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>
32 * Special configuration registers directly in the first few words
35 #define PCI_IOSIZE 0x00
36 #define PCI_PROT 0x04 /* AHB protection */
37 #define PCI_CTRL 0x08 /* PCI control signal */
38 #define PCI_SOFTRST 0x10 /* Soft reset counter and response error enable */
39 #define PCI_CONFIG 0x28 /* PCI configuration command register */
42 #define FARADAY_PCI_STATUS_CMD 0x04 /* Status and command */
43 #define FARADAY_PCI_PMC 0x40 /* Power management control */
44 #define FARADAY_PCI_PMCSR 0x44 /* Power management status */
45 #define FARADAY_PCI_CTRL1 0x48 /* Control register 1 */
46 #define FARADAY_PCI_CTRL2 0x4C /* Control register 2 */
47 #define FARADAY_PCI_MEM1_BASE_SIZE 0x50 /* Memory base and size #1 */
48 #define FARADAY_PCI_MEM2_BASE_SIZE 0x54 /* Memory base and size #2 */
49 #define FARADAY_PCI_MEM3_BASE_SIZE 0x58 /* Memory base and size #3 */
51 #define PCI_STATUS_66MHZ_CAPABLE BIT(21)
53 /* Bits 31..28 gives INTD..INTA status */
54 #define PCI_CTRL2_INTSTS_SHIFT 28
55 #define PCI_CTRL2_INTMASK_CMDERR BIT(27)
56 #define PCI_CTRL2_INTMASK_PARERR BIT(26)
57 /* Bits 25..22 masks INTD..INTA */
58 #define PCI_CTRL2_INTMASK_SHIFT 22
59 #define PCI_CTRL2_INTMASK_MABRT_RX BIT(21)
60 #define PCI_CTRL2_INTMASK_TABRT_RX BIT(20)
61 #define PCI_CTRL2_INTMASK_TABRT_TX BIT(19)
62 #define PCI_CTRL2_INTMASK_RETRY4 BIT(18)
63 #define PCI_CTRL2_INTMASK_SERR_RX BIT(17)
64 #define PCI_CTRL2_INTMASK_PERR_RX BIT(16)
66 #define PCI_CTRL2_MSTPRI_REQ6 BIT(14)
67 #define PCI_CTRL2_MSTPRI_REQ5 BIT(13)
68 #define PCI_CTRL2_MSTPRI_REQ4 BIT(12)
69 #define PCI_CTRL2_MSTPRI_REQ3 BIT(11)
70 #define PCI_CTRL2_MSTPRI_REQ2 BIT(10)
71 #define PCI_CTRL2_MSTPRI_REQ1 BIT(9)
72 #define PCI_CTRL2_MSTPRI_REQ0 BIT(8)
73 /* Bits 7..4 reserved */
78 * Bit 31..20 defines the PCI side memory base
79 * Bit 19..16 (4 bits) defines the size per below
81 #define FARADAY_PCI_MEMBASE_MASK 0xfff00000
82 #define FARADAY_PCI_MEMSIZE_1MB 0x0
83 #define FARADAY_PCI_MEMSIZE_2MB 0x1
84 #define FARADAY_PCI_MEMSIZE_4MB 0x2
85 #define FARADAY_PCI_MEMSIZE_8MB 0x3
86 #define FARADAY_PCI_MEMSIZE_16MB 0x4
87 #define FARADAY_PCI_MEMSIZE_32MB 0x5
88 #define FARADAY_PCI_MEMSIZE_64MB 0x6
89 #define FARADAY_PCI_MEMSIZE_128MB 0x7
90 #define FARADAY_PCI_MEMSIZE_256MB 0x8
91 #define FARADAY_PCI_MEMSIZE_512MB 0x9
92 #define FARADAY_PCI_MEMSIZE_1GB 0xa
93 #define FARADAY_PCI_MEMSIZE_2GB 0xb
94 #define FARADAY_PCI_MEMSIZE_SHIFT 16
97 * The DMA base is set to 0x0 for all memory segments, it reflects the
98 * fact that the memory of the host system starts at 0x0.
