xref: /openbmc/linux/arch/mips/pci/pci-bcm63xx.c (revision 54cbac81)
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 <linux/delay.h>
14 #include <linux/clk.h>
15 #include <asm/bootinfo.h>
16 
17 #include <bcm63xx_reset.h>
18 
19 #include "pci-bcm63xx.h"
20 
21 /*
22  * Allow PCI to be disabled at runtime depending on board nvram
23  * configuration
24  */
25 int bcm63xx_pci_enabled;
26 
27 static struct resource bcm_pci_mem_resource = {
28 	.name   = "bcm63xx PCI memory space",
29 	.start  = BCM_PCI_MEM_BASE_PA,
30 	.end    = BCM_PCI_MEM_END_PA,
31 	.flags  = IORESOURCE_MEM
32 };
33 
34 static struct resource bcm_pci_io_resource = {
35 	.name   = "bcm63xx PCI IO space",
36 	.start  = BCM_PCI_IO_BASE_PA,
37 #ifdef CONFIG_CARDBUS
38 	.end    = BCM_PCI_IO_HALF_PA,
39 #else
40 	.end    = BCM_PCI_IO_END_PA,
41 #endif
42 	.flags  = IORESOURCE_IO
43 };
44 
45 struct pci_controller bcm63xx_controller = {
46 	.pci_ops	= &bcm63xx_pci_ops,
47 	.io_resource	= &bcm_pci_io_resource,
48 	.mem_resource	= &bcm_pci_mem_resource,
49 };
50 
51 /*
52  * We handle cardbus  via a fake Cardbus bridge,  memory and io spaces
53  * have to be  clearly separated from PCI one  since we have different
54  * memory decoder.
55  */
56 #ifdef CONFIG_CARDBUS
57 static struct resource bcm_cb_mem_resource = {
58 	.name   = "bcm63xx Cardbus memory space",
59 	.start  = BCM_CB_MEM_BASE_PA,
60 	.end    = BCM_CB_MEM_END_PA,
61 	.flags  = IORESOURCE_MEM
62 };
63 
64 static struct resource bcm_cb_io_resource = {
65 	.name   = "bcm63xx Cardbus IO space",
66 	.start  = BCM_PCI_IO_HALF_PA + 1,
67 	.end    = BCM_PCI_IO_END_PA,
68 	.flags  = IORESOURCE_IO
69 };
70 
71 struct pci_controller bcm63xx_cb_controller = {
72 	.pci_ops	= &bcm63xx_cb_ops,
73 	.io_resource	= &bcm_cb_io_resource,
74 	.mem_resource	= &bcm_cb_mem_resource,
75 };
76 #endif
77 
78 static struct resource bcm_pcie_mem_resource = {
79 	.name   = "bcm63xx PCIe memory space",
80 	.start  = BCM_PCIE_MEM_BASE_PA,
81 	.end    = BCM_PCIE_MEM_END_PA,
82 	.flags  = IORESOURCE_MEM,
83 };
84 
85 static struct resource bcm_pcie_io_resource = {
86 	.name   = "bcm63xx PCIe IO space",
87 	.start  = 0,
88 	.end    = 0,
89 	.flags  = 0,
90 };
91 
92 struct pci_controller bcm63xx_pcie_controller = {
93 	.pci_ops	= &bcm63xx_pcie_ops,
94 	.io_resource	= &bcm_pcie_io_resource,
95 	.mem_resource	= &bcm_pcie_mem_resource,
96 };
97 
98 static u32 bcm63xx_int_cfg_readl(u32 reg)
99 {
100 	u32 tmp;
101 
102 	tmp = reg & MPI_PCICFGCTL_CFGADDR_MASK;
103 	tmp |= MPI_PCICFGCTL_WRITEEN_MASK;
104 	bcm_mpi_writel(tmp, MPI_PCICFGCTL_REG);
105 	iob();
106 	return bcm_mpi_readl(MPI_PCICFGDATA_REG);
107 }
108 
109 static void bcm63xx_int_cfg_writel(u32 val, u32 reg)
110 {
111 	u32 tmp;
112 
113 	tmp = reg & MPI_PCICFGCTL_CFGADDR_MASK;
114 	tmp |=  MPI_PCICFGCTL_WRITEEN_MASK;
115 	bcm_mpi_writel(tmp, MPI_PCICFGCTL_REG);
116 	bcm_mpi_writel(val, MPI_PCICFGDATA_REG);
117 }
