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v6.8
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * APM X-Gene PCIe Driver
  4 *
  5 * Copyright (c) 2014 Applied Micro Circuits Corporation.
  6 *
  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_pci.h>
 18#include <linux/pci.h>
 19#include <linux/pci-acpi.h>
 20#include <linux/pci-ecam.h>
 21#include <linux/platform_device.h>
 22#include <linux/slab.h>
 23
 24#include "../pci.h"
 25
 26#define PCIECORE_CTLANDSTATUS		0x50
 27#define PIM1_1L				0x80
 28#define IBAR2				0x98
 29#define IR2MSK				0x9c
 30#define PIM2_1L				0xa0
 31#define IBAR3L				0xb4
 32#define IR3MSKL				0xbc
 33#define PIM3_1L				0xc4
 34#define OMR1BARL			0x100
 35#define OMR2BARL			0x118
 36#define OMR3BARL			0x130
 37#define CFGBARL				0x154
 38#define CFGBARH				0x158
 39#define CFGCTL				0x15c
 40#define RTDID				0x160
 41#define BRIDGE_CFG_0			0x2000
 42#define BRIDGE_CFG_4			0x2010
 43#define BRIDGE_STATUS_0			0x2600
 44
 45#define LINK_UP_MASK			0x00000100
 46#define AXI_EP_CFG_ACCESS		0x10000
 47#define EN_COHERENCY			0xF0000000
 48#define EN_REG				0x00000001
 49#define OB_LO_IO			0x00000002
 
 50#define XGENE_PCIE_DEVICEID		0xE004
 
 51#define PIPE_PHY_RATE_RD(src)		((0xc000 & (u32)(src)) >> 0xe)
 52
 53#define XGENE_V1_PCI_EXP_CAP		0x40
 54
 55/* PCIe IP version */
 56#define XGENE_PCIE_IP_VER_UNKN		0
 57#define XGENE_PCIE_IP_VER_1		1
 58#define XGENE_PCIE_IP_VER_2		2
 59
 60#if defined(CONFIG_PCI_XGENE) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
 61struct xgene_pcie {
 62	struct device_node	*node;
 63	struct device		*dev;
 64	struct clk		*clk;
 65	void __iomem		*csr_base;
 66	void __iomem		*cfg_base;
 67	unsigned long		cfg_addr;
 68	bool			link_up;
 69	u32			version;
 70};
 71
 72static u32 xgene_pcie_readl(struct xgene_pcie *port, u32 reg)
 73{
 74	return readl(port->csr_base + reg);
 75}
 76
 77static void xgene_pcie_writel(struct xgene_pcie *port, u32 reg, u32 val)
 78{
 79	writel(val, port->csr_base + reg);
 80}
 81
 82static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
 83{
 84	return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags;
 85}
 86
 87static inline struct xgene_pcie *pcie_bus_to_port(struct pci_bus *bus)
 88{
 89	struct pci_config_window *cfg;
 90
 91	if (acpi_disabled)
 92		return (struct xgene_pcie *)(bus->sysdata);
 93
 94	cfg = bus->sysdata;
 95	return (struct xgene_pcie *)(cfg->priv);
 96}
 97
 98/*
 99 * When the address bit [17:16] is 2'b01, the Configuration access will be
100 * treated as Type 1 and it will be forwarded to external PCIe device.
101 */
102static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
103{
104	struct xgene_pcie *port = pcie_bus_to_port(bus);
105
106	if (bus->number >= (bus->primary + 1))
107		return port->cfg_base + AXI_EP_CFG_ACCESS;
108
109	return port->cfg_base;
110}
111
112/*
113 * For Configuration request, RTDID register is used as Bus Number,
114 * Device Number and Function number of the header fields.
115 */
116static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
117{
118	struct xgene_pcie *port = pcie_bus_to_port(bus);
119	unsigned int b, d, f;
120	u32 rtdid_val = 0;
121
122	b = bus->number;
123	d = PCI_SLOT(devfn);
124	f = PCI_FUNC(devfn);
125
126	if (!pci_is_root_bus(bus))
127		rtdid_val = (b << 8) | (d << 3) | f;
128
129	xgene_pcie_writel(port, RTDID, rtdid_val);
130	/* read the register back to ensure flush */
131	xgene_pcie_readl(port, RTDID);
132}
133
134/*
135 * X-Gene PCIe port uses BAR0-BAR1 of RC's configuration space as
136 * the translation from PCI bus to native BUS.  Entire DDR region
137 * is mapped into PCIe space using these registers, so it can be
138 * reached by DMA from EP devices.  The BAR0/1 of bridge should be
139 * hidden during enumeration to avoid the sizing and resource allocation
140 * by PCIe core.
