blob: b4fa6413c4e52fbdf71c3ec62126577f1ff8f67a [file] [log] [blame]
Sergey Ryazanov3ed7a2a2014-10-29 03:18:47 +04001/*
2 * This program is free software; you can redistribute it and/or
3 * modify it under the terms of the GNU General Public License
4 * as published by the Free Software Foundation; either version 2
5 * of the License, or (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, see <http://www.gnu.org/licenses/>.
14 */
15
16/**
17 * Both AR2315 and AR2316 chips have PCI interface unit, which supports DMA
18 * and interrupt. PCI interface supports MMIO access method, but does not
19 * seem to support I/O ports.
20 *
21 * Read/write operation in the region 0x80000000-0xBFFFFFFF causes
22 * a memory read/write command on the PCI bus. 30 LSBs of address on
23 * the bus are taken from memory read/write request and 2 MSBs are
24 * determined by PCI unit configuration.
25 *
26 * To work with the configuration space instead of memory is necessary set
27 * the CFG_SEL bit in the PCI_MISC_CONFIG register.
28 *
29 * Devices on the bus can perform DMA requests via chip BAR1. PCI host
30 * controller BARs are programmend as if an external device is programmed.
31 * Which means that during configuration, IDSEL pin of the chip should be
32 * asserted.
33 *
34 * We know (and support) only one board that uses the PCI interface -
35 * Fonera 2.0g (FON2202). It has a USB EHCI controller connected to the
36 * AR2315 PCI bus. IDSEL pin of USB controller is connected to AD[13] line
37 * and IDSEL pin of AR2315 is connected to AD[16] line.
38 */
39
40#include <linux/types.h>
41#include <linux/pci.h>
42#include <linux/platform_device.h>
43#include <linux/kernel.h>
44#include <linux/init.h>
45#include <linux/mm.h>
46#include <linux/delay.h>
47#include <linux/bitops.h>
48#include <linux/irq.h>
49#include <linux/irqdomain.h>
50#include <linux/io.h>
51#include <asm/paccess.h>
52
53/*
54 * PCI Bus Interface Registers
55 */
56#define AR2315_PCI_1MS_REG 0x0008
57
58#define AR2315_PCI_1MS_MASK 0x3FFFF /* # of AHB clk cycles in 1ms */
59
60#define AR2315_PCI_MISC_CONFIG 0x000c
61
62#define AR2315_PCIMISC_TXD_EN 0x00000001 /* Enable TXD for fragments */
63#define AR2315_PCIMISC_CFG_SEL 0x00000002 /* Mem or Config cycles */
64#define AR2315_PCIMISC_GIG_MASK 0x0000000C /* bits 31-30 for pci req */
65#define AR2315_PCIMISC_RST_MODE 0x00000030
66#define AR2315_PCIRST_INPUT 0x00000000 /* 4:5=0 rst is input */
67#define AR2315_PCIRST_LOW 0x00000010 /* 4:5=1 rst to GND */
68#define AR2315_PCIRST_HIGH 0x00000020 /* 4:5=2 rst to VDD */
69#define AR2315_PCIGRANT_EN 0x00000000 /* 6:7=0 early grant en */
70#define AR2315_PCIGRANT_FRAME 0x00000040 /* 6:7=1 grant waits 4 frame */