118 
119 void __iomem *pci_iospace_start;
120 
121 static void __init bcm63xx_reset_pcie(void)
122 {
123 	u32 val;
124 
125 	/* enable SERDES */
126 	val = bcm_misc_readl(MISC_SERDES_CTRL_REG);
127 	val |= SERDES_PCIE_EN | SERDES_PCIE_EXD_EN;
128 	bcm_misc_writel(val, MISC_SERDES_CTRL_REG);
129 
130 	/* reset the PCIe core */
131 	bcm63xx_core_set_reset(BCM63XX_RESET_PCIE, 1);
132 	bcm63xx_core_set_reset(BCM63XX_RESET_PCIE_EXT, 1);
133 	mdelay(10);
134 
135 	bcm63xx_core_set_reset(BCM63XX_RESET_PCIE, 0);
136 	mdelay(10);
137 
138 	bcm63xx_core_set_reset(BCM63XX_RESET_PCIE_EXT, 0);
139 	mdelay(200);
140 }
141 
142 static struct clk *pcie_clk;
143 
144 static int __init bcm63xx_register_pcie(void)
145 {
146 	u32 val;
147 
148 	/* enable clock */
149 	pcie_clk = clk_get(NULL, "pcie");
150 	if (IS_ERR_OR_NULL(pcie_clk))
151 		return -ENODEV;
152 
153 	clk_prepare_enable(pcie_clk);
154 
155 	bcm63xx_reset_pcie();
156 
157 	/* configure the PCIe bridge */
158 	val = bcm_pcie_readl(PCIE_BRIDGE_OPT1_REG);
159 	val |= OPT1_RD_BE_OPT_EN;
160 	val |= OPT1_RD_REPLY_BE_FIX_EN;
161 	val |= OPT1_PCIE_BRIDGE_HOLE_DET_EN;
162 	val |= OPT1_L1_INT_STATUS_MASK_POL;
163 	bcm_pcie_writel(val, PCIE_BRIDGE_OPT1_REG);
164 
165 	/* setup the interrupts */
166 	val = bcm_pcie_readl(PCIE_BRIDGE_RC_INT_MASK_REG);
167 	val |= PCIE_RC_INT_A | PCIE_RC_INT_B | PCIE_RC_INT_C | PCIE_RC_INT_D;
168 	bcm_pcie_writel(val, PCIE_BRIDGE_RC_INT_MASK_REG);
169 
170 	val = bcm_pcie_readl(PCIE_BRIDGE_OPT2_REG);
171 	/* enable credit checking and error checking */
172 	val |= OPT2_TX_CREDIT_CHK_EN;
173 	val |= OPT2_UBUS_UR_DECODE_DIS;
174 
175 	/* set device bus/func for the pcie device */
176 	val |= (PCIE_BUS_DEVICE << OPT2_CFG_TYPE1_BUS_NO_SHIFT);
177 	val |= OPT2_CFG_TYPE1_BD_SEL;
178 	bcm_pcie_writel(val, PCIE_BRIDGE_OPT2_REG);
179 
180 	/* setup class code as bridge */
181 	val = bcm_pcie_readl(PCIE_IDVAL3_REG);
182 	val &= ~IDVAL3_CLASS_CODE_MASK;
183 	val |= (PCI_CLASS_BRIDGE_PCI << IDVAL3_SUBCLASS_SHIFT);
184 	bcm_pcie_writel(val, PCIE_IDVAL3_REG);
185 
186 	/* disable bar1 size */
187 	val = bcm_pcie_readl(PCIE_CONFIG2_REG);
188 	val &= ~CONFIG2_BAR1_SIZE_MASK;
189 	bcm_pcie_writel(val, PCIE_CONFIG2_REG);
190 
191 	/* set bar0 to little endian */
192 	val = (BCM_PCIE_MEM_BASE_PA >> 20) << BASEMASK_BASE_SHIFT;
193 	val |= (BCM_PCIE_MEM_BASE_PA >> 20) << BASEMASK_MASK_SHIFT;
194 	val |= BASEMASK_REMAP_EN;
195 	bcm_pcie_writel(val, PCIE_BRIDGE_BAR0_BASEMASK_REG);
196 
197 	val = (BCM_PCIE_MEM_BASE_PA >> 20) << REBASE_ADDR_BASE_SHIFT;
198 	bcm_pcie_writel(val, PCIE_BRIDGE_BAR0_REBASE_ADDR_REG);
199 
200 	register_pci_controller(&bcm63xx_pcie_controller);
201 
202 	return 0;
203 }
204 
205 static int __init bcm63xx_register_pci(void)
206 {
207 	unsigned int mem_size;
208 	u32 val;
209 	/*
210 	 * configuration  access are  done through  IO space,  remap 4
211 	 * first bytes to access it from CPU.