141 */
142static bool xgene_pcie_hide_rc_bars(struct pci_bus *bus, int offset)
143{
144	if (pci_is_root_bus(bus) && ((offset == PCI_BASE_ADDRESS_0) ||
145				     (offset == PCI_BASE_ADDRESS_1)))
146		return true;
147
148	return false;
149}
150
151static void __iomem *xgene_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
152					int offset)
153{
154	if ((pci_is_root_bus(bus) && devfn != 0) ||
155	    xgene_pcie_hide_rc_bars(bus, offset))
156		return NULL;
157
158	xgene_pcie_set_rtdid_reg(bus, devfn);
159	return xgene_pcie_get_cfg_base(bus) + offset;
160}
161
162static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
163				    int where, int size, u32 *val)
164{
165	struct xgene_pcie *port = pcie_bus_to_port(bus);
166	int ret;
167
168	ret = pci_generic_config_read32(bus, devfn, where & ~0x3, 4, val);
169	if (ret != PCIBIOS_SUCCESSFUL)
170		return ret;
171
172	/*
173	 * The v1 controller has a bug in its Configuration Request Retry
174	 * Status (CRS) logic: when CRS Software Visibility is enabled and
175	 * we read the Vendor and Device ID of a non-existent device, the
176	 * controller fabricates return data of 0xFFFF0001 ("device exists
177	 * but is not ready") instead of 0xFFFFFFFF (PCI_ERROR_RESPONSE)
178	 * ("device does not exist").  This causes the PCI core to retry
179	 * the read until it times out.  Avoid this by not claiming to
180	 * support CRS SV.
181	 */
182	if (pci_is_root_bus(bus) && (port->version == XGENE_PCIE_IP_VER_1) &&
183	    ((where & ~0x3) == XGENE_V1_PCI_EXP_CAP + PCI_EXP_RTCTL))
184		*val &= ~(PCI_EXP_RTCAP_CRSVIS << 16);
185
186	if (size <= 2)
187		*val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1);
188
189	return PCIBIOS_SUCCESSFUL;
190}
191#endif
192
193#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
194static int xgene_get_csr_resource(struct acpi_device *adev,
195				  struct resource *res)
196{
197	struct device *dev = &adev->dev;
198	struct resource_entry *entry;
199	struct list_head list;
200	unsigned long flags;
201	int ret;
202
203	INIT_LIST_HEAD(&list);
204	flags = IORESOURCE_MEM;
205	ret = acpi_dev_get_resources(adev, &list,
206				     acpi_dev_filter_resource_type_cb,
207				     (void *) flags);
208	if (ret < 0) {
209		dev_err(dev, "failed to parse _CRS method, error code %d\n",
210			ret);
211		return ret;
212	}
213
214	if (ret == 0) {
215		dev_err(dev, "no IO and memory resources present in _CRS\n");
216		return -EINVAL;
217	}
218
219	entry = list_first_entry(&list, struct resource_entry, node);
220	*res = *entry->res;
221	acpi_dev_free_resource_list(&list);
222	return 0;
223}
224
225static int xgene_pcie_ecam_init(struct pci_config_window *cfg, u32 ipversion)
226{
227	struct device *dev = cfg->parent;
228	struct acpi_device *adev = to_acpi_device(dev);
229	struct xgene_pcie *port;
230	struct resource csr;
231	int ret;
232
233	port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
234	if (!port)
235		return -ENOMEM;
236
237	ret = xgene_get_csr_resource(adev, &csr);
238	if (ret) {
239		dev_err(dev, "can't get CSR resource\n");
240		return ret;
241	}
242	port->csr_base = devm_pci_remap_cfg_resource(dev, &csr);
243	if (IS_ERR(port->csr_base))
244		return PTR_ERR(port->csr_base);
245
246	port->cfg_base = cfg->win;
247	port->version = ipversion;
248
249	cfg->priv = port;
250	return 0;
251}
252
253static int xgene_v1_pcie_ecam_init(struct pci_config_window *cfg)
254{
255	return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_1);
256}
257
258const struct pci_ecam_ops xgene_v1_pcie_ecam_ops = {
 
259	.init		= xgene_v1_pcie_ecam_init,
260	.pci_ops	= {
261		.map_bus	= xgene_pcie_map_bus,
262		.read		= xgene_pcie_config_read32,
263		.write		= pci_generic_config_write,
264	}
265};
266
267static int xgene_v2_pcie_ecam_init(struct pci_config_window *cfg)
268{
269	return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_2);
270}
271
272const struct pci_ecam_ops xgene_v2_pcie_ecam_ops = {
 
273	.init		= xgene_v2_pcie_ecam_init,
274	.pci_ops	= {
275		.map_bus	= xgene_pcie_map_bus,
276		.read		= xgene_pcie_config_read32,
277		.write		= pci_generic_config_write,
278	}
279};
280#endif
281
282#if defined(CONFIG_PCI_XGENE)
283static u64 xgene_pcie_set_ib_mask(struct xgene_pcie *port, u32 addr,
284				  u32 flags, u64 size)
285{
286	u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags;
287	u32 val32 = 0;
288	u32 val;
289
290	val32 = xgene_pcie_readl(port, addr);
