1 /*
2  *  This program is free software; you can redistribute it and/or modify it
3  *  under the terms of the GNU General Public License version 2 as published
4  *  by the Free Software Foundation.
5  *
6  *  Copyright (C) 2010 John Crispin <blogic@openwrt.org>
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/mm.h>
15 #include <linux/vmalloc.h>
16 #include <linux/export.h>
17 #include <linux/platform_device.h>
18 
19 #include <asm/pci.h>
20 #include <asm/gpio.h>
21 #include <asm/addrspace.h>
22 
23 #include <lantiq_soc.h>
24 #include <lantiq_irq.h>
25 #include <lantiq_platform.h>
26 
27 #include "pci-lantiq.h"
28 
29 #define LTQ_PCI_CFG_BASE		0x17000000
30 #define LTQ_PCI_CFG_SIZE		0x00008000
31 #define LTQ_PCI_MEM_BASE		0x18000000
32 #define LTQ_PCI_MEM_SIZE		0x02000000
33 #define LTQ_PCI_IO_BASE			0x1AE00000
34 #define LTQ_PCI_IO_SIZE			0x00200000
35 
36 #define PCI_CR_FCI_ADDR_MAP0		0x00C0
37 #define PCI_CR_FCI_ADDR_MAP1		0x00C4
38 #define PCI_CR_FCI_ADDR_MAP2		0x00C8
39 #define PCI_CR_FCI_ADDR_MAP3		0x00CC
40 #define PCI_CR_FCI_ADDR_MAP4		0x00D0
41 #define PCI_CR_FCI_ADDR_MAP5		0x00D4
42 #define PCI_CR_FCI_ADDR_MAP6		0x00D8
43 #define PCI_CR_FCI_ADDR_MAP7		0x00DC
44 #define PCI_CR_CLK_CTRL			0x0000
45 #define PCI_CR_PCI_MOD			0x0030
46 #define PCI_CR_PC_ARB			0x0080
47 #define PCI_CR_FCI_ADDR_MAP11hg		0x00E4
48 #define PCI_CR_BAR11MASK		0x0044
49 #define PCI_CR_BAR12MASK		0x0048
50 #define PCI_CR_BAR13MASK		0x004C
51 #define PCI_CS_BASE_ADDR1		0x0010
52 #define PCI_CR_PCI_ADDR_MAP11		0x0064
53 #define PCI_CR_FCI_BURST_LENGTH		0x00E8
54 #define PCI_CR_PCI_EOI			0x002C
55 #define PCI_CS_STS_CMD			0x0004
56 
57 #define PCI_MASTER0_REQ_MASK_2BITS	8
58 #define PCI_MASTER1_REQ_MASK_2BITS	10
59 #define PCI_MASTER2_REQ_MASK_2BITS	12
60 #define INTERNAL_ARB_ENABLE_BIT		0
61 
62 #define LTQ_CGU_IFCCR		0x0018
63 #define LTQ_CGU_PCICR		0x0034
64 
65 #define ltq_pci_w32(x, y)	ltq_w32((x), ltq_pci_membase + (y))
66 #define ltq_pci_r32(x)		ltq_r32(ltq_pci_membase + (x))
67 
68 #define ltq_pci_cfg_w32(x, y)	ltq_w32((x), ltq_pci_mapped_cfg + (y))
69 #define ltq_pci_cfg_r32(x)	ltq_r32(ltq_pci_mapped_cfg + (x))
70 
71 struct ltq_pci_gpio_map {
72 	int pin;
73 	int alt0;
74 	int alt1;
75 	int dir;
76 	char *name;
77 };
78 
79 /* the pci core can make use of the following gpios */
80 static struct ltq_pci_gpio_map ltq_pci_gpio_map[] = {
81 	{ 0, 1, 0, 0, "pci-exin0" },
82 	{ 1, 1, 0, 0, "pci-exin1" },
83 	{ 2, 1, 0, 0, "pci-exin2" },
84 	{ 39, 1, 0, 0, "pci-exin3" },
85 	{ 10, 1, 0, 0, "pci-exin4" },
86 	{ 9, 1, 0, 0, "pci-exin5" },
87 	{ 30, 1, 0, 1, "pci-gnt1" },
88 	{ 23, 1, 0, 1, "pci-gnt2" },
89 	{ 19, 1, 0, 1, "pci-gnt3" },
90 	{ 38, 1, 0, 1, "pci-gnt4" },
91 	{ 29, 1, 0, 0, "pci-req1" },
92 	{ 31, 1, 0, 0, "pci-req2" },
93 	{ 3, 1, 0, 0, "pci-req3" },
94 	{ 37, 1, 0, 0, "pci-req4" },
95 };
96 
97 __iomem void *ltq_pci_mapped_cfg;
98 static __iomem void *ltq_pci_membase;
99 
100 int (*ltqpci_plat_dev_init)(struct pci_dev *dev) = NULL;
101 
102 /* Since the PCI REQ pins can be reused for other functionality, make it
103    possible to exclude those from interpretation by the PCI controller */
104 static int ltq_pci_req_mask = 0xf;
105 
106 static int *ltq_pci_irq_map;
107 
108 struct pci_ops ltq_pci_ops = {
109 	.read	= ltq_pci_read_config_dword,
110 	.write	= ltq_pci_write_config_dword