71#define AR2315_PCIGRANT_IDLE 0x00000080 /* 6:7=2 grant waits 4 idle */
72#define AR2315_PCIGRANT_GAP 0x00000000 /* 6:7=2 grant waits 4 idle */
73#define AR2315_PCICACHE_DIS 0x00001000 /* PCI external access cache
74 * disable */
75
76#define AR2315_PCI_OUT_TSTAMP 0x0010
77
78#define AR2315_PCI_UNCACHE_CFG 0x0014
79
80#define AR2315_PCI_IN_EN 0x0100
81
82#define AR2315_PCI_IN_EN0 0x01 /* Enable chain 0 */
83#define AR2315_PCI_IN_EN1 0x02 /* Enable chain 1 */
84#define AR2315_PCI_IN_EN2 0x04 /* Enable chain 2 */
85#define AR2315_PCI_IN_EN3 0x08 /* Enable chain 3 */
86
87#define AR2315_PCI_IN_DIS 0x0104
88
89#define AR2315_PCI_IN_DIS0 0x01 /* Disable chain 0 */
90#define AR2315_PCI_IN_DIS1 0x02 /* Disable chain 1 */
91#define AR2315_PCI_IN_DIS2 0x04 /* Disable chain 2 */
92#define AR2315_PCI_IN_DIS3 0x08 /* Disable chain 3 */
93
94#define AR2315_PCI_IN_PTR 0x0200
95
96#define AR2315_PCI_OUT_EN 0x0400
97
98#define AR2315_PCI_OUT_EN0 0x01 /* Enable chain 0 */
99
100#define AR2315_PCI_OUT_DIS 0x0404
101
102#define AR2315_PCI_OUT_DIS0 0x01 /* Disable chain 0 */
103
104#define AR2315_PCI_OUT_PTR 0x0408
105
106/* PCI interrupt status (write one to clear) */
107#define AR2315_PCI_ISR 0x0500
108
109#define AR2315_PCI_INT_TX 0x00000001 /* Desc In Completed */
110#define AR2315_PCI_INT_TXOK 0x00000002 /* Desc In OK */
111#define AR2315_PCI_INT_TXERR 0x00000004 /* Desc In ERR */
112#define AR2315_PCI_INT_TXEOL 0x00000008 /* Desc In End-of-List */
113#define AR2315_PCI_INT_RX 0x00000010 /* Desc Out Completed */
114#define AR2315_PCI_INT_RXOK 0x00000020 /* Desc Out OK */
115#define AR2315_PCI_INT_RXERR 0x00000040 /* Desc Out ERR */
116#define AR2315_PCI_INT_RXEOL 0x00000080 /* Desc Out EOL */
117#define AR2315_PCI_INT_TXOOD 0x00000200 /* Desc In Out-of-Desc */
118#define AR2315_PCI_INT_DESCMASK 0x0000FFFF /* Desc Mask */
119#define AR2315_PCI_INT_EXT 0x02000000 /* Extern PCI INTA */
120#define AR2315_PCI_INT_ABORT 0x04000000 /* PCI bus abort event */
121
122/* PCI interrupt mask */
123#define AR2315_PCI_IMR 0x0504
124
125/* Global PCI interrupt enable */
126#define AR2315_PCI_IER 0x0508
127
128#define AR2315_PCI_IER_DISABLE 0x00 /* disable pci interrupts */
129#define AR2315_PCI_IER_ENABLE 0x01 /* enable pci interrupts */
130
131#define AR2315_PCI_HOST_IN_EN 0x0800
132#define AR2315_PCI_HOST_IN_DIS 0x0804
133#define AR2315_PCI_HOST_IN_PTR 0x0810
134#define AR2315_PCI_HOST_OUT_EN 0x0900
135#define AR2315_PCI_HOST_OUT_DIS 0x0904
136#define AR2315_PCI_HOST_OUT_PTR 0x0908
137
138/*
139 * PCI interrupts, which share IP5
140 * Keep ordered according to AR2315_PCI_INT_XXX bits
141 */
142#define AR2315_PCI_IRQ_EXT 25
143#define AR2315_PCI_IRQ_ABORT 26
144#define AR2315_PCI_IRQ_COUNT 27
145