291	val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16);
292	xgene_pcie_writel(port, addr, val);
293
294	val32 = xgene_pcie_readl(port, addr + 0x04);
295	val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16);
296	xgene_pcie_writel(port, addr + 0x04, val);
297
298	val32 = xgene_pcie_readl(port, addr + 0x04);
299	val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16);
300	xgene_pcie_writel(port, addr + 0x04, val);
301
302	val32 = xgene_pcie_readl(port, addr + 0x08);
303	val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16);
304	xgene_pcie_writel(port, addr + 0x08, val);
305
306	return mask;
307}
308
309static void xgene_pcie_linkup(struct xgene_pcie *port,
310			      u32 *lanes, u32 *speed)
311{
312	u32 val32;
313
314	port->link_up = false;
315	val32 = xgene_pcie_readl(port, PCIECORE_CTLANDSTATUS);
316	if (val32 & LINK_UP_MASK) {
317		port->link_up = true;
318		*speed = PIPE_PHY_RATE_RD(val32);
319		val32 = xgene_pcie_readl(port, BRIDGE_STATUS_0);
320		*lanes = val32 >> 26;
321	}
322}
323
324static int xgene_pcie_init_port(struct xgene_pcie *port)
325{
326	struct device *dev = port->dev;
327	int rc;
328
329	port->clk = clk_get(dev, NULL);
330	if (IS_ERR(port->clk)) {
331		dev_err(dev, "clock not available\n");
332		return -ENODEV;
333	}
334
335	rc = clk_prepare_enable(port->clk);
336	if (rc) {
337		dev_err(dev, "clock enable failed\n");
338		return rc;
339	}
340
341	return 0;
342}
343
344static int xgene_pcie_map_reg(struct xgene_pcie *port,
345			      struct platform_device *pdev)
346{
347	struct device *dev = port->dev;
348	struct resource *res;
349
350	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr");
351	port->csr_base = devm_pci_remap_cfg_resource(dev, res);
352	if (IS_ERR(port->csr_base))
353		return PTR_ERR(port->csr_base);
354
355	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
356	port->cfg_base = devm_ioremap_resource(dev, res);
357	if (IS_ERR(port->cfg_base))
358		return PTR_ERR(port->cfg_base);
359	port->cfg_addr = res->start;
360
361	return 0;
362}
363
364static void xgene_pcie_setup_ob_reg(struct xgene_pcie *port,
365				    struct resource *res, u32 offset,
366				    u64 cpu_addr, u64 pci_addr)
367{
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;
374
375	if (restype == IORESOURCE_MEM) {
376		min_size = SZ_128M;
377	} else {
378		min_size = 128;
379		flag |= OB_LO_IO;
380	}
381
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);
387
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));
394}
395
396static void xgene_pcie_setup_cfg_reg(struct xgene_pcie *port)
397{
398	u64 addr = port->cfg_addr;
399
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);
403}
404
405static int xgene_pcie_map_ranges(struct xgene_pcie *port)
406{
407	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
408	struct resource_entry *window;
409	struct device *dev = port->dev;
410
411	resource_list_for_each_entry(window, &bridge->windows) {
412		struct resource *res = window->res;
413		u64 restype = resource_type(res);
414
415		dev_dbg(dev, "%pR\n", res);
416
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;
440		}
441	}
442	xgene_pcie_setup_cfg_reg(port);
443	return 0;
444}
445
446static void xgene_pcie_setup_pims(struct xgene_pcie *port, u32 pim_reg,
447				  u64 pim, u64 size)
448{
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));
454}
455
456/*
457 * X-Gene PCIe support maximum 3 inbound memory regions
458 * This function helps to select a region based on size of region
459 */
460static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
461{
462	if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) {
463		*ib_reg_mask |= (1 << 1);
464		return 1;
465	}
466
467	if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
468		*ib_reg_mask |= (1 << 0);
469		return 0;
470	}
471
472	if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) {
473		*ib_reg_mask |= (1 << 2);
474		return 2;
475	}
476
477	return -EINVAL;
478}
479
480static void xgene_pcie_setup_ib_reg(struct xgene_pcie *port,
481				    struct of_pci_range *range, u8 *ib_reg_mask)
 
482{
483	void __iomem *cfg_base = port->cfg_base;
484	struct device *dev = port->dev;
485	void __iomem *bar_addr;
486	u32 pim_reg;
487	u64 cpu_addr = range->cpu_addr;
488	u64 pci_addr = range->pci_addr;
489	u64 size = range->size;
490	u64 mask = ~(size - 1) | EN_REG;
491	u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
492	u32 bar_low;
493	int region;
494
