1 // SPDX-License-Identifier: GPL-2.0+
3 * PCIe host controller driver for Xilinx Versal CPM DMA Bridge
5 * (C) Copyright 2019 - 2020, Xilinx, Inc.
8 #include <linux/bitfield.h>
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/irqchip.h>
12 #include <linux/irqchip/chained_irq.h>
13 #include <linux/irqdomain.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of_address.h>
17 #include <linux/of_pci.h>
18 #include <linux/of_platform.h>
19 #include <linux/of_irq.h>
20 #include <linux/pci.h>
21 #include <linux/platform_device.h>
22 #include <linux/pci-ecam.h>
26 /* Register definitions */
27 #define XILINX_CPM_PCIE_REG_IDR 0x00000E10
28 #define XILINX_CPM_PCIE_REG_IMR 0x00000E14
29 #define XILINX_CPM_PCIE_REG_PSCR 0x00000E1C
30 #define XILINX_CPM_PCIE_REG_RPSC 0x00000E20
31 #define XILINX_CPM_PCIE_REG_RPEFR 0x00000E2C
32 #define XILINX_CPM_PCIE_REG_IDRN 0x00000E38
33 #define XILINX_CPM_PCIE_REG_IDRN_MASK 0x00000E3C
34 #define XILINX_CPM_PCIE_MISC_IR_STATUS 0x00000340
35 #define XILINX_CPM_PCIE_MISC_IR_ENABLE 0x00000348
36 #define XILINX_CPM_PCIE_MISC_IR_LOCAL BIT(1)
38 /* Interrupt registers definitions */
39 #define XILINX_CPM_PCIE_INTR_LINK_DOWN 0
40 #define XILINX_CPM_PCIE_INTR_HOT_RESET 3
41 #define XILINX_CPM_PCIE_INTR_CFG_PCIE_TIMEOUT 4
42 #define XILINX_CPM_PCIE_INTR_CFG_TIMEOUT 8
43 #define XILINX_CPM_PCIE_INTR_CORRECTABLE 9
44 #define XILINX_CPM_PCIE_INTR_NONFATAL 10
45 #define XILINX_CPM_PCIE_INTR_FATAL 11
46 #define XILINX_CPM_PCIE_INTR_CFG_ERR_POISON 12
47 #define XILINX_CPM_PCIE_INTR_PME_TO_ACK_RCVD 15
48 #define XILINX_CPM_PCIE_INTR_INTX 16
49 #define XILINX_CPM_PCIE_INTR_PM_PME_RCVD 17
50 #define XILINX_CPM_PCIE_INTR_SLV_UNSUPP 20
51 #define XILINX_CPM_PCIE_INTR_SLV_UNEXP 21
52 #define XILINX_CPM_PCIE_INTR_SLV_COMPL 22
53 #define XILINX_CPM_PCIE_INTR_SLV_ERRP 23
54 #define XILINX_CPM_PCIE_INTR_SLV_CMPABT 24
55 #define XILINX_CPM_PCIE_INTR_SLV_ILLBUR 25
56 #define XILINX_CPM_PCIE_INTR_MST_DECERR 26
57 #define XILINX_CPM_PCIE_INTR_MST_SLVERR 27
58 #define XILINX_CPM_PCIE_INTR_SLV_PCIE_TIMEOUT 28
60 #define IMR(x) BIT(XILINX_CPM_PCIE_INTR_ ##x)
62 #define XILINX_CPM_PCIE_IMR_ALL_MASK \
66 IMR(CFG_PCIE_TIMEOUT) | \
71 IMR(CFG_ERR_POISON) | \
72 IMR(PME_TO_ACK_RCVD) | \
83 IMR(SLV_PCIE_TIMEOUT) \
86 #define XILINX_CPM_PCIE_IDR_ALL_MASK 0xFFFFFFFF
87 #define XILINX_CPM_PCIE_IDRN_MASK GENMASK(19, 16)
88 #define XILINX_CPM_PCIE_IDRN_SHIFT 16
90 /* Root Port Error FIFO Read Register definitions */
91 #define XILINX_CPM_PCIE_RPEFR_ERR_VALID BIT(18)
92 #define XILINX_CPM_PCIE_RPEFR_REQ_ID GENMASK(15, 0)
93 #define XILINX_CPM_PCIE_RPEFR_ALL_MASK 0xFFFFFFFF
95 /* Root Port Status/control Register definitions */
96 #define XILINX_CPM_PCIE_REG_RPSC_BEN BIT(0)
