1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * pci-rcar-gen2: internal PCI bus support
4 *
5 * Copyright (C) 2013 Renesas Solutions Corp.
6 * Copyright (C) 2013 Cogent Embedded, Inc.
7 *
8 * Author: Valentine Barshak <valentine.barshak@cogentembedded.com>
9 */
10
11 #include <linux/delay.h>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/kernel.h>
16 #include <linux/of_address.h>
17 #include <linux/of_pci.h>
18 #include <linux/pci.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/sizes.h>
22 #include <linux/slab.h>
23
24 #include "../pci.h"
25
26 /* AHB-PCI Bridge PCI communication registers */
27 #define RCAR_AHBPCI_PCICOM_OFFSET 0x800
28
29 #define RCAR_PCIAHB_WIN1_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x00)
30 #define RCAR_PCIAHB_WIN2_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x04)
31 #define RCAR_PCIAHB_PREFETCH0 0x0
32 #define RCAR_PCIAHB_PREFETCH4 0x1
33 #define RCAR_PCIAHB_PREFETCH8 0x2
34 #define RCAR_PCIAHB_PREFETCH16 0x3
35
36 #define RCAR_AHBPCI_WIN1_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x10)
37 #define RCAR_AHBPCI_WIN2_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x14)
38 #define RCAR_AHBPCI_WIN_CTR_MEM (3 << 1)
39 #define RCAR_AHBPCI_WIN_CTR_CFG (5 << 1)
40 #define RCAR_AHBPCI_WIN1_HOST (1 << 30)
41 #define RCAR_AHBPCI_WIN1_DEVICE (1 << 31)
42
43 #define RCAR_PCI_INT_ENABLE_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x20)
44 #define RCAR_PCI_INT_STATUS_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x24)
45 #define RCAR_PCI_INT_SIGTABORT (1 << 0)
46 #define RCAR_PCI_INT_SIGRETABORT (1 << 1)
47 #define RCAR_PCI_INT_REMABORT (1 << 2)
48 #define RCAR_PCI_INT_PERR (1 << 3)
49 #define RCAR_PCI_INT_SIGSERR (1 << 4)
50 #define RCAR_PCI_INT_RESERR (1 << 5)
51 #define RCAR_PCI_INT_WIN1ERR (1 << 12)
52 #define RCAR_PCI_INT_WIN2ERR (1 << 13)
53 #define RCAR_PCI_INT_A (1 << 16)
54 #define RCAR_PCI_INT_B (1 << 17)
55 #define RCAR_PCI_INT_PME (1 << 19)
56 #define RCAR_PCI_INT_ALLERRORS (RCAR_PCI_INT_SIGTABORT | \
57 RCAR_PCI_INT_SIGRETABORT | \
58 RCAR_PCI_INT_REMABORT | \
59 RCAR_PCI_INT_PERR | \
60 RCAR_PCI_INT_SIGSERR | \
61 RCAR_PCI_INT_RESERR | \
62 RCAR_PCI_INT_WIN1ERR | \
63 RCAR_PCI_INT_WIN2ERR)
64
65 #define RCAR_AHB_BUS_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x30)
66 #define RCAR_AHB_BUS_MMODE_HTRANS (1 << 0)
67 #define RCAR_AHB_BUS_MMODE_BYTE_BURST (1 << 1)
68 #define RCAR_AHB_BUS_MMODE_WR_INCR (1 << 2)
69 #define RCAR_AHB_BUS_MMODE_HBUS_REQ (1 << 7)
70 #define RCAR_AHB_BUS_SMODE_READYCTR (1 << 17)
71 #define RCAR_AHB_BUS_MODE (RCAR_AHB_BUS_MMODE_HTRANS | \
72 RCAR_AHB_BUS_MMODE_BYTE_BURST | \
73 RCAR_AHB_BUS_MMODE_WR_INCR | \
74 RCAR_AHB_BUS_MMODE_HBUS_REQ | \
75 RCAR_AHB_BUS_SMODE_READYCTR)
76
77 #define RCAR_USBCTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x34)
