1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017 Cadence
3 // Cadence PCIe controller driver.
4 // Author: Cyrille Pitchen <cyrille.pitchen@free-electrons.com>
5 
6 #include <linux/kernel.h>
7 
8 #include "pcie-cadence.h"
9 
cdns_pcie_set_outbound_region(struct cdns_pcie * pcie,u8 fn,u32 r,bool is_io,u64 cpu_addr,u64 pci_addr,size_t size)10 void cdns_pcie_set_outbound_region(struct cdns_pcie *pcie, u8 fn,
11 				   u32 r, bool is_io,
12 				   u64 cpu_addr, u64 pci_addr, size_t size)
13 {
14 	/*
15 	 * roundup_pow_of_two() returns an unsigned long, which is not suited
16 	 * for 64bit values.
17 	 */
18 	u64 sz = 1ULL << fls64(size - 1);
19 	int nbits = ilog2(sz);
20 	u32 addr0, addr1, desc0, desc1;
21 
22 	if (nbits < 8)
23 		nbits = 8;
24 
25 	/* Set the PCI address */
26 	addr0 = CDNS_PCIE_AT_OB_REGION_PCI_ADDR0_NBITS(nbits) |
27 		(lower_32_bits(pci_addr) & GENMASK(31, 8));
28 	addr1 = upper_32_bits(pci_addr);
29 
30 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), addr0);
31 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), addr1);
32 
33 	/* Set the PCIe header descriptor */
34 	if (is_io)
35 		desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_IO;
36 	else
37 		desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_MEM;
38 	desc1 = 0;
39 
40 	/*
41 	 * Whatever Bit [23] is set or not inside DESC0 register of the outbound
42 	 * PCIe descriptor, the PCI function number must be set into
43 	 * Bits [26:24] of DESC0 anyway.
44 	 *
45 	 * In Root Complex mode, the function number is always 0 but in Endpoint
46 	 * mode, the PCIe controller may support more than one function. This
47 	 * function number needs to be set properly into the outbound PCIe
48 	 * descriptor.
49 	 *
50 	 * Besides, setting Bit [23] is mandatory when in Root Complex mode:
51 	 * then the driver must provide the bus, resp. device, number in
52 	 * Bits [7:0] of DESC1, resp. Bits[31:27] of DESC0. Like the function
53 	 * number, the device number is always 0 in Root Complex mode.
54 	 *
55 	 * However when in Endpoint mode, we can clear Bit [23] of DESC0, hence
56 	 * the PCIe controller will use the captured values for the bus and
57 	 * device numbers.
58 	 */
59 	if (pcie->is_rc) {
60 		/* The device and function numbers are always 0. */
61 		desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID |
62 			 CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0);
63 		desc1 |= CDNS_PCIE_AT_OB_REGION_DESC1_BUS(pcie->bus);
64 	} else {
65 		/*
66 		 * Use captured values for bus and device numbers but still
67 		 * need to set the function number.
68 		 */
69 		desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(fn);
70 	}
71 
72 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), desc0);
73 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), desc1);
74 
75 	/* Set the CPU address */
76 	cpu_addr -= pcie->mem_res->start;
77 	addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(nbits) |
78 		(lower_32_bits(cpu_addr) & GENMASK(31, 8));
79 	addr1 = upper_32_bits(cpu_addr);
80 
81 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), addr0);
82 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), addr1);
83 }
84 
cdns_pcie_set_outbound_region_for_normal_msg(struct cdns_pcie * pcie,u8 fn,u32 r,u64 cpu_addr)85 void cdns_pcie_set_outbound_region_for_normal_msg(struct cdns_pcie *pcie, u8 fn,
86 						  u32 r, u64 cpu_addr)
87 {
88 	u32 addr0, addr1, desc0, desc1;
89 
90 	desc0 = CDNS_PCIE_AT_OB_REGION_DESC0_TYPE_NORMAL_MSG;
91 	desc1 = 0;
92 
93 	/* See cdns_pcie_set_outbound_region() comments above. */
94 	if (pcie->is_rc) {
95 		desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_HARDCODED_RID |
96 			 CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(0);
97 		desc1 |= CDNS_PCIE_AT_OB_REGION_DESC1_BUS(pcie->bus);
98 	} else {
99 		desc0 |= CDNS_PCIE_AT_OB_REGION_DESC0_DEVFN(fn);
100 	}
101 
102 	/* Set the CPU address */
103 	cpu_addr -= pcie->mem_res->start;
104 	addr0 = CDNS_PCIE_AT_OB_REGION_CPU_ADDR0_NBITS(17) |
105 		(lower_32_bits(cpu_addr) & GENMASK(31, 8));
