xref: /openbmc/linux/arch/arm/mach-dove/pcie.c (revision 26b32974)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * arch/arm/mach-dove/pcie.c
4  *
5  * PCIe functions for Marvell Dove 88AP510 SoC
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/pci.h>
10 #include <linux/clk.h>
11 #include <video/vga.h>
12 #include <asm/mach/pci.h>
13 #include <asm/mach/arch.h>
14 #include <asm/setup.h>
15 #include <asm/delay.h>
16 #include <plat/pcie.h>
17 #include <plat/addr-map.h>
18 #include "irqs.h"
19 #include "bridge-regs.h"
20 #include "common.h"
21 
22 struct pcie_port {
23 	u8			index;
24 	u8			root_bus_nr;
25 	void __iomem		*base;
26 	spinlock_t		conf_lock;
27 	char			mem_space_name[16];
28 	struct resource		res;
29 };
30 
31 static struct pcie_port pcie_port[2];
32 static int num_pcie_ports;
33 
34 
35 static int __init dove_pcie_setup(int nr, struct pci_sys_data *sys)
36 {
37 	struct pcie_port *pp;
38 	struct resource realio;
39 
40 	if (nr >= num_pcie_ports)
41 		return 0;
42 
43 	pp = &pcie_port[nr];
44 	sys->private_data = pp;
45 	pp->root_bus_nr = sys->busnr;
46 
47 	/*
48 	 * Generic PCIe unit setup.
49 	 */
50 	orion_pcie_set_local_bus_nr(pp->base, sys->busnr);
51 
52 	orion_pcie_setup(pp->base);
53 
54 	realio.start = sys->busnr * SZ_64K;
55 	realio.end = realio.start + SZ_64K - 1;
56 	pci_remap_iospace(&realio, pp->index == 0 ? DOVE_PCIE0_IO_PHYS_BASE :
57 						    DOVE_PCIE1_IO_PHYS_BASE);
58 
59 	/*
60 	 * IORESOURCE_MEM
61 	 */
62 	snprintf(pp->mem_space_name, sizeof(pp->mem_space_name),
63 		 "PCIe %d MEM", pp->index);
64 	pp->mem_space_name[sizeof(pp->mem_space_name) - 1] = 0;
65 	pp->res.name = pp->mem_space_name;
66 	if (pp->index == 0) {
67 		pp->res.start = DOVE_PCIE0_MEM_PHYS_BASE;
68 		pp->res.end = pp->res.start + DOVE_PCIE0_MEM_SIZE - 1;
69 	} else {
70 		pp->res.start = DOVE_PCIE1_MEM_PHYS_BASE;
71 		pp->res.end = pp->res.start + DOVE_PCIE1_MEM_SIZE - 1;
72 	}
73 	pp->res.flags = IORESOURCE_MEM;
74 	if (request_resource(&iomem_resource, &pp->res))
75 		panic("Request PCIe Memory resource failed\n");
76 	pci_add_resource_offset(&sys->resources, &pp->res, sys->mem_offset);
77 
78 	return 1;
79 }
80 
81 static int pcie_valid_config(struct pcie_port *pp, int bus, int dev)
82 {
83 	/*
84 	 * Don't go out when trying to access nonexisting devices
85 	 * on the local bus.
