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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2015 - 2016 Cavium, Inc.
  4 */
  5
  6#include <linux/bitfield.h>
  7#include <linux/kernel.h>
  8#include <linux/init.h>
 
  9#include <linux/of_address.h>
 10#include <linux/of_pci.h>
 11#include <linux/pci-acpi.h>
 12#include <linux/pci-ecam.h>
 13#include <linux/platform_device.h>
 14#include "../pci.h"
 15
 16#if defined(CONFIG_PCI_HOST_THUNDER_PEM) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
 17
 18#define PEM_CFG_WR 0x28
 19#define PEM_CFG_RD 0x30
 20
 21struct thunder_pem_pci {
 22	u32		ea_entry[3];
 23	void __iomem	*pem_reg_base;
 24};
 25
 26static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn,
 27				   int where, int size, u32 *val)
 28{
 29	u64 read_val, tmp_val;
 30	struct pci_config_window *cfg = bus->sysdata;
 31	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
 32
 33	if (devfn != 0 || where >= 2048) {
 34		*val = ~0;
 35		return PCIBIOS_DEVICE_NOT_FOUND;
 36	}
 37
 38	/*
 39	 * 32-bit accesses only.  Write the address to the low order
 40	 * bits of PEM_CFG_RD, then trigger the read by reading back.
 41	 * The config data lands in the upper 32-bits of PEM_CFG_RD.
 42	 */
 43	read_val = where & ~3ull;
 44	writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
 45	read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
 46	read_val >>= 32;
 47
 48	/*
 49	 * The config space contains some garbage, fix it up.  Also
 50	 * synthesize an EA capability for the BAR used by MSI-X.
 51	 */
 52	switch (where & ~3) {
 53	case 0x40:
 54		read_val &= 0xffff00ff;
 55		read_val |= 0x00007000; /* Skip MSI CAP */
 56		break;
 57	case 0x70: /* Express Cap */
 58		/*
 59		 * Change PME interrupt to vector 2 on T88 where it
 60		 * reads as 0, else leave it alone.
 61		 */
 62		if (!(read_val & (0x1f << 25)))
 63			read_val |= (2u << 25);
 64		break;
 65	case 0xb0: /* MSI-X Cap */
 66		/* TableSize=2 or 4, Next Cap is EA */
 67		read_val &= 0xc00000ff;
 68		/*
 69		 * If Express Cap(0x70) raw PME vector reads as 0 we are on
 70		 * T88 and TableSize is reported as 4, else TableSize
 71		 * is 2.
 72		 */
 73		writeq(0x70, pem_pci->pem_reg_base + PEM_CFG_RD);
 74		tmp_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
 75		tmp_val >>= 32;
 76		if (!(tmp_val & (0x1f << 25)))
 77			read_val |= 0x0003bc00;
 78		else
 79			read_val |= 0x0001bc00;
 80		break;
 81	case 0xb4:
 82		/* Table offset=0, BIR=0 */
 83		read_val = 0x00000000;
 84		break;
 85	case 0xb8:
 86		/* BPA offset=0xf0000, BIR=0 */
 87		read_val = 0x000f0000;
 88		break;
 89	case 0xbc:
 90		/* EA, 1 entry, no next Cap */
 91		read_val = 0x00010014;
 92		break;
 93	case 0xc0:
 94		/* DW2 for type-1 */
 95		read_val = 0x00000000;
 96		break;
 97	case 0xc4:
 98		/* Entry BEI=0, PP=0x00, SP=0xff, ES=3 */
 99		read_val = 0x80ff0003;
100		break;
101	case 0xc8:
102		read_val = pem_pci->ea_entry[0];
103		break;
104	case 0xcc:
105		read_val = pem_pci->ea_entry[1];
106		break;
107	case 0xd0:
108		read_val = pem_pci->ea_entry[2];
109		break;
110	default:
111		break;
112	}
113	read_val >>= (8 * (where & 3));
114	switch (size) {
115	case 1:
116		read_val &= 0xff;
117		break;
118	case 2:
119		read_val &= 0xffff;
120		break;
121	default:
122		break;
123	}
124	*val = read_val;
125	return PCIBIOS_SUCCESSFUL;
126}
127
128static int thunder_pem_config_read(struct pci_bus *bus, unsigned int devfn,
129				   int where, int size, u32 *val)
130{
131	struct pci_config_window *cfg = bus->sysdata;
132
133	if (bus->number < cfg->busr.start ||
134	    bus->number > cfg->busr.end)
135		return PCIBIOS_DEVICE_NOT_FOUND;
136
137	/*
138	 * The first device on the bus is the PEM PCIe bridge.