106 	addr1 = upper_32_bits(cpu_addr);
107 
108 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), 0);
109 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), 0);
110 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), desc0);
111 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), desc1);
112 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), addr0);
113 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), addr1);
114 }
115 
cdns_pcie_reset_outbound_region(struct cdns_pcie * pcie,u32 r)116 void cdns_pcie_reset_outbound_region(struct cdns_pcie *pcie, u32 r)
117 {
118 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR0(r), 0);
119 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_PCI_ADDR1(r), 0);
120 
121 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC0(r), 0);
122 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_DESC1(r), 0);
123 
124 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR0(r), 0);
125 	cdns_pcie_writel(pcie, CDNS_PCIE_AT_OB_REGION_CPU_ADDR1(r), 0);
126 }
127 
cdns_pcie_disable_phy(struct cdns_pcie * pcie)128 void cdns_pcie_disable_phy(struct cdns_pcie *pcie)
129 {
130 	int i = pcie->phy_count;
131 
132 	while (i--) {
133 		phy_power_off(pcie->phy[i]);
134 		phy_exit(pcie->phy[i]);
135 	}
136 }
137 
cdns_pcie_enable_phy(struct cdns_pcie * pcie)138 int cdns_pcie_enable_phy(struct cdns_pcie *pcie)
139 {
140 	int ret;
141 	int i;
142 
143 	for (i = 0; i < pcie->phy_count; i++) {
144 		ret = phy_init(pcie->phy[i]);
145 		if (ret < 0)
146 			goto err_phy;
147 
148 		ret = phy_power_on(pcie->phy[i]);
149 		if (ret < 0) {
150 			phy_exit(pcie->phy[i]);
151 			goto err_phy;
152 		}
153 	}
154 
155 	return 0;
156 
157 err_phy:
158 	while (--i >= 0) {
159 		phy_power_off(pcie->phy[i]);
160 		phy_exit(pcie->phy[i]);
161 	}
162 
163 	return ret;
164 }
165 
cdns_pcie_init_phy(struct device * dev,struct cdns_pcie * pcie)166 int cdns_pcie_init_phy(struct device *dev, struct cdns_pcie *pcie)
167 {
168 	struct device_node *np = dev->of_node;
169 	int phy_count;
170 	struct phy **phy;
171 	struct device_link **link;
172 	int i;
173 	int ret;
174 	const char *name;
175 
176 	phy_count = of_property_count_strings(np, "phy-names");
177 	if (phy_count < 1) {
178 		dev_err(dev, "no phy-names.  PHY will not be initialized\n");
179 		pcie->phy_count = 0;
180 		return 0;
181 	}
182 
183 	phy = devm_kcalloc(dev, phy_count, sizeof(*phy), GFP_KERNEL);
184 	if (!phy)
185 		return -ENOMEM;
186 
187 	link = devm_kcalloc(dev, phy_count, sizeof(*link), GFP_KERNEL);
188 	if (!link)
189 		return -ENOMEM;
190 
191 	for (i = 0; i < phy_count; i++) {
192 		of_property_read_string_index(np, "phy-names", i, &name);
193 		phy[i] = devm_phy_get(dev, name);
194 		if (IS_ERR(phy[i])) {
195 			ret = PTR_ERR(phy[i]);
196 			goto err_phy;
197 		}
198 		link[i] = device_link_add(dev, &phy[i]->dev, DL_FLAG_STATELESS);
199 		if (!link[i]) {
200 			devm_phy_put(dev, phy[i]);
201 			ret = -EINVAL;
202 			goto err_phy;
203 		}
204 	}
205 
206 	pcie->phy_count = phy_count;
207 	pcie->phy = phy;
208 	pcie->link = link;
209 
210 	ret =  cdns_pcie_enable_phy(pcie);
211 	if (ret)
212 		goto err_phy;
213 
214 	return 0;
215 
216 err_phy:
217 	while (--i >= 0) {
218 		device_link_del(link[i]);
219 		devm_phy_put(dev, phy[i]);
220 	}
221 
222 	return ret;
223 }
224 
225 #ifdef CONFIG_PM_SLEEP
cdns_pcie_suspend_noirq(struct device * dev)226 static int cdns_pcie_suspend_noirq(struct device *dev)
227 {
228 	struct cdns_pcie *pcie = dev_get_drvdata(dev);
229 
230 	cdns_pcie_disable_phy(pcie);
231 
232 	return 0;
233 }
234 
cdns_pcie_resume_noirq(struct device * dev)235 static int cdns_pcie_resume_noirq(struct device *dev)
236 {
237 	struct cdns_pcie *pcie = dev_get_drvdata(dev);
238 	int ret;
239 
240 	ret = cdns_pcie_enable_phy(pcie);
241 	if (ret) {
242 		dev_err(dev, "failed to enable phy\n");
243 		return ret;
244 	}
245 
246 	return 0;
247 }
248 #endif
249 
250 const struct dev_pm_ops cdns_pcie_pm_ops = {
251 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(cdns_pcie_suspend_noirq,
252 				      cdns_pcie_resume_noirq)
253 };
254