98 /* Phy Status/Control Register definitions */
99 #define XILINX_CPM_PCIE_REG_PSCR_LNKUP BIT(11)
102 * struct xilinx_cpm_pcie_port - PCIe port information
103 * @reg_base: Bridge Register Base
104 * @cpm_base: CPM System Level Control and Status Register(SLCR) Base
105 * @dev: Device pointer
106 * @intx_domain: Legacy IRQ domain pointer
107 * @cpm_domain: CPM IRQ domain pointer
108 * @cfg: Holds mappings of config space window
109 * @intx_irq: legacy interrupt number
110 * @irq: Error interrupt number
111 * @lock: lock protecting shared register access
113 struct xilinx_cpm_pcie_port {
114 void __iomem *reg_base;
115 void __iomem *cpm_base;
117 struct irq_domain *intx_domain;
118 struct irq_domain *cpm_domain;
119 struct pci_config_window *cfg;
125 static u32 pcie_read(struct xilinx_cpm_pcie_port *port, u32 reg)
127 return readl_relaxed(port->reg_base + reg);
130 static void pcie_write(struct xilinx_cpm_pcie_port *port,
133 writel_relaxed(val, port->reg_base + reg);
136 static bool cpm_pcie_link_up(struct xilinx_cpm_pcie_port *port)
138 return (pcie_read(port, XILINX_CPM_PCIE_REG_PSCR) &
139 XILINX_CPM_PCIE_REG_PSCR_LNKUP);
142 static void cpm_pcie_clear_err_interrupts(struct xilinx_cpm_pcie_port *port)
144 unsigned long val = pcie_read(port, XILINX_CPM_PCIE_REG_RPEFR);
146 if (val & XILINX_CPM_PCIE_RPEFR_ERR_VALID) {
147 dev_dbg(port->dev, "Requester ID %lu\n",
148 val & XILINX_CPM_PCIE_RPEFR_REQ_ID);
149 pcie_write(port, XILINX_CPM_PCIE_RPEFR_ALL_MASK,
150 XILINX_CPM_PCIE_REG_RPEFR);
154 static void xilinx_cpm_mask_leg_irq(struct irq_data *data)
156 struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(data);
161 mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
162 raw_spin_lock_irqsave(&port->lock, flags);
163 val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
164 pcie_write(port, (val & (~mask)), XILINX_CPM_PCIE_REG_IDRN_MASK);
165 raw_spin_unlock_irqrestore(&port->lock, flags);
168 static void xilinx_cpm_unmask_leg_irq(struct irq_data *data)
170 struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(data);
175 mask = BIT(data->hwirq + XILINX_CPM_PCIE_IDRN_SHIFT);
176 raw_spin_lock_irqsave(&port->lock, flags);
177 val = pcie_read(port, XILINX_CPM_PCIE_REG_IDRN_MASK);
178 pcie_write(port, (val | mask), XILINX_CPM_PCIE_REG_IDRN_MASK);
179 raw_spin_unlock_irqrestore(&port->lock, flags);
182 static struct irq_chip xilinx_cpm_leg_irq_chip = {
184 .irq_mask = xilinx_cpm_mask_leg_irq,
185 .irq_unmask = xilinx_cpm_unmask_leg_irq,
189 * xilinx_cpm_pcie_intx_map - Set the handler for the INTx and mark IRQ as valid
190 * @domain: IRQ domain
191 * @irq: Virtual IRQ number
192 * @hwirq: HW interrupt number
194 * Return: Always returns 0.
