1 // SPDX-License-Identifier: GPL-2.0
3 * PCIe host controller driver for Mobiveil PCIe Host controller
5 * Copyright (c) 2018 Mobiveil Inc.
6 * Copyright 2019-2020 NXP
8 * Author: Subrahmanya Lingappa <l.subrahmanya@mobiveil.co.in>
9 * Hou Zhiqiang <Zhiqiang.Hou@nxp.com>
12 #include <linux/init.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/irqchip/chained_irq.h>
16 #include <linux/irqdomain.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/msi.h>
20 #include <linux/of_address.h>
21 #include <linux/of_irq.h>
22 #include <linux/of_platform.h>
23 #include <linux/of_pci.h>
24 #include <linux/pci.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
28 #include "pcie-mobiveil.h"
30 static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
32 struct mobiveil_pcie *pcie = bus->sysdata;
33 struct mobiveil_root_port *rp = &pcie->rp;
35 /* Only one device down on each root port */
36 if ((bus->number == rp->root_bus_nr) && (devfn > 0))
40 * Do not read more than one device on the bus directly
43 if ((bus->primary == rp->root_bus_nr) && (PCI_SLOT(devfn) > 0))
50 * mobiveil_pcie_map_bus - routine to get the configuration base of either
51 * root port or endpoint
53 static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
54 unsigned int devfn, int where)
56 struct mobiveil_pcie *pcie = bus->sysdata;
57 struct mobiveil_root_port *rp = &pcie->rp;
60 if (!mobiveil_pcie_valid_device(bus, devfn))
63 /* RC config access */
64 if (bus->number == rp->root_bus_nr)
65 return pcie->csr_axi_slave_base + where;
68 * EP config access (in Config/APIO space)
69 * Program PEX Address base (31..16 bits) with appropriate value
70 * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
71 * Relies on pci_lock serialization
73 value = bus->number << PAB_BUS_SHIFT |
74 PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
75 PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT;
77 mobiveil_csr_writel(pcie, value, PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
79 return rp->config_axi_slave_base + where;
82 static struct pci_ops mobiveil_pcie_ops = {
83 .map_bus = mobiveil_pcie_map_bus,
84 .read = pci_generic_config_read,
85 .write = pci_generic_config_write,
88 static void mobiveil_pcie_isr(struct irq_desc *desc)
90 struct irq_chip *chip = irq_desc_get_chip(desc);
91 struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
92 struct device *dev = &pcie->pdev->dev;
93 struct mobiveil_root_port *rp = &pcie->rp;
94 struct mobiveil_msi *msi = &rp->msi;
95 u32 msi_data, msi_addr_lo, msi_addr_hi;
96 u32 intr_status, msi_status;
97 unsigned long shifted_status;
98 u32 bit, virq, val, mask;
101 * The core provides a single interrupt for both INTx/MSI messages.
102 * So we'll read both INTx and MSI status
105 chained_irq_enter(chip, desc);
107 /* read INTx status */
108 val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
109 mask = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
110 intr_status = val & mask;
113 if (intr_status & PAB_INTP_INTX_MASK) {
114 shifted_status = mobiveil_csr_readl(pcie,
115 PAB_INTP_AMBA_MISC_STAT);
116 shifted_status &= PAB_INTP_INTX_MASK;
117 shifted_status >>= PAB_INTX_START;
119 for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
120 virq = irq_find_mapping(rp->intx_domain,
123 generic_handle_irq(virq);
125 dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
128 /* clear interrupt handled */
129 mobiveil_csr_writel(pcie,
130 1 << (PAB_INTX_START + bit),
131 PAB_INTP_AMBA_MISC_STAT);
134 shifted_status = mobiveil_csr_readl(pcie,
135 PAB_INTP_AMBA_MISC_STAT);
136 shifted_status &= PAB_INTP_INTX_MASK;
137 shifted_status >>= PAB_INTX_START;
138 } while (shifted_status != 0);
141 /* read extra MSI status register */
142 msi_status = readl_relaxed(pcie->apb_csr_base + MSI_STATUS_OFFSET);
144 /* handle MSI interrupts */
145 while (msi_status & 1) {
146 msi_data = readl_relaxed(pcie->apb_csr_base + MSI_DATA_OFFSET);
149 * MSI_STATUS_OFFSET register gets updated to zero
150 * once we pop not only the MSI data but also address
151 * from MSI hardware FIFO. So keeping these following
154 msi_addr_lo = readl_relaxed(pcie->apb_csr_base +
156 msi_addr_hi = readl_relaxed(pcie->apb_csr_base +
