1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Rockchip AXI PCIe host controller driver
4  *
5  * Copyright (c) 2016 Rockchip, Inc.
6  *
7  * Author: Shawn Lin <shawn.lin@rock-chips.com>
8  *         Wenrui Li <wenrui.li@rock-chips.com>
9  *
10  * Bits taken from Synopsys DesignWare Host controller driver and
11  * ARM PCI Host generic driver.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/iopoll.h>
18 #include <linux/of.h>
19 #include <linux/of_pci.h>
20 #include <linux/phy/phy.h>
21 #include <linux/platform_device.h>
22 #include <linux/reset.h>
23 
24 #include "../pci.h"
25 #include "pcie-rockchip.h"
26 
27 int rockchip_pcie_parse_dt(struct rockchip_pcie *rockchip)
28 {
29 	struct device *dev = rockchip->dev;
30 	struct platform_device *pdev = to_platform_device(dev);
31 	struct device_node *node = dev->of_node;
32 	struct resource *regs;
33 	int err, i;
34 
35 	if (rockchip->is_rc) {
36 		regs = platform_get_resource_byname(pdev,
37 						    IORESOURCE_MEM,
38 						    "axi-base");
39 		rockchip->reg_base = devm_pci_remap_cfg_resource(dev, regs);
40 		if (IS_ERR(rockchip->reg_base))
41 			return PTR_ERR(rockchip->reg_base);
42 	} else {
43 		rockchip->mem_res =
44 			platform_get_resource_byname(pdev, IORESOURCE_MEM,
45 						     "mem-base");
46 		if (!rockchip->mem_res)
47 			return -EINVAL;
48 	}
49 
50 	rockchip->apb_base =
51 		devm_platform_ioremap_resource_byname(pdev, "apb-base");
52 	if (IS_ERR(rockchip->apb_base))
53 		return PTR_ERR(rockchip->apb_base);
54 
55 	err = rockchip_pcie_get_phys(rockchip);
56 	if (err)
57 		return err;
58 
59 	rockchip->lanes = 1;
60 	err = of_property_read_u32(node, "num-lanes", &rockchip->lanes);
61 	if (!err && (rockchip->lanes == 0 ||
62 		     rockchip->lanes == 3 ||
63 		     rockchip->lanes > 4)) {
64 		dev_warn(dev, "invalid num-lanes, default to use one lane\n");
65 		rockchip->lanes = 1;
66 	}
67 
68 	rockchip->link_gen = of_pci_get_max_link_speed(node);
69 	if (rockchip->link_gen < 0 || rockchip->link_gen > 2)
70 		rockchip->link_gen = 2;
71 
72 	for (i = 0; i < ROCKCHIP_NUM_PM_RSTS; i++)
73 		rockchip->pm_rsts[i].id = rockchip_pci_pm_rsts[i];
74 
75 	err = devm_reset_control_bulk_get_exclusive(dev,
76 						    ROCKCHIP_NUM_PM_RSTS,
77 						    rockchip->pm_rsts);
78 	if (err)
79 		return dev_err_probe(dev, err, "Cannot get the PM reset\n");
80 
81 	for (i = 0; i < ROCKCHIP_NUM_CORE_RSTS; i++)
82 		rockchip->core_rsts[i].id = rockchip_pci_core_rsts[i];
83 
84 	err = devm_reset_control_bulk_get_exclusive(dev,
85 						    ROCKCHIP_NUM_CORE_RSTS,
86 						    rockchip->core_rsts);
87 	if (err)
88 		return dev_err_probe(dev, err, "Cannot get the Core resets\n");
89 
90 	if (rockchip->is_rc)
91 		rockchip->perst_gpio = devm_gpiod_get_optional(dev, "ep",
92 							       GPIOD_OUT_LOW);
93 	else
94 		rockchip->perst_gpio = devm_gpiod_get_optional(dev, "reset",
95 							       GPIOD_IN);
96 	if (IS_ERR(rockchip->perst_gpio))
97 		return dev_err_probe(dev, PTR_ERR(rockchip->perst_gpio),