196 static int xilinx_cpm_pcie_intx_map(struct irq_domain *domain,
197 unsigned int irq, irq_hw_number_t hwirq)
199 irq_set_chip_and_handler(irq, &xilinx_cpm_leg_irq_chip,
201 irq_set_chip_data(irq, domain->host_data);
202 irq_set_status_flags(irq, IRQ_LEVEL);
207 /* INTx IRQ Domain operations */
208 static const struct irq_domain_ops intx_domain_ops = {
209 .map = xilinx_cpm_pcie_intx_map,
212 static void xilinx_cpm_pcie_intx_flow(struct irq_desc *desc)
214 struct xilinx_cpm_pcie_port *port = irq_desc_get_handler_data(desc);
215 struct irq_chip *chip = irq_desc_get_chip(desc);
219 chained_irq_enter(chip, desc);
221 val = FIELD_GET(XILINX_CPM_PCIE_IDRN_MASK,
222 pcie_read(port, XILINX_CPM_PCIE_REG_IDRN));
224 for_each_set_bit(i, &val, PCI_NUM_INTX)
225 generic_handle_irq(irq_find_mapping(port->intx_domain, i));
227 chained_irq_exit(chip, desc);
230 static void xilinx_cpm_mask_event_irq(struct irq_data *d)
232 struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(d);
235 raw_spin_lock(&port->lock);
236 val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
237 val &= ~BIT(d->hwirq);
238 pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
239 raw_spin_unlock(&port->lock);
242 static void xilinx_cpm_unmask_event_irq(struct irq_data *d)
244 struct xilinx_cpm_pcie_port *port = irq_data_get_irq_chip_data(d);
247 raw_spin_lock(&port->lock);
248 val = pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
249 val |= BIT(d->hwirq);
250 pcie_write(port, val, XILINX_CPM_PCIE_REG_IMR);
251 raw_spin_unlock(&port->lock);
254 static struct irq_chip xilinx_cpm_event_irq_chip = {
256 .irq_mask = xilinx_cpm_mask_event_irq,
257 .irq_unmask = xilinx_cpm_unmask_event_irq,
260 static int xilinx_cpm_pcie_event_map(struct irq_domain *domain,
261 unsigned int irq, irq_hw_number_t hwirq)
263 irq_set_chip_and_handler(irq, &xilinx_cpm_event_irq_chip,
265 irq_set_chip_data(irq, domain->host_data);
266 irq_set_status_flags(irq, IRQ_LEVEL);
270 static const struct irq_domain_ops event_domain_ops = {
271 .map = xilinx_cpm_pcie_event_map,
274 static void xilinx_cpm_pcie_event_flow(struct irq_desc *desc)
276 struct xilinx_cpm_pcie_port *port = irq_desc_get_handler_data(desc);
277 struct irq_chip *chip = irq_desc_get_chip(desc);
281 chained_irq_enter(chip, desc);
282 val = pcie_read(port, XILINX_CPM_PCIE_REG_IDR);
283 val &= pcie_read(port, XILINX_CPM_PCIE_REG_IMR);
284 for_each_set_bit(i, &val, 32)
285 generic_handle_irq(irq_find_mapping(port->cpm_domain, i));
286 pcie_write(port, val, XILINX_CPM_PCIE_REG_IDR);
289 * XILINX_CPM_PCIE_MISC_IR_STATUS register is mapped to
292 val = readl_relaxed(port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
295 port->cpm_base + XILINX_CPM_PCIE_MISC_IR_STATUS);
297 chained_irq_exit(chip, desc);
301 [XILINX_CPM_PCIE_INTR_ ## x] = { __stringify(x), s }
303 static const struct {
307 _IC(LINK_DOWN, "Link Down"),
308 _IC(HOT_RESET, "Hot reset"),
309 _IC(CFG_TIMEOUT, "ECAM access timeout"),
310 _IC(CORRECTABLE, "Correctable error message"),
311 _IC(NONFATAL, "Non fatal error message"),
312 _IC(FATAL, "Fatal error message"),
313 _IC(SLV_UNSUPP, "Slave unsupported request"),
314 _IC(SLV_UNEXP, "Slave unexpected completion"),
315 _IC(SLV_COMPL, "Slave completion timeout"),
316 _IC(SLV_ERRP, "Slave Error Poison"),
317 _IC(SLV_CMPABT, "Slave Completer Abort"),