158 dev_dbg(dev, "MSI registers, data: %08x, addr: %08x:%08x\n",
159 msi_data, msi_addr_hi, msi_addr_lo);
161 virq = irq_find_mapping(msi->dev_domain, msi_data);
163 generic_handle_irq(virq);
165 msi_status = readl_relaxed(pcie->apb_csr_base +
169 /* Clear the interrupt status */
170 mobiveil_csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
171 chained_irq_exit(chip, desc);
174 static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
176 struct device *dev = &pcie->pdev->dev;
177 struct platform_device *pdev = pcie->pdev;
178 struct device_node *node = dev->of_node;
179 struct mobiveil_root_port *rp = &pcie->rp;
180 struct resource *res;
182 /* map config resource */
183 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
185 rp->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
186 if (IS_ERR(rp->config_axi_slave_base))
187 return PTR_ERR(rp->config_axi_slave_base);
190 /* map csr resource */
191 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
193 pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
194 if (IS_ERR(pcie->csr_axi_slave_base))
195 return PTR_ERR(pcie->csr_axi_slave_base);
196 pcie->pcie_reg_base = res->start;
198 /* read the number of windows requested */
199 if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
200 pcie->apio_wins = MAX_PIO_WINDOWS;
202 if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
203 pcie->ppio_wins = MAX_PIO_WINDOWS;
208 static void mobiveil_pcie_enable_msi(struct mobiveil_pcie *pcie)
210 phys_addr_t msg_addr = pcie->pcie_reg_base;
211 struct mobiveil_msi *msi = &pcie->rp.msi;
213 msi->num_of_vectors = PCI_NUM_MSI;
214 msi->msi_pages_phys = (phys_addr_t)msg_addr;
216 writel_relaxed(lower_32_bits(msg_addr),
217 pcie->apb_csr_base + MSI_BASE_LO_OFFSET);
218 writel_relaxed(upper_32_bits(msg_addr),
219 pcie->apb_csr_base + MSI_BASE_HI_OFFSET);
220 writel_relaxed(4096, pcie->apb_csr_base + MSI_SIZE_OFFSET);
221 writel_relaxed(1, pcie->apb_csr_base + MSI_ENABLE_OFFSET);
224 int mobiveil_host_init(struct mobiveil_pcie *pcie, bool reinit)
226 struct mobiveil_root_port *rp = &pcie->rp;
227 struct pci_host_bridge *bridge = rp->bridge;
228 u32 value, pab_ctrl, type;
229 struct resource_entry *win;
231 pcie->ib_wins_configured = 0;
232 pcie->ob_wins_configured = 0;
235 /* setup bus numbers */
236 value = mobiveil_csr_readl(pcie, PCI_PRIMARY_BUS);
239 mobiveil_csr_writel(pcie, value, PCI_PRIMARY_BUS);
243 * program Bus Master Enable Bit in Command Register in PAB Config
246 value = mobiveil_csr_readl(pcie, PCI_COMMAND);
247 value |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
248 mobiveil_csr_writel(pcie, value, PCI_COMMAND);
251 * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
254 pab_ctrl = mobiveil_csr_readl(pcie, PAB_CTRL);
255 pab_ctrl |= (1 << AMBA_PIO_ENABLE_SHIFT) | (1 << PEX_PIO_ENABLE_SHIFT);
256 mobiveil_csr_writel(pcie, pab_ctrl, PAB_CTRL);
259 * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
260 * PAB_AXI_PIO_CTRL Register
262 value = mobiveil_csr_readl(pcie, PAB_AXI_PIO_CTRL);
263 value |= APIO_EN_MASK;
264 mobiveil_csr_writel(pcie, value, PAB_AXI_PIO_CTRL);
266 /* Enable PCIe PIO master */
267 value = mobiveil_csr_readl(pcie, PAB_PEX_PIO_CTRL);
268 value |= 1 << PIO_ENABLE_SHIFT;
269 mobiveil_csr_writel(pcie, value, PAB_PEX_PIO_CTRL);
272 * we'll program one outbound window for config reads and
273 * another default inbound window for all the upstream traffic
274 * rest of the outbound windows will be configured according to
275 * the "ranges" field defined in device tree
278 /* config outbound translation window */
279 program_ob_windows(pcie, WIN_NUM_0, rp->ob_io_res->start, 0,
280 CFG_WINDOW_TYPE, resource_size(rp->ob_io_res));
282 /* memory inbound translation window */
283 program_ib_windows(pcie, WIN_NUM_0, 0, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
285 /* Get the I/O and memory ranges from DT */
286 resource_list_for_each_entry(win, &bridge->windows) {
287 if (resource_type(win->res) == IORESOURCE_MEM)
288 type = MEM_WINDOW_TYPE;
289 else if (resource_type(win->res) == IORESOURCE_IO)
290 type = IO_WINDOW_TYPE;
294 /* configure outbound translation window */