146/* Arbitrary size of memory region to access the configuration space */
147#define AR2315_PCI_CFG_SIZE 0x00100000
148
149#define AR2315_PCI_HOST_SLOT 3
150#define AR2315_PCI_HOST_DEVID ((0xff18 << 16) | PCI_VENDOR_ID_ATHEROS)
151
152/* ??? access BAR */
153#define AR2315_PCI_HOST_MBAR0 0x10000000
154/* RAM access BAR */
155#define AR2315_PCI_HOST_MBAR1 AR2315_PCI_HOST_SDRAM_BASEADDR
156/* ??? access BAR */
157#define AR2315_PCI_HOST_MBAR2 0x30000000
158
159struct ar2315_pci_ctrl {
160 void __iomem *cfg_mem;
161 void __iomem *mmr_mem;
162 unsigned irq;
163 unsigned irq_ext;
164 struct irq_domain *domain;
165 struct pci_controller pci_ctrl;
166 struct resource mem_res;
167 struct resource io_res;
168};
169
170static inline struct ar2315_pci_ctrl *ar2315_pci_bus_to_apc(struct pci_bus *bus)
171{
172 struct pci_controller *hose = bus->sysdata;
173
174 return container_of(hose, struct ar2315_pci_ctrl, pci_ctrl);
175}
176
177static inline u32 ar2315_pci_reg_read(struct ar2315_pci_ctrl *apc, u32 reg)
178{
179 return __raw_readl(apc->mmr_mem + reg);
180}
181
182static inline void ar2315_pci_reg_write(struct ar2315_pci_ctrl *apc, u32 reg,
183 u32 val)
184{
185 __raw_writel(val, apc->mmr_mem + reg);
186}
187
188static inline void ar2315_pci_reg_mask(struct ar2315_pci_ctrl *apc, u32 reg,
189 u32 mask, u32 val)
190{
191 u32 ret = ar2315_pci_reg_read(apc, reg);
192
193 ret &= ~mask;
194 ret |= val;
195 ar2315_pci_reg_write(apc, reg, ret);
196}
197
198static int ar2315_pci_cfg_access(struct ar2315_pci_ctrl *apc, unsigned devfn,
199 int where, int size, u32 *ptr, bool write)
200{
201 int func = PCI_FUNC(devfn);
202 int dev = PCI_SLOT(devfn);
203 u32 addr = (1 << (13 + dev)) | (func << 8) | (where & ~3);
204 u32 mask = 0xffffffff >> 8 * (4 - size);
205 u32 sh = (where & 3) * 8;
206 u32 value, isr;
207
208 /* Prevent access past the remapped area */
209 if (addr >= AR2315_PCI_CFG_SIZE || dev > 18)
210 return PCIBIOS_DEVICE_NOT_FOUND;
211
212 /* Clear pending errors */
213 ar2315_pci_reg_write(apc, AR2315_PCI_ISR, AR2315_PCI_INT_ABORT);
214 /* Select Configuration access */
215 ar2315_pci_reg_mask(apc, AR2315_PCI_MISC_CONFIG, 0,
216 AR2315_PCIMISC_CFG_SEL);
217
218 mb(); /* PCI must see space change before we begin */
219
220 value = __raw_readl(apc->cfg_mem + addr);
221
222 isr = ar2315_pci_reg_read(apc, AR2315_PCI_ISR);
223
224 if (isr & AR2315_PCI_INT_ABORT)
225 goto exit_err;
226
227 if (write) {
228 value = (value & ~(mask << sh)) | *ptr << sh;
229 __raw_writel(value, apc->cfg_mem + addr);
230 isr = ar2315_pci_reg_read(apc, AR2315_PCI_ISR);
231 if (isr & AR2315_PCI_INT_ABORT)
232 goto exit_err;
233 } else {
234 *ptr = (value >> sh) & mask;
235 }
236
237 goto exit;
238
239exit_err:
