1 // SPDX-License-Identifier: GPL-2.0
3 * Support for Faraday Technology FTPC100 PCI Controller
5 * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
7 * Based on the out-of-tree OpenWRT patch for Cortina Gemini:
8 * Copyright (C) 2009 Janos Laube <janos.dev@gmail.com>
9 * Copyright (C) 2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
10 * Based on SL2312 PCI controller code
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
17 #include <linux/kernel.h>
18 #include <linux/of_address.h>
19 #include <linux/of_device.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_pci.h>
22 #include <linux/pci.h>
23 #include <linux/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/irqdomain.h>
26 #include <linux/irqchip/chained_irq.h>
27 #include <linux/bitops.h>
28 #include <linux/irq.h>
29 #include <linux/clk.h>
34 * Special configuration registers directly in the first few words
37 #define PCI_IOSIZE 0x00
38 #define PCI_PROT 0x04 /* AHB protection */
39 #define PCI_CTRL 0x08 /* PCI control signal */
40 #define PCI_SOFTRST 0x10 /* Soft reset counter and response error enable */
41 #define PCI_CONFIG 0x28 /* PCI configuration command register */
44 #define FARADAY_PCI_STATUS_CMD 0x04 /* Status and command */
45 #define FARADAY_PCI_PMC 0x40 /* Power management control */
46 #define FARADAY_PCI_PMCSR 0x44 /* Power management status */
47 #define FARADAY_PCI_CTRL1 0x48 /* Control register 1 */
48 #define FARADAY_PCI_CTRL2 0x4C /* Control register 2 */
49 #define FARADAY_PCI_MEM1_BASE_SIZE 0x50 /* Memory base and size #1 */
50 #define FARADAY_PCI_MEM2_BASE_SIZE 0x54 /* Memory base and size #2 */
51 #define FARADAY_PCI_MEM3_BASE_SIZE 0x58 /* Memory base and size #3 */
53 #define PCI_STATUS_66MHZ_CAPABLE BIT(21)
55 /* Bits 31..28 gives INTD..INTA status */
56 #define PCI_CTRL2_INTSTS_SHIFT 28
57 #define PCI_CTRL2_INTMASK_CMDERR BIT(27)
58 #define PCI_CTRL2_INTMASK_PARERR BIT(26)
59 /* Bits 25..22 masks INTD..INTA */
60 #define PCI_CTRL2_INTMASK_SHIFT 22
61 #define PCI_CTRL2_INTMASK_MABRT_RX BIT(21)
62 #define PCI_CTRL2_INTMASK_TABRT_RX BIT(20)
63 #define PCI_CTRL2_INTMASK_TABRT_TX BIT(19)
64 #define PCI_CTRL2_INTMASK_RETRY4 BIT(18)
65 #define PCI_CTRL2_INTMASK_SERR_RX BIT(17)
66 #define PCI_CTRL2_INTMASK_PERR_RX BIT(16)
68 #define PCI_CTRL2_MSTPRI_REQ6 BIT(14)
69 #define PCI_CTRL2_MSTPRI_REQ5 BIT(13)
70 #define PCI_CTRL2_MSTPRI_REQ4 BIT(12)
71 #define PCI_CTRL2_MSTPRI_REQ3 BIT(11)
72 #define PCI_CTRL2_MSTPRI_REQ2 BIT(10)
73 #define PCI_CTRL2_MSTPRI_REQ1 BIT(9)
74 #define PCI_CTRL2_MSTPRI_REQ0 BIT(8)
75 /* Bits 7..4 reserved */
80 * Bit 31..20 defines the PCI side memory base
81 * Bit 19..16 (4 bits) defines the size per below
83 #define FARADAY_PCI_MEMBASE_MASK 0xfff00000
84 #define FARADAY_PCI_MEMSIZE_1MB 0x0
85 #define FARADAY_PCI_MEMSIZE_2MB 0x1
86 #define FARADAY_PCI_MEMSIZE_4MB 0x2
87 #define FARADAY_PCI_MEMSIZE_8MB 0x3
88 #define FARADAY_PCI_MEMSIZE_16MB 0x4
89 #define FARADAY_PCI_MEMSIZE_32MB 0x5
90 #define FARADAY_PCI_MEMSIZE_64MB 0x6
91 #define FARADAY_PCI_MEMSIZE_128MB 0x7
92 #define FARADAY_PCI_MEMSIZE_256MB 0x8
93 #define FARADAY_PCI_MEMSIZE_512MB 0x9
94 #define FARADAY_PCI_MEMSIZE_1GB 0xa
95 #define FARADAY_PCI_MEMSIZE_2GB 0xb
96 #define FARADAY_PCI_MEMSIZE_SHIFT 16
99 * The DMA base is set to 0x0 for all memory segments, it reflects the
100 * fact that the memory of the host system starts at 0x0.