495	region = xgene_pcie_select_ib_reg(ib_reg_mask, range->size);
496	if (region < 0) {
497		dev_warn(dev, "invalid pcie dma-range config\n");
498		return;
499	}
500
501	if (range->flags & IORESOURCE_PREFETCH)
502		flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
503
504	bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
505	switch (region) {
506	case 0:
507		xgene_pcie_set_ib_mask(port, BRIDGE_CFG_4, flags, size);
508		bar_addr = cfg_base + PCI_BASE_ADDRESS_0;
509		writel(bar_low, bar_addr);
510		writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
511		pim_reg = PIM1_1L;
512		break;
513	case 1:
514		xgene_pcie_writel(port, IBAR2, bar_low);
515		xgene_pcie_writel(port, IR2MSK, lower_32_bits(mask));
516		pim_reg = PIM2_1L;
517		break;
518	case 2:
519		xgene_pcie_writel(port, IBAR3L, bar_low);
520		xgene_pcie_writel(port, IBAR3L + 0x4, upper_32_bits(cpu_addr));
521		xgene_pcie_writel(port, IR3MSKL, lower_32_bits(mask));
522		xgene_pcie_writel(port, IR3MSKL + 0x4, upper_32_bits(mask));
523		pim_reg = PIM3_1L;
524		break;
525	}
526
527	xgene_pcie_setup_pims(port, pim_reg, pci_addr, ~(size - 1));
528}
529
530static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie *port)
531{
532	struct device_node *np = port->node;
533	struct of_pci_range range;
534	struct of_pci_range_parser parser;
535	struct device *dev = port->dev;
536	u8 ib_reg_mask = 0;
537
538	if (of_pci_dma_range_parser_init(&parser, np)) {
539		dev_err(dev, "missing dma-ranges property\n");
540		return -EINVAL;
541	}
542
543	/* Get the dma-ranges from DT */
544	for_each_of_pci_range(&parser, &range) {
545		u64 end = range.cpu_addr + range.size - 1;
546
547		dev_dbg(dev, "0x%08x 0x%016llx..0x%016llx -> 0x%016llx\n",
548			range.flags, range.cpu_addr, end, range.pci_addr);
549		xgene_pcie_setup_ib_reg(port, &range, &ib_reg_mask);
550	}
551	return 0;
552}
553
554/* clear BAR configuration which was done by firmware */
555static void xgene_pcie_clear_config(struct xgene_pcie *port)
556{
557	int i;
558
559	for (i = PIM1_1L; i <= CFGCTL; i += 4)
560		xgene_pcie_writel(port, i, 0);
561}
562
563static int xgene_pcie_setup(struct xgene_pcie *port)
564{
565	struct device *dev = port->dev;
566	u32 val, lanes = 0, speed = 0;
567	int ret;
568
569	xgene_pcie_clear_config(port);
570
571	/* setup the vendor and device IDs correctly */
572	val = (XGENE_PCIE_DEVICEID << 16) | PCI_VENDOR_ID_AMCC;
573	xgene_pcie_writel(port, BRIDGE_CFG_0, val);
574
575	ret = xgene_pcie_map_ranges(port);
576	if (ret)
577		return ret;
578
579	ret = xgene_pcie_parse_map_dma_ranges(port);
580	if (ret)
581		return ret;
582
583	xgene_pcie_linkup(port, &lanes, &speed);
584	if (!port->link_up)
585		dev_info(dev, "(rc) link down\n");
586	else
587		dev_info(dev, "(rc) x%d gen-%d link up\n", lanes, speed + 1);
588	return 0;
589}
590
591static struct pci_ops xgene_pcie_ops = {
592	.map_bus = xgene_pcie_map_bus,
593	.read = xgene_pcie_config_read32,
594	.write = pci_generic_config_write32,
595};
596
597static int xgene_pcie_probe(struct platform_device *pdev)
598{
599	struct device *dev = &pdev->dev;
600	struct device_node *dn = dev->of_node;
601	struct xgene_pcie *port;
602	struct pci_host_bridge *bridge;
603	int ret;
604
605	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
606	if (!bridge)
607		return -ENOMEM;
608
609	port = pci_host_bridge_priv(bridge);
610
611	port->node = of_node_get(dn);
612	port->dev = dev;
613
614	port->version = XGENE_PCIE_IP_VER_UNKN;
615	if (of_device_is_compatible(port->node, "apm,xgene-pcie"))
616		port->version = XGENE_PCIE_IP_VER_1;
617
618	ret = xgene_pcie_map_reg(port, pdev);
619	if (ret)
620		return ret;
621
622	ret = xgene_pcie_init_port(port);
623	if (ret)
624		return ret;
625
626	ret = xgene_pcie_setup(port);
627	if (ret)
628		return ret;
629
630	bridge->sysdata = port;
631	bridge->ops = &xgene_pcie_ops;
632
633	return pci_host_probe(bridge);
634}
635
636static const struct of_device_id xgene_pcie_match_table[] = {
637	{.compatible = "apm,xgene-pcie",},
638	{},
639};
640
641static struct platform_driver xgene_pcie_driver = {
642	.driver = {
643		.name = "xgene-pcie",
644		.of_match_table = xgene_pcie_match_table,
645		.suppress_bind_attrs = true,
646	},
647	.probe = xgene_pcie_probe,
648};
649builtin_platform_driver(xgene_pcie_driver);
650#endif
v5.9
  1// SPDX-License-Identifier: GPL-2.0+
  2/**
  3 * APM X-Gene PCIe Driver
  4 *
  5 * Copyright (c) 2014 Applied Micro Circuits Corporation.