240 ar2315_pci_reg_write(apc, AR2315_PCI_ISR, AR2315_PCI_INT_ABORT);
241 if (!write)
242 *ptr = 0xffffffff;
243
244exit:
245 /* Select Memory access */
246 ar2315_pci_reg_mask(apc, AR2315_PCI_MISC_CONFIG, AR2315_PCIMISC_CFG_SEL,
247 0);
248
249 return isr & AR2315_PCI_INT_ABORT ? PCIBIOS_DEVICE_NOT_FOUND :
250 PCIBIOS_SUCCESSFUL;
251}
252
253static inline int ar2315_pci_local_cfg_rd(struct ar2315_pci_ctrl *apc,
254 unsigned devfn, int where, u32 *val)
255{
256 return ar2315_pci_cfg_access(apc, devfn, where, sizeof(u32), val,
257 false);
258}
259
260static inline int ar2315_pci_local_cfg_wr(struct ar2315_pci_ctrl *apc,
261 unsigned devfn, int where, u32 val)
262{
263 return ar2315_pci_cfg_access(apc, devfn, where, sizeof(u32), &val,
264 true);
265}
266
267static int ar2315_pci_cfg_read(struct pci_bus *bus, unsigned devfn, int where,
268 int size, u32 *value)
269{
270 struct ar2315_pci_ctrl *apc = ar2315_pci_bus_to_apc(bus);
271
272 if (PCI_SLOT(devfn) == AR2315_PCI_HOST_SLOT)
273 return PCIBIOS_DEVICE_NOT_FOUND;
274
275 return ar2315_pci_cfg_access(apc, devfn, where, size, value, false);
276}
277
278static int ar2315_pci_cfg_write(struct pci_bus *bus, unsigned devfn, int where,
279 int size, u32 value)
280{
281 struct ar2315_pci_ctrl *apc = ar2315_pci_bus_to_apc(bus);
282
283 if (PCI_SLOT(devfn) == AR2315_PCI_HOST_SLOT)
284 return PCIBIOS_DEVICE_NOT_FOUND;
285
286 return ar2315_pci_cfg_access(apc, devfn, where, size, &value, true);
287}
288
289static struct pci_ops ar2315_pci_ops = {
290 .read = ar2315_pci_cfg_read,
291 .write = ar2315_pci_cfg_write,
292};
293
294static int ar2315_pci_host_setup(struct ar2315_pci_ctrl *apc)
295{
296 unsigned devfn = PCI_DEVFN(AR2315_PCI_HOST_SLOT, 0);
297 int res;
298 u32 id;
299
300 res = ar2315_pci_local_cfg_rd(apc, devfn, PCI_VENDOR_ID, &id);
301 if (res != PCIBIOS_SUCCESSFUL || id != AR2315_PCI_HOST_DEVID)
302 return -ENODEV;
303
304 /* Program MBARs */
305 ar2315_pci_local_cfg_wr(apc, devfn, PCI_BASE_ADDRESS_0,
306 AR2315_PCI_HOST_MBAR0);
307 ar2315_pci_local_cfg_wr(apc, devfn, PCI_BASE_ADDRESS_1,
308 AR2315_PCI_HOST_MBAR1);
309 ar2315_pci_local_cfg_wr(apc, devfn, PCI_BASE_ADDRESS_2,
310 AR2315_PCI_HOST_MBAR2);
311
312 /* Run */
313 ar2315_pci_local_cfg_wr(apc, devfn, PCI_COMMAND, PCI_COMMAND_MEMORY |
314 PCI_COMMAND_MASTER | PCI_COMMAND_SPECIAL |
315 PCI_COMMAND_INVALIDATE | PCI_COMMAND_PARITY |
316 PCI_COMMAND_SERR | PCI_COMMAND_FAST_BACK);
317
318 return 0;
319}
320
Thomas Gleixnerbd0b9ac2015-09-14 10:42:37 +0200321static void ar2315_pci_irq_handler(struct irq_desc *desc)
Sergey Ryazanov3ed7a2a2014-10-29 03:18:47 +0400322{
Jiang Liu25aae562015-05-20 17:59:51 +0800323 struct ar2315_pci_ctrl *apc = irq_desc_get_handler_data(desc);