139	 * Special case its config access.
140	 */
141	if (bus->number == cfg->busr.start)
142		return thunder_pem_bridge_read(bus, devfn, where, size, val);
143
144	return pci_generic_config_read(bus, devfn, where, size, val);
145}
146
147/*
148 * Some of the w1c_bits below also include read-only or non-writable
149 * reserved bits, this makes the code simpler and is OK as the bits
150 * are not affected by writing zeros to them.
151 */
152static u32 thunder_pem_bridge_w1c_bits(u64 where_aligned)
153{
154	u32 w1c_bits = 0;
155
156	switch (where_aligned) {
157	case 0x04: /* Command/Status */
158	case 0x1c: /* Base and I/O Limit/Secondary Status */
159		w1c_bits = 0xff000000;
160		break;
161	case 0x44: /* Power Management Control and Status */
162		w1c_bits = 0xfffffe00;
163		break;
164	case 0x78: /* Device Control/Device Status */
165	case 0x80: /* Link Control/Link Status */
166	case 0x88: /* Slot Control/Slot Status */
167	case 0x90: /* Root Status */
168	case 0xa0: /* Link Control 2 Registers/Link Status 2 */
169		w1c_bits = 0xffff0000;
170		break;
171	case 0x104: /* Uncorrectable Error Status */
172	case 0x110: /* Correctable Error Status */
173	case 0x130: /* Error Status */
174	case 0x160: /* Link Control 4 */
175		w1c_bits = 0xffffffff;
176		break;
177	default:
178		break;
179	}
180	return w1c_bits;
181}
182
183/* Some bits must be written to one so they appear to be read-only. */
184static u32 thunder_pem_bridge_w1_bits(u64 where_aligned)
185{
186	u32 w1_bits;
187
188	switch (where_aligned) {
189	case 0x1c: /* I/O Base / I/O Limit, Secondary Status */
190		/* Force 32-bit I/O addressing. */
191		w1_bits = 0x0101;
192		break;
193	case 0x24: /* Prefetchable Memory Base / Prefetchable Memory Limit */
194		/* Force 64-bit addressing */
195		w1_bits = 0x00010001;
196		break;
197	default:
198		w1_bits = 0;
199		break;
200	}
201	return w1_bits;
202}
203
204static int thunder_pem_bridge_write(struct pci_bus *bus, unsigned int devfn,
205				    int where, int size, u32 val)
206{
207	struct pci_config_window *cfg = bus->sysdata;
208	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
209	u64 write_val, read_val;
210	u64 where_aligned = where & ~3ull;
211	u32 mask = 0;
212
213
214	if (devfn != 0 || where >= 2048)
215		return PCIBIOS_DEVICE_NOT_FOUND;
216
217	/*
218	 * 32-bit accesses only.  If the write is for a size smaller
219	 * than 32-bits, we must first read the 32-bit value and merge
220	 * in the desired bits and then write the whole 32-bits back
221	 * out.
222	 */
223	switch (size) {
224	case 1:
225		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
226		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
227		read_val >>= 32;
228		mask = ~(0xff << (8 * (where & 3)));
229		read_val &= mask;
230		val = (val & 0xff) << (8 * (where & 3));
231		val |= (u32)read_val;
232		break;
233	case 2:
234		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
235		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
236		read_val >>= 32;
237		mask = ~(0xffff << (8 * (where & 3)));
238		read_val &= mask;
239		val = (val & 0xffff) << (8 * (where & 3));
240		val |= (u32)read_val;
241		break;
242	default:
243		break;
244	}
245
246	/*
247	 * By expanding the write width to 32 bits, we may
248	 * inadvertently hit some W1C bits that were not intended to
249	 * be written.  Calculate the mask that must be applied to the
250	 * data to be written to avoid these cases.
