WIP FPC-III support
[linux/fpc-iii.git] / drivers / pci / controller / pci-xgene.c
blob85e7c98265e81f9e57e3daa6a42d9c330f54fce4
1 // SPDX-License-Identifier: GPL-2.0+
2 /**
3 * APM X-Gene PCIe Driver
5 * Copyright (c) 2014 Applied Micro Circuits Corporation.
7 * Author: Tanmay Inamdar <tinamdar@apm.com>.
8 */
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/io.h>
12 #include <linux/jiffies.h>
13 #include <linux/memblock.h>
14 #include <linux/init.h>
15 #include <linux/of.h>
16 #include <linux/of_address.h>
17 #include <linux/of_irq.h>
18 #include <linux/of_pci.h>
19 #include <linux/pci.h>
20 #include <linux/pci-acpi.h>
21 #include <linux/pci-ecam.h>
22 #include <linux/platform_device.h>
23 #include <linux/slab.h>
25 #include "../pci.h"
27 #define PCIECORE_CTLANDSTATUS 0x50
28 #define PIM1_1L 0x80
29 #define IBAR2 0x98
30 #define IR2MSK 0x9c
31 #define PIM2_1L 0xa0
32 #define IBAR3L 0xb4
33 #define IR3MSKL 0xbc
34 #define PIM3_1L 0xc4
35 #define OMR1BARL 0x100
36 #define OMR2BARL 0x118
37 #define OMR3BARL 0x130
38 #define CFGBARL 0x154
39 #define CFGBARH 0x158
40 #define CFGCTL 0x15c
41 #define RTDID 0x160
42 #define BRIDGE_CFG_0 0x2000
43 #define BRIDGE_CFG_4 0x2010
44 #define BRIDGE_STATUS_0 0x2600
46 #define LINK_UP_MASK 0x00000100
47 #define AXI_EP_CFG_ACCESS 0x10000
48 #define EN_COHERENCY 0xF0000000
49 #define EN_REG 0x00000001
50 #define OB_LO_IO 0x00000002
51 #define XGENE_PCIE_VENDORID 0x10E8
52 #define XGENE_PCIE_DEVICEID 0xE004
53 #define SZ_1T (SZ_1G*1024ULL)
54 #define PIPE_PHY_RATE_RD(src) ((0xc000 & (u32)(src)) >> 0xe)
56 #define XGENE_V1_PCI_EXP_CAP 0x40
58 /* PCIe IP version */
59 #define XGENE_PCIE_IP_VER_UNKN 0
60 #define XGENE_PCIE_IP_VER_1 1
61 #define XGENE_PCIE_IP_VER_2 2
63 #if defined(CONFIG_PCI_XGENE) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
64 struct xgene_pcie_port {
65 struct device_node *node;
66 struct device *dev;
67 struct clk *clk;
68 void __iomem *csr_base;
69 void __iomem *cfg_base;
70 unsigned long cfg_addr;
71 bool link_up;
72 u32 version;
75 static u32 xgene_pcie_readl(struct xgene_pcie_port *port, u32 reg)
77 return readl(port->csr_base + reg);
80 static void xgene_pcie_writel(struct xgene_pcie_port *port, u32 reg, u32 val)
82 writel(val, port->csr_base + reg);
85 static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
87 return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags;
90 static inline struct xgene_pcie_port *pcie_bus_to_port(struct pci_bus *bus)
92 struct pci_config_window *cfg;
94 if (acpi_disabled)
95 return (struct xgene_pcie_port *)(bus->sysdata);
97 cfg = bus->sysdata;
98 return (struct xgene_pcie_port *)(cfg->priv);
102 * When the address bit [17:16] is 2'b01, the Configuration access will be
103 * treated as Type 1 and it will be forwarded to external PCIe device.
105 static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
107 struct xgene_pcie_port *port = pcie_bus_to_port(bus);
109 if (bus->number >= (bus->primary + 1))
110 return port->cfg_base + AXI_EP_CFG_ACCESS;
112 return port->cfg_base;
116 * For Configuration request, RTDID register is used as Bus Number,
117 * Device Number and Function number of the header fields.
