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 unsigned busnr;
102 int irq;
103 unsigned long window_size;
104 unsigned long window_addr;
105 unsigned long window_pci;
106 };
107
108 /* PCI configuration space operations */
rcar_pci_cfg_base(struct pci_bus * bus,unsigned int devfn,int where)109 static void __iomem *rcar_pci_cfg_base(struct pci_bus *bus, unsigned int devfn,
110 int where)
111 {
112 struct pci_sys_data *sys = bus->sysdata;
113 struct rcar_pci_priv *priv = sys->private_data;
114 int slot, val;
115
116 if (sys->busnr != bus->number || PCI_FUNC(devfn))
117 return NULL;
118
119 /* Only one EHCI/OHCI device built-in */
120 slot = PCI_SLOT(devfn);
121 if (slot > 2)
122 return NULL;
123
124 /* bridge logic only has registers to 0x40 */
125 if (slot == 0x0 && where >= 0x40)
126 return NULL;
127
128 val = slot ? RCAR_AHBPCI_WIN1_DEVICE | RCAR_AHBPCI_WIN_CTR_CFG :
129 RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG;
130
131 iowrite32(val, priv->reg + RCAR_AHBPCI_WIN1_CTR_REG);
132 return priv->reg + (slot >> 1) * 0x100 + where;
133 }
134
135 /* PCI interrupt mapping */
rcar_pci_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)136 static int rcar_pci_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
137 {
138 struct pci_sys_data *sys = dev->bus->sysdata;
139 struct rcar_pci_priv *priv = sys->private_data;
140 int irq;
141
142 irq = of_irq_parse_and_map_pci(dev, slot, pin);
143 if (!irq)
144 irq = priv->irq;
145
146 return irq;
147 }
148
149 #ifdef CONFIG_PCI_DEBUG
150 /* if debug enabled, then attach an error handler irq to the bridge */
151
rcar_pci_err_irq(int irq,void * pw)152 static irqreturn_t rcar_pci_err_irq(int irq, void *pw)
153 {
154 struct rcar_pci_priv *priv = pw;
155 struct device *dev = priv->dev;
156 u32 status = ioread32(priv->reg + RCAR_PCI_INT_STATUS_REG);
157
158 if (status & RCAR_PCI_INT_ALLERRORS) {
159 dev_err(dev, "error irq: status %08x\n", status);
160
161 /* clear the error(s) */
162 iowrite32(status & RCAR_PCI_INT_ALLERRORS,
163 priv->reg + RCAR_PCI_INT_STATUS_REG);
164 return IRQ_HANDLED;
165 }
166
167 return IRQ_NONE;
168 }
169
rcar_pci_setup_errirq(struct rcar_pci_priv * priv)170 static void rcar_pci_setup_errirq(struct rcar_pci_priv *priv)
171 {
172 struct device *dev = priv->dev;
173 int ret;
174 u32 val;
175
176 ret = devm_request_irq(dev, priv->irq, rcar_pci_err_irq,
177 IRQF_SHARED, "error irq", priv);
178 if (ret) {
179 dev_err(dev, "cannot claim IRQ for error handling\n");
180 return;
181 }
182
183 val = ioread32(priv->reg + RCAR_PCI_INT_ENABLE_REG);
184 val |= RCAR_PCI_INT_ALLERRORS;
185 iowrite32(val, priv->reg + RCAR_PCI_INT_ENABLE_REG);
186 }
187 #else
rcar_pci_setup_errirq(struct rcar_pci_priv * priv)188 static inline void rcar_pci_setup_errirq(struct rcar_pci_priv *priv) { }
189 #endif
190
191 /* PCI host controller setup */
rcar_pci_setup(int nr,struct pci_sys_data * sys)192 static int rcar_pci_setup(int nr, struct pci_sys_data *sys)
193 {
194 struct rcar_pci_priv *priv = sys->private_data;
195 struct device *dev = priv->dev;
196 void __iomem *reg = priv->reg;
197 u32 val;
198 int ret;
199
200 pm_runtime_enable(dev);
201 pm_runtime_get_sync(dev);
202
203 val = ioread32(reg + RCAR_PCI_UNIT_REV_REG);
204 dev_info(dev, "PCI: bus%u revision %x\n", sys->busnr, val);
205