  6 *
  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>
 24
 25#include "../pci.h"
 26
 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
 45
 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)
 55
 56#define XGENE_V1_PCI_EXP_CAP		0x40
 57
 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
 62
 63#if defined(CONFIG_PCI_XGENE) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
 64struct 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;
 73};
 74
 75static u32 xgene_pcie_readl(struct xgene_pcie_port *port, u32 reg)
 76{
 77	return readl(port->csr_base + reg);
 78}
 79
 80static void xgene_pcie_writel(struct xgene_pcie_port *port, u32 reg, u32 val)
 81{
 82	writel(val, port->csr_base + reg);
 83}
 84
 85static inline u32 pcie_bar_low_val(u32 addr, u32 flags)
 86{
 87	return (addr & PCI_BASE_ADDRESS_MEM_MASK) | flags;
 88}
 89
 90static inline struct xgene_pcie_port *pcie_bus_to_port(struct pci_bus *bus)
 91{
 92	struct pci_config_window *cfg;
 93
 94	if (acpi_disabled)
 95		return (struct xgene_pcie_port *)(bus->sysdata);
 96
 97	cfg = bus->sysdata;
 98	return (struct xgene_pcie_port *)(cfg->priv);
 99}
100
101/*
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.
104 */
105static void __iomem *xgene_pcie_get_cfg_base(struct pci_bus *bus)
106{
107	struct xgene_pcie_port *port = pcie_bus_to_port(bus);
108
109	if (bus->number >= (bus->primary + 1))
110		return port->cfg_base + AXI_EP_CFG_ACCESS;
111
112	return port->cfg_base;
113}
114
115/*
116 * For Configuration request, RTDID register is used as Bus Number,
117 * Device Number and Function number of the header fields.
118 */
119static void xgene_pcie_set_rtdid_reg(struct pci_bus *bus, uint devfn)
120{
121	struct xgene_pcie_port *port = pcie_bus_to_port(bus);
122	unsigned int b, d, f;
123	u32 rtdid_val = 0;
124
125	b = bus->number;
126	d = PCI_SLOT(devfn);
127	f = PCI_FUNC(devfn);
128
129	if (!pci_is_root_bus(bus))
130		rtdid_val = (b << 8) | (d << 3) | f;
131
132	xgene_pcie_writel(port, RTDID, rtdid_val);
133	/* read the register back to ensure flush */
134	xgene_pcie_readl(port, RTDID);
135}
136
137/*
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.
144 */
145static bool xgene_pcie_hide_rc_bars(struct pci_bus *bus, int offset)
146{
147	if (pci_is_root_bus(bus) && ((offset == PCI_BASE_ADDRESS_0) ||
148				     (offset == PCI_BASE_ADDRESS_1)))
149		return true;
150
151	return false;
152}
153
154static void __iomem *xgene_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
155					int offset)
156{
157	if ((pci_is_root_bus(bus) && devfn != 0) ||
158	    xgene_pcie_hide_rc_bars(bus, offset))
159		return NULL;
160
161	xgene_pcie_set_rtdid_reg(bus, devfn);
162	return xgene_pcie_get_cfg_base(bus) + offset;
163}
164
165static int xgene_pcie_config_read32(struct pci_bus *bus, unsigned int devfn,
166				    int where, int size, u32 *val)
167{
168	struct xgene_pcie_port *port = pcie_bus_to_port(bus);
 
169
170	if (pci_generic_config_read32(bus, devfn, where & ~0x3, 4, val) !=
171	    PCIBIOS_SUCCESSFUL)
172		return PCIBIOS_DEVICE_NOT_FOUND;
173
174	/*
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.