111 };
112 
113 static struct resource pci_io_resource = {
114 	.name	= "pci io space",
115 	.start	= LTQ_PCI_IO_BASE,
116 	.end	= LTQ_PCI_IO_BASE + LTQ_PCI_IO_SIZE - 1,
117 	.flags	= IORESOURCE_IO
118 };
119 
120 static struct resource pci_mem_resource = {
121 	.name	= "pci memory space",
122 	.start	= LTQ_PCI_MEM_BASE,
123 	.end	= LTQ_PCI_MEM_BASE + LTQ_PCI_MEM_SIZE - 1,
124 	.flags	= IORESOURCE_MEM
125 };
126 
127 static struct pci_controller ltq_pci_controller = {
128 	.pci_ops	= &ltq_pci_ops,
129 	.mem_resource	= &pci_mem_resource,
130 	.mem_offset	= 0x00000000UL,
131 	.io_resource	= &pci_io_resource,
132 	.io_offset	= 0x00000000UL,
133 };
134 
pcibios_plat_dev_init(struct pci_dev * dev)135 int pcibios_plat_dev_init(struct pci_dev *dev)
136 {
137 	if (ltqpci_plat_dev_init)
138 		return ltqpci_plat_dev_init(dev);
139 
140 	return 0;
141 }
142 
ltq_calc_bar11mask(void)143 static u32 ltq_calc_bar11mask(void)
144 {
145 	u32 mem, bar11mask;
146 
147 	/* BAR11MASK value depends on available memory on system. */
148 	mem = num_physpages * PAGE_SIZE;
149 	bar11mask = (0x0ffffff0 & ~((1 << (fls(mem) - 1)) - 1)) | 8;
150 
151 	return bar11mask;
152 }
153 
ltq_pci_setup_gpio(int gpio)154 static void ltq_pci_setup_gpio(int gpio)
155 {
156 	int i;
157 	for (i = 0; i < ARRAY_SIZE(ltq_pci_gpio_map); i++) {
158 		if (gpio & (1 << i)) {
159 			ltq_gpio_request(ltq_pci_gpio_map[i].pin,
160 				ltq_pci_gpio_map[i].alt0,
161 				ltq_pci_gpio_map[i].alt1,
162 				ltq_pci_gpio_map[i].dir,
163 				ltq_pci_gpio_map[i].name);
164 		}
165 	}
166 	ltq_gpio_request(21, 0, 0, 1, "pci-reset");
167 	ltq_pci_req_mask = (gpio >> PCI_REQ_SHIFT) & PCI_REQ_MASK;
168 }
169 
ltq_pci_startup(struct ltq_pci_data * conf)170 static int __devinit ltq_pci_startup(struct ltq_pci_data *conf)
171 {
172 	u32 temp_buffer;
173 
174 	/* set clock to 33Mhz */
175 	if (ltq_is_ar9()) {
176 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) & ~0x1f00000, LTQ_CGU_IFCCR);
177 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) | 0xe00000, LTQ_CGU_IFCCR);
178 	} else {
179 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) & ~0xf00000, LTQ_CGU_IFCCR);
180 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) | 0x800000, LTQ_CGU_IFCCR);
181 	}
182 
183 	/* external or internal clock ? */
184 	if (conf->clock) {
185 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) & ~(1 << 16),
186 			LTQ_CGU_IFCCR);
187 		ltq_cgu_w32((1 << 30), LTQ_CGU_PCICR);
188 	} else {
189 		ltq_cgu_w32(ltq_cgu_r32(LTQ_CGU_IFCCR) | (1 << 16),
190 			LTQ_CGU_IFCCR);
191 		ltq_cgu_w32((1 << 31) | (1 << 30), LTQ_CGU_PCICR);
192 	}
193 
194 	/* setup pci clock and gpis used by pci */
195 	ltq_pci_setup_gpio(conf->gpio);
196 
197 	/* enable auto-switching between PCI and EBU */
198 	ltq_pci_w32(0xa, PCI_CR_CLK_CTRL);
199 
200 	/* busy, i.e. configuration is not done, PCI access has to be retried */
201 	ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) & ~(1 << 24), PCI_CR_PCI_MOD);
202 	wmb();
203 	/* BUS Master/IO/MEM access */
204 	ltq_pci_cfg_w32(ltq_pci_cfg_r32(PCI_CS_STS_CMD) | 7, PCI_CS_STS_CMD);
205 
206 	/* enable external 2 PCI masters */
207 	temp_buffer = ltq_pci_r32(PCI_CR_PC_ARB);
208 	temp_buffer &= (~(ltq_pci_req_mask << 16));
209 	/* enable internal arbiter */
210 	temp_buffer |= (1 << INTERNAL_ARB_ENABLE_BIT);