102 #define FARADAY_PCI_DMA_MEM1_BASE 0x00000000
103 #define FARADAY_PCI_DMA_MEM2_BASE 0x00000000
104 #define FARADAY_PCI_DMA_MEM3_BASE 0x00000000
106 /* Defines for PCI configuration command register */
107 #define PCI_CONF_ENABLE BIT(31)
108 #define PCI_CONF_WHERE(r) ((r) & 0xFC)
109 #define PCI_CONF_BUS(b) (((b) & 0xFF) << 16)
110 #define PCI_CONF_DEVICE(d) (((d) & 0x1F) << 11)
111 #define PCI_CONF_FUNCTION(f) (((f) & 0x07) << 8)
114 * struct faraday_pci_variant - encodes IP block differences
115 * @cascaded_irq: this host has cascaded IRQs from an interrupt controller
116 * embedded in the host bridge.
118 struct faraday_pci_variant
{
125 struct irq_domain
*irqdomain
;
130 static int faraday_res_to_memcfg(resource_size_t mem_base
,
131 resource_size_t mem_size
, u32
*val
)
137 outval
= FARADAY_PCI_MEMSIZE_1MB
;
140 outval
= FARADAY_PCI_MEMSIZE_2MB
;
143 outval
= FARADAY_PCI_MEMSIZE_4MB
;
146 outval
= FARADAY_PCI_MEMSIZE_8MB
;
149 outval
= FARADAY_PCI_MEMSIZE_16MB
;
152 outval
= FARADAY_PCI_MEMSIZE_32MB
;
155 outval
= FARADAY_PCI_MEMSIZE_64MB
;
158 outval
= FARADAY_PCI_MEMSIZE_128MB
;
161 outval
= FARADAY_PCI_MEMSIZE_256MB
;
164 outval
= FARADAY_PCI_MEMSIZE_512MB
;
167 outval
= FARADAY_PCI_MEMSIZE_1GB
;
170 outval
= FARADAY_PCI_MEMSIZE_2GB
;
175 outval
<<= FARADAY_PCI_MEMSIZE_SHIFT
;
177 /* This is probably not good */
178 if (mem_base
& ~(FARADAY_PCI_MEMBASE_MASK
))
179 pr_warn("truncated PCI memory base\n");
180 /* Translate to bridge side address space */
181 outval
|= (mem_base
& FARADAY_PCI_MEMBASE_MASK
);
182 pr_debug("Translated pci base @%pap, size %pap to config %08x\n",
183 &mem_base
, &mem_size
, outval
);
189 static int faraday_raw_pci_read_config(struct faraday_pci
*p
, int bus_number
,
190 unsigned int fn
, int config
, int size
,
193 writel(PCI_CONF_BUS(bus_number
) |
194 PCI_CONF_DEVICE(PCI_SLOT(fn
)) |
195 PCI_CONF_FUNCTION(PCI_FUNC(fn
)) |
196 PCI_CONF_WHERE(config
) |
198 p
->base
+ PCI_CONFIG
);
200 *value
= readl(p
->base
+ PCI_DATA
);
203 *value
= (*value
>> (8 * (config
& 3))) & 0xFF;
205 *value
= (*value
>> (8 * (config
& 3))) & 0xFFFF;
207 return PCIBIOS_SUCCESSFUL
;
210 static int faraday_pci_read_config(struct pci_bus
*bus
, unsigned int fn
,
211 int config
, int size
, u32
*value
)
213 struct faraday_pci
*p
= bus
->sysdata
;
216 "[read] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
217 PCI_SLOT(fn
), PCI_FUNC(fn
), config
, size
, *value
);
219 return faraday_raw_pci_read_config(p
, bus
->number
, fn
, config
, size
, value
);
222 static int faraday_raw_pci_write_config(struct faraday_pci
*p
, int bus_number
,
223 unsigned int fn
, int config
, int size
,
226 int ret
= PCIBIOS_SUCCESSFUL
;
228 writel(PCI_CONF_BUS(bus_number
) |
229 PCI_CONF_DEVICE(PCI_SLOT(fn
)) |
230 PCI_CONF_FUNCTION(PCI_FUNC(fn
)) |
231 PCI_CONF_WHERE(config
) |
233 p
->base
+ PCI_CONFIG
);
237 writel(value
, p
->base
+ PCI_DATA
);
240 writew(value
, p
->base
+ PCI_DATA
+ (config
& 3));
243 writeb(value
, p
->base
+ PCI_DATA
+ (config
& 3));
246 ret
= PCIBIOS_BAD_REGISTER_NUMBER
;
252 static int faraday_pci_write_config(struct pci_bus
*bus
, unsigned int fn
,
253 int config
, int size
, u32 value
)
255 struct faraday_pci
*p
= bus
->sysdata
;
258 "[write] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
259 PCI_SLOT(fn
), PCI_FUNC(fn
), config
, size
, value
);
261 return faraday_raw_pci_write_config(p
, bus
->number
, fn
, config
, size
,
265 static struct pci_ops faraday_pci_ops
= {
266 .read
= faraday_pci_read_config
,
267 .write
= faraday_pci_write_config
,
270 static void faraday_pci_ack_irq(struct irq_data