Sergey Ryazanov3ed7a2a2014-10-29 03:18:47 +0400324 u32 pending = ar2315_pci_reg_read(apc, AR2315_PCI_ISR) &
325 ar2315_pci_reg_read(apc, AR2315_PCI_IMR);
326 unsigned pci_irq = 0;
327
328 if (pending)
329 pci_irq = irq_find_mapping(apc->domain, __ffs(pending));
330
331 if (pci_irq)
332 generic_handle_irq(pci_irq);
333 else
334 spurious_interrupt();
335}
336
337static void ar2315_pci_irq_mask(struct irq_data *d)
338{
339 struct ar2315_pci_ctrl *apc = irq_data_get_irq_chip_data(d);
340
341 ar2315_pci_reg_mask(apc, AR2315_PCI_IMR, BIT(d->hwirq), 0);
342}
343
344static void ar2315_pci_irq_mask_ack(struct irq_data *d)
345{
346 struct ar2315_pci_ctrl *apc = irq_data_get_irq_chip_data(d);
347 u32 m = BIT(d->hwirq);
348
349 ar2315_pci_reg_mask(apc, AR2315_PCI_IMR, m, 0);
350 ar2315_pci_reg_write(apc, AR2315_PCI_ISR, m);
351}
352
353static void ar2315_pci_irq_unmask(struct irq_data *d)
354{
355 struct ar2315_pci_ctrl *apc = irq_data_get_irq_chip_data(d);
356
357 ar2315_pci_reg_mask(apc, AR2315_PCI_IMR, 0, BIT(d->hwirq));
358}
359
360static struct irq_chip ar2315_pci_irq_chip = {
361 .name = "AR2315-PCI",
362 .irq_mask = ar2315_pci_irq_mask,
363 .irq_mask_ack = ar2315_pci_irq_mask_ack,
364 .irq_unmask = ar2315_pci_irq_unmask,
365};
366
367static int ar2315_pci_irq_map(struct irq_domain *d, unsigned irq,
368 irq_hw_number_t hw)
369{
370 irq_set_chip_and_handler(irq, &ar2315_pci_irq_chip, handle_level_irq);
371 irq_set_chip_data(irq, d->host_data);
372 return 0;
373}
374
375static struct irq_domain_ops ar2315_pci_irq_domain_ops = {
376 .map = ar2315_pci_irq_map,
377};
378
379static void ar2315_pci_irq_init(struct ar2315_pci_ctrl *apc)
380{
381 ar2315_pci_reg_mask(apc, AR2315_PCI_IER, AR2315_PCI_IER_ENABLE, 0);
382 ar2315_pci_reg_mask(apc, AR2315_PCI_IMR, (AR2315_PCI_INT_ABORT |
383 AR2315_PCI_INT_EXT), 0);
384
385 apc->irq_ext = irq_create_mapping(apc->domain, AR2315_PCI_IRQ_EXT);
386
Thomas Gleixner746ad9a2015-06-21 21:00:38 +0200387 irq_set_chained_handler_and_data(apc->irq, ar2315_pci_irq_handler,
388 apc);
Sergey Ryazanov3ed7a2a2014-10-29 03:18:47 +0400389
390 /* Clear any pending Abort or external Interrupts
391 * and enable interrupt processing */
392 ar2315_pci_reg_write(apc, AR2315_PCI_ISR, AR2315_PCI_INT_ABORT |
393 AR2315_PCI_INT_EXT);
394 ar2315_pci_reg_mask(apc, AR2315_PCI_IER, 0, AR2315_PCI_IER_ENABLE);
395}
396
397static int ar2315_pci_probe(struct platform_device *pdev)
398{
399 struct ar2315_pci_ctrl *apc;
400 struct device *dev = &pdev->dev;
401 struct resource *res;
402 int irq, err;
403
404 apc = devm_kzalloc(dev, sizeof(*apc), GFP_KERNEL);
405 if (!apc)
406 return -ENOMEM;
407
408 irq = platform_get_irq(pdev, 0);
409 if (irq < 0)
410 return -EINVAL;
411 apc->irq = irq;
