEM_BASE_PA,
26 	.end    = BCM_PCI_MEM_END_PA,
27 	.flags  = IORESOURCE_MEM
28 };
29 
30 static struct resource bcm_pci_io_resource = {
31 	.name   = "bcm63xx PCI IO space",
32 	.start  = BCM_PCI_IO_BASE_PA,
33 #ifdef CONFIG_CARDBUS
34 	.end    = BCM_PCI_IO_HALF_PA,
35 #else
36 	.end    = BCM_PCI_IO_END_PA,
37 #endif
38 	.flags  = IORESOURCE_IO
39 };
40 
41 struct pci_controller bcm63xx_controller = {
42 	.pci_ops	= &bcm63xx_pci_ops,
43 	.io_resource	= &bcm_pci_io_resource,
44 	.mem_resource	= &bcm_pci_mem_resource,
45 };
46 
47 /*
48  * We handle cardbus  via a fake Cardbus bridge,  memory and io spaces
49  * have to be  clearly separated from PCI one  since we have different
50  * memory decoder.
51  */
52 #ifdef CONFIG_CARDBUS
53 static struct resource bcm_cb_mem_resource = {
54 	.name   = "bcm63xx Cardbus memory space",
55 	.start  = BCM_CB_MEM_BASE_PA,
56 	.end    = BCM_CB_MEM_END_PA,
57 	.flags  = IORESOURCE_MEM
58 };
59 
60 static struct resource bcm_cb_io_resource = {
61 	.name   = "bcm63xx Cardbus IO space",
62 	.start  = BCM_PCI_IO_HALF_PA + 1,
63 	.end    = BCM_PCI_IO_END_PA,
64 	.flags  = IORESOURCE_IO
65 };
66 
67 struct pci_controller bcm63xx_cb_controller = {
68 	.pci_ops	= &bcm63xx_cb_ops,
69 	.io_resource	= &bcm_cb_io_resource,
70 	.mem_resource	= &bcm_cb_mem_resource,
71 };
72 #endif
73 
74 static u32 bcm63xx_int_cfg_readl(u32 reg)
75 {
76 	u32 tmp;
77 
78 	tmp = reg & MPI_PCICFGCTL_CFGADDR_MASK;
79 	tmp |= MPI_PCICFGCTL_WRITEEN_MASK;
80 	bcm_mpi_writel(tmp, MPI_PCICFGCTL_REG);
81 	iob();
82 	return bcm_mpi_readl(MPI_PCICFGDATA_REG);
83 }
84 
85 static void bcm63xx_int_cfg_writel(u32 val, u32 reg)
86 {
87 	u32 tmp;
88 
89 	tmp = reg & MPI_PCICFGCTL_CFGADDR_MASK;
90 	tmp |=  MPI_PCICFGCTL_WRITEEN_MASK;
91 	bcm_mpi_writel(tmp, MPI_PCICFGCTL_REG);
92 	bcm_mpi_writel(val, MPI_PCICFGDATA_REG);
93 }
94 
95 void __iomem *pci_iospace_start;
96 
97 static int __init bcm63xx_pci_init(void)
98 {
99 	unsigned int mem_size;
100 	u32 val;
101 
102 	if (!BCMCPU_IS_6348() && !BCMCPU_IS_6358())
103 		return -ENODEV;
104 
105 	if (!bcm63xx_pci_enabled)
106 		return -ENODEV;
107 
108 	/*
109 	 * configuration  access are  done through  IO space,  remap 4
110 	 * first bytes to access it from CPU.
111 	 *
112 	 * this means that  no io access from CPU  should happen while
113 	 * we do a configuration cycle,  but there's no way we can add
114 	 * a spinlock for each io access, so this is currently kind of
115 	 * broken on SMP.