212 	 *
213 	 * this means that  no io access from CPU  should happen while
214 	 * we do a configuration cycle,  but there's no way we can add
215 	 * a spinlock for each io access, so this is currently kind of
216 	 * broken on SMP.
217 	 */
218 	pci_iospace_start = ioremap_nocache(BCM_PCI_IO_BASE_PA, 4);
219 	if (!pci_iospace_start)
220 		return -ENOMEM;
221 
222 	/* setup local bus to PCI access (PCI memory) */
223 	val = BCM_PCI_MEM_BASE_PA & MPI_L2P_BASE_MASK;
224 	bcm_mpi_writel(val, MPI_L2PMEMBASE1_REG);
225 	bcm_mpi_writel(~(BCM_PCI_MEM_SIZE - 1), MPI_L2PMEMRANGE1_REG);
226 	bcm_mpi_writel(val | MPI_L2PREMAP_ENABLED_MASK, MPI_L2PMEMREMAP1_REG);
227 
228 	/* set Cardbus IDSEL (type 0 cfg access on primary bus for
229 	 * this IDSEL will be done on Cardbus instead) */
230 	val = bcm_pcmcia_readl(PCMCIA_C1_REG);
231 	val &= ~PCMCIA_C1_CBIDSEL_MASK;
232 	val |= (CARDBUS_PCI_IDSEL << PCMCIA_C1_CBIDSEL_SHIFT);
233 	bcm_pcmcia_writel(val, PCMCIA_C1_REG);
234 
235 #ifdef CONFIG_CARDBUS
236 	/* setup local bus to PCI access (Cardbus memory) */
237 	val = BCM_CB_MEM_BASE_PA & MPI_L2P_BASE_MASK;
238 	bcm_mpi_writel(val, MPI_L2PMEMBASE2_REG);
239 	bcm_mpi_writel(~(BCM_CB_MEM_SIZE - 1), MPI_L2PMEMRANGE2_REG);
240 	val |= MPI_L2PREMAP_ENABLED_MASK | MPI_L2PREMAP_IS_CARDBUS_MASK;
241 	bcm_mpi_writel(val, MPI_L2PMEMREMAP2_REG);
242 #else
243 	/* disable second access windows */
244 	bcm_mpi_writel(0, MPI_L2PMEMREMAP2_REG);
245 #endif
246 
247 	/* setup local bus  to PCI access (IO memory),  we have only 1
248 	 * IO window  for both PCI  and cardbus, but it  cannot handle
249 	 * both  at the  same time,  assume standard  PCI for  now, if
250 	 * cardbus card has  IO zone, PCI fixup will  change window to
251 	 * cardbus */
252 	val = BCM_PCI_IO_BASE_PA & MPI_L2P_BASE_MASK;
253 	bcm_mpi_writel(val, MPI_L2PIOBASE_REG);
254 	bcm_mpi_writel(~(BCM_PCI_IO_SIZE - 1), MPI_L2PIORANGE_REG);
255 	bcm_mpi_writel(val | MPI_L2PREMAP_ENABLED_MASK, MPI_L2PIOREMAP_REG);
256 
257 	/* enable PCI related GPIO pins */
258 	bcm_mpi_writel(MPI_LOCBUSCTL_EN_PCI_GPIO_MASK, MPI_LOCBUSCTL_REG);
259 
260 	/* setup PCI to local bus access, used by PCI device to target
261 	 * local RAM while bus mastering */
262 	bcm63xx_int_cfg_writel(0, PCI_BASE_ADDRESS_3);
263 	if (BCMCPU_IS_6358() || BCMCPU_IS_6368())
264 		val = MPI_SP0_REMAP_ENABLE_MASK;
265 	else
266 		val = 0;
267 	bcm_mpi_writel(val, MPI_SP0_REMAP_REG);
268 
269 	bcm63xx_int_cfg_writel(0x0, PCI_BASE_ADDRESS_4);
270 	bcm_mpi_writel(0, MPI_SP1_REMAP_REG);