251	 */
252	if (mask) {
253		u32 w1c_bits = thunder_pem_bridge_w1c_bits(where);
254
255		if (w1c_bits) {
256			mask &= w1c_bits;
257			val &= ~mask;
258		}
259	}
260
261	/*
262	 * Some bits must be read-only with value of one.  Since the
263	 * access method allows these to be cleared if a zero is
264	 * written, force them to one before writing.
265	 */
266	val |= thunder_pem_bridge_w1_bits(where_aligned);
267
268	/*
269	 * Low order bits are the config address, the high order 32
270	 * bits are the data to be written.
271	 */
272	write_val = (((u64)val) << 32) | where_aligned;
273	writeq(write_val, pem_pci->pem_reg_base + PEM_CFG_WR);
274	return PCIBIOS_SUCCESSFUL;
275}
276
277static int thunder_pem_config_write(struct pci_bus *bus, unsigned int devfn,
278				    int where, int size, u32 val)
279{
280	struct pci_config_window *cfg = bus->sysdata;
281
282	if (bus->number < cfg->busr.start ||
283	    bus->number > cfg->busr.end)
284		return PCIBIOS_DEVICE_NOT_FOUND;
285	/*
286	 * The first device on the bus is the PEM PCIe bridge.
287	 * Special case its config access.
288	 */
289	if (bus->number == cfg->busr.start)
290		return thunder_pem_bridge_write(bus, devfn, where, size, val);
291
292
293	return pci_generic_config_write(bus, devfn, where, size, val);
294}
295
296static int thunder_pem_init(struct device *dev, struct pci_config_window *cfg,
297			    struct resource *res_pem)
298{
299	struct thunder_pem_pci *pem_pci;
300	resource_size_t bar4_start;
301
302	pem_pci = devm_kzalloc(dev, sizeof(*pem_pci), GFP_KERNEL);
303	if (!pem_pci)
304		return -ENOMEM;
305
306	pem_pci->pem_reg_base = devm_ioremap(dev, res_pem->start, 0x10000);
307	if (!pem_pci->pem_reg_base)
308		return -ENOMEM;
309
310	/*
311	 * The MSI-X BAR for the PEM and AER interrupts is located at
312	 * a fixed offset from the PEM register base.  Generate a
313	 * fragment of the synthesized Enhanced Allocation capability
314	 * structure here for the BAR.
315	 */
316	bar4_start = res_pem->start + 0xf00000;
317	pem_pci->ea_entry[0] = (u32)bar4_start | 2;
318	pem_pci->ea_entry[1] = (u32)(res_pem->end - bar4_start) & ~3u;
319	pem_pci->ea_entry[2] = (u32)(bar4_start >> 32);
320
321	cfg->priv = pem_pci;
322	return 0;
323}
324
325#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
326
327#define PEM_RES_BASE		0x87e0c0000000UL
328#define PEM_NODE_MASK		GENMASK(45, 44)
329#define PEM_INDX_MASK		GENMASK(26, 24)
330#define PEM_MIN_DOM_IN_NODE	4
331#define PEM_MAX_DOM_IN_NODE	10
332
333static void thunder_pem_reserve_range(struct device *dev, int seg,
334				      struct resource *r)
335{
336	resource_size_t start = r->start, end = r->end;
337	struct resource *res;
338	const char *regionid;
339
340	regionid = kasprintf(GFP_KERNEL, "PEM RC:%d", seg);
341	if (!regionid)
342		return;
343
344	res = request_mem_region(start, end - start + 1, regionid);
345	if (res)
346		res->flags &= ~IORESOURCE_BUSY;
347	else
348		kfree(regionid);
349
350	dev_info(dev, "%pR %s reserved\n", r,
351		 res ? "has been" : "could not be");
352}
353
354static void thunder_pem_legacy_fw(struct acpi_pci_root *root,
355				 struct resource *res_pem)
356{
357	int node = acpi_get_node(root->device->handle);
358	int index;
359
360	if (node == NUMA_NO_NODE)
361		node = 0;
362
363	index = root->segment - PEM_MIN_DOM_IN_NODE;
364	index -= node * PEM_MAX_DOM_IN_NODE;
365	res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) |
366					FIELD_PREP(PEM_INDX_MASK, index);
367	res_pem->flags = IORESOURCE_MEM;
368}
369
370static int thunder_pem_acpi_init(struct pci_config_window *cfg)
371{
372	struct device *dev = cfg->parent;
373	struct acpi_device *adev = to_acpi_device(dev);
374	struct acpi_pci_root *root = acpi_driver_data(adev);
375	struct resource *res_pem;
376	int ret;
377
378	res_pem = devm_kzalloc(&adev->dev, sizeof(*res_pem), GFP_KERNEL);
379	if (!res_pem)
380		return -ENOMEM;
381
382	ret = acpi_get_rc_resources(dev, "CAVA02B", root->segment, res_pem);
383
384	/*
385	 * If we fail to gather resources it means that we run with old
386	 * FW where we need to calculate PEM-specific resources manually.