78 #define RCAR_USBCTR_USBH_RST (1 << 0)
79 #define RCAR_USBCTR_PCICLK_MASK (1 << 1)
80 #define RCAR_USBCTR_PLL_RST (1 << 2)
81 #define RCAR_USBCTR_DIRPD (1 << 8)
82 #define RCAR_USBCTR_PCIAHB_WIN2_EN (1 << 9)
83 #define RCAR_USBCTR_PCIAHB_WIN1_256M (0 << 10)
84 #define RCAR_USBCTR_PCIAHB_WIN1_512M (1 << 10)
85 #define RCAR_USBCTR_PCIAHB_WIN1_1G (2 << 10)
86 #define RCAR_USBCTR_PCIAHB_WIN1_2G (3 << 10)
87 #define RCAR_USBCTR_PCIAHB_WIN1_MASK (3 << 10)
88
89 #define RCAR_PCI_ARBITER_CTR_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x40)
90 #define RCAR_PCI_ARBITER_PCIREQ0 (1 << 0)
91 #define RCAR_PCI_ARBITER_PCIREQ1 (1 << 1)
92 #define RCAR_PCI_ARBITER_PCIBP_MODE (1 << 12)
93
94 #define RCAR_PCI_UNIT_REV_REG (RCAR_AHBPCI_PCICOM_OFFSET + 0x48)
95
96 struct rcar_pci_priv {
97 struct device *dev;
98 void __iomem *reg;
99 struct resource mem_res;
100 struct resource *cfg_res;
101 int irq;
102 };
103
104 /* PCI configuration space operations */
rcar_pci_cfg_base(struct pci_bus * bus,unsigned int devfn,int where)105 static void __iomem *rcar_pci_cfg_base(struct pci_bus *bus, unsigned int devfn,
106 int where)
107 {
108 struct rcar_pci_priv *priv = bus->sysdata;
109 int slot, val;
110
111 if (!pci_is_root_bus(bus) || PCI_FUNC(devfn))
112 return NULL;
113
114 /* Only one EHCI/OHCI device built-in */
115 slot = PCI_SLOT(devfn);
116 if (slot > 2)
117 return NULL;
118
119 /* bridge logic only has registers to 0x40 */
120 if (slot == 0x0 && where >= 0x40)
121 return NULL;
122
123 val = slot ? RCAR_AHBPCI_WIN1_DEVICE | RCAR_AHBPCI_WIN_CTR_CFG :
124 RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG;
125
126 iowrite32(val, priv->reg + RCAR_AHBPCI_WIN1_CTR_REG);
127 return priv->reg + (slot >> 1) * 0x100 + where;
128 }
129
130 #ifdef CONFIG_PCI_DEBUG
131 /* if debug enabled, then attach an error handler irq to the bridge */
132
rcar_pci_err_irq(int irq,void * pw)133 static irqreturn_t rcar_pci_err_irq(int irq, void *pw)
134 {
135 struct rcar_pci_priv *priv = pw;
136 struct device *dev = priv->dev;
137 u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
138
139 if (status & RCAR_PCI_INT_ALLERRORS) {
140 dev_err(dev, "error irq: status %08x\n", status);
141
142 /* clear the error(s) */
143 iowrite32(status & RCAR_PCI_INT_ALLERRORS,
144 priv->reg + RCAR_PCI_INT_STATUS_REG);
145 return IRQ_HANDLED;
146 }
147
148 return IRQ_NONE;
149 }
150
rcar_pci_setup_errirq(struct rcar_pci_priv * priv)151 static void rcar_pci_setup_errirq(struct rcar_pci_priv *priv)
152 {
153 struct device *dev = priv->dev;
154 int ret;
155 u32 val;
156
157 ret = devm_request_irq(dev, priv->irq, rcar_pci_err_irq,
158 IRQF_SHARED, "error irq", priv);
159 if (ret) {
160 dev_err(dev, "cannot claim IRQ for error handling\n");
161 return;