211 	/* enable internal PCI master reqest */
212 	temp_buffer &= (~(3 << PCI_MASTER0_REQ_MASK_2BITS));
213 
214 	/* enable EBU request */
215 	temp_buffer &= (~(3 << PCI_MASTER1_REQ_MASK_2BITS));
216 
217 	/* enable all external masters request */
218 	temp_buffer &= (~(3 << PCI_MASTER2_REQ_MASK_2BITS));
219 	ltq_pci_w32(temp_buffer, PCI_CR_PC_ARB);
220 	wmb();
221 
222 	/* setup BAR memory regions */
223 	ltq_pci_w32(0x18000000, PCI_CR_FCI_ADDR_MAP0);
224 	ltq_pci_w32(0x18400000, PCI_CR_FCI_ADDR_MAP1);
225 	ltq_pci_w32(0x18800000, PCI_CR_FCI_ADDR_MAP2);
226 	ltq_pci_w32(0x18c00000, PCI_CR_FCI_ADDR_MAP3);
227 	ltq_pci_w32(0x19000000, PCI_CR_FCI_ADDR_MAP4);
228 	ltq_pci_w32(0x19400000, PCI_CR_FCI_ADDR_MAP5);
229 	ltq_pci_w32(0x19800000, PCI_CR_FCI_ADDR_MAP6);
230 	ltq_pci_w32(0x19c00000, PCI_CR_FCI_ADDR_MAP7);
231 	ltq_pci_w32(0x1ae00000, PCI_CR_FCI_ADDR_MAP11hg);
232 	ltq_pci_w32(ltq_calc_bar11mask(), PCI_CR_BAR11MASK);
233 	ltq_pci_w32(0, PCI_CR_PCI_ADDR_MAP11);
234 	ltq_pci_w32(0, PCI_CS_BASE_ADDR1);
235 	/* both TX and RX endian swap are enabled */
236 	ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_EOI) | 3, PCI_CR_PCI_EOI);
237 	wmb();
238 	ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR12MASK) | 0x80000000,
239 		PCI_CR_BAR12MASK);
240 	ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR13MASK) | 0x80000000,
241 		PCI_CR_BAR13MASK);
242 	/*use 8 dw burst length */
243 	ltq_pci_w32(0x303, PCI_CR_FCI_BURST_LENGTH);
244 	ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) | (1 << 24), PCI_CR_PCI_MOD);
245 	wmb();
246 
247 	/* setup irq line */
248 	ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_CON) | 0xc, LTQ_EBU_PCC_CON);
249 	ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_IEN) | 0x10, LTQ_EBU_PCC_IEN);
250 
251 	/* toggle reset pin */
252 	__gpio_set_value(21, 0);
253 	wmb();
254 	mdelay(1);
255 	__gpio_set_value(21, 1);
256 	return 0;
257 }
258 
pcibios_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)259 int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
260 {
261 	if (ltq_pci_irq_map[slot])
262 		return ltq_pci_irq_map[slot];
263 	printk(KERN_ERR "lq_pci: trying to map irq for unknown slot %d\n",
264 		slot);
265 
266 	return 0;
267 }
268 
ltq_pci_probe(struct platform_device * pdev)269 static int __devinit ltq_pci_probe(struct platform_device *pdev)
270 {
271 	struct ltq_pci_data *ltq_pci_data =
272 		(struct ltq_pci_data *) pdev->dev.platform_data;
273 
274 	pci_clear_flags(PCI_PROBE_ONLY);
275 	ltq_pci_irq_map = ltq_pci_data->irq;
276 	ltq_pci_membase = ioremap_nocache(PCI_CR_BASE_ADDR, PCI_CR_SIZE);
277 	ltq_pci_mapped_cfg =
278 		ioremap_nocache(LTQ_PCI_CFG_BASE, LTQ_PCI_CFG_BASE);
279 	ltq_pci_controller.io_map_base =
280 		(unsigned long)ioremap(LTQ_PCI_IO_BASE, LTQ_PCI_IO_SIZE - 1);
281 	ltq_pci_startup(ltq_pci_data);
282 	register_pci_controller(&ltq_pci_controller);
283 
284 	return 0;
285 }
286 
287 static struct platform_driver
288 ltq_pci_driver = {
289 	.probe = ltq_pci_probe,
290 	.driver = {
291 		.name = "ltq_pci",
292 		.owner = THIS_MODULE,
293 	},
294 };
295 
pcibios_init(void)296 int __init pcibios_init(void)
297 {
298 	int ret = platform_driver_register(&ltq_pci_driver);
299 	if (ret)
300 		printk(KERN_INFO "ltq_pci: Error registering platfom driver!");
301 	return ret;
302 }
303 
304 arch_initcall(pcibios_init);
305