387	 */
388	if (ret) {
389		thunder_pem_legacy_fw(root, res_pem);
390		/*
391		 * Reserve 64K size PEM specific resources. The full 16M range
392		 * size is required for thunder_pem_init() call.
393		 */
394		res_pem->end = res_pem->start + SZ_64K - 1;
395		thunder_pem_reserve_range(dev, root->segment, res_pem);
396		res_pem->end = res_pem->start + SZ_16M - 1;
397
398		/* Reserve PCI configuration space as well. */
399		thunder_pem_reserve_range(dev, root->segment, &cfg->res);
400	}
401
402	return thunder_pem_init(dev, cfg, res_pem);
403}
404
405struct pci_ecam_ops thunder_pem_ecam_ops = {
406	.bus_shift	= 24,
407	.init		= thunder_pem_acpi_init,
408	.pci_ops	= {
409		.map_bus	= pci_ecam_map_bus,
410		.read		= thunder_pem_config_read,
411		.write		= thunder_pem_config_write,
412	}
413};
414
415#endif
416
417#ifdef CONFIG_PCI_HOST_THUNDER_PEM
418
419static int thunder_pem_platform_init(struct pci_config_window *cfg)
420{
421	struct device *dev = cfg->parent;
422	struct platform_device *pdev = to_platform_device(dev);
423	struct resource *res_pem;
424
425	if (!dev->of_node)
426		return -EINVAL;
427
428	/*
429	 * The second register range is the PEM bridge to the PCIe
430	 * bus.  It has a different config access method than those
431	 * devices behind the bridge.
432	 */
433	res_pem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
434	if (!res_pem) {
435		dev_err(dev, "missing \"reg[1]\"property\n");
436		return -EINVAL;
437	}
438
439	return thunder_pem_init(dev, cfg, res_pem);
440}
441
442static struct pci_ecam_ops pci_thunder_pem_ops = {
443	.bus_shift	= 24,
444	.init		= thunder_pem_platform_init,
445	.pci_ops	= {
446		.map_bus	= pci_ecam_map_bus,
447		.read		= thunder_pem_config_read,
448		.write		= thunder_pem_config_write,
449	}
450};
451
452static const struct of_device_id thunder_pem_of_match[] = {
453	{ .compatible = "cavium,pci-host-thunder-pem" },
 
 
 
454	{ },
455};
456
457static int thunder_pem_probe(struct platform_device *pdev)
458{
459	return pci_host_common_probe(pdev, &pci_thunder_pem_ops);
460}
461
462static struct platform_driver thunder_pem_driver = {
463	.driver = {
464		.name = KBUILD_MODNAME,
465		.of_match_table = thunder_pem_of_match,
466		.suppress_bind_attrs = true,
467	},
468	.probe = thunder_pem_probe,
469};
470builtin_platform_driver(thunder_pem_driver);
471
472#endif
473#endif
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2015 - 2016 Cavium, Inc.
  4 */
  5
  6#include <linux/bitfield.h>
  7#include <linux/kernel.h>
  8#include <linux/init.h>
  9#include <linux/pci.h>
 10#include <linux/of_address.h>
 11#include <linux/of_pci.h>
 12#include <linux/pci-acpi.h>
 13#include <linux/pci-ecam.h>
 14#include <linux/platform_device.h>
 15#include "../pci.h"
 16
 17#if defined(CONFIG_PCI_HOST_THