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_pci.h>
21 #include <linux/pci.h>
22 #include <linux/platform_device.h>
23 #include <linux/slab.h>
25 #include "pcie-mobiveil.h"
27 static bool mobiveil_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
29 /* Only one device down on each root port */
30 if (pci_is_root_bus(bus) && (devfn > 0))
34 * Do not read more than one device on the bus directly
37 if ((bus->primary == to_pci_host_bridge(bus->bridge)->busnr) && (PCI_SLOT(devfn) > 0))
44 * mobiveil_pcie_map_bus - routine to get the configuration base of either
45 * root port or endpoint
47 static void __iomem *mobiveil_pcie_map_bus(struct pci_bus *bus,
48 unsigned int devfn, int where)
50 struct mobiveil_pcie *pcie = bus->sysdata;
51 struct mobiveil_root_port *rp = &pcie->rp;
54 if (!mobiveil_pcie_valid_device(bus, devfn))
57 /* RC config access */
58 if (pci_is_root_bus(bus))
59 return pcie->csr_axi_slave_base + where;
62 * EP config access (in Config/APIO space)
63 * Program PEX Address base (31..16 bits) with appropriate value
64 * (BDF) in PAB_AXI_AMAP_PEX_WIN_L0 Register.
65 * Relies on pci_lock serialization
67 value = bus->number << PAB_BUS_SHIFT |
68 PCI_SLOT(devfn) << PAB_DEVICE_SHIFT |
69 PCI_FUNC(devfn) << PAB_FUNCTION_SHIFT;
71 mobiveil_csr_writel(pcie, value, PAB_AXI_AMAP_PEX_WIN_L(WIN_NUM_0));
73 return rp->config_axi_slave_base + where;
76 static struct pci_ops mobiveil_pcie_ops = {
77 .map_bus = mobiveil_pcie_map_bus,
78 .read = pci_generic_config_read,
79 .write = pci_generic_config_write,
82 static void mobiveil_pcie_isr(struct irq_desc *desc)
84 struct irq_chip *chip = irq_desc_get_chip(desc);
85 struct mobiveil_pcie *pcie = irq_desc_get_handler_data(desc);
86 struct device *dev = &pcie->pdev->dev;
87 struct mobiveil_root_port *rp = &pcie->rp;
88 struct mobiveil_msi *msi = &rp->msi;
89 u32 msi_data, msi_addr_lo, msi_addr_hi;
90 u32 intr_status, msi_status;
91 unsigned long shifted_status;
95 * The core provides a single interrupt for both INTx/MSI messages.
96 * So we'll read both INTx and MSI status
99 chained_irq_enter(chip, desc);
101 /* read INTx status */
102 val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_STAT);
103 mask = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
104 intr_status = val & mask;
107 if (intr_status & PAB_INTP_INTX_MASK) {
108 shifted_status = mobiveil_csr_readl(pcie,
109 PAB_INTP_AMBA_MISC_STAT);
110 shifted_status &= PAB_INTP_INTX_MASK;
111 shifted_status >>= PAB_INTX_START;
113 for_each_set_bit(bit, &shifted_status, PCI_NUM_INTX) {
115 ret = generic_handle_domain_irq(rp->intx_domain,
118 dev_err_ratelimited(dev, "unexpected IRQ, INT%d\n",
121 /* clear interrupt handled */
122 mobiveil_csr_writel(pcie,
123 1 << (PAB_INTX_START + bit),
124 PAB_INTP_AMBA_MISC_STAT);
127 shifted_status = mobiveil_csr_readl(pcie,
128 PAB_INTP_AMBA_MISC_STAT);
129 shifted_status &= PAB_INTP_INTX_MASK;
130 shifted_status >>= PAB_INTX_START;
131 } while (shifted_status != 0);
134 /* read extra MSI status register */
135 msi_status = readl_relaxed(pcie->apb_csr_base + MSI_STATUS_OFFSET);
137 /* handle MSI interrupts */
138 while (msi_status & 1) {
139 msi_data = readl_relaxed(pcie->apb_csr_base + MSI_DATA_OFFSET);
142 * MSI_STATUS_OFFSET register gets updated to zero
143 * once we pop not only the MSI data but also address
144 * from MSI hardware FIFO. So keeping these following
147 msi_addr_lo = readl_relaxed(pcie->apb_csr_base +
149 msi_addr_hi = readl_relaxed(pcie->apb_csr_base +
151 dev_dbg(dev, "MSI registers, data: %08x, addr: %08x:%08x\n",
152 msi_data, msi_addr_hi, msi_addr_lo);
154 generic_handle_domain_irq(msi->dev_domain, msi_data);
156 msi_status = readl_relaxed(pcie->apb_csr_base +
160 /* Clear the interrupt status */
161 mobiveil_csr_writel(pcie, intr_status, PAB_INTP_AMBA_MISC_STAT);
162 chained_irq_exit(chip, desc);
165 static int mobiveil_pcie_parse_dt(struct mobiveil_pcie *pcie)
167 struct device *dev = &pcie->pdev->dev;
168 struct platform_device *pdev = pcie->pdev;
169 struct device_node *node = dev->of_node;
170 struct mobiveil_root_port *rp = &pcie->rp;
171 struct resource *res;
173 /* map config resource */
174 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
176 rp->config_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
177 if (IS_ERR(rp->config_axi_slave_base))
178 return PTR_ERR(rp->config_axi_slave_base);
181 /* map csr resource */
182 res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
184 pcie->csr_axi_slave_base = devm_pci_remap_cfg_resource(dev, res);
185 if (IS_ERR(pcie->csr_axi_slave_base))
186 return PTR_ERR(pcie->csr_axi_slave_base);
187 pcie->pcie_reg_base = res->start;
189 /* read the number of windows requested */
190 if (of_property_read_u32(node, "apio-wins", &pcie->apio_wins))
191 pcie->apio_wins = MAX_PIO_WINDOWS;
193 if (of_property_read_u32(node, "ppio-wins", &pcie->ppio_wins))
194 pcie->ppio_wins = MAX_PIO_WINDOWS;
199 static void mobiveil_pcie_enable_msi(struct mobiveil_pcie *pcie)
201 phys_addr_t msg_addr = pcie->pcie_reg_base;
202 struct mobiveil_msi *msi = &pcie->rp.msi;
204 msi->num_of_vectors = PCI_NUM_MSI;
205 msi->msi_pages_phys = (phys_addr_t)msg_addr;
207 writel_relaxed(lower_32_bits(msg_addr),
208 pcie->apb_csr_base + MSI_BASE_LO_OFFSET);
209 writel_relaxed(upper_32_bits(msg_addr),
210 pcie->apb_csr_base + MSI_BASE_HI_OFFSET);
211 writel_relaxed(4096, pcie->apb_csr_base + MSI_SIZE_OFFSET);
212 writel_relaxed(1, pcie->apb_csr_base + MSI_ENABLE_OFFSET);
215 int mobiveil_host_init(struct mobiveil_pcie *pcie, bool reinit)
217 struct mobiveil_root_port *rp = &pcie->rp;
218 struct pci_host_bridge *bridge = rp->bridge;
219 u32 value, pab_ctrl, type;
220 struct resource_entry *win;
222 pcie->ib_wins_configured = 0;
223 pcie->ob_wins_configured = 0;
226 /* setup bus numbers */
227 value = mobiveil_csr_readl(pcie, PCI_PRIMARY_BUS);
230 mobiveil_csr_writel(pcie, value, PCI_PRIMARY_BUS);
234 * program Bus Master Enable Bit in Command Register in PAB Config
237 value = mobiveil_csr_readl(pcie, PCI_COMMAND);
238 value |= PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER;
239 mobiveil_csr_writel(pcie, value, PCI_COMMAND);
242 * program PIO Enable Bit to 1 (and PEX PIO Enable to 1) in PAB_CTRL
245 pab_ctrl = mobiveil_csr_readl(pcie, PAB_CTRL);
246 pab_ctrl |= (1 << AMBA_PIO_ENABLE_SHIFT) | (1 << PEX_PIO_ENABLE_SHIFT);
247 mobiveil_csr_writel(pcie, pab_ctrl, PAB_CTRL);
250 * program PIO Enable Bit to 1 and Config Window Enable Bit to 1 in
251 * PAB_AXI_PIO_CTRL Register
253 value = mobiveil_csr_readl(pcie, PAB_AXI_PIO_CTRL);
254 value |= APIO_EN_MASK;
255 mobiveil_csr_writel(pcie, value, PAB_AXI_PIO_CTRL);
257 /* Enable PCIe PIO master */
258 value = mobiveil_csr_readl(pcie, PAB_PEX_PIO_CTRL);
259 value |= 1 << PIO_ENABLE_SHIFT;
260 mobiveil_csr_writel(pcie, value, PAB_PEX_PIO_CTRL);
263 * we'll program one outbound window for config reads and
264 * another default inbound window for all the upstream traffic
265 * rest of the outbound windows will be configured according to
266 * the "ranges" field defined in device tree
269 /* config outbound translation window */
270 program_ob_windows(pcie, WIN_NUM_0, rp->ob_io_res->start, 0,
271 CFG_WINDOW_TYPE, resource_size(rp->ob_io_res));
273 /* memory inbound translation window */
274 program_ib_windows(pcie, WIN_NUM_0, 0, 0, MEM_WINDOW_TYPE, IB_WIN_SIZE);
276 /* Get the I/O and memory ranges from DT */
277 resource_list_for_each_entry(win, &bridge->windows) {
278 if (resource_type(win->res) == IORESOURCE_MEM)
279 type = MEM_WINDOW_TYPE;
280 else if (resource_type(win->res) == IORESOURCE_IO)
281 type = IO_WINDOW_TYPE;
285 /* configure outbound translation window */
286 program_ob_windows(pcie, pcie->ob_wins_configured,
288 win->res->start - win->offset,
289 type, resource_size(win->res));
292 /* fixup for PCIe class register */
293 value = mobiveil_csr_readl(pcie, PAB_INTP_AXI_PIO_CLASS);
295 value |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
296 mobiveil_csr_writel(pcie, value, PAB_INTP_AXI_PIO_CLASS);
301 static void mobiveil_mask_intx_irq(struct irq_data *data)
303 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
304 struct mobiveil_root_port *rp;
306 u32 mask, shifted_val;
309 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
310 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
311 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
312 shifted_val &= ~mask;
313 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
314 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
317 static void mobiveil_unmask_intx_irq(struct irq_data *data)
319 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
320 struct mobiveil_root_port *rp;
322 u32 shifted_val, mask;
325 mask = 1 << ((data->hwirq + PAB_INTX_START) - 1);
326 raw_spin_lock_irqsave(&rp->intx_mask_lock, flags);
327 shifted_val = mobiveil_csr_readl(pcie, PAB_INTP_AMBA_MISC_ENB);
329 mobiveil_csr_writel(pcie, shifted_val, PAB_INTP_AMBA_MISC_ENB);
330 raw_spin_unlock_irqrestore(&rp->intx_mask_lock, flags);
333 static struct irq_chip intx_irq_chip = {
334 .name = "mobiveil_pcie:intx",
335 .irq_enable = mobiveil_unmask_intx_irq,
336 .irq_disable = mobiveil_mask_intx_irq,
337 .irq_mask = mobiveil_mask_intx_irq,
338 .irq_unmask = mobiveil_unmask_intx_irq,
341 /* routine to setup the INTx related data */
342 static int mobiveil_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
343 irq_hw_number_t hwirq)
345 irq_set_chip_and_handler(irq, &intx_irq_chip, handle_level_irq);
346 irq_set_chip_data(irq, domain->host_data);
351 /* INTx domain operations structure */
352 static const struct irq_domain_ops intx_domain_ops = {
353 .map = mobiveil_pcie_intx_map,
356 static struct irq_chip mobiveil_msi_irq_chip = {
357 .name = "Mobiveil PCIe MSI",
358 .irq_mask = pci_msi_mask_irq,
359 .irq_unmask = pci_msi_unmask_irq,
362 static struct msi_domain_info mobiveil_msi_domain_info = {
363 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
364 MSI_FLAG_NO_AFFINITY | MSI_FLAG_PCI_MSIX,
365 .chip = &mobiveil_msi_irq_chip,
368 static void mobiveil_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
370 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(data);
371 phys_addr_t addr = pcie->pcie_reg_base + (data->hwirq * sizeof(int));
373 msg->address_lo = lower_32_bits(addr);
374 msg->address_hi = upper_32_bits(addr);
375 msg->data = data->hwirq;
377 dev_dbg(&pcie->pdev->dev, "msi#%d address_hi %#x address_lo %#x\n",
378 (int)data->hwirq, msg->address_hi, msg->address_lo);
381 static struct irq_chip mobiveil_msi_bottom_irq_chip = {
382 .name = "Mobiveil MSI",
383 .irq_compose_msi_msg = mobiveil_compose_msi_msg,
386 static int mobiveil_irq_msi_domain_alloc(struct irq_domain *domain,
388 unsigned int nr_irqs, void *args)
390 struct mobiveil_pcie *pcie = domain->host_data;
391 struct mobiveil_msi *msi = &pcie->rp.msi;
394 WARN_ON(nr_irqs != 1);
395 mutex_lock(&msi->lock);
397 bit = find_first_zero_bit(msi->msi_irq_in_use, msi->num_of_vectors);
398 if (bit >= msi->num_of_vectors) {
399 mutex_unlock(&msi->lock);
403 set_bit(bit, msi->msi_irq_in_use);
405 mutex_unlock(&msi->lock);
407 irq_domain_set_info(domain, virq, bit, &mobiveil_msi_bottom_irq_chip,
408 domain->host_data, handle_level_irq, NULL, NULL);
412 static void mobiveil_irq_msi_domain_free(struct irq_domain *domain,
414 unsigned int nr_irqs)
416 struct irq_data *d = irq_domain_get_irq_data(domain, virq);