*d
)
272 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
275 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
276 reg
&= ~(0xF << PCI_CTRL2_INTSTS_SHIFT
);
277 reg
|= BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTSTS_SHIFT
);
278 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
281 static void faraday_pci_mask_irq(struct irq_data
*d
)
283 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
286 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
287 reg
&= ~((0xF << PCI_CTRL2_INTSTS_SHIFT
)
288 | BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTMASK_SHIFT
));
289 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
292 static void faraday_pci_unmask_irq(struct irq_data
*d
)
294 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
297 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
298 reg
&= ~(0xF << PCI_CTRL2_INTSTS_SHIFT
);
299 reg
|= BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTMASK_SHIFT
);
300 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
303 static void faraday_pci_irq_handler(struct irq_desc
*desc
)
305 struct faraday_pci
*p
= irq_desc_get_handler_data(desc
);
306 struct irq_chip
*irqchip
= irq_desc_get_chip(desc
);
307 unsigned int irq_stat
, reg
, i
;
309 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
310 irq_stat
= reg
>> PCI_CTRL2_INTSTS_SHIFT
;
312 chained_irq_enter(irqchip
, desc
);
314 for (i
= 0; i
< 4; i
++) {
315 if ((irq_stat
& BIT(i
)) == 0)
317 generic_handle_irq(irq_find_mapping(p
->irqdomain
, i
));
320 chained_irq_exit(irqchip
, desc
);
323 static struct irq_chip faraday_pci_irq_chip
= {
325 .irq_ack
= faraday_pci_ack_irq
,
326 .irq_mask
= faraday_pci_mask_irq
,
327 .irq_unmask
= faraday_pci_unmask_irq
,
330 static int faraday_pci_irq_map(struct irq_domain
*domain
, unsigned int irq
,
331 irq_hw_number_t hwirq
)
333 irq_set_chip_and_handler(irq
, &faraday_pci_irq_chip
, handle_level_irq
);
334 irq_set_chip_data(irq
, domain
->host_data
);
339 static const struct irq_domain_ops faraday_pci_irqdomain_ops
= {
340 .map
= faraday_pci_irq_map
,
343 static int faraday_pci_setup_cascaded_irq(struct faraday_pci
*p
)
345 struct device_node
*intc
= of_get_next_child(p
->dev
->of_node
, NULL
);
350 dev_err(p
->dev
, "missing child interrupt-controller node\n");
354 /* All PCI IRQs cascade off this one */
355 irq
= of_irq_get(intc
, 0);
357 dev_err(p
->dev
, "failed to get parent IRQ\n");
359 return irq
?: -EINVAL
;
362 p
->irqdomain
= irq_domain_add_linear(intc
, PCI_NUM_INTX
,
363 &faraday_pci_irqdomain_ops
, p
);
366 dev_err(p
->dev
, "failed to create Gemini PCI IRQ domain\n");
370 irq_set_chained_handler_and_data(irq
, faraday_pci_irq_handler
, p
);
372 for (i
= 0; i
< 4; i
++)
373 irq_create_mapping(p
->irqdomain
, i
);
378 static int faraday_pci_parse_map_dma_ranges(struct faraday_pci
*p
)
380 struct device
*dev
= p
->dev
;
381 struct pci_host_bridge
*bridge
= pci_host_bridge_from_priv(p
);
382 struct resource_entry
*entry
;
384 FARADAY_PCI_MEM1_BASE_SIZE
,
385 FARADAY_PCI_MEM2_BASE_SIZE
,
386 FARADAY_PCI_MEM3_BASE_SIZE
,
391 resource_list_for_each_entry(entry
, &bridge
->dma_ranges
) {
392 u64 pci_addr
= entry
->res
->start
- entry
->offset
;
393 u64 end
= entry
->res
->end
- entry
->offset
;
396 ret
= faraday_res_to_memcfg(pci_addr
,
397 resource_size(entry
->res
), &val
);
400 "DMA range %d: illegal MEM resource size\n", i
);
404 dev_info(dev
, "DMA MEM%d BASE: 0x%016llx -> 0x%016llx config %08x\n",
405 i
+ 1, pci_addr
, end
, val
);
407 faraday_raw_pci_write_config(p
, 0, 0, confreg
[i
],
410 dev_err(dev