98 				     "failed to get PERST# GPIO\n");
99 
100 	rockchip->num_clks = devm_clk_bulk_get_all(dev, &rockchip->clks);
101 	if (rockchip->num_clks < 0)
102 		return dev_err_probe(dev, rockchip->num_clks,
103 				     "failed to get clocks\n");
104 
105 	return 0;
106 }
107 EXPORT_SYMBOL_GPL(rockchip_pcie_parse_dt);
108 
109 #define rockchip_pcie_read_addr(addr) rockchip_pcie_read(rockchip, addr)
110 /* 100 ms max wait time for PHY PLLs to lock */
111 #define RK_PHY_PLL_LOCK_TIMEOUT_US 100000
112 /* Sleep should be less than 20ms */
113 #define RK_PHY_PLL_LOCK_SLEEP_US 1000
114 
115 int rockchip_pcie_init_port(struct rockchip_pcie *rockchip)
116 {
117 	struct device *dev = rockchip->dev;
118 	int err, i;
119 	u32 regs;
120 
121 	err = reset_control_bulk_assert(ROCKCHIP_NUM_PM_RSTS,
122 					rockchip->pm_rsts);
123 	if (err)
124 		return dev_err_probe(dev, err, "Couldn't assert PM resets\n");
125 
126 	for (i = 0; i < MAX_LANE_NUM; i++) {
127 		err = phy_init(rockchip->phys[i]);
128 		if (err) {
129 			dev_err(dev, "init phy%d err %d\n", i, err);
130 			goto err_exit_phy;
131 		}
132 	}
133 
134 	err = reset_control_bulk_assert(ROCKCHIP_NUM_CORE_RSTS,
135 					rockchip->core_rsts);
136 	if (err) {
137 		dev_err_probe(dev, err, "Couldn't assert Core resets\n");
138 		goto err_exit_phy;
139 	}
140 
141 	udelay(10);
142 
143 	err = reset_control_bulk_deassert(ROCKCHIP_NUM_PM_RSTS,
144 					  rockchip->pm_rsts);
145 	if (err) {
146 		dev_err(dev, "Couldn't deassert PM resets %d\n", err);
147 		goto err_exit_phy;
148 	}
149 
150 	if (rockchip->link_gen == 2)
151 		rockchip_pcie_write(rockchip, PCIE_CLIENT_GEN_SEL_2,
152 				    PCIE_CLIENT_CONFIG);
153 	else
154 		rockchip_pcie_write(rockchip, PCIE_CLIENT_GEN_SEL_1,
155 				    PCIE_CLIENT_CONFIG);
156 
157 	regs = PCIE_CLIENT_ARI_ENABLE |
158 	       PCIE_CLIENT_CONF_LANE_NUM(rockchip->lanes);
159 
160 	if (rockchip->is_rc)
161 		regs |= PCIE_CLIENT_LINK_TRAIN_ENABLE |
162 			PCIE_CLIENT_CONF_ENABLE | PCIE_CLIENT_MODE_RC;
163 	else
164 		regs |= PCIE_CLIENT_CONF_DISABLE | PCIE_CLIENT_MODE_EP;
165 
166 	rockchip_pcie_write(rockchip, regs, PCIE_CLIENT_CONFIG);
167 
168 	for (i = 0; i < MAX_LANE_NUM; i++) {
169 		err = phy_power_on(rockchip->phys[i]);
170 		if (err) {
171 			dev_err(dev, "power on phy%d err %d\n", i, err);
172 			goto err_power_off_phy;
173 		}
174 	}
175 
176 	err = readx_poll_timeout(rockchip_pcie_read_addr,
177 				 PCIE_CLIENT_SIDE_BAND_STATUS,
178 				 regs, !(regs & PCIE_CLIENT_PHY_ST),
179 				 RK_PHY_PLL_LOCK_SLEEP_US,
180 				 RK_PHY_PLL_LOCK_TIMEOUT_US);
181 	if (err) {
182 		dev_err(dev, "PHY PLLs could not lock, %d\n", err);
183 		goto err_power_off_phy;
184 	}
185 
186 	err = reset_control_bulk_deassert(ROCKCHIP_NUM_CORE_RSTS,
187 					  rockchip->core_rsts);
188 	if (err) {
189 		dev_err(dev, "Couldn't deassert Core reset %d\n", err);
190 		goto err_power_off_phy;
191 	}
192 
193 	return 0;
194 err_power_off_phy:
195 	while (i--)
196 		phy_power_off(rockchip->phys[i]);
197 	i = MAX_LANE_NUM;