116 	 */
117 	pci_iospace_start = ioremap_nocache(BCM_PCI_IO_BASE_PA, 4);
118 	if (!pci_iospace_start)
119 		return -ENOMEM;
120 
121 	/* setup local bus to PCI access (PCI memory) */
122 	val = BCM_PCI_MEM_BASE_PA & MPI_L2P_BASE_MASK;
123 	bcm_mpi_writel(val, MPI_L2PMEMBASE1_REG);
124 	bcm_mpi_writel(~(BCM_PCI_MEM_SIZE - 1), MPI_L2PMEMRANGE1_REG);
125 	bcm_mpi_writel(val | MPI_L2PREMAP_ENABLED_MASK, MPI_L2PMEMREMAP1_REG);
126 
127 	/* set Cardbus IDSEL (type 0 cfg access on primary bus for
128 	 * this IDSEL will be done on Cardbus instead) */
129 	val = bcm_pcmcia_readl(PCMCIA_C1_REG);
130 	val &= ~PCMCIA_C1_CBIDSEL_MASK;
131 	val |= (CARDBUS_PCI_IDSEL << PCMCIA_C1_CBIDSEL_SHIFT);
132 	bcm_pcmcia_writel(val, PCMCIA_C1_REG);
133 
134 #ifdef CONFIG_CARDBUS
135 	/* setup local bus to PCI access (Cardbus memory) */
136 	val = BCM_CB_MEM_BASE_PA & MPI_L2P_BASE_MASK;
137 	bcm_mpi_writel(val, MPI_L2PMEMBASE2_REG);
138 	bcm_mpi_writel(~(BCM_CB_MEM_SIZE - 1), MPI_L2PMEMRANGE2_REG);
139 	val |= MPI_L2PREMAP_ENABLED_MASK | MPI_L2PREMAP_IS_CARDBUS_MASK;
140 	bcm_mpi_writel(val, MPI_L2PMEMREMAP2_REG);
141 #else
142 	/* disable second access windows */
143 	bcm_mpi_writel(0, MPI_L2PMEMREMAP2_REG);
144 #endif
145 
146 	/* setup local bus  to PCI access (IO memory),  we have only 1
147 	 * IO window  for both PCI  and cardbus, but it  cannot handle
148 	 * both  at the  same time,  assume standard  PCI for  now, if
149 	 * cardbus card has  IO zone, PCI fixup will  change window to
150 	 * cardbus */
151 	val = BCM_PCI_IO_BASE_PA & MPI_L2P_BASE_MASK;
152 	bcm_mpi_writel(val, MPI_L2PIOBASE_REG);
153 	bcm_mpi_writel(~(BCM_PCI_IO_SIZE - 1), MPI_L2PIORANGE_REG);
154 	bcm_mpi_writel(val | MPI_L2PREMAP_ENABLED_MASK, MPI_L2PIOREMAP_REG);
155 
156 	/* enable PCI related GPIO pins */
157 	bcm_mpi_writel(MPI_LOCBUSCTL_EN_PCI_GPIO_MASK, MPI_LOCBUSCTL_REG);
158 
159 	/* setup PCI to local bus access, used by PCI device to target
160 	 * local RAM while bus mastering */
161 	bcm63xx_int_cfg_writel(0, PCI_BASE_ADDRESS_3);
162 	if (BCMCPU_IS_6358())
163 		val = MPI_SP0_REMAP_ENABLE_MASK;
164 	else
165 		val = 0;
166 	bcm_mpi_writel(val, MPI_SP0_REMAP_REG);
167 
168 	bcm63xx_int_cfg_writel(0x0, PCI_BASE_ADDRESS_4);
169 	bcm_mpi_writel(0, MPI_SP1_REMAP_REG);
170 
171 	mem_size = bcm63xx_get_memory_size();
172 
173 	/* 6348 before rev b0 exposes only 16 MB of RAM memory through
174 	 * PCI, throw a warning if we have more memory */
175 	if (BCMCPU_IS_6348() && (bcm63xx_get_cpu_rev() & 0xf0) == 0xa0) {
176 		if (mem_size > (16 * 1024 * 1024))
177 			printk(KERN_WARNING "bcm63xx: this CPU "
178 			       "revision cannot handle more than 16MB "
179 			       "of RAM for PCI bus mastering\n");
180 	} else {
181 		/* setup sp0 range to local RAM size */
182 		bcm_mpi_writel(~(mem_size - 1), MPI_SP0_RANGE_REG);
183 		bcm_mpi_writel(0, MPI_SP1_RANGE_REG);
184 	}
185 
186 	/* change  host bridge  retry  counter to  infinite number  of
187 	 * retry,  needed for  some broadcom  wifi cards  with Silicon
188 	 * Backplane bus where access to srom seems very slow  */
189 	val = bcm63xx_int_cfg_readl(BCMPCI_REG_TIMERS);
190 	val &= ~REG_TIMER_RETRY_MASK;
191 	bcm63xx_int_cfg_writel(val, BCMPCI_REG_TIMERS);
192 
193 	/* enable memory decoder and bus mastering */
194 	val = bcm63xx_int_cfg_readl(PCI_COMMAND);
195 	val |= (PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
196 	bcm63xx_int_cfg_writel(val, PCI_COMMAND);
197 
198 	/* enable read prefetching & disable byte swapping for bus
199 	 * mastering transfers */
200 	val = bcm_mpi_readl(MPI_PCIMODESEL_REG);
201 	val &= ~MPI_PCIMODESEL_BAR1_NOSWAP_MASK;
202 	val &= ~MPI_PCIMODESEL_BAR2_NOSWAP_MASK;
203 	val &= ~MPI_PCIMODESEL_PREFETCH_MASK;
204 	val |= (8 << MPI_PCIMODESEL_PREFETCH_SHIFT);
205 	bcm_mpi_writel(val, MPI_PCIMODESEL_REG);
206 
207 	/* enable pci interrupt */
208 	val = bcm_mpi_readl(MPI_LOCINT_REG);
209 	val |= MPI_LOCINT_MASK(MPI_LOCINT_EXT_PCI_INT);
210 	bcm_mpi_writel(val, MPI_LOCINT_REG);
211 
212 	register_pci_controller(&bcm63xx_controller);
213 
214 #ifdef CONFIG_CARDBUS
215 	register_pci_controller(&bcm63xx_cb_controller);
216 #endif
217 
218 	/* mark memory space used for IO mapping as reserved */
219 	request_mem_region(BCM_PCI_IO_BASE_PA, BCM_PCI_IO_SIZE,
220 			   "bcm63xx PCI IO space");
221 	return 0;
222 }
223 
224 arch_initcall(bcm63xx_pci_init);
225