, "ignore extraneous dma-range %d\n", i
);
420 static int faraday_pci_probe(struct platform_device
*pdev
)
422 struct device
*dev
= &pdev
->dev
;
423 const struct faraday_pci_variant
*variant
=
424 of_device_get_match_data(dev
);
425 struct resource_entry
*win
;
426 struct faraday_pci
*p
;
428 struct pci_host_bridge
*host
;
430 unsigned char max_bus_speed
= PCI_SPEED_33MHz
;
431 unsigned char cur_bus_speed
= PCI_SPEED_33MHz
;
435 host
= devm_pci_alloc_host_bridge(dev
, sizeof(*p
));
439 host
->ops
= &faraday_pci_ops
;
440 p
= pci_host_bridge_priv(host
);
444 /* Retrieve and enable optional clocks */
445 clk
= devm_clk_get(dev
, "PCLK");
448 ret
= clk_prepare_enable(clk
);
450 dev_err(dev
, "could not prepare PCLK\n");
453 p
->bus_clk
= devm_clk_get(dev
, "PCICLK");
454 if (IS_ERR(p
->bus_clk
))
455 return PTR_ERR(p
->bus_clk
);
456 ret
= clk_prepare_enable(p
->bus_clk
);
458 dev_err(dev
, "could not prepare PCICLK\n");
462 p
->base
= devm_platform_ioremap_resource(pdev
, 0);
464 return PTR_ERR(p
->base
);
466 win
= resource_list_first_type(&host
->windows
, IORESOURCE_IO
);
469 if (!faraday_res_to_memcfg(io
->start
- win
->offset
,
470 resource_size(io
), &val
)) {
471 /* setup I/O space size */
472 writel(val
, p
->base
+ PCI_IOSIZE
);
474 dev_err(dev
, "illegal IO mem size\n");
479 /* Setup hostbridge */
480 val
= readl(p
->base
+ PCI_CTRL
);
481 val
|= PCI_COMMAND_IO
;
482 val
|= PCI_COMMAND_MEMORY
;
483 val
|= PCI_COMMAND_MASTER
;
484 writel(val
, p
->base
+ PCI_CTRL
);
485 /* Mask and clear all interrupts */
486 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
+ 2, 2, 0xF000);
487 if (variant
->cascaded_irq
) {
488 ret
= faraday_pci_setup_cascaded_irq(p
);
490 dev_err(dev
, "failed to setup cascaded IRQ\n");
495 /* Check bus clock if we can gear up to 66 MHz */
496 if (!IS_ERR(p
->bus_clk
)) {
500 faraday_raw_pci_read_config(p
, 0, 0,
501 FARADAY_PCI_STATUS_CMD
, 4, &val
);
502 rate
= clk_get_rate(p
->bus_clk
);
504 if ((rate
== 33000000) && (val
& PCI_STATUS_66MHZ_CAPABLE
)) {
505 dev_info(dev
, "33MHz bus is 66MHz capable\n");
506 max_bus_speed
= PCI_SPEED_66MHz
;
507 ret
= clk_set_rate(p
->bus_clk
, 66000000);
509 dev_err(dev
, "failed to set bus clock\n");
511 dev_info(dev
, "33MHz only bus\n");
512 max_bus_speed
= PCI_SPEED_33MHz
;
515 /* Bumping the clock may fail so read back the rate */
516 rate
= clk_get_rate(p
->bus_clk
);
517 if (rate
== 33000000)
518 cur_bus_speed
= PCI_SPEED_33MHz
;
519 if (rate
== 66000000)
520 cur_bus_speed
= PCI_SPEED_66MHz
;
523 ret
= faraday_pci_parse_map_dma_ranges(p
);
527 ret
= pci_scan_root_bus_bridge(host
);
529 dev_err(dev
, "failed to scan host: %d\n", ret
);
533 p
->bus
->max_bus_speed
= max_bus_speed
;
534 p
->bus
->cur_bus_speed
= cur_bus_speed
;
536 pci_bus_assign_resources(p
->bus
);
537 pci_bus_add_devices(p
->bus
);
543 * We encode bridge variants here, we have at least two so it doesn't
544 * hurt to have infrastructure to encompass future variants as well.
546 static const struct faraday_pci_variant faraday_regular
= {
547 .cascaded_irq
= true,
550 static const struct faraday_pci_variant faraday_dual
= {
551 .cascaded_irq
= false,
554 static const struct of_device_id faraday_pci_of_match
[] = {
556 .compatible
= "faraday,ftpci100",
557 .data
= &faraday_regular
,
560 .compatible
= "faraday,ftpci100-dual",
561 .data
= &faraday_dual
,
566 static struct platform_driver faraday_pci_driver
= {
569 .of_match_table
= of_match_ptr(faraday_pci_of_match
),
570 .suppress_bind_attrs
= true,
572 .probe
= faraday_pci_probe
,
574 builtin_platform_driver(faraday_pci_driver
);