271 
272 	mem_size = bcm63xx_get_memory_size();
273 
274 	/* 6348 before rev b0 exposes only 16 MB of RAM memory through
275 	 * PCI, throw a warning if we have more memory */
276 	if (BCMCPU_IS_6348() && (bcm63xx_get_cpu_rev() & 0xf0) == 0xa0) {
277 		if (mem_size > (16 * 1024 * 1024))
278 			printk(KERN_WARNING "bcm63xx: this CPU "
279 			       "revision cannot handle more than 16MB "
280 			       "of RAM for PCI bus mastering\n");
281 	} else {
282 		/* setup sp0 range to local RAM size */
283 		bcm_mpi_writel(~(mem_size - 1), MPI_SP0_RANGE_REG);
284 		bcm_mpi_writel(0, MPI_SP1_RANGE_REG);
285 	}
286 
287 	/* change  host bridge  retry  counter to  infinite number  of
288 	 * retry,  needed for  some broadcom  wifi cards  with Silicon
289 	 * Backplane bus where access to srom seems very slow  */
290 	val = bcm63xx_int_cfg_readl(BCMPCI_REG_TIMERS);
291 	val &= ~REG_TIMER_RETRY_MASK;
292 	bcm63xx_int_cfg_writel(val, BCMPCI_REG_TIMERS);
293 
294 	/* enable memory decoder and bus mastering */
295 	val = bcm63xx_int_cfg_readl(PCI_COMMAND);
296 	val |= (PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
297 	bcm63xx_int_cfg_writel(val, PCI_COMMAND);
298 
299 	/* enable read prefetching & disable byte swapping for bus
300 	 * mastering transfers */
301 	val = bcm_mpi_readl(MPI_PCIMODESEL_REG);
302 	val &= ~MPI_PCIMODESEL_BAR1_NOSWAP_MASK;
303 	val &= ~MPI_PCIMODESEL_BAR2_NOSWAP_MASK;
304 	val &= ~MPI_PCIMODESEL_PREFETCH_MASK;
305 	val |= (8 << MPI_PCIMODESEL_PREFETCH_SHIFT);
306 	bcm_mpi_writel(val, MPI_PCIMODESEL_REG);
307 
308 	/* enable pci interrupt */
309 	val = bcm_mpi_readl(MPI_LOCINT_REG);
310 	val |= MPI_LOCINT_MASK(MPI_LOCINT_EXT_PCI_INT);
311 	bcm_mpi_writel(val, MPI_LOCINT_REG);
312 
313 	register_pci_controller(&bcm63xx_controller);
314 
315 #ifdef CONFIG_CARDBUS
316 	register_pci_controller(&bcm63xx_cb_controller);
317 #endif
318 
319 	/* mark memory space used for IO mapping as reserved */
320 	request_mem_region(BCM_PCI_IO_BASE_PA, BCM_PCI_IO_SIZE,
321 			   "bcm63xx PCI IO space");
322 	return 0;
323 }
324 
325 
326 static int __init bcm63xx_pci_init(void)
327 {
328 	if (!bcm63xx_pci_enabled)
329 		return -ENODEV;
330 
331 	switch (bcm63xx_get_cpu_id()) {
332 	case BCM6328_CPU_ID:
333 		return bcm63xx_register_pcie();
334 	case BCM6348_CPU_ID:
335 	case BCM6358_CPU_ID:
336 	case BCM6368_CPU_ID:
337 		return bcm63xx_register_pci();
338 	default:
339 		return -ENODEV;
340 	}
341 }
342 
343 arch_initcall(bcm63xx_pci_init);
344