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
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 /* Only one device down on each root port */
33 if (pci_is_root_bus(bus) && (devfn > 0))
37 * Do not read more than one device on the bus directly
40 if ((bus->primary == to_pci_host_bridge(bus->bridge)->busnr) && (PCI_SLOT(devfn) > 0))
47 * mobiveil_pcie_map_bus - routine to get the configuration base of either
48 * root port or endpoint
50 static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
51 unsigned int devfn, int where)
53 struct mobiveil_pcie *pcie = bus->sysdata;
54 struct mobiveil_root_port *rp = &pcie->rp;
57 if (!mobiveil_pcie_valid_device(bus, devfn))
60 /* RC config access */
61 if (pci_is_root_bus(bus))
62 return pcie->csr_axi_slave_base + where;
65 * EP config access (in Config/APIO space)
66 * Program PEX Address base (31..16 bits) with appropriate value
67 * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
68 * Relies on pci_lock serialization
70 value = bus->number << PAB_BUS_SHIFT |
71 PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
72 PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT;
74 mobiveil_csr_writel(pcie, value, PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
76 return rp->config_axi_slave_base + where;
79 static struct pci_ops mobiveil_pcie_ops = {
80 .map_bus = mobiveil_pcie_map_bus,
81 .read = pci_generic_config_read,
82 .write = pci_generic_config_write,
85 static void mobiveil_pcie_isr(struct irq_desc *desc)
87 struct irq_chip *chip = irq_desc_get_chip(desc);
88 struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
89 struct device *dev = &pcie->pdev->dev;
90 struct mobiveil_root_port *rp = &pcie->rp;
91 struct mobiveil_msi *msi = &rp->msi;
92 u32 msi_data, msi_addr_lo, msi_addr_hi;
93 u32 intr_status, msi_status;
94 unsigned long shifted_status;
98 * The core provides a single interrupt for both INTx/MSI messages.
99 * So we'll read both INTx and MSI status
102 chained_irq_enter(chip, desc);
104 /* read INTx status */
105 val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
106 mask = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
107 intr_status = val & mask;
110 if (intr_status & PAB_INTP_INTX_MASK) {
111 shifted_status = mobiveil_csr_readl(pcie,
112 PAB_INTP_AMBA_MISC_STAT);
113 shifted_status &= PAB_INTP_INTX_MASK;
114 shifted_status >>= PAB_INTX_START;
116 for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
118 ret = generic_handle_domain_irq(rp->intx_domain,
121 dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
124 /* clear interrupt handled */
125 mobiveil_csr_writel(pcie,
126 1 << (PAB_INTX_START + bit),
127 PAB_INTP_AMBA_MISC_STAT);
130 shifted_status = mobiveil_csr_readl(pcie,
131 PAB_INTP_AMBA_MISC_STAT);
132 shifted_status &= PAB_INTP_INTX_MASK;
133 shifted_status >>= PAB_INTX_START;
134 } while (shifted_status != 0);
137 /* read extra MSI status register */
138 msi_status = readl_relaxed(pcie->apb_csr_base + MSI_STATUS_OFFSET);
140 /* handle MSI interrupts */
141 while (msi_status & 1) {
142 msi_data = readl_relaxed(pcie->apb_csr_base + MSI_DATA_OFFSET);
145 * MSI_STATUS_OFFSET register gets updated to zero
146 * once we pop not only the MSI data but also address
147 * from MSI hardware FIFO. So keeping these following
150 msi_addr_lo = readl_relaxed(pcie->apb_csr_base +
152 msi_addr_hi = readl_relaxed(pcie->apb_csr_base +
154 dev_dbg(dev, "MSI registers, data: %08x, addr: %08x:%08x\n",
155 msi_data, msi_addr_hi, msi_addr_lo);
157 generic_handle_domain_irq(msi->dev_domain, msi_data);
159 msi_status = readl_relaxed(pcie->apb_csr_base +
163 /* Clear the interrupt status */
164 mobiveil_csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
165 chained_irq_exit(chip, desc);
168 static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
170 struct device *dev = &pcie->pdev->dev;
171 struct platform_device *pdev = pcie->pdev;
172 struct device_node *node = dev->of_node;
173 struct mobiveil_root_port *rp = &pcie->rp;
174 struct resource *res;
176 /* map config resource */
177 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
179 rp->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
180 if (IS_ERR(rp->config_axi_slave_base))
181 return PTR_ERR(rp->config_axi_slave_base);
184 /* map csr resource */
185 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
187 pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
188 if (IS_ERR(pcie->csr_axi_slave_base))
189 return PTR_ERR(pcie->csr_axi_slave_base);
190 pcie->pcie_reg_base = res->start;
192 /* read the number of windows requested */
193 if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
194 pcie->apio_wins = MAX_PIO_WINDOWS;
196 if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
197 pcie->ppio_wins = MAX_PIO_WINDOWS;
202 static void mobiveil_pcie_enable_msi(struct mobiveil_pcie *pcie)
204 phys_addr_t msg_addr = pcie->pcie_reg_base;
205 struct mobiveil_msi *msi = &pcie->rp.msi;
207 msi->num_of_vectors = PCI_NUM_MSI;
208 msi->msi_pages_phys = (phys_addr_t)msg_addr;
210 writel_relaxed(lower_32_bits(msg_addr),
211 pcie->apb_csr_base + MSI_BASE_LO_OFFSET);
212 writel_relaxed(upper_32_bits(msg_addr),
213 pcie->apb_csr_base + MSI_BASE_HI_OFFSET);
214 writel_relaxed(4096, pcie->apb_csr_base + MSI_SIZE_OFFSET);
215 writel_relaxed(1, pcie->apb_csr_base + MSI_ENABLE_OFFSET);
218 int mobiveil_host_init(struct mobiveil_pcie *pcie, bool reinit)
220 struct mobiveil_root_port *rp = &pcie->rp;
221 struct pci_host_bridge *bridge = rp->bridge;
222 u32 value, pab_ctrl, type;
223 struct resource_entry *win;
225 pcie->ib_wins_configured = 0;
226 pcie->ob_wins_configured = 0;
229 /* setup bus numbers */
230 value = mobiveil_csr_readl(pcie, PCI_PRIMARY_BUS);
233 mobiveil_csr_writel(pcie, value, PCI_PRIMARY_BUS);
237 * program Bus Master Enable Bit in Command Register in PAB Config
240 value = mobiveil_csr_readl(pcie, PCI_COMMAND);
241 value |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
242 mobiveil_csr_writel(pcie, value, PCI_COMMAND);
245 * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
248 pab_ctrl = mobiveil_csr_readl(pcie, PAB_CTRL);
249 pab_ctrl |= (1 << AMBA_PIO_ENABLE_SHIFT) | (1 << PEX_PIO_ENABLE_SHIFT);
250 mobiveil_csr_writel(pcie, pab_ctrl, PAB_CTRL);
253 * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
254 * PAB_AXI_PIO_CTRL Register
256 value = mobiveil_csr_readl(pcie, PAB_AXI_PIO_CTRL);
257 value |= APIO_EN_MASK;
258 mobiveil_csr_writel(pcie, value, PAB_AXI_PIO_CTRL);
260 /* Enable PCIe PIO master */
261 value = mobiveil_csr_readl(pcie, PAB_PEX_PIO_CTRL);
262 value |= 1 << PIO_ENABLE_SHIFT;
263 mobiveil_csr_writel(pcie, value, PAB_PEX_PIO_CTRL);
266 * we'll program one outbound window for config reads and
267 * another default inbound window for all the upstream traffic
268 * rest of the outbound windows will be configured according to
269 * the "ranges" field defined in device tree
272 /* config outbound translation window */
273 program_ob_windows(pcie, WIN_NUM_0, rp->ob_io_res->start, 0,
274 CFG_WINDOW_TYPE, resource_size(rp->ob_io_res));
276 /* memory inbound translation window */
277 program_ib_windows(pcie, WIN_NUM_0, 0, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
279 /* Get the I/O and memory ranges from DT */
280 resource_list_for_each_entry(win, &bridge->windows) {
281 if (resource_type(win->res) == IORESOURCE_MEM)
282 type = MEM_WINDOW_TYPE;
283 else if (resource_type(win->res) == IORESOURCE_IO)
284 type = IO_WINDOW_TYPE;
288 /* configure outbound translation window */
289 program_ob_windows(pcie, pcie->ob_wins_configured,
291 win->res->start - win->offset,
292 type, resource_size(win->res));
295 /* fixup for PCIe class register */
296 value = mobiveil_csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS);
298 value |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
299 mobiveil_csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS);
304 static void mobiveil_mask_intx_irq(struct irq_data *data)
306 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
307 struct mobiveil_root_port *rp;
309 u32 mask, shifted_val;
312 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
313 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
314 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
315 shifted_val &= ~mask;
316 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
317 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
320 static void mobiveil_unmask_intx_irq(struct irq_data *data)
322 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
323 struct mobiveil_root_port *rp;
325 u32 shifted_val, mask;
328 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
329 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
330 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
332 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
333 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
336 static struct irq_chip intx_irq_chip = {
337 .name = "mobiveil_pcie:intx",
338 .irq_enable = mobiveil_unmask_intx_irq,
339 .irq_disable = mobiveil_mask_intx_irq,
340 .irq_mask = mobiveil_mask_intx_irq,
341 .irq_unmask = mobiveil_unmask_intx_irq,
344 /* routine to setup the INTx related data */
345 static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
346 irq_hw_number_t hwirq)
348 irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_irq);
349 irq_set_chip_data(irq, domain->host_data);
354 /* INTx domain operations structure */
355 static const struct irq_domain_ops intx_domain_ops = {
356 .map = mobiveil_pcie_intx_map,
359 static struct irq_chip mobiveil_msi_irq_chip = {
360 .name = "Mobiveil PCIe MSI",
361 .irq_mask = pci_msi_mask_irq,
362 .irq_unmask = pci_msi_unmask_irq,
365 static struct msi_domain_info mobiveil_msi_domain_info = {
366 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
368 .chip = &mobiveil_msi_irq_chip,
371 static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
373 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
374 phys_addr_t addr = pcie->pcie_reg_base + (data->hwirq * sizeof(int));
376 msg->address_lo = lower_32_bits(addr);
377 msg->address_hi = upper_32_bits(addr);
378 msg->data = data->hwirq;
380 dev_dbg(&pcie->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n",
381 (int)data->hwirq, msg->address_hi, msg->address_lo);
384 static int mobiveil_msi_set_affinity(struct irq_data *irq_data,
385 const struct cpumask *mask, bool force)
390 static struct irq_chip mobiveil_msi_bottom_irq_chip = {
391 .name = "Mobiveil MSI",
392 .irq_compose_msi_msg = mobiveil_compose_msi_msg,
393 .irq_set_affinity = mobiveil_msi_set_affinity,
396 static int mobiveil_irq_msi_domain_alloc(struct irq_domain *domain,
398 unsigned int nr_irqs, void *args)
400 struct mobiveil_pcie *pcie = domain->host_data;
401 struct mobiveil_msi *msi = &pcie->rp.msi;
404 WARN_ON(nr_irqs != 1);
405 mutex_lock(&msi->lock);
407 bit = find_first_zero_bit(msi->msi_irq_in_use, msi->num_of_vectors);
408 if (bit >= msi->num_of_vectors) {
409 mutex_unlock(&msi->lock);
413 set_bit(bit, msi->msi_irq_in_use);
415 mutex_unlock(&msi->lock);
417 irq_domain_set_info(domain, virq, bit, &mobiveil_msi_bottom_irq_chip,
418 domain->host_data, handle_level_irq, NULL, NULL);
422 static void mobiveil_irq_msi_domain_free(struct irq_domain *domain,
424 unsigned int nr_irqs)
426 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
427 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(d);
428 struct mobiveil_msi *msi = &pcie->rp.msi;
430 mutex_lock(&msi->lock);
432 if (!test_bit(d->hwirq, msi->msi_irq_in_use))
433 dev_err(&pcie->pdev->dev, "trying to free unused MSI#%lu\n",
436 __clear_bit(d->hwirq, msi->msi_irq_in_use);
438 mutex_unlock(&msi->lock);
440 static const struct irq_domain_ops msi_domain_ops = {
441 .alloc = mobiveil_irq_msi_domain_alloc,
442 .free = mobiveil_irq_msi_domain_free,
445 static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
447 struct device *dev = &pcie->pdev->dev;
448 struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
449 struct mobiveil_msi *msi = &pcie->rp.msi;
451 mutex_init(&msi->lock);
452 msi->dev_domain = irq_domain_add_linear(NULL, msi->num_of_vectors,
453 &msi_domain_ops, pcie);
454 if (!msi->dev_domain) {
455 dev_err(dev, "failed to create IRQ domain\n");
459 msi->msi_domain = pci_msi_create_irq_domain(fwnode,
460 &mobiveil_msi_domain_info,
462 if (!msi->msi_domain) {
463 dev_err(dev, "failed to create MSI domain\n");
464 irq_domain_remove(msi->dev_domain);
471 static int mobiveil_pcie_init_irq_domain(struct mobiveil_pcie *pcie)
473 struct device *dev = &pcie->pdev->dev;
474 struct device_node *node = dev->of_node;
475 struct mobiveil_root_port *rp = &pcie->rp;
478 rp->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
479 &intx_domain_ops, pcie);
481 if (!rp->intx_domain) {
482 dev_err(dev, "Failed to get a INTx IRQ domain\n");
486 raw_spin_lock_init(&rp->intx_mask_lock);
489 return mobiveil_allocate_msi_domains(pcie);
492 static int mobiveil_pcie_integrated_interrupt_init(struct mobiveil_pcie *pcie)
494 struct platform_device *pdev = pcie->pdev;
495 struct device *dev = &pdev->dev;
496 struct mobiveil_root_port *rp = &pcie->rp;
497 struct resource *res;
500 /* map MSI config resource */
501 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb_csr");
502 pcie->apb_csr_base = devm_pci_remap_cfg_resource(dev, res);
503 if (IS_ERR(pcie->apb_csr_base))
504 return PTR_ERR(pcie->apb_csr_base);
506 /* setup MSI hardware registers */
507 mobiveil_pcie_enable_msi(pcie);
509 rp->irq = platform_get_irq(pdev, 0);
513 /* initialize the IRQ domains */
514 ret = mobiveil_pcie_init_irq_domain(pcie);
516 dev_err(dev, "Failed creating IRQ Domain\n");
520 irq_set_chained_handler_and_data(rp->irq, mobiveil_pcie_isr, pcie);
522 /* Enable interrupts */
523 mobiveil_csr_writel(pcie, (PAB_INTP_INTX_MASK | PAB_INTP_MSI_MASK),
524 PAB_INTP_AMBA_MISC_ENB);
530 static int mobiveil_pcie_interrupt_init(struct mobiveil_pcie *pcie)
532 struct mobiveil_root_port *rp = &pcie->rp;
534 if (rp->ops->interrupt_init)
535 return rp->ops->interrupt_init(pcie);
537 return mobiveil_pcie_integrated_interrupt_init(pcie);
540 static bool mobiveil_pcie_is_bridge(struct mobiveil_pcie *pcie)
544 header_type = mobiveil_csr_readb(pcie, PCI_HEADER_TYPE);
547 return header_type == PCI_HEADER_TYPE_BRIDGE;
550 int mobiveil_pcie_host_probe(struct mobiveil_pcie *pcie)
552 struct mobiveil_root_port *rp = &pcie->rp;
553 struct pci_host_bridge *bridge = rp->bridge;
554 struct device *dev = &pcie->pdev->dev;
557 ret = mobiveil_pcie_parse_dt(pcie);
559 dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
563 if (!mobiveil_pcie_is_bridge(pcie))
567 * configure all inbound and outbound windows and prepare the RC for
570 ret = mobiveil_host_init(pcie, false);
572 dev_err(dev, "Failed to initialize host\n");
576 ret = mobiveil_pcie_interrupt_init(pcie);
578 dev_err(dev, "Interrupt init failed\n");
582 /* Initialize bridge */
583 bridge->sysdata = pcie;
584 bridge->ops = &mobiveil_pcie_ops;
586 ret = mobiveil_bringup_link(pcie);
588 dev_info(dev, "link bring-up failed\n");
592 return pci_host_probe(bridge);