119 static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
121 struct xgene_pcie_port *port = pcie_bus_to_port(bus);
122 unsigned int b, d, f;
123 u32 rtdid_val = 0;
125 b = bus->number;
126 d = PCI_SLOT(devfn);
127 f = PCI_FUNC(devfn);
129 if (!pci_is_root_bus(bus))
130 rtdid_val = (b << 8) | (d << 3) | f;
132 xgene_pcie_writel(port, RTDID, rtdid_val);
133 /* read the register back to ensure flush */
134 xgene_pcie_readl(port, RTDID);
138 * X-Gene PCIe port uses BAR0-BAR1 of RC's configuration space as
139 * the translation from PCI bus to native BUS. Entire DDR region
140 * is mapped into PCIe space using these registers, so it can be
141 * reached by DMA from EP devices. The BAR0/1 of bridge should be
142 * hidden during enumeration to avoid the sizing and resource allocation
143 * by PCIe core.
145 static bool xgene_pcie_hide_rc_bars(struct pci_bus *bus, int offset)
147 if (pci_is_root_bus(bus) && ((offset == PCI_BASE_ADDRESS_0) ||
148 (offset == PCI_BASE_ADDRESS_1)))
149 return true;
151 return false;
154 static void __iomem *xgene_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
155 int offset)
157 if ((pci_is_root_bus(bus) && devfn != 0) ||
158 xgene_pcie_hide_rc_bars(bus, offset))
159 return NULL;
161 xgene_pcie_set_rtdid_reg(bus, devfn);
162 return xgene_pcie_get_cfg_base(bus) + offset;
165 static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
166 int where, int size, u32 *val)
168 struct xgene_pcie_port *port = pcie_bus_to_port(bus);
170 if (pci_generic_config_read32(bus, devfn, where & ~0x3, 4, val) !=
171 PCIBIOS_SUCCESSFUL)
172 return PCIBIOS_DEVICE_NOT_FOUND;
175 * The v1 controller has a bug in its Configuration Request
176 * Retry Status (CRS) logic: when CRS is enabled and we read the
177 * Vendor and Device ID of a non-existent device, the controller
178 * fabricates return data of 0xFFFF0001 ("device exists but is not
179 * ready") instead of 0xFFFFFFFF ("device does not exist"). This
180 * causes the PCI core to retry the read until it times out.
181 * Avoid this by not claiming to support CRS.
183 if (pci_is_root_bus(bus) && (port->version == XGENE_PCIE_IP_VER_1) &&
184 ((where & ~0x3) == XGENE_V1_PCI_EXP_CAP + PCI_EXP_RTCTL))
185 *val &= ~(PCI_EXP_RTCAP_CRSVIS << 16);
187 if (size <= 2)
188 *val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1);
190 return PCIBIOS_SUCCESSFUL;
192 #endif
194 #if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
195 static int xgene_get_csr_resource(struct acpi_device *adev,
196 struct resource *res)
198 struct device *dev = &adev->dev;
199 struct resource_entry *entry;
200 struct list_head list;
201 unsigned long flags;
202 int ret;
204 INIT_LIST_HEAD(&list);
205 flags = IORESOURCE_MEM;
206 ret = acpi_dev_get_resources(adev, &list,
207 acpi_dev_filter_resource_type_cb,
208 (void *) flags);
209 if (ret < 0) {
210 dev_err(dev, "failed to parse _CRS method, error code %d\n",
211 ret);
212 return ret;
215 if (ret == 0) {
216 dev_err(dev, "no IO and memory resources present in _CRS\n");
217 return -EINVAL;
220 entry = list_first_entry(&list, struct resource_entry, node);
221 *res = *entry->res;
222 acpi_dev_free_resource_list(&list);
223 return 0;
226 static int xgene_pcie_ecam_init(struct pci_config_window *cfg, u32 ipversion)
228 struct device *dev = cfg->parent;
229 struct acpi_device *adev = to_acpi_device(dev);
230 struct xgene_pcie_port *port;
231 struct resource csr;
232 int ret;
234 port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
235 if (!port)
236 return -ENOMEM;
238 ret = xgene_get_csr_resource(adev, &csr);
239 if (ret) {
240 dev_err(dev, "can't get CSR resource\n");
241 return ret;
243 port->csr_base = devm_pci_remap_cfg_resource(dev, &csr);
244 if (IS_ERR(port->csr_base))
245 return PTR_ERR(port->csr_base);
247 port->cfg_base = cfg->win;
248 port->version = ipversion;
250 cfg->priv = port;
251 return 0;
254 static int xgene_v1_pcie_ecam_init(struct pci_config_window *cfg)
256 return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_1);
259 const struct pci_ecam_ops xgene_v1_pcie_ecam_ops = {
260 .init = xgene_v1_pcie_ecam_init,
261 .pci_ops = {
262 .map_bus = xgene_pcie_map_bus,
263 .read = xgene_pcie_config_read32,
264 .write = pci_generic_config_write,
268 static int xgene_v2_pcie_ecam_init(struct pci_config_window *cfg)
270 return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_2);
273 const struct pci_ecam_ops xgene_v2_pcie_ecam_ops = {
274 .init = xgene_v2_pcie_ecam_init,
275 .pci_ops = {
276 .map_bus = xgene_pcie_map_bus,
277 .read = xgene_pcie_config_read32,
278 .write = pci_generic_config_write,
281 #endif
283 #if defined(CONFIG_PCI_XGENE)
284 static u64 xgene_pcie_set_ib_mask(struct xgene_pcie_port *port, u32 addr,
285 u32 flags, u64 size)
287 u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags;
288 u32 val32 = 0;
289 u32 val;
291 val32 = xgene_pcie_readl(port, addr);
292 val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16);
293 xgene_pcie_writel(port, addr, val);
295 val32 = xgene_pcie_readl(port, addr + 0x04);
296 val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16);
297 xgene_pcie_writel(port, addr + 0x04, val);
299 val32 = xgene_pcie_readl(port, addr + 0x04);
300 val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16);
301 xgene_pcie_writel(port, addr + 0x04, val);
303 val32 = xgene_pcie_readl(port, addr + 0x08);
304 val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16);
305 xgene_pcie_writel(port, addr + 0x08, val);
307 return mask;
310 static void xgene_pcie_linkup(struct xgene_pcie_port *port,
311 u32 *lanes, u32 *speed)
313 u32 val32;
315 port->link_up = false;
316 val32 = xgene_pcie_readl(port, PCIECORE_CTLANDSTATUS);
317 if (val32 & LINK_UP_MASK) {
318 port->link_up = true;
319 *speed = PIPE_PHY_RATE_RD(val32);
320 val32 = xgene_pcie_readl(port, BRIDGE_STATUS_0);
321 *lanes = val32 >> 26;
325 static int xgene_pcie_init_port(struct xgene_pcie_port *port)
327 struct device *dev = port->dev;
328 int rc;
330 port->clk = clk_get(dev, NULL);
331 if (IS_ERR(port->clk)) {
332 dev_err(dev, "clock not available\n");
333 return -ENODEV;
336 rc = clk_prepare_enable(port->clk);
337 if (rc) {
338 dev_err(dev, "clock enable failed\n");
339 return rc;
342 return 0;
345 static int xgene_pcie_map_reg(struct xgene_pcie_port *port,
346 struct platform_device *pdev)
348 struct device *dev = port->dev;
349 struct resource *res;
351 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr");
352 port->csr_base = devm_pci_remap_cfg_resource(dev, res);
353 if (IS_ERR(port->csr_base))
354 return PTR_ERR(port->csr_base);
356 port->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg");
357 if (IS_ERR(port->cfg_base))
358 return PTR_ERR(port->cfg_base);
359 port->cfg_addr = res->start;
361 return 0;
364 static void xgene_pcie_setup_ob_reg(struct xgene_pcie_port *port,
365 struct resource *res, u32 offset,
366 u64 cpu_addr, u64 pci_addr)
368 struct device *dev = port->dev;
369 resource_size_t size = resource_size(res);
370 u64 restype = resource_type(res);
371 u64 mask = 0;
372 u32 min_size;
373 u32 flag = EN_REG;