318 _IC(SLV_ILLBUR, "Slave Illegal Burst"),
319 _IC(MST_DECERR, "Master decode error"),
320 _IC(MST_SLVERR, "Master slave error"),
321 _IC(CFG_PCIE_TIMEOUT, "PCIe ECAM access timeout"),
322 _IC(CFG_ERR_POISON, "ECAM poisoned completion received"),
323 _IC(PME_TO_ACK_RCVD, "PME_TO_ACK message received"),
324 _IC(PM_PME_RCVD, "PM_PME message received"),
325 _IC(SLV_PCIE_TIMEOUT, "PCIe completion timeout received"),
328 static irqreturn_t xilinx_cpm_pcie_intr_handler(int irq, void *dev_id)
330 struct xilinx_cpm_pcie_port *port = dev_id;
331 struct device *dev = port->dev;
334 d = irq_domain_get_irq_data(port->cpm_domain, irq);
337 case XILINX_CPM_PCIE_INTR_CORRECTABLE:
338 case XILINX_CPM_PCIE_INTR_NONFATAL:
339 case XILINX_CPM_PCIE_INTR_FATAL:
340 cpm_pcie_clear_err_interrupts(port);
344 if (intr_cause[d->hwirq].str)
345 dev_warn(dev, "%s\n", intr_cause[d->hwirq].str);
347 dev_warn(dev, "Unknown IRQ %ld\n", d->hwirq);
353 static void xilinx_cpm_free_irq_domains(struct xilinx_cpm_pcie_port *port)
355 if (port->intx_domain) {
356 irq_domain_remove(port->intx_domain);
357 port->intx_domain = NULL;
360 if (port->cpm_domain) {
361 irq_domain_remove(port->cpm_domain);
362 port->cpm_domain = NULL;
367 * xilinx_cpm_pcie_init_irq_domain - Initialize IRQ domain
368 * @port: PCIe port information
370 * Return: '0' on success and error value on failure
372 static int xilinx_cpm_pcie_init_irq_domain(struct xilinx_cpm_pcie_port *port)
374 struct device *dev = port->dev;
375 struct device_node *node = dev->of_node;
376 struct device_node *pcie_intc_node;
379 pcie_intc_node = of_get_next_child(node, NULL);
380 if (!pcie_intc_node) {
381 dev_err(dev, "No PCIe Intc node found\n");
385 port->cpm_domain = irq_domain_add_linear(pcie_intc_node, 32,
388 if (!port->cpm_domain)
391 irq_domain_update_bus_token(port->cpm_domain, DOMAIN_BUS_NEXUS);
393 port->intx_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
396 if (!port->intx_domain)
399 irq_domain_update_bus_token(port->intx_domain, DOMAIN_BUS_WIRED);
401 of_node_put(pcie_intc_node);
402 raw_spin_lock_init(&port->lock);
406 xilinx_cpm_free_irq_domains(port);
407 dev_err(dev, "Failed to allocate IRQ domains\n");
412 static int xilinx_cpm_setup_irq(struct xilinx_cpm_pcie_port *port)
414 struct device *dev = port->dev;
415 struct platform_device *pdev = to_platform_device(dev);
418 port->irq = platform_get_irq(pdev, 0);
422 for (i = 0; i < ARRAY_SIZE(intr_cause); i++) {
425 if (!intr_cause[i].str)
428 irq = irq_create_mapping(port->cpm_domain, i);
430 dev_err(dev, "Failed to map interrupt\n");
434 err = devm_request_irq(dev, irq, xilinx_cpm_pcie_intr_handler,
435 0, intr_cause[i].sym, port);
437 dev_err(dev, "Failed to request IRQ %d\n", irq);
442 port->intx_irq = irq_create_mapping(port->cpm_domain,
443 XILINX_CPM_PCIE_INTR_INTX);
444 if (!port->intx_irq) {
445 dev_err(dev, "Failed to map INTx interrupt\n");
449 /* Plug the INTx chained handler */
450 irq_set_chained_handler_and_data(port->intx_irq,
451 xilinx_cpm_pcie_intx_flow, port);
453 /* Plug the main event chained handler */
454 irq_set_chained_handler_and_data(port->irq,
455 xilinx_cpm_pcie_event_flow, port);
461 * xilinx_cpm_pcie_init_port - Initialize hardware
462 * @port: PCIe port information
464 static void xilinx_cpm_pcie_init_port(struct xilinx_cpm_pcie_port *port)
