1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 *
4 * Copyright (C) 2010 John Crispin <john@phrozen.org>
5 */
6
7 #include <linux/types.h>
8 #include <linux/pci.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/delay.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/mm.h>
14 #include <linux/vmalloc.h>
15 #include <linux/clk.h>
16 #include <linux/of.h>
17 #include <linux/of_pci.h>
18 #include <linux/platform_device.h>
19
20 #include <asm/addrspace.h>
21
22 #include <lantiq_soc.h>
23 #include <lantiq_irq.h>
24
25 #include "pci-lantiq.h"
26
27 #define PCI_CR_FCI_ADDR_MAP0 0x00C0
28 #define PCI_CR_FCI_ADDR_MAP1 0x00C4
29 #define PCI_CR_FCI_ADDR_MAP2 0x00C8
30 #define PCI_CR_FCI_ADDR_MAP3 0x00CC
31 #define PCI_CR_FCI_ADDR_MAP4 0x00D0
32 #define PCI_CR_FCI_ADDR_MAP5 0x00D4
33 #define PCI_CR_FCI_ADDR_MAP6 0x00D8
34 #define PCI_CR_FCI_ADDR_MAP7 0x00DC
35 #define PCI_CR_CLK_CTRL 0x0000
36 #define PCI_CR_PCI_MOD 0x0030
37 #define PCI_CR_PC_ARB 0x0080
38 #define PCI_CR_FCI_ADDR_MAP11hg 0x00E4
39 #define PCI_CR_BAR11MASK 0x0044
40 #define PCI_CR_BAR12MASK 0x0048
41 #define PCI_CR_BAR13MASK 0x004C
42 #define PCI_CS_BASE_ADDR1 0x0010
43 #define PCI_CR_PCI_ADDR_MAP11 0x0064
44 #define PCI_CR_FCI_BURST_LENGTH 0x00E8
45 #define PCI_CR_PCI_EOI 0x002C
46 #define PCI_CS_STS_CMD 0x0004
47
48 #define PCI_MASTER0_REQ_MASK_2BITS 8
49 #define PCI_MASTER1_REQ_MASK_2BITS 10
50 #define PCI_MASTER2_REQ_MASK_2BITS 12
51 #define INTERNAL_ARB_ENABLE_BIT 0
52
53 #define LTQ_CGU_IFCCR 0x0018
54 #define LTQ_CGU_PCICR 0x0034
55
56 #define ltq_pci_w32(x, y) ltq_w32((x), ltq_pci_membase + (y))
57 #define ltq_pci_r32(x) ltq_r32(ltq_pci_membase + (x))
58
59 #define ltq_pci_cfg_w32(x, y) ltq_w32((x), ltq_pci_mapped_cfg + (y))
60 #define ltq_pci_cfg_r32(x) ltq_r32(ltq_pci_mapped_cfg + (x))
61
62 __iomem void *ltq_pci_mapped_cfg;
63 static __iomem void *ltq_pci_membase;
64
65 static struct gpio_desc *reset_gpio;
66 static struct clk *clk_pci, *clk_external;
67 static struct resource pci_io_resource;
68 static struct resource pci_mem_resource;
69 static struct pci_ops pci_ops = {
70 .read = ltq_pci_read_config_dword,
71 .write = ltq_pci_write_config_dword
72 };
73
74 static struct pci_controller pci_controller = {
75 .pci_ops = &pci_ops,
76 .mem_resource = &pci_mem_resource,
77 .mem_offset = 0x00000000UL,
78 .io_resource = &pci_io_resource,
79 .io_offset = 0x00000000UL,
80 };
81
82 static inline u32 ltq_calc_bar11mask(void)
83 {
84 u32 mem, bar11mask;
85
86 /* BAR11MASK value depends on available memory on system. */
87 mem = get_num_physpages() * PAGE_SIZE;
88 bar11mask = (0x0ffffff0 & ~((1 << (fls(mem) - 1)) - 1)) | 8;
89
90 return bar11mask;
91 }
92
93 static int ltq_pci_startup(struct platform_device *pdev)
94 {
95 struct device_node *node = pdev->dev.of_node;
96 const __be32 *req_mask, *bus_clk;
97 u32 temp_buffer;
98 int error;
99
100 /* get our clocks */
101 clk_pci = clk_get(&pdev->dev, NULL);
102 if (IS_ERR(clk_pci)) {
103 dev_err(&pdev->dev, "failed to get pci clock\n");
104 return PTR_ERR(clk_pci);
105 }
106
107 clk_external = clk_get(&pdev->dev, "external");
108 if (IS_ERR(clk_external)) {
109 clk_put(clk_pci);
110 dev_err(&pdev->dev, "failed to get external pci clock\n");
111 return PTR_ERR(clk_external);
112 }
113
114 /* read the bus speed that we want */
115 bus_clk = of_get_property(node, "lantiq,bus-clock", NULL);
116 if (bus_clk)
117 clk_set_rate(clk_pci, *bus_clk);
118
119 /* and enable the clocks */
120 clk_enable(clk_pci);
121 if (of_property_read_bool(node, "lantiq,external-clock"))
122 clk_enable(clk_external);
123 else
124 clk_disable(clk_external);
125
126 /* setup reset gpio used by pci */
127 reset_gpio = devm_gpiod_get_optional(&pdev->dev, "reset",
128 GPIOD_OUT_LOW);
129 error = PTR_ERR_OR_ZERO(reset_gpio);
130 if (error) {
131 dev_err(&pdev->dev, "failed to request gpio: %d\n", error);