 
182	 */
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);
186
187	if (size <= 2)
188		*val = (*val >> (8 * (where & 3))) & ((1 << (size * 8)) - 1);
189
190	return PCIBIOS_SUCCESSFUL;
191}
192#endif
193
194#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
195static int xgene_get_csr_resource(struct acpi_device *adev,
196				  struct resource *res)
197{
198	struct device *dev = &adev->dev;
199	struct resource_entry *entry;
200	struct list_head list;
201	unsigned long flags;
202	int ret;
203
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;
213	}
214
215	if (ret == 0) {
216		dev_err(dev, "no IO and memory resources present in _CRS\n");
217		return -EINVAL;
218	}
219
220	entry = list_first_entry(&list, struct resource_entry, node);
221	*res = *entry->res;
222	acpi_dev_free_resource_list(&list);
223	return 0;
224}
225
226static int xgene_pcie_ecam_init(struct pci_config_window *cfg, u32 ipversion)
227{
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;
233
234	port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
235	if (!port)
236		return -ENOMEM;
237
238	ret = xgene_get_csr_resource(adev, &csr);
239	if (ret) {
240		dev_err(dev, "can't get CSR resource\n");
241		return ret;
242	}
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);
246
247	port->cfg_base = cfg->win;
248	port->version = ipversion;
249
250	cfg->priv = port;
251	return 0;
252}
253
254static int xgene_v1_pcie_ecam_init(struct pci_config_window *cfg)
255{
256	return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_1);
257}
258
259const struct pci_ecam_ops xgene_v1_pcie_ecam_ops = {
260	.bus_shift	= 16,
261	.init		= xgene_v1_pcie_ecam_init,
262	.pci_ops	= {
263		.map_bus	= xgene_pcie_map_bus,
264		.read		= xgene_pcie_config_read32,
265		.write		= pci_generic_config_write,
266	}
267};
268
269static int xgene_v2_pcie_ecam_init(struct pci_config_window *cfg)
270{
271	return xgene_pcie_ecam_init(cfg, XGENE_PCIE_IP_VER_2);
272}
273
274const struct pci_ecam_ops xgene_v2_pcie_ecam_ops = {
275	.bus_shift	= 16,
276	.init		= xgene_v2_pcie_ecam_init,
277	.pci_ops	= {
278		.map_bus	= xgene_pcie_map_bus,
279		.read		= xgene_pcie_config_read32,
280		.write		= pci_generic_config_write,
281	}
282};
283#endif
284
285#if defined(CONFIG_PCI_XGENE)
286static u64 xgene_pcie_set_ib_mask(struct xgene_pcie_port *port, u32 addr,
287				  u32 flags, u64 size)
288{
289	u64 mask = (~(size - 1) & PCI_BASE_ADDRESS_MEM_MASK) | flags;
290	u32 val32 = 0;
291	u32 val;
292
293	val32 = xgene_pcie_readl(port, addr);
294	val = (val32 & 0x0000ffff) | (lower_32_bits(mask) << 16);
295	xgene_pcie_writel(port, addr, val);
296
297	val32 = xgene_pcie_readl(port, addr + 0x04);
298	val = (val32 & 0xffff0000) | (lower_32_bits(mask) >> 16);
299	xgene_pcie_writel(port, addr + 0x04, val);
300
301	val32 = xgene_pcie_readl(port, addr + 0x04);
302	val = (val32 & 0x0000ffff) | (upper_32_bits(mask) << 16);
303	xgene_pcie_writel(port, addr + 0x04, val);
304
305	val32 = xgene_pcie_readl(port, addr + 0x08);
306	val = (val32 & 0xffff0000) | (upper_32_bits(mask) >> 16);
307	xgene_pcie_writel(port, addr + 0x08, val);
308
309	return mask;
310}
311
312static void xgene_pcie_linkup(struct xgene_pcie_port *port,
313			      u32 *lanes, u32 *speed)
314{
315	u32 val32;
316
317	port->link_up = false;
318	val32 = xgene_pcie_readl(port, PCIECORE_CTLANDSTATUS);
319	if (val32 & LINK_UP_MASK) {
320		port->link_up = true;
321		*speed = PIPE_PHY_RATE_RD(val32);
322		val32 = xgene_pcie_readl(port, BRIDGE_STATUS_0);
323		*lanes = val32 >> 26;
324	}
325}
326
327static int xgene_pcie_init_port(struct xgene_pcie_port *port)
328{
329	struct device *dev = port->dev;
330	int rc;
331
332	port->clk = clk_get(dev, NULL);
333	if (IS_ERR(port->clk)) {
334		dev_err(dev, "clock not available\n");
335		return -ENODEV;
336	}
337
338	rc = clk_prepare_enable(port->clk);
339	if (rc) {
340		dev_err(dev, "clock enable failed\n");
341		return rc;
342	}
343
344	return 0;
345}
346
347static int xgene_pcie_map_reg(struct xgene_pcie_port *port,
348			      struct platform_device *pdev)
349{
350	struct device *dev = port->dev;
351	struct resource *res;
352