295 program_ob_windows(pcie, pcie->ob_wins_configured,
297 win->res->start - win->offset,
298 type, resource_size(win->res));
301 /* fixup for PCIe class register */
302 value = mobiveil_csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS);
304 value |= (PCI_CLASS_BRIDGE_PCI << 16);
305 mobiveil_csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS);
310 static void mobiveil_mask_intx_irq(struct irq_data *data)
312 struct irq_desc *desc = irq_to_desc(data->irq);
313 struct mobiveil_pcie *pcie;
314 struct mobiveil_root_port *rp;
316 u32 mask, shifted_val;
318 pcie = irq_desc_get_chip_data(desc);
320 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
321 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
322 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
323 shifted_val &= ~mask;
324 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
325 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
328 static void mobiveil_unmask_intx_irq(struct irq_data *data)
330 struct irq_desc *desc = irq_to_desc(data->irq);
331 struct mobiveil_pcie *pcie;
332 struct mobiveil_root_port *rp;
334 u32 shifted_val, mask;
336 pcie = irq_desc_get_chip_data(desc);
338 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
339 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
340 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
342 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
343 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
346 static struct irq_chip intx_irq_chip = {
347 .name = "mobiveil_pcie:intx",
348 .irq_enable = mobiveil_unmask_intx_irq,
349 .irq_disable = mobiveil_mask_intx_irq,
350 .irq_mask = mobiveil_mask_intx_irq,
351 .irq_unmask = mobiveil_unmask_intx_irq,
354 /* routine to setup the INTx related data */
355 static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
356 irq_hw_number_t hwirq)
358 irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_irq);
359 irq_set_chip_data(irq, domain->host_data);
364 /* INTx domain operations structure */
365 static const struct irq_domain_ops intx_domain_ops = {
366 .map = mobiveil_pcie_intx_map,
369 static struct irq_chip mobiveil_msi_irq_chip = {
370 .name = "Mobiveil PCIe MSI",
371 .irq_mask = pci_msi_mask_irq,
372 .irq_unmask = pci_msi_unmask_irq,
375 static struct msi_domain_info mobiveil_msi_domain_info = {
376 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
378 .chip = &mobiveil_msi_irq_chip,
381 static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
383 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
384 phys_addr_t addr = pcie->pcie_reg_base + (data->hwirq * sizeof(int));
386 msg->address_lo = lower_32_bits(addr);
387 msg->address_hi = upper_32_bits(addr);
388 msg->data = data->hwirq;
390 dev_dbg(&pcie->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n",
391 (int)data->hwirq, msg->address_hi, msg->address_lo);
394 static int mobiveil_msi_set_affinity(struct irq_data *irq_data,
395 const struct cpumask *mask, bool force)
400 static struct irq_chip mobiveil_msi_bottom_irq_chip = {
401 .name = "Mobiveil MSI",
402 .irq_compose_msi_msg = mobiveil_compose_msi_msg,
403 .irq_set_affinity = mobiveil_msi_set_affinity,
406 static int mobiveil_irq_msi_domain_alloc(struct irq_domain *domain,
408 unsigned int nr_irqs, void *args)
410 struct mobiveil_pcie *pcie = domain->host_data;
411 struct mobiveil_msi *msi = &pcie->rp.msi;
414 WARN_ON(nr_irqs != 1);
415 mutex_lock(&msi->lock);
417 bit = find_first_zero_bit(msi->msi_irq_in_use, msi->num_of_vectors);
418 if (bit >= msi->num_of_vectors) {
419 mutex_unlock(&msi->lock);
423 set_bit(bit, msi->msi_irq_in_use);
425 mutex_unlock(&msi->lock);
427 irq_domain_set_info(domain, virq, bit, &mobiveil_msi_bottom_irq_chip,
428 domain->host_data, handle_level_irq, NULL, NULL);
432 static void mobiveil_irq_msi_domain_free(struct irq_domain *domain,
434 unsigned int nr_irqs)
436 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
437 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(d);
438 struct mobiveil_msi *msi = &pcie->rp.msi;
440 mutex_lock(&msi->lock);
442 if (!test_bit(d->hwirq, msi->msi_irq_in_use))
443 dev_err(&pcie->pdev->dev, "trying to free unused MSI#%lu\n",
446 __clear_bit(d->hwirq, msi->msi_irq_in_use);