132 return error;
133 }
134 gpiod_set_consumer_name(reset_gpio, "pci_reset");
135
136 /* enable auto-switching between PCI and EBU */
137 ltq_pci_w32(0xa, PCI_CR_CLK_CTRL);
138
139 /* busy, i.e. configuration is not done, PCI access has to be retried */
140 ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) & ~(1 << 24), PCI_CR_PCI_MOD);
141 wmb();
142 /* BUS Master/IO/MEM access */
143 ltq_pci_cfg_w32(ltq_pci_cfg_r32(PCI_CS_STS_CMD) | 7, PCI_CS_STS_CMD);
144
145 /* enable external 2 PCI masters */
146 temp_buffer = ltq_pci_r32(PCI_CR_PC_ARB);
147 /* setup the request mask */
148 req_mask = of_get_property(node, "req-mask", NULL);
149 if (req_mask)
150 temp_buffer &= ~((*req_mask & 0xf) << 16);
151 else
152 temp_buffer &= ~0xf0000;
153 /* enable internal arbiter */
154 temp_buffer |= (1 << INTERNAL_ARB_ENABLE_BIT);
155 /* enable internal PCI master request */
156 temp_buffer &= (~(3 << PCI_MASTER0_REQ_MASK_2BITS));
157
158 /* enable EBU request */
159 temp_buffer &= (~(3 << PCI_MASTER1_REQ_MASK_2BITS));
160
161 /* enable all external masters request */
162 temp_buffer &= (~(3 << PCI_MASTER2_REQ_MASK_2BITS));
163 ltq_pci_w32(temp_buffer, PCI_CR_PC_ARB);
164 wmb();
165
166 /* setup BAR memory regions */
167 ltq_pci_w32(0x18000000, PCI_CR_FCI_ADDR_MAP0);
168 ltq_pci_w32(0x18400000, PCI_CR_FCI_ADDR_MAP1);
169 ltq_pci_w32(0x18800000, PCI_CR_FCI_ADDR_MAP2);
170 ltq_pci_w32(0x18c00000, PCI_CR_FCI_ADDR_MAP3);
171 ltq_pci_w32(0x19000000, PCI_CR_FCI_ADDR_MAP4);
172 ltq_pci_w32(0x19400000, PCI_CR_FCI_ADDR_MAP5);
173 ltq_pci_w32(0x19800000, PCI_CR_FCI_ADDR_MAP6);
174 ltq_pci_w32(0x19c00000, PCI_CR_FCI_ADDR_MAP7);
175 ltq_pci_w32(0x1ae00000, PCI_CR_FCI_ADDR_MAP11hg);
176 ltq_pci_w32(ltq_calc_bar11mask(), PCI_CR_BAR11MASK);
177 ltq_pci_w32(0, PCI_CR_PCI_ADDR_MAP11);
178 ltq_pci_w32(0, PCI_CS_BASE_ADDR1);
179 /* both TX and RX endian swap are enabled */
180 ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_EOI) | 3, PCI_CR_PCI_EOI);
181 wmb();
182 ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR12MASK) | 0x80000000,
183 PCI_CR_BAR12MASK);
184 ltq_pci_w32(ltq_pci_r32(PCI_CR_BAR13MASK) | 0x80000000,
185 PCI_CR_BAR13MASK);
186 /*use 8 dw burst length */
187 ltq_pci_w32(0x303, PCI_CR_FCI_BURST_LENGTH);
188 ltq_pci_w32(ltq_pci_r32(PCI_CR_PCI_MOD) | (1 << 24), PCI_CR_PCI_MOD);
189 wmb();
190
191 /* setup irq line */
192 ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_CON) | 0xc, LTQ_EBU_PCC_CON);
193 ltq_ebu_w32(ltq_ebu_r32(LTQ_EBU_PCC_IEN) | 0x10, LTQ_EBU_PCC_IEN);
194
195 /* toggle reset pin */
196 if (reset_gpio) {
197 gpiod_set_value_cansleep(reset_gpio, 1);
198 wmb();
199 mdelay(1);
200 gpiod_set_value_cansleep(reset_gpio, 0);
201 }
202 return 0;
203 }
204
205 static int ltq_pci_probe(struct platform_device *pdev)
206 {
207 pci_clear_flags(PCI_PROBE_ONLY);
208
209 ltq_pci_membase = devm_platform_get_and_ioremap_resource(pdev, 1, NULL);
210 if (IS_ERR(ltq_pci_membase))
211 return PTR_ERR(ltq_pci_membase);
212
213 ltq_pci_mapped_cfg = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
214 if (IS_ERR(ltq_pci_mapped_cfg))
215 return PTR_ERR(ltq_pci_mapped_cfg);
216
217 ltq_pci_startup(pdev);
218
219 pci_load_of_ranges(&pci_controller, pdev->dev.of_node);
220 register_pci_controller(&pci_controller);
221 return 0;
222 }
223
224 static const struct of_device_id ltq_pci_match[] = {
225 { .compatible = "lantiq,pci-xway" },
226 {},
227 };
228
229 static struct platform_driver ltq_pci_driver = {
230 .probe = ltq_pci_probe,
231 .driver = {
232 .name = "pci-xway",
233 .of_match_table = ltq_pci_match,
234 },
235 };
236
237 int __init pcibios_init(void)
238 {
239 int ret = platform_driver_register(<q_pci_driver);
240 if (ret)
241 pr_info("pci-xway: Error registering platform driver!");
242 return ret;
243 }
244
245 arch_initcall(pcibios_init);
246
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