466 if (cpm_pcie_link_up(port))
467 dev_info(port->dev, "PCIe Link is UP\n");
469 dev_info(port->dev, "PCIe Link is DOWN\n");
471 /* Disable all interrupts */
472 pcie_write(port, ~XILINX_CPM_PCIE_IDR_ALL_MASK,
473 XILINX_CPM_PCIE_REG_IMR);
475 /* Clear pending interrupts */
476 pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_IDR) &
477 XILINX_CPM_PCIE_IMR_ALL_MASK,
478 XILINX_CPM_PCIE_REG_IDR);
481 * XILINX_CPM_PCIE_MISC_IR_ENABLE register is mapped to
484 writel(XILINX_CPM_PCIE_MISC_IR_LOCAL,
485 port->cpm_base + XILINX_CPM_PCIE_MISC_IR_ENABLE);
486 /* Enable the Bridge enable bit */
487 pcie_write(port, pcie_read(port, XILINX_CPM_PCIE_REG_RPSC) |
488 XILINX_CPM_PCIE_REG_RPSC_BEN,
489 XILINX_CPM_PCIE_REG_RPSC);
493 * xilinx_cpm_pcie_parse_dt - Parse Device tree
494 * @port: PCIe port information
495 * @bus_range: Bus resource
497 * Return: '0' on success and error value on failure
499 static int xilinx_cpm_pcie_parse_dt(struct xilinx_cpm_pcie_port *port,
500 struct resource *bus_range)
502 struct device *dev = port->dev;
503 struct platform_device *pdev = to_platform_device(dev);
504 struct resource *res;
506 port->cpm_base = devm_platform_ioremap_resource_byname(pdev,
508 if (IS_ERR(port->cpm_base))
509 return PTR_ERR(port->cpm_base);
511 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
515 port->cfg = pci_ecam_create(dev, res, bus_range,
516 &pci_generic_ecam_ops);
517 if (IS_ERR(port->cfg))
518 return PTR_ERR(port->cfg);
520 port->reg_base = port->cfg->win;
525 static void xilinx_cpm_free_interrupts(struct xilinx_cpm_pcie_port *port)
527 irq_set_chained_handler_and_data(port->intx_irq, NULL, NULL);
528 irq_set_chained_handler_and_data(port->irq, NULL, NULL);
532 * xilinx_cpm_pcie_probe - Probe function
533 * @pdev: Platform device pointer
535 * Return: '0' on success and error value on failure
537 static int xilinx_cpm_pcie_probe(struct platform_device *pdev)
539 struct xilinx_cpm_pcie_port *port;
540 struct device *dev = &pdev->dev;
541 struct pci_host_bridge *bridge;
542 struct resource_entry *bus;
545 bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
549 port = pci_host_bridge_priv(bridge);
553 err = xilinx_cpm_pcie_init_irq_domain(port);
557 bus = resource_list_first_type(&bridge->windows, IORESOURCE_BUS);
561 err = xilinx_cpm_pcie_parse_dt(port, bus->res);
563 dev_err(dev, "Parsing DT failed\n");
567 xilinx_cpm_pcie_init_port(port);
569 err = xilinx_cpm_setup_irq(port);
571 dev_err(dev, "Failed to set up interrupts\n");
575 bridge->dev.parent = dev;
576 bridge->sysdata = port->cfg;
577 bridge->busnr = port->cfg->busr.start;
578 bridge->ops = (struct pci_ops *)&pci_generic_ecam_ops.pci_ops;
579 bridge->map_irq = of_irq_parse_and_map_pci;
580 bridge->swizzle_irq = pci_common_swizzle;
582 err = pci_host_probe(bridge);
584 goto err_host_bridge;
589 xilinx_cpm_free_interrupts(port);
591 pci_ecam_free(port->cfg);
593 xilinx_cpm_free_irq_domains(port);
597 static const struct of_device_id xilinx_cpm_pcie_of_match[] = {
598 { .compatible = "xlnx,versal-cpm-host-1.00", },
602 static struct platform_driver xilinx_cpm_pcie_driver = {
604 .name = "xilinx-cpm-pcie",
605 .of_match_table = xilinx_cpm_pcie_of_match,
606 .suppress_bind_attrs = true,
608 .probe = xilinx_cpm_pcie_probe,
611 builtin_platform_driver(xilinx_cpm_pcie_driver);