417 struct mobiveil_pcie *pcie = irq_data_get_irq_chip_data(d);
418 struct mobiveil_msi *msi = &pcie->rp.msi;
420 mutex_lock(&msi->lock);
422 if (!test_bit(d->hwirq, msi->msi_irq_in_use))
423 dev_err(&pcie->pdev->dev, "trying to free unused MSI#%lu\n",
426 __clear_bit(d->hwirq, msi->msi_irq_in_use);
428 mutex_unlock(&msi->lock);
430 static const struct irq_domain_ops msi_domain_ops = {
431 .alloc = mobiveil_irq_msi_domain_alloc,
432 .free = mobiveil_irq_msi_domain_free,
435 static int mobiveil_allocate_msi_domains(struct mobiveil_pcie *pcie)
437 struct device *dev = &pcie->pdev->dev;
438 struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
439 struct mobiveil_msi *msi = &pcie->rp.msi;
441 mutex_init(&msi->lock);
442 msi->dev_domain = irq_domain_add_linear(NULL, msi->num_of_vectors,
443 &msi_domain_ops, pcie);
444 if (!msi->dev_domain) {
445 dev_err(dev, "failed to create IRQ domain\n");
449 msi->msi_domain = pci_msi_create_irq_domain(fwnode,
450 &mobiveil_msi_domain_info,
452 if (!msi->msi_domain) {
453 dev_err(dev, "failed to create MSI domain\n");
454 irq_domain_remove(msi->dev_domain);
461 static int mobiveil_pcie_init_irq_domain(struct mobiveil_pcie *pcie)
463 struct device *dev = &pcie->pdev->dev;
464 struct device_node *node = dev->of_node;
465 struct mobiveil_root_port *rp = &pcie->rp;
468 rp->intx_domain = irq_domain_add_linear(node, PCI_NUM_INTX,
469 &intx_domain_ops, pcie);
471 if (!rp->intx_domain) {
472 dev_err(dev, "Failed to get a INTx IRQ domain\n");
476 raw_spin_lock_init(&rp->intx_mask_lock);
479 return mobiveil_allocate_msi_domains(pcie);
482 static int mobiveil_pcie_integrated_interrupt_init(struct mobiveil_pcie *pcie)
484 struct platform_device *pdev = pcie->pdev;
485 struct device *dev = &pdev->dev;
486 struct mobiveil_root_port *rp = &pcie->rp;
487 struct resource *res;
490 /* map MSI config resource */
491 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "apb_csr");
492 pcie->apb_csr_base = devm_pci_remap_cfg_resource(dev, res);
493 if (IS_ERR(pcie->apb_csr_base))
494 return PTR_ERR(pcie->apb_csr_base);
496 /* setup MSI hardware registers */
497 mobiveil_pcie_enable_msi(pcie);
499 rp->irq = platform_get_irq(pdev, 0);
503 /* initialize the IRQ domains */
504 ret = mobiveil_pcie_init_irq_domain(pcie);
506 dev_err(dev, "Failed creating IRQ Domain\n");
510 irq_set_chained_handler_and_data(rp->irq, mobiveil_pcie_isr, pcie);
512 /* Enable interrupts */
513 mobiveil_csr_writel(pcie, (PAB_INTP_INTX_MASK | PAB_INTP_MSI_MASK),
514 PAB_INTP_AMBA_MISC_ENB);
520 static int mobiveil_pcie_interrupt_init(struct mobiveil_pcie *pcie)
522 struct mobiveil_root_port *rp = &pcie->rp;
524 if (rp->ops->interrupt_init)
525 return rp->ops->interrupt_init(pcie);
527 return mobiveil_pcie_integrated_interrupt_init(pcie);
530 static bool mobiveil_pcie_is_bridge(struct mobiveil_pcie *pcie)
534 header_type = mobiveil_csr_readb(pcie, PCI_HEADER_TYPE);
535 header_type &= PCI_HEADER_TYPE_MASK;
537 return header_type == PCI_HEADER_TYPE_BRIDGE;
540 int mobiveil_pcie_host_probe(struct mobiveil_pcie *pcie)
542 struct mobiveil_root_port *rp = &pcie->rp;
543 struct pci_host_bridge *bridge = rp->bridge;
544 struct device *dev = &pcie->pdev->dev;
547 ret = mobiveil_pcie_parse_dt(pcie);
549 dev_err(dev, "Parsing DT failed, ret: %x\n", ret);
553 if (!mobiveil_pcie_is_bridge(pcie))
557 * configure all inbound and outbound windows and prepare the RC for
560 ret = mobiveil_host_init(pcie, false);
562 dev_err(dev, "Failed to initialize host\n");
566 ret = mobiveil_pcie_interrupt_init(pcie);
568 dev_err(dev, "Interrupt init failed\n");
572 /* Initialize bridge */
573 bridge->sysdata = pcie;
574 bridge->ops = &mobiveil_pcie_ops;
576 ret = mobiveil_bringup_link(pcie);
578 dev_info(dev, "link bring-up failed\n");
582 return pci_host_probe(bridge);