86 	 */
87 	if (bus == pp->root_bus_nr && dev > 1)
88 		return 0;
89 
90 	return 1;
91 }
92 
93 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
94 			int size, u32 *val)
95 {
96 	struct pci_sys_data *sys = bus->sysdata;
97 	struct pcie_port *pp = sys->private_data;
98 	unsigned long flags;
99 	int ret;
100 
101 	if (pcie_valid_config(pp, bus->number, PCI_SLOT(devfn)) == 0) {
102 		*val = 0xffffffff;
103 		return PCIBIOS_DEVICE_NOT_FOUND;
104 	}
105 
106 	spin_lock_irqsave(&pp->conf_lock, flags);
107 	ret = orion_pcie_rd_conf(pp->base, bus, devfn, where, size, val);
108 	spin_unlock_irqrestore(&pp->conf_lock, flags);
109 
110 	return ret;
111 }
112 
113 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
114 			int where, int size, u32 val)
115 {
116 	struct pci_sys_data *sys = bus->sysdata;
117 	struct pcie_port *pp = sys->private_data;
118 	unsigned long flags;
119 	int ret;
120 
121 	if (pcie_valid_config(pp, bus->number, PCI_SLOT(devfn)) == 0)
122 		return PCIBIOS_DEVICE_NOT_FOUND;
123 
124 	spin_lock_irqsave(&pp->conf_lock, flags);
125 	ret = orion_pcie_wr_conf(pp->base, bus, devfn, where, size, val);
126 	spin_unlock_irqrestore(&pp->conf_lock, flags);
127 
128 	return ret;
129 }
130 
131 static struct pci_ops pcie_ops = {
132 	.read = pcie_rd_conf,
133 	.write = pcie_wr_conf,
134 };
135 
136 /*
137  * The root complex has a hardwired class of PCI_CLASS_MEMORY_OTHER, when it
138  * is operating as a root complex this needs to be switched to
139  * PCI_CLASS_BRIDGE_HOST or Linux will errantly try to process the BAR's on
140  * the device. Decoding setup is handled by the orion code.
141  */
142 static void rc_pci_fixup(struct pci_dev *dev)
143 {
144 	if (dev->bus->parent == NULL && dev->devfn == 0) {
145 		struct resource *r;
146 
147 		dev->class &= 0xff;
148 		dev->class |= PCI_CLASS_BRIDGE_HOST << 8;
149 		pci_dev_for_each_resource(dev, r) {
150 			r->start = 0;
151 			r->end   = 0;
152 			r->flags = 0;
153 		}
154 	}
155 }
156 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
157 
158 static int __init
159 dove_pcie_scan_bus(int nr, struct pci_host_bridge *bridge)
160 {
161 	struct pci_sys_data *sys = pci_host_bridge_priv(bridge);
162 
163 	if (nr >= num_pcie_ports) {
164 		BUG();
165 		return -EINVAL;
166 	}
167 
168 	list_splice_init(&sys->resources, &bridge->windows);
169 	bridge->dev.parent = NULL;
170 	bridge->sysdata = sys;
171 	bridge->busnr = sys->busnr;
172 	bridge->ops = &pcie_ops;
173 
174 	return pci_scan_root_bus_bridge(bridge);
175 }
176 
177 static int __init dove_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
178 {
179 	struct pci_sys_data *sys = dev->sysdata;
180 	struct pcie_port *pp = sys->private_data;
181 
182 	return pp->index ? IRQ_DOVE_PCIE1 : IRQ_DOVE_PCIE0;
183 }
184 
185 static struct hw_pci dove_pci __initdata = {
186 	.nr_controllers	= 2,
187 	.setup		= dove_pcie_setup,
188 	.scan		= dove_pcie_scan_bus,
189 	.map_irq	= dove_pcie_map_irq,
190 };
191 
192 static void __init add_pcie_port(int index, void __iomem *base)
193 {
194 	printk(KERN_INFO "Dove PCIe port %d: ", index);
195 
196 	if (orion_pcie_link_up(base)) {
197 		struct pcie_port *pp = &pcie_port[num_pcie_ports++];
198 		struct clk *clk = clk_get_sys("pcie", (index ? "1" : "0"));
199 
200 		if (!IS_ERR(clk))
201 			clk_prepare_enable(clk);
202 
203 		printk(KERN_INFO "link up\n");
204 
205 		pp->index = index;
206 		pp->root_bus_nr = -1;
207 		pp->base = base;
208 		spin_lock_init(&pp->conf_lock);
209 		memset(&pp->res, 0, sizeof(pp->res));
210 	} else {
211 		printk(KERN_INFO "link down, ignoring\n");
212 	}
213 }
214 
215 void __init dove_pcie_init(int init_port0, int init_port1)
216 {
217 	vga_base = DOVE_PCIE0_MEM_PHYS_BASE;
218 
219 	if (init_port0)
220 		add_pcie_port(0, DOVE_PCIE0_VIRT_BASE);
221 
222 	if (init_port1)
223 		add_pcie_port(1, DOVE_PCIE1_VIRT_BASE);
224 
225 	pci_common_init(&dove_pci);
226 }
227