353	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "csr");
354	port->csr_base = devm_pci_remap_cfg_resource(dev, res);
355	if (IS_ERR(port->csr_base))
356		return PTR_ERR(port->csr_base);
357
358	port->cfg_base = devm_platform_ioremap_resource_byname(pdev, "cfg");
 
359	if (IS_ERR(port->cfg_base))
360		return PTR_ERR(port->cfg_base);
361	port->cfg_addr = res->start;
362
363	return 0;
364}
365
366static void xgene_pcie_setup_ob_reg(struct xgene_pcie_port *port,
367				    struct resource *res, u32 offset,
368				    u64 cpu_addr, u64 pci_addr)
369{
370	struct device *dev = port->dev;
371	resource_size_t size = resource_size(res);
372	u64 restype = resource_type(res);
373	u64 mask = 0;
374	u32 min_size;
375	u32 flag = EN_REG;
376
377	if (restype == IORESOURCE_MEM) {
378		min_size = SZ_128M;
379	} else {
380		min_size = 128;
381		flag |= OB_LO_IO;
382	}
383
384	if (size >= min_size)
385		mask = ~(size - 1) | flag;
386	else
387		dev_warn(dev, "res size 0x%llx less than minimum 0x%x\n",
388			 (u64)size, min_size);
389
390	xgene_pcie_writel(port, offset, lower_32_bits(cpu_addr));
391	xgene_pcie_writel(port, offset + 0x04, upper_32_bits(cpu_addr));
392	xgene_pcie_writel(port, offset + 0x08, lower_32_bits(mask));
393	xgene_pcie_writel(port, offset + 0x0c, upper_32_bits(mask));
394	xgene_pcie_writel(port, offset + 0x10, lower_32_bits(pci_addr));
395	xgene_pcie_writel(port, offset + 0x14, upper_32_bits(pci_addr));
396}
397
398static void xgene_pcie_setup_cfg_reg(struct xgene_pcie_port *port)
399{
400	u64 addr = port->cfg_addr;
401
402	xgene_pcie_writel(port, CFGBARL, lower_32_bits(addr));
403	xgene_pcie_writel(port, CFGBARH, upper_32_bits(addr));
404	xgene_pcie_writel(port, CFGCTL, EN_REG);
405}
406
407static int xgene_pcie_map_ranges(struct xgene_pcie_port *port)
408{
409	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
410	struct resource_entry *window;
411	struct device *dev = port->dev;
412
413	resource_list_for_each_entry(window, &bridge->windows) {
414		struct resource *res = window->res;
415		u64 restype = resource_type(res);
416
417		dev_dbg(dev, "%pR\n", res);
418
419		switch (restype) {
420		case IORESOURCE_IO:
421			xgene_pcie_setup_ob_reg(port, res, OMR3BARL,
422						pci_pio_to_address(res->start),
423						res->start - window->offset);
424			break;
425		case IORESOURCE_MEM:
426			if (res->flags & IORESOURCE_PREFETCH)
427				xgene_pcie_setup_ob_reg(port, res, OMR2BARL,
428							res->start,
429							res->start -
430							window->offset);
431			else
432				xgene_pcie_setup_ob_reg(port, res, OMR1BARL,
433							res->start,
434							res->start -
435							window->offset);
436			break;
437		case IORESOURCE_BUS:
438			break;
439		default:
440			dev_err(dev, "invalid resource %pR\n", res);
441			return -EINVAL;
442		}
443	}
444	xgene_pcie_setup_cfg_reg(port);
445	return 0;
446}
447
448static void xgene_pcie_setup_pims(struct xgene_pcie_port *port, u32 pim_reg,
449				  u64 pim, u64 size)
450{
451	xgene_pcie_writel(port, pim_reg, lower_32_bits(pim));
452	xgene_pcie_writel(port, pim_reg + 0x04,
453			  upper_32_bits(pim) | EN_COHERENCY);
454	xgene_pcie_writel(port, pim_reg + 0x10, lower_32_bits(size));
455	xgene_pcie_writel(port, pim_reg + 0x14, upper_32_bits(size));
456}
457
458/*
459 * X-Gene PCIe support maximum 3 inbound memory regions
460 * This function helps to select a region based on size of region
461 */
462static int xgene_pcie_select_ib_reg(u8 *ib_reg_mask, u64 size)
463{
464	if ((size > 4) && (size < SZ_16M) && !(*ib_reg_mask & (1 << 1))) {
465		*ib_reg_mask |= (1 << 1);
466		return 1;
467	}
468
469	if ((size > SZ_1K) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 0))) {
470		*ib_reg_mask |= (1 << 0);
471		return 0;
472	}
473
474	if ((size > SZ_1M) && (size < SZ_1T) && !(*ib_reg_mask & (1 << 2))) {
475		*ib_reg_mask |= (1 << 2);
476		return 2;
477	}
478
479	return -EINVAL;
480}
481
482static void xgene_pcie_setup_ib_reg(struct xgene_pcie_port *port,
483				    struct resource_entry *entry,
484				    u8 *ib_reg_mask)
485{
486	void __iomem *cfg_base = port->cfg_base;
487	struct device *dev = port->dev;
488	void *bar_addr;
489	u32 pim_reg;
490	u64 cpu_addr = entry->res->start;