206 /* Disable Direct Power Down State and assert reset */
207 val = ioread32(reg + RCAR_USBCTR_REG) & ~RCAR_USBCTR_DIRPD;
208 val |= RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST;
209 iowrite32(val, reg + RCAR_USBCTR_REG);
210 udelay(4);
211
212 /* De-assert reset and reset PCIAHB window1 size */
213 val &= ~(RCAR_USBCTR_PCIAHB_WIN1_MASK | RCAR_USBCTR_PCICLK_MASK |
214 RCAR_USBCTR_USBH_RST | RCAR_USBCTR_PLL_RST);
215
216 /* Setup PCIAHB window1 size */
217 switch (priv->window_size) {
218 case SZ_2G:
219 val |= RCAR_USBCTR_PCIAHB_WIN1_2G;
220 break;
221 case SZ_1G:
222 val |= RCAR_USBCTR_PCIAHB_WIN1_1G;
223 break;
224 case SZ_512M:
225 val |= RCAR_USBCTR_PCIAHB_WIN1_512M;
226 break;
227 default:
228 pr_warn("unknown window size %ld - defaulting to 256M\n",
229 priv->window_size);
230 priv->window_size = SZ_256M;
231 /* fall-through */
232 case SZ_256M:
233 val |= RCAR_USBCTR_PCIAHB_WIN1_256M;
234 break;
235 }
236 iowrite32(val, reg + RCAR_USBCTR_REG);
237
238 /* Configure AHB master and slave modes */
239 iowrite32(RCAR_AHB_BUS_MODE, reg + RCAR_AHB_BUS_CTR_REG);
240
241 /* Configure PCI arbiter */
242 val = ioread32(reg + RCAR_PCI_ARBITER_CTR_REG);
243 val |= RCAR_PCI_ARBITER_PCIREQ0 | RCAR_PCI_ARBITER_PCIREQ1 |
244 RCAR_PCI_ARBITER_PCIBP_MODE;
245 iowrite32(val, reg + RCAR_PCI_ARBITER_CTR_REG);
246
247 /* PCI-AHB mapping */
248 iowrite32(priv->window_addr | RCAR_PCIAHB_PREFETCH16,
249 reg + RCAR_PCIAHB_WIN1_CTR_REG);
250
251 /* AHB-PCI mapping: OHCI/EHCI registers */
252 val = priv->mem_res.start | RCAR_AHBPCI_WIN_CTR_MEM;
253 iowrite32(val, reg + RCAR_AHBPCI_WIN2_CTR_REG);
254
255 /* Enable AHB-PCI bridge PCI configuration access */
256 iowrite32(RCAR_AHBPCI_WIN1_HOST | RCAR_AHBPCI_WIN_CTR_CFG,
257 reg + RCAR_AHBPCI_WIN1_CTR_REG);
258 /* Set PCI-AHB Window1 address */
259 iowrite32(priv->window_pci | PCI_BASE_ADDRESS_MEM_PREFETCH,
260 reg + PCI_BASE_ADDRESS_1);
261 /* Set AHB-PCI bridge PCI communication area address */
262 val = priv->cfg_res->start + RCAR_AHBPCI_PCICOM_OFFSET;
263 iowrite32(val, reg + PCI_BASE_ADDRESS_0);
264
265 val = ioread32(reg + PCI_COMMAND);
266 val |= PCI_COMMAND_SERR | PCI_COMMAND_PARITY |
267 PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
268 iowrite32(val, reg + PCI_COMMAND);
269
270 /* Enable PCI interrupts */
271 iowrite32(RCAR_PCI_INT_A | RCAR_PCI_INT_B | RCAR_PCI_INT_PME,
272 reg + RCAR_PCI_INT_ENABLE_REG);
273
274 if (priv->irq > 0)
275 rcar_pci_setup_errirq(priv);
276
277 /* Add PCI resources */
278 pci_add_resource(&sys->resources, &priv->mem_res);
279 ret = devm_request_pci_bus_resources(dev, &sys->resources);
280 if (ret < 0)
281 return ret;
282
283 /* Setup bus number based on platform device id / of bus-range */
284 sys->busnr = priv->busnr;
285 return 1;
286 }
287
288 static struct pci_ops rcar_pci_ops = {
289 .map_bus = rcar_pci_cfg_base,
290 .read = pci_generic_config_read,
291 .write = pci_generic_config_write,
292 };
293
rcar_pci_parse_map_dma_ranges(struct rcar_pci_priv * pci,struct device_node * np)294 static int rcar_pci_parse_map_dma_ranges(struct rcar_pci_priv *pci,
295 struct device_node *np)
296 {
297 struct device *dev = pci->dev;
298 struct of_pci_range range;
299 struct of_pci_range_parser parser;
300 int index = 0;
301
302 /* Failure to parse is ok as we fall back to defaults */
303 if (of_pci_dma_range_parser_init(&parser, np))