100 #define FARADAY_PCI_DMA_MEM1_BASE 0x00000000
101 #define FARADAY_PCI_DMA_MEM2_BASE 0x00000000
102 #define FARADAY_PCI_DMA_MEM3_BASE 0x00000000
104 /* Defines for PCI configuration command register */
105 #define PCI_CONF_ENABLE BIT(31)
106 #define PCI_CONF_WHERE(r) ((r) & 0xFC)
107 #define PCI_CONF_BUS(b) (((b) & 0xFF) << 16)
108 #define PCI_CONF_DEVICE(d) (((d) & 0x1F) << 11)
109 #define PCI_CONF_FUNCTION(f) (((f) & 0x07) << 8)
112 * struct faraday_pci_variant - encodes IP block differences
113 * @cascaded_irq: this host has cascaded IRQs from an interrupt controller
114 * embedded in the host bridge.
116 struct faraday_pci_variant
{
123 struct irq_domain
*irqdomain
;
128 static int faraday_res_to_memcfg(resource_size_t mem_base
,
129 resource_size_t mem_size
, u32
*val
)
135 outval
= FARADAY_PCI_MEMSIZE_1MB
;
138 outval
= FARADAY_PCI_MEMSIZE_2MB
;
141 outval
= FARADAY_PCI_MEMSIZE_4MB
;
144 outval
= FARADAY_PCI_MEMSIZE_8MB
;
147 outval
= FARADAY_PCI_MEMSIZE_16MB
;
150 outval
= FARADAY_PCI_MEMSIZE_32MB
;
153 outval
= FARADAY_PCI_MEMSIZE_64MB
;
156 outval
= FARADAY_PCI_MEMSIZE_128MB
;
159 outval
= FARADAY_PCI_MEMSIZE_256MB
;
162 outval
= FARADAY_PCI_MEMSIZE_512MB
;
165 outval
= FARADAY_PCI_MEMSIZE_1GB
;
168 outval
= FARADAY_PCI_MEMSIZE_2GB
;
173 outval
<<= FARADAY_PCI_MEMSIZE_SHIFT
;
175 /* This is probably not good */
176 if (mem_base
& ~(FARADAY_PCI_MEMBASE_MASK
))
177 pr_warn("truncated PCI memory base\n");
178 /* Translate to bridge side address space */
179 outval
|= (mem_base
& FARADAY_PCI_MEMBASE_MASK
);
180 pr_debug("Translated pci base @%pap, size %pap to config %08x\n",
181 &mem_base
, &mem_size
, outval
);
187 static int faraday_raw_pci_read_config(struct faraday_pci
*p
, int bus_number
,
188 unsigned int fn
, int config
, int size
,
191 writel(PCI_CONF_BUS(bus_number
) |
192 PCI_CONF_DEVICE(PCI_SLOT(fn
)) |
193 PCI_CONF_FUNCTION(PCI_FUNC(fn
)) |
194 PCI_CONF_WHERE(config
) |
196 p
->base
+ PCI_CONFIG
);
198 *value
= readl(p
->base
+ PCI_DATA
);
201 *value
= (*value
>> (8 * (config
& 3))) & 0xFF;
203 *value
= (*value
>> (8 * (config
& 3))) & 0xFFFF;
205 return PCIBIOS_SUCCESSFUL
;
208 static int faraday_pci_read_config(struct pci_bus
*bus
, unsigned int fn
,
209 int config
, int size
, u32
*value
)
211 struct faraday_pci
*p
= bus
->sysdata
;
214 "[read] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
215 PCI_SLOT(fn
), PCI_FUNC(fn
), config
, size
, *value
);
217 return faraday_raw_pci_read_config(p
, bus
->number
, fn
, config
, size
, value
);
220 static int faraday_raw_pci_write_config(struct faraday_pci
*p
, int bus_number
,
221 unsigned int fn
, int config
, int size
,
224 int ret
= PCIBIOS_SUCCESSFUL
;
226 writel(PCI_CONF_BUS(bus_number
) |
227 PCI_CONF_DEVICE(PCI_SLOT(fn
)) |
228 PCI_CONF_FUNCTION(PCI_FUNC(fn
)) |
229 PCI_CONF_WHERE(config
) |
231 p
->base
+ PCI_CONFIG
);
235 writel(value
, p
->base