412
413 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
414 "ar2315-pci-ctrl");
415 apc->mmr_mem = devm_ioremap_resource(dev, res);
416 if (IS_ERR(apc->mmr_mem))
417 return PTR_ERR(apc->mmr_mem);
418
419 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
420 "ar2315-pci-ext");
421 if (!res)
422 return -EINVAL;
423
424 apc->mem_res.name = "AR2315 PCI mem space";
425 apc->mem_res.parent = res;
426 apc->mem_res.start = res->start;
427 apc->mem_res.end = res->end;
428 apc->mem_res.flags = IORESOURCE_MEM;
429
430 /* Remap PCI config space */
431 apc->cfg_mem = devm_ioremap_nocache(dev, res->start,
432 AR2315_PCI_CFG_SIZE);
433 if (!apc->cfg_mem) {
434 dev_err(dev, "failed to remap PCI config space\n");
435 return -ENOMEM;
436 }
437
438 /* Reset the PCI bus by setting bits 5-4 in PCI_MCFG */
439 ar2315_pci_reg_mask(apc, AR2315_PCI_MISC_CONFIG,
440 AR2315_PCIMISC_RST_MODE,
441 AR2315_PCIRST_LOW);
442 msleep(100);
443
444 /* Bring the PCI out of reset */
445 ar2315_pci_reg_mask(apc, AR2315_PCI_MISC_CONFIG,
446 AR2315_PCIMISC_RST_MODE,
447 AR2315_PCIRST_HIGH | AR2315_PCICACHE_DIS | 0x8);
448
449 ar2315_pci_reg_write(apc, AR2315_PCI_UNCACHE_CFG,
450 0x1E | /* 1GB uncached */
451 (1 << 5) | /* Enable uncached */
452 (0x2 << 30) /* Base: 0x80000000 */);
453 ar2315_pci_reg_read(apc, AR2315_PCI_UNCACHE_CFG);
454
455 msleep(500);
456
457 err = ar2315_pci_host_setup(apc);
458 if (err)
459 return err;
460
461 apc->domain = irq_domain_add_linear(NULL, AR2315_PCI_IRQ_COUNT,
462 &ar2315_pci_irq_domain_ops, apc);
463 if (!apc->domain) {
464 dev_err(dev, "failed to add IRQ domain\n");
465 return -ENOMEM;
466 }
467
468 ar2315_pci_irq_init(apc);
469
470 /* PCI controller does not support I/O ports */
471 apc->io_res.name = "AR2315 IO space";
472 apc->io_res.start = 0;
473 apc->io_res.end = 0;
474 apc->io_res.flags = IORESOURCE_IO,
475
476 apc->pci_ctrl.pci_ops = &ar2315_pci_ops;
477 apc->pci_ctrl.mem_resource = &apc->mem_res,
478 apc->pci_ctrl.io_resource = &apc->io_res,
479
480 register_pci_controller(&apc->pci_ctrl);
481
482 dev_info(dev, "register PCI controller\n");
483
484 return 0;
485}
486
487static struct platform_driver ar2315_pci_driver = {
488 .probe = ar2315_pci_probe,
489 .driver = {
490 .name = "ar2315-pci",
Sergey Ryazanov3ed7a2a2014-10-29 03:18:47 +0400491 },
492};
493
494static int __init ar2315_pci_init(void)
495{
496 return platform_driver_register(&ar2315_pci_driver);
497}
498arch_initcall(ar2315_pci_init);
499
500int pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
501{
502 struct ar2315_pci_ctrl *apc = ar2315_pci_bus_to_apc(dev->bus);
503
504 return slot ? 0 : apc->irq_ext;
505}
506
507int pcibios_plat_dev_init(struct pci_dev *dev)
508{
509 return 0;
510}