375 if (restype == IORESOURCE_MEM) {
376 min_size = SZ_128M;
377 } else {
378 min_size = 128;
379 flag |= OB_LO_IO;
382 if (size >= min_size)
383 mask = ~(size - 1) | flag;
384 else
385 dev_warn(dev, "res size 0x%llx less than minimum 0x%x\n",
386 (u64)size, min_size);
388 xgene_pcie_writel(port, offset, lower_32_bits(cpu_addr));
389 xgene_pcie_writel(port, offset + 0x04, upper_32_bits(cpu_addr));
390 xgene_pcie_writel(port, offset + 0x08, lower_32_bits(mask));
391 xgene_pcie_writel(port, offset + 0x0c, upper_32_bits(mask));
392 xgene_pcie_writel(port, offset + 0x10, lower_32_bits(pci_addr));
393 xgene_pcie_writel(port, offset + 0x14, upper_32_bits(pci_addr));
396 static void xgene_pcie_setup_cfg_reg(struct xgene_pcie_port *port)
398 u64 addr = port->cfg_addr;
400 xgene_pcie_writel(port, CFGBARL, lower_32_bits(addr));
401 xgene_pcie_writel(port, CFGBARH, upper_32_bits(addr));
402 xgene_pcie_writel(port, CFGCTL, EN_REG);
405 static int xgene_pcie_map_ranges(struct xgene_pcie_port *port)
407 struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
408 struct resource_entry *window;
409 struct device *dev = port->dev;
411 resource_list_for_each_entry(window, &bridge->windows) {
412 struct resource *res = window->res;
413 u64 restype = resource_type(res);
415 dev_dbg(dev, "%pR\n", res);
417 switch (restype) {
418 case IORESOURCE_IO:
419 xgene_pcie_setup_ob_reg(port, res, OMR3BARL,
420 pci_pio_to_address(res->start),
421 res->start - window->offset);
422 break;
423 case IORESOURCE_MEM:
424 if (res->flags & IORESOURCE_PREFETCH)
425 xgene_pcie_setup_ob_reg(port, res, OMR2BARL,
426 res->start,
427 res->start -
428 window->offset);
429 else
430 xgene_pcie_setup_ob_reg(port, res, OMR1BARL,
431 res->start,
432 res->start -
433 window->offset);
434 break;
435 case IORESOURCE_BUS:
436 break;
437 default:
438 dev_err(dev, "invalid resource %pR\n", res);
439 return -EINVAL;
442 xgene_pcie_setup_cfg_reg(port);
443 return 0;
446 static void xgene_pcie_setup_pims(struct xgene_pcie_port *port, u32 pim_reg,
447 u64 pim, u64 size)
449 xgene_pcie_writel(port, pim_reg, lower_32_bits(pim));
450 xgene_pcie_writel(port, pim_reg + 0x04,
451 upper_32_bits(pim) | EN_COHERENCY);
452 xgene_pcie_writel(port, pim_reg + 0x10, lower_32_bits(size));
453 xgene_pcie_writel(port, pim_reg + 0x14, upper_32_bits(size));
457 * X-Gene PCIe support maximum 3 inbound memory regions
458 * This function helps to select a region based on size of region
460 static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
462 if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) {
463 *ib_reg_mask |= (1 << 1);
464 return 1;
467 if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
468 *ib_reg_mask |= (1 << 0);
469 return 0;
472 if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) {
473 *ib_reg_mask |= (1 << 2);
474 return 2;
477 return -EINVAL;
480 static void xgene_pcie_setup_ib_reg(struct xgene_pcie_port *port,
481 struct resource_entry *entry,
482 u8 *ib_reg_mask)
484 void __iomem *cfg_base = port->cfg_base;
485 struct device *dev = port->dev;
486 void *bar_addr;
487 u32 pim_reg;
488 u64 cpu_addr = entry->res->start;
489 u64 pci_addr = cpu_addr - entry->offset;
490 u64 size = resource_size(entry->res);
491 u64 mask = ~(size - 1) | EN_REG;
492 u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
493 u32 bar_low;
494 int region;
496 region = xgene_pcie_select_ib_reg(ib_reg_mask, size);
497 if (region < 0) {
498 dev_warn(dev, "invalid pcie dma-range config\n");
499 return;
502 if (entry->res->flags & IORESOURCE_PREFETCH)