448 mutex_unlock(&msi->lock);
450 static const struct irq_domain_ops msi_domain_ops = {
451 .alloc = mobiveil_irq_msi_domain_alloc,
452 .free = mobiveil_irq_msi_domain_free,
455 static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
457 struct device *dev = &pcie->pdev->dev;
458 struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
459 struct mobiveil_msi *msi = &pcie->rp.msi;
461 mutex_init(&msi->lock);
462 msi->dev_domain = irq_domain_add_linear(NULL, msi->num_of_vectors,
463 &msi_domain_ops, pcie);
464 if (!msi->dev_domain) {
465 dev_err(dev, "failed to create IRQ domain\n");
469 msi->msi_domain = pci_msi_create_irq_domain(fwnode,
470 &mobiveil_msi_domain_info,
472 if (!msi->msi_domain) {
473 dev_err(dev, "failed to create MSI domain\n");
474 irq_domain_remove(msi->dev_domain);
481 static int mobiveil_pcie_init_irq_domain(struct mobiveil_pcie *pcie)
483 struct device *dev = &pcie->pdev->dev;
484 struct device_node *node = dev->of_node;
485 struct mobiveil_root_port *rp = &pcie->rp;
489 rp->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
490 &intx_domain_ops, pcie);
492 if (!rp->intx_domain) {
493 dev_err(dev, "Failed to get a INTx IRQ domain\n");
497 raw_spin_lock_init(&rp->intx_mask_lock);
500 ret = mobiveil_allocate_msi_domains(pcie);
507 static int mobiveil_pcie_integrated_interrupt_init(struct mobiveil_pcie *pcie)
509 struct platform_device *pdev = pcie->pdev;
510 struct device *dev = &pdev->dev;
511 struct mobiveil_root_port *rp = &pcie->rp;
512 struct resource *res;
515 /* map MSI config resource */
516 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb_csr");
517 pcie->apb_csr_base = devm_pci_remap_cfg_resource(dev, res);
518 if (IS_ERR(pcie->apb_csr_base))
519 return PTR_ERR(pcie->apb_csr_base);
521 /* setup MSI hardware registers */
522 mobiveil_pcie_enable_msi(pcie);
524 rp->irq = platform_get_irq(pdev, 0);
526 dev_err(dev, "failed to map IRQ: %d\n", rp->irq);
530 /* initialize the IRQ domains */
531 ret = mobiveil_pcie_init_irq_domain(pcie);
533 dev_err(dev, "Failed creating IRQ Domain\n");
537 irq_set_chained_handler_and_data(rp->irq, mobiveil_pcie_isr, pcie);
539 /* Enable interrupts */
540 mobiveil_csr_writel(pcie, (PAB_INTP_INTX_MASK | PAB_INTP_MSI_MASK),
541 PAB_INTP_AMBA_MISC_ENB);
547 static int mobiveil_pcie_interrupt_init(struct mobiveil_pcie *pcie)
549 struct mobiveil_root_port *rp = &pcie->rp;
551 if (rp->ops->interrupt_init)
552 return rp->ops->interrupt_init(pcie);
554 return mobiveil_pcie_integrated_interrupt_init(pcie);
557 static bool mobiveil_pcie_is_bridge(struct mobiveil_pcie *pcie)
561 header_type = mobiveil_csr_readb(pcie, PCI_HEADER_TYPE);
564 return header_type == PCI_HEADER_TYPE_BRIDGE;
567 int mobiveil_pcie_host_probe(struct mobiveil_pcie *pcie)
569 struct mobiveil_root_port *rp = &pcie->rp;
570 struct pci_host_bridge *bridge = rp->bridge;
571 struct device *dev = &pcie->pdev->dev;
573 struct pci_bus *child;
576 ret = mobiveil_pcie_parse_dt(pcie);
578 dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
582 if (!mobiveil_pcie_is_bridge(pcie))
585 /* parse the host bridge base addresses from the device tree file */
586 ret = pci_parse_request_of_pci_ranges(dev, &bridge->windows,
587 &bridge->dma_ranges, NULL);
589 dev_err(dev, "Getting bridge resources failed\n");
594 * configure all inbound and outbound windows and prepare the RC for
597 ret = mobiveil_host_init(pcie, false);
599 dev_err(dev, "Failed to initialize host\n");
603 ret = mobiveil_pcie_interrupt_init(pcie);
605 dev_err(dev, "Interrupt init failed\n");
609 /* Initialize bridge */
610 bridge->dev.parent = dev;
611 bridge->sysdata = pcie;
612 bridge->busnr = rp->root_bus_nr;
613 bridge->ops = &mobiveil_pcie_ops;
614 bridge->map_irq = of_irq_parse_and_map_pci;
615 bridge->swizzle_irq = pci_common_swizzle;
617 ret = mobiveil_bringup_link(pcie);
619 dev_info(dev, "link bring-up failed\n");
623 /* setup the kernel resources for the newly added PCIe root bus */
624 ret = pci_scan_root_bus_bridge(bridge);
630 pci_assign_unassigned_bus_resources(bus);
631 list_for_each_entry(child, &bus->children, node)
632 pcie_bus_configure_settings(child);
633 pci_bus_add_devices(bus);