+ PCI_DATA
);
238 writew(value
, p
->base
+ PCI_DATA
+ (config
& 3));
241 writeb(value
, p
->base
+ PCI_DATA
+ (config
& 3));
244 ret
= PCIBIOS_BAD_REGISTER_NUMBER
;
250 static int faraday_pci_write_config(struct pci_bus
*bus
, unsigned int fn
,
251 int config
, int size
, u32 value
)
253 struct faraday_pci
*p
= bus
->sysdata
;
256 "[write] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
257 PCI_SLOT(fn
), PCI_FUNC(fn
), config
, size
, value
);
259 return faraday_raw_pci_write_config(p
, bus
->number
, fn
, config
, size
,
263 static struct pci_ops faraday_pci_ops
= {
264 .read
= faraday_pci_read_config
,
265 .write
= faraday_pci_write_config
,
268 static void faraday_pci_ack_irq(struct irq_data
*d
)
270 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
273 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
274 reg
&= ~(0xF << PCI_CTRL2_INTSTS_SHIFT
);
275 reg
|= BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTSTS_SHIFT
);
276 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
279 static void faraday_pci_mask_irq(struct irq_data
*d
)
281 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
284 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
285 reg
&= ~((0xF << PCI_CTRL2_INTSTS_SHIFT
)
286 | BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTMASK_SHIFT
));
287 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
290 static void faraday_pci_unmask_irq(struct irq_data
*d
)
292 struct faraday_pci
*p
= irq_data_get_irq_chip_data(d
);
295 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
296 reg
&= ~(0xF << PCI_CTRL2_INTSTS_SHIFT
);
297 reg
|= BIT(irqd_to_hwirq(d
) + PCI_CTRL2_INTMASK_SHIFT
);
298 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, reg
);
301 static void faraday_pci_irq_handler(struct irq_desc
*desc
)
303 struct faraday_pci
*p
= irq_desc_get_handler_data(desc
);
304 struct irq_chip
*irqchip
= irq_desc_get_chip(desc
);
305 unsigned int irq_stat
, reg
, i
;
307 faraday_raw_pci_read_config(p
, 0, 0, FARADAY_PCI_CTRL2
, 4, ®
);
308 irq_stat
= reg
>> PCI_CTRL2_INTSTS_SHIFT
;
310 chained_irq_enter(irqchip
, desc
);
312 for (i
= 0; i
< 4; i
++) {
313 if ((irq_stat
& BIT(i
)) == 0)
315 generic_handle_irq(irq_find_mapping(p
->irqdomain
, i
));
318 chained_irq_exit(irqchip
, desc
);
321 static struct irq_chip faraday_pci_irq_chip
= {
323 .irq_ack
= faraday_pci_ack_irq
,
324 .irq_mask
= faraday_pci_mask_irq
,
325 .irq_unmask
= faraday_pci_unmask_irq
,
328 static int faraday_pci_irq_map(struct irq_domain
*domain
, unsigned int irq
,
329 irq_hw_number_t hwirq
)
331 irq_set_chip_and_handler(irq
, &faraday_pci_irq_chip
, handle_level_irq
);
332 irq_set_chip_data(irq
, domain
->host_data
);
337 static const struct irq_domain_ops faraday_pci_irqdomain_ops
= {
338 .map
= faraday_pci_irq_map
,
341 static int faraday_pci_setup_cascaded_irq(struct faraday_pci
*p
)
343 struct device_node
*intc