162 }
163
164 val = ioread32(priv->reg + RCAR_PCI_INT_ENABLE_REG);
165 val |= RCAR_PCI_INT_ALLERRORS;
166 iowrite32(val, priv->reg + RCAR_PCI_INT_ENABLE_REG);
167 }
168 #else
rcar_pci_setup_errirq(struct rcar_pci_priv * priv)169 static inline void rcar_pci_setup_errirq(struct rcar_pci_priv *priv) { }
170 #endif
171
172 /* PCI host controller setup */
rcar_pci_setup(struct rcar_pci_priv * priv)173 static void rcar_pci_setup(struct rcar_pci_priv *priv)
174 {
175 struct pci_host_bridge *bridge = pci_host_bridge_from_priv(priv);
176 struct device *dev = priv->dev;
177 void __iomem *reg = priv->reg;
178 struct resource_entry *entry;
179 unsigned long window_size;
180 unsigned long window_addr;
181 unsigned long window_pci;
182 u32 val;
183
184 entry = resource_list_first_type(&bridge->dma_ranges, IORESOURCE_MEM);
185 if (!entry) {
186 window_addr = 0x40000000;
187 window_pci = 0x40000000;
188 window_size = SZ_1G;
189 } else {
190 window_addr = entry->res->start;
191 window_pci = entry->res->start - entry->offset;
192 window_size = resource_size(entry->res);
193 }
194
195 pm_runtime_enable(dev);
196 pm_runtime_get_sync(dev);
197
198 val = ioread32(reg + RCAR_PCI_UNIT_REV_REG);
199 dev_info(dev, "PCI: revision %x\n", val);
200
201 /* Disable Direct Power Down State and assert reset */
202 val = ioread32(reg + RCAR_USBCTR_REG) & ~RCAR_USBCTR_DIRPD;
203 val |= RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST;
204 iowrite32(val, reg + RCAR_USBCTR_REG);
205 udelay(4);
206
207 /* De-assert reset and reset PCIAHB window1 size */
208 val &= ~(RCAR_USBCTR_PCIAHB_WIN1_MASK | RCAR_USBCTR_PCICLK_MASK |
209 RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST);
210
211 /* Setup PCIAHB window1 size */
212 switch (window_size) {
213 case SZ_2G:
214 val |= RCAR_USBCTR_PCIAHB_WIN1_2G;
215 break;
216 case SZ_1G:
217 val |= RCAR_USBCTR_PCIAHB_WIN1_1G;
218 break;
219 case SZ_512M:
220 val |= RCAR_USBCTR_PCIAHB_WIN1_512M;
221 break;
222 default:
223 pr_warn("unknown window size %ld - defaulting to 256M\n",
224 window_size);
225 window_size = SZ_256M;
226 fallthrough;
227 case SZ_256M:
228 val |= RCAR_USBCTR_PCIAHB_WIN1_256M;
229 break;
230 }
231 iowrite32(val, reg + RCAR_USBCTR_REG);
232
233 /* Configure AHB master and slave modes */
234 iowrite32(RCAR_AHB_BUS_MODE, reg + RCAR_AHB_BUS_CTR_REG);
235
236 /* Configure PCI arbiter */
237 val = ioread32(reg + RCAR_PCI_ARBITER_CTR_REG);
238 val |= RCAR_PCI_ARBITER_PCIREQ0 | RCAR_PCI_ARBITER_PCIREQ1 |
239 RCAR_PCI_ARBITER_PCIBP_MODE;
240 iowrite32(val, reg + RCAR_PCI_ARBITER_CTR_REG);
241
242 /* PCI-AHB mapping */
243 iowrite32(window_addr | RCAR_PCIAHB_PREFETCH16,
244 reg + RCAR_PCIAHB_WIN1_CTR_REG);
245
246 /* AHB-PCI mapping: OHCI/EHCI registers */
247 val = priv->mem_res.start | RCAR_AHBPCI_WIN_CTR_MEM;