491	u64 pci_addr = cpu_addr - entry->offset;
492	u64 size = resource_size(entry->res);
493	u64 mask = ~(size - 1) | EN_REG;
494	u32 flags = PCI_BASE_ADDRESS_MEM_TYPE_64;
495	u32 bar_low;
496	int region;
497
498	region = xgene_pcie_select_ib_reg(ib_reg_mask, size);
499	if (region < 0) {
500		dev_warn(dev, "invalid pcie dma-range config\n");
501		return;
502	}
503
504	if (entry->res->flags & IORESOURCE_PREFETCH)
505		flags |= PCI_BASE_ADDRESS_MEM_PREFETCH;
506
507	bar_low = pcie_bar_low_val((u32)cpu_addr, flags);
508	switch (region) {
509	case 0:
510		xgene_pcie_set_ib_mask(port, BRIDGE_CFG_4, flags, size);
511		bar_addr = cfg_base + PCI_BASE_ADDRESS_0;
512		writel(bar_low, bar_addr);
513		writel(upper_32_bits(cpu_addr), bar_addr + 0x4);
514		pim_reg = PIM1_1L;
515		break;
516	case 1:
517		xgene_pcie_writel(port, IBAR2, bar_low);
518		xgene_pcie_writel(port, IR2MSK, lower_32_bits(mask));
519		pim_reg = PIM2_1L;
520		break;
521	case 2:
522		xgene_pcie_writel(port, IBAR3L, bar_low);
523		xgene_pcie_writel(port, IBAR3L + 0x4, upper_32_bits(cpu_addr));
524		xgene_pcie_writel(port, IR3MSKL, lower_32_bits(mask));
525		xgene_pcie_writel(port, IR3MSKL + 0x4, upper_32_bits(mask));
526		pim_reg = PIM3_1L;
527		break;
528	}
529
530	xgene_pcie_setup_pims(port, pim_reg, pci_addr, ~(size - 1));
531}
532
533static int xgene_pcie_parse_map_dma_ranges(struct xgene_pcie_port *port)
534{
535	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(port);
536	struct resource_entry *entry;
 
 
537	u8 ib_reg_mask = 0;
538
539	resource_list_for_each_entry(entry, &bridge->dma_ranges)
540		xgene_pcie_setup_ib_reg(port, entry, &ib_reg_mask);
 
 
541
 
 
 
 
 
 
 
 
542	return 0;
543}
544
545/* clear BAR configuration which was done by firmware */
546static void xgene_pcie_clear_config(struct xgene_pcie_port *port)
547{
548	int i;
549
550	for (i = PIM1_1L; i <= CFGCTL; i += 4)
551		xgene_pcie_writel(port, i, 0);
552}
553
554static int xgene_pcie_setup(struct xgene_pcie_port *port)
555{
556	struct device *dev = port->dev;
557	u32 val, lanes = 0, speed = 0;
558	int ret;
559
560	xgene_pcie_clear_config(port);
561
562	/* setup the vendor and device IDs correctly */
563	val = (XGENE_PCIE_DEVICEID << 16) | XGENE_PCIE_VENDORID;
564	xgene_pcie_writel(port, BRIDGE_CFG_0, val);
565
566	ret = xgene_pcie_map_ranges(port);
567	if (ret)
568		return ret;
569
570	ret = xgene_pcie_parse_map_dma_ranges(port);
571	if (ret)
572		return ret;
573
574	xgene_pcie_linkup(port, &lanes, &speed);
575	if (!port->link_up)
576		dev_info(dev, "(rc) link down\n");
577	else
578		dev_info(dev, "(rc) x%d gen-%d link up\n", lanes, speed + 1);
579	return 0;
580}
581
582static struct pci_ops xgene_pcie_ops = {
583	.map_bus = xgene_pcie_map_bus,
584	.read = xgene_pcie_config_read32,
585	.write = pci_generic_config_write32,
586};
587
588static int xgene_pcie_probe(struct platform_device *pdev)
589{
590	struct device *dev = &pdev->dev;
591	struct device_node *dn = dev->of_node;
592	struct xgene_pcie_port *port;
593	struct pci_host_bridge *bridge;
594	int ret;
595
596	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*port));
597	if (!bridge)
598		return -ENOMEM;
599
600	port = pci_host_bridge_priv(bridge);
601
602	port->node = of_node_get(dn);
603	port->dev = dev;
604
605	port->version = XGENE_PCIE_IP_VER_UNKN;
606	if (of_device_is_compatible(port->node, "apm,xgene-pcie"))
607		port->version = XGENE_PCIE_IP_VER_1;
608
609	ret = xgene_pcie_map_reg(port, pdev);
610	if (ret)
611		return ret;
612
613	ret = xgene_pcie_init_port(port);
614	if (ret)
615		return ret;
616
617	ret = xgene_pcie_setup(port);
618	if (ret)
619		return ret;
620
621	bridge->sysdata = port;
622	bridge->ops = &xgene_pcie_ops;
623
624	return pci_host_probe(bridge);
625}
626
627static const struct of_device_id xgene_pcie_match_table[] = {
628	{.compatible = "apm,xgene-pcie",},
629	{},
630};
631
632static struct platform_driver xgene_pcie_driver = {
633	.driver = {
634		.name = "xgene-pcie",
635		.of_match_table = of_match_ptr(xgene_pcie_match_table),
636		.suppress_bind_attrs = true,
637	},
638	.probe = xgene_pcie_probe,
639};
640builtin_platform_driver(xgene_pcie_driver);
641#endif