= of_get_next_child(p
->dev
->of_node
, NULL
);
348 dev_err(p
->dev
, "missing child interrupt-controller node\n");
352 /* All PCI IRQs cascade off this one */
353 irq
= of_irq_get(intc
, 0);
355 dev_err(p
->dev
, "failed to get parent IRQ\n");
356 return irq
?: -EINVAL
;
359 p
->irqdomain
= irq_domain_add_linear(intc
, PCI_NUM_INTX
,
360 &faraday_pci_irqdomain_ops
, p
);
362 dev_err(p
->dev
, "failed to create Gemini PCI IRQ domain\n");
366 irq_set_chained_handler_and_data(irq
, faraday_pci_irq_handler
, p
);
368 for (i
= 0; i
< 4; i
++)
369 irq_create_mapping(p
->irqdomain
, i
);
374 static int faraday_pci_parse_map_dma_ranges(struct faraday_pci
*p
,
375 struct device_node
*np
)
377 struct of_pci_range range
;
378 struct of_pci_range_parser parser
;
379 struct device
*dev
= p
->dev
;
381 FARADAY_PCI_MEM1_BASE_SIZE
,
382 FARADAY_PCI_MEM2_BASE_SIZE
,
383 FARADAY_PCI_MEM3_BASE_SIZE
,
388 if (of_pci_dma_range_parser_init(&parser
, np
)) {
389 dev_err(dev
, "missing dma-ranges property\n");
394 * Get the dma-ranges from the device tree
396 for_each_of_pci_range(&parser
, &range
) {
397 u64 end
= range
.pci_addr
+ range
.size
- 1;
400 ret
= faraday_res_to_memcfg(range
.pci_addr
, range
.size
, &val
);
403 "DMA range %d: illegal MEM resource size\n", i
);
407 dev_info(dev
, "DMA MEM%d BASE: 0x%016llx -> 0x%016llx config %08x\n",
408 i
+ 1, range
.pci_addr
, end
, val
);
410 faraday_raw_pci_write_config(p
, 0, 0, confreg
[i
],
413 dev_err(dev
, "ignore extraneous dma-range %d\n", i
);
423 static int faraday_pci_probe(struct platform_device
*pdev
)
425 struct device
*dev
= &pdev
->dev
;
426 const struct faraday_pci_variant
*variant
=
427 of_device_get_match_data(dev
);
428 struct resource
*regs
;
429 resource_size_t io_base
;
430 struct resource_entry
*win
;
431 struct faraday_pci
*p
;
432 struct resource
*mem
;
434 struct pci_host_bridge
*host
;
436 unsigned char max_bus_speed
= PCI_SPEED_33MHz
;
437 unsigned char cur_bus_speed
= PCI_SPEED_33MHz
;
442 host
= devm_pci_alloc_host_bridge(dev
, sizeof(*p
));
446 host
->dev
.parent
= dev
;
447 host
->ops
= &faraday_pci_ops
;
450 host
->map_irq
= of_irq_parse_and_map_pci
;
451 host
->swizzle_irq
= pci_common_swizzle
;
452 p
= pci_host_bridge_priv(host
);
456 /* Retrieve and enable optional clocks */
457 clk
= devm_clk_get(dev
, "PCLK");
460 ret
= clk_prepare_enable(clk
);
462 dev_err(dev
, "could not prepare PCLK\n");
465 p
->bus_clk
= devm_clk_get(dev
, "PCICLK");
466 if (IS_ERR(p
->bus_clk
))
467 return PTR_ERR(p
->bus_clk
);
468 ret
= clk_prepare_enable(p
->bus_clk
);
470 dev_err(dev
, "could not prepare PCICLK\n");
474 regs
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
475 p
->base
= devm_ioremap_resource(dev
, regs
);
477 return PTR_ERR(p
->base
);
479 ret
= of_pci_get_host_bridge_resources(dev
->of_node
, 0, 0xff,
484 ret
= devm_request_pci_bus_resources(dev
, &res
);