248 iowrite32(val, reg + RCAR_AHBPCI_WIN2_CTR_REG);
249
250 /* Enable AHB-PCI bridge PCI configuration access */
251 iowrite32(RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG,
252 reg + RCAR_AHBPCI_WIN1_CTR_REG);
253 /* Set PCI-AHB Window1 address */
254 iowrite32(window_pci | PCI_BASE_ADDRESS_MEM_PREFETCH,
255 reg + PCI_BASE_ADDRESS_1);
256 /* Set AHB-PCI bridge PCI communication area address */
257 val = priv->cfg_res->start + RCAR_AHBPCI_PCICOM_OFFSET;
258 iowrite32(val, reg + PCI_BASE_ADDRESS_0);
259
260 val = ioread32(reg + PCI_COMMAND);
261 val |= PCI_COMMAND_SERR | PCI_COMMAND_PARITY |
262 PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
263 iowrite32(val, reg + PCI_COMMAND);
264
265 /* Enable PCI interrupts */
266 iowrite32(RCAR_PCI_INT_A | RCAR_PCI_INT_B | RCAR_PCI_INT_PME,
267 reg + RCAR_PCI_INT_ENABLE_REG);
268
269 rcar_pci_setup_errirq(priv);
270 }
271
272 static struct pci_ops rcar_pci_ops = {
273 .map_bus = rcar_pci_cfg_base,
274 .read = pci_generic_config_read,
275 .write = pci_generic_config_write,
276 };
277
rcar_pci_probe(struct platform_device * pdev)278 static int rcar_pci_probe(struct platform_device *pdev)
279 {
280 struct device *dev = &pdev->dev;
281 struct resource *cfg_res, *mem_res;
282 struct rcar_pci_priv *priv;
283 struct pci_host_bridge *bridge;
284 void __iomem *reg;
285
286 bridge = devm_pci_alloc_host_bridge(dev, sizeof(*priv));
287 if (!bridge)
288 return -ENOMEM;
289
290 priv = pci_host_bridge_priv(bridge);
291 bridge->sysdata = priv;
292
293 cfg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
294 reg = devm_ioremap_resource(dev, cfg_res);
295 if (IS_ERR(reg))
296 return PTR_ERR(reg);
297
298 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
299 if (!mem_res || !mem_res->start)
300 return -ENODEV;
301
302 if (mem_res->start & 0xFFFF)
303 return -EINVAL;
304
305 priv->mem_res = *mem_res;
306 priv->cfg_res = cfg_res;
307
308 priv->irq = platform_get_irq(pdev, 0);
309 priv->reg = reg;
310 priv->dev = dev;
311
312 if (priv->irq < 0) {
313 dev_err(dev, "no valid irq found\n");
314 return priv->irq;
315 }
316
317 bridge->ops = &rcar_pci_ops;
318
319 pci_add_flags(PCI_REASSIGN_ALL_BUS);
320
321 rcar_pci_setup(priv);
322
323 return pci_host_probe(bridge);
324 }
325
326 static const struct of_device_id rcar_pci_of_match[] = {
327 { .compatible = "renesas,pci-r8a7790", },
328 { .compatible = "renesas,pci-r8a7791", },
329 { .compatible = "renesas,pci-r8a7794", },
330 { .compatible = "renesas,pci-rcar-gen2", },
331 { },
332 };
333
334 static struct platform_driver rcar_pci_driver = {
335 .driver = {
336 .name = "pci-rcar-gen2",
337 .suppress_bind_attrs = true,
338 .of_match_table = rcar_pci_of_match,
339 },
340 .probe = rcar_pci_probe,
341 };
342 builtin_platform_driver(rcar_pci_driver);
343