503 flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
505 bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
506 switch (region) {
507 case 0:
508 xgene_pcie_set_ib_mask(port, BRIDGE_CFG_4, flags, size);
509 bar_addr = cfg_base + PCI_BASE_ADDRESS_0;
510 writel(bar_low, bar_addr);
511 writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
512 pim_reg = PIM1_1L;
513 break;
514 case 1:
515 xgene_pcie_writel(port, IBAR2, bar_low);
516 xgene_pcie_writel(port, IR2MSK, lower_32_bits(mask));
517 pim_reg = PIM2_1L;
518 break;
519 case 2:
520 xgene_pcie_writel(port, IBAR3L, bar_low);
521 xgene_pcie_writel(port, IBAR3L + 0x4, upper_32_bits(cpu_addr));
522 xgene_pcie_writel(port, IR3MSKL, lower_32_bits(mask));
523 xgene_pcie_writel(port, IR3MSKL + 0x4, upper_32_bits(mask));
524 pim_reg = PIM3_1L;
525 break;
528 xgene_pcie_setup_pims(port, pim_reg, pci_addr, ~(size - 1));
531 static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie_port *port)
533 struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
534 struct resource_entry *entry;
535 u8 ib_reg_mask = 0;
537 resource_list_for_each_entry(entry, &bridge->dma_ranges)
538 xgene_pcie_setup_ib_reg(port, entry, &ib_reg_mask);
540 return 0;
543 /* clear BAR configuration which was done by firmware */
544 static void xgene_pcie_clear_config(struct xgene_pcie_port *port)
546 int i;
548 for (i = PIM1_1L; i <= CFGCTL; i += 4)
549 xgene_pcie_writel(port, i, 0);
552 static int xgene_pcie_setup(struct xgene_pcie_port *port)
554 struct device *dev = port->dev;
555 u32 val, lanes = 0, speed = 0;
556 int ret;
558 xgene_pcie_clear_config(port);
560 /* setup the vendor and device IDs correctly */
561 val = (XGENE_PCIE_DEVICEID << 16) | XGENE_PCIE_VENDORID;
562 xgene_pcie_writel(port, BRIDGE_CFG_0, val);
564 ret = xgene_pcie_map_ranges(port);
565 if (ret)
566 return ret;
568 ret = xgene_pcie_parse_map_dma_ranges(port);
569 if (ret)
570 return ret;
572 xgene_pcie_linkup(port, &lanes, &speed);
573 if (!port->link_up)
574 dev_info(dev, "(rc) link down\n");
575 else
576 dev_info(dev, "(rc) x%d gen-%d link up\n", lanes, speed + 1);
577 return 0;
580 static struct pci_ops xgene_pcie_ops = {
581 .map_bus = xgene_pcie_map_bus,
582 .read = xgene_pcie_config_read32,
583 .write = pci_generic_config_write32,
586 static int xgene_pcie_probe(struct platform_device *pdev)
588 struct device *dev = &pdev->dev;
589 struct device_node *dn = dev->of_node;
590 struct xgene_pcie_port *port;
591 struct pci_host_bridge *bridge;
592 int ret;
594 bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
595 if (!bridge)
596 return -ENOMEM;
598 port = pci_host_bridge_priv(bridge);
600 port->node = of_node_get(dn);
601 port->dev = dev;
603 port->version = XGENE_PCIE_IP_VER_UNKN;
604 if (of_device_is_compatible(port->node, "apm,xgene-pcie"))
605 port->version = XGENE_PCIE_IP_VER_1;
607 ret = xgene_pcie_map_reg(port, pdev);
608 if (ret)
609 return ret;
611 ret = xgene_pcie_init_port(port);
612 if (ret)
613 return ret;
615 ret = xgene_pcie_setup(port);
616 if (ret)
617 return ret;
619 bridge->sysdata = port;
620 bridge->ops = &xgene_pcie_ops;
622 return pci_host_probe(bridge);
625 static const struct of_device_id xgene_pcie_match_table[] = {
626 {.compatible = "apm,xgene-pcie",},
630 static struct platform_driver xgene_pcie_driver = {
631 .driver = {
632 .name = "xgene-pcie",
633 .of_match_table = of_match_ptr(xgene_pcie_match_table),
634 .suppress_bind_attrs = true,
636 .probe = xgene_pcie_probe,
638 builtin_platform_driver(xgene_pcie_driver);
639 #endif