304 return 0;
305
306 /* Get the dma-ranges from DT */
307 for_each_of_pci_range(&parser, &range) {
308 /* Hardware only allows one inbound 32-bit range */
309 if (index)
310 return -EINVAL;
311
312 pci->window_addr = (unsigned long)range.cpu_addr;
313 pci->window_pci = (unsigned long)range.pci_addr;
314 pci->window_size = (unsigned long)range.size;
315
316 /* Catch HW limitations */
317 if (!(range.flags & IORESOURCE_PREFETCH)) {
318 dev_err(dev, "window must be prefetchable\n");
319 return -EINVAL;
320 }
321 if (pci->window_addr) {
322 u32 lowaddr = 1 << (ffs(pci->window_addr) - 1);
323
324 if (lowaddr < pci->window_size) {
325 dev_err(dev, "invalid window size/addr\n");
326 return -EINVAL;
327 }
328 }
329 index++;
330 }
331
332 return 0;
333 }
334
rcar_pci_probe(struct platform_device * pdev)335 static int rcar_pci_probe(struct platform_device *pdev)
336 {
337 struct device *dev = &pdev->dev;
338 struct resource *cfg_res, *mem_res;
339 struct rcar_pci_priv *priv;
340 void __iomem *reg;
341 struct hw_pci hw;
342 void *hw_private[1];
343
344 cfg_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
345 reg = devm_ioremap_resource(dev, cfg_res);
346 if (IS_ERR(reg))
347 return PTR_ERR(reg);
348
349 mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
350 if (!mem_res || !mem_res->start)
351 return -ENODEV;
352
353 if (mem_res->start & 0xFFFF)
354 return -EINVAL;
355
356 priv = devm_kzalloc(dev, sizeof(struct rcar_pci_priv), GFP_KERNEL);
357 if (!priv)
358 return -ENOMEM;
359
360 priv->mem_res = *mem_res;
361 priv->cfg_res = cfg_res;
362
363 priv->irq = platform_get_irq(pdev, 0);
364 priv->reg = reg;
365 priv->dev = dev;
366
367 if (priv->irq < 0) {
368 dev_err(dev, "no valid irq found\n");
369 return priv->irq;
370 }
371
372 /* default window addr and size if not specified in DT */
373 priv->window_addr = 0x40000000;
374 priv->window_pci = 0x40000000;
375 priv->window_size = SZ_1G;
376
377 if (dev->of_node) {
378 struct resource busnr;
379 int ret;
380
381 ret = of_pci_parse_bus_range(dev->of_node, &busnr);
382 if (ret < 0) {
383 dev_err(dev, "failed to parse bus-range\n");
384 return ret;
385 }
386
387 priv->busnr = busnr.start;
388 if (busnr.end != busnr.start)
389 dev_warn(dev, "only one bus number supported\n");
390
391 ret = rcar_pci_parse_map_dma_ranges(priv, dev->of_node);
392 if (ret < 0) {
393 dev_err(dev, "failed to parse dma-range\n");
394 return ret;
395 }
396 } else {
397 priv->busnr = pdev->id;
398 }
399
400 hw_private[0] = priv;
401 memset(&hw, 0, sizeof(hw));
402 hw.nr_controllers = ARRAY_SIZE(hw_private);
403 hw.io_optional = 1;
404 hw.private_data = hw_private;
405 hw.map_irq = rcar_pci_map_irq;
406 hw.ops = &rcar_pci_ops;
407 hw.setup = rcar_pci_setup;
408 pci_common_init_dev(dev, &hw);
409 return 0;
410 }
411
412 static const struct of_device_id rcar_pci_of_match[] = {
413 { .compatible = "renesas,pci-r8a7790", },
414 { .compatible = "renesas,pci-r8a7791", },
415 { .compatible = "renesas,pci-r8a7794", },
416 { .compatible = "renesas,pci-rcar-gen2", },
417 { },
418 };
419
420 static struct platform_driver rcar_pci_driver = {
421 .driver = {
422 .name = "pci-rcar-gen2",
423 .suppress_bind_attrs = true,
424 .of_match_table = rcar_pci_of_match,
425 },
426 .probe = rcar_pci_probe,
427 };
428 builtin_platform_driver(rcar_pci_driver);
429