488 /* Get the I/O and memory ranges from DT */
489 resource_list_for_each_entry(win
, &res
) {
490 switch (resource_type(win
->res
)) {
493 io
->name
= "Gemini PCI I/O";
494 if (!faraday_res_to_memcfg(io
->start
- win
->offset
,
495 resource_size(io
), &val
)) {
496 /* setup I/O space size */
497 writel(val
, p
->base
+ PCI_IOSIZE
);
499 dev_err(dev
, "illegal IO mem size\n");
502 ret
= pci_remap_iospace(io
, io_base
);
504 dev_warn(dev
, "error %d: failed to map resource %pR\n",
511 mem
->name
= "Gemini PCI MEM";
520 /* Setup hostbridge */
521 val
= readl(p
->base
+ PCI_CTRL
);
522 val
|= PCI_COMMAND_IO
;
523 val
|= PCI_COMMAND_MEMORY
;
524 val
|= PCI_COMMAND_MASTER
;
525 writel(val
, p
->base
+ PCI_CTRL
);
526 /* Mask and clear all interrupts */
527 faraday_raw_pci_write_config(p
, 0, 0, FARADAY_PCI_CTRL2
+ 2, 2, 0xF000);
528 if (variant
->cascaded_irq
) {
529 ret
= faraday_pci_setup_cascaded_irq(p
);
531 dev_err(dev
, "failed to setup cascaded IRQ\n");
536 /* Check bus clock if we can gear up to 66 MHz */
537 if (!IS_ERR(p
->bus_clk
)) {
541 faraday_raw_pci_read_config(p
, 0, 0,
542 FARADAY_PCI_STATUS_CMD
, 4, &val
);
543 rate
= clk_get_rate(p
->bus_clk
);
545 if ((rate
== 33000000) && (val
& PCI_STATUS_66MHZ_CAPABLE
)) {
546 dev_info(dev
, "33MHz bus is 66MHz capable\n");
547 max_bus_speed
= PCI_SPEED_66MHz
;
548 ret
= clk_set_rate(p
->bus_clk
, 66000000);
550 dev_err(dev
, "failed to set bus clock\n");
552 dev_info(dev
, "33MHz only bus\n");
553 max_bus_speed
= PCI_SPEED_33MHz
;
556 /* Bumping the clock may fail so read back the rate */
557 rate
= clk_get_rate(p
->bus_clk
);
558 if (rate
== 33000000)
559 cur_bus_speed
= PCI_SPEED_33MHz
;
560 if (rate
== 66000000)
561 cur_bus_speed
= PCI_SPEED_66MHz
;
564 ret
= faraday_pci_parse_map_dma_ranges(p
, dev
->of_node
);
568 list_splice_init(&res
, &host
->windows
);
569 ret
= pci_scan_root_bus_bridge(host
);
571 dev_err(dev
, "failed to scan host: %d\n", ret
);
575 p
->bus
->max_bus_speed
= max_bus_speed
;
576 p
->bus
->cur_bus_speed
= cur_bus_speed
;
578 pci_bus_assign_resources(p
->bus
);
579 pci_bus_add_devices(p
->bus
);
580 pci_free_resource_list(&res
);
586 * We encode bridge variants here, we have at least two so it doesn't
587 * hurt to have infrastructure to encompass future variants as well.
589 const struct faraday_pci_variant faraday_regular
= {
590 .cascaded_irq
= true,
593 const struct faraday_pci_variant faraday_dual
= {
594 .cascaded_irq
= false,
597 static const struct of_device_id faraday_pci_of_match
[] = {
599 .compatible
= "faraday,ftpci100",
600 .data
= &faraday_regular
,
603 .compatible
= "faraday,ftpci100-dual",
604 .data
= &faraday_dual
,
609 static struct platform_driver faraday_pci_driver
= {
612 .of_match_table
= of_match_ptr(faraday_pci_of_match
),
613 .suppress_bind_attrs
= true,
615 .probe
= faraday_pci_probe
,
617 builtin_platform_driver(faraday_pci_driver
);