198 err_exit_phy:
199 	while (i--)
200 		phy_exit(rockchip->phys[i]);
201 	return err;
202 }
203 EXPORT_SYMBOL_GPL(rockchip_pcie_init_port);
204 
205 int rockchip_pcie_get_phys(struct rockchip_pcie *rockchip)
206 {
207 	struct device *dev = rockchip->dev;
208 	struct phy *phy;
209 	char *name;
210 	u32 i;
211 
212 	phy = devm_phy_get(dev, "pcie-phy");
213 	if (!IS_ERR(phy)) {
214 		rockchip->legacy_phy = true;
215 		rockchip->phys[0] = phy;
216 		dev_warn(dev, "legacy phy model is deprecated!\n");
217 		return 0;
218 	}
219 
220 	if (PTR_ERR(phy) == -EPROBE_DEFER)
221 		return PTR_ERR(phy);
222 
223 	dev_dbg(dev, "missing legacy phy; search for per-lane PHY\n");
224 
225 	for (i = 0; i < MAX_LANE_NUM; i++) {
226 		name = kasprintf(GFP_KERNEL, "pcie-phy-%u", i);
227 		if (!name)
228 			return -ENOMEM;
229 
230 		phy = devm_of_phy_get(dev, dev->of_node, name);
231 		kfree(name);
232 
233 		if (IS_ERR(phy)) {
234 			if (PTR_ERR(phy) != -EPROBE_DEFER)
235 				dev_err(dev, "missing phy for lane %d: %ld\n",
236 					i, PTR_ERR(phy));
237 			return PTR_ERR(phy);
238 		}
239 
240 		rockchip->phys[i] = phy;
241 	}
242 
243 	return 0;
244 }
245 EXPORT_SYMBOL_GPL(rockchip_pcie_get_phys);
246 
247 void rockchip_pcie_deinit_phys(struct rockchip_pcie *rockchip)
248 {
249 	int i;
250 
251 	for (i = 0; i < MAX_LANE_NUM; i++) {
252 		/* inactive lanes are already powered off */
253 		if (rockchip->lanes_map & BIT(i))
254 			phy_power_off(rockchip->phys[i]);
255 		phy_exit(rockchip->phys[i]);
256 	}
257 }
258 EXPORT_SYMBOL_GPL(rockchip_pcie_deinit_phys);
259 
260 int rockchip_pcie_enable_clocks(struct rockchip_pcie *rockchip)
261 {
262 	struct device *dev = rockchip->dev;
263 	int err;
264 
265 	err = clk_bulk_prepare_enable(rockchip->num_clks, rockchip->clks);
266 	if (err)
267 		return dev_err_probe(dev, err, "failed to enable clocks\n");
268 
269 	return 0;
270 }
271 EXPORT_SYMBOL_GPL(rockchip_pcie_enable_clocks);
272 
273 void rockchip_pcie_disable_clocks(struct rockchip_pcie *rockchip)
274 {
275 
276 	clk_bulk_disable_unprepare(rockchip->num_clks, rockchip->clks);
277 }
278 EXPORT_SYMBOL_GPL(rockchip_pcie_disable_clocks);
279 
280 void rockchip_pcie_cfg_configuration_accesses(
281 		struct rockchip_pcie *rockchip, u32 type)
282 {
283 	u32 ob_desc_0;
284 
285 	/* Configuration Accesses for region 0 */
286 	rockchip_pcie_write(rockchip, 0x0, PCIE_RC_BAR_CONF);
287 
288 	rockchip_pcie_write(rockchip,
289 			    (RC_REGION_0_ADDR_TRANS_L + RC_REGION_0_PASS_BITS),
290 			    PCIE_CORE_OB_REGION_ADDR0);
291 	rockchip_pcie_write(rockchip, RC_REGION_0_ADDR_TRANS_H,
292 			    PCIE_CORE_OB_REGION_ADDR1);
293 	ob_desc_0 = rockchip_pcie_read(rockchip, PCIE_CORE_OB_REGION_DESC0);
294 	ob_desc_0 &= ~(RC_REGION_0_TYPE_MASK);
295 	ob_desc_0 |= (type | (0x1 << 23));
296 	rockchip_pcie_write(rockchip, ob_desc_0, PCIE_CORE_OB_REGION_DESC0);
297 	rockchip_pcie_write(rockchip, 0x0, PCIE_CORE_OB_REGION_DESC1);
298 }
299 EXPORT_SYMBOL_GPL(rockchip_pcie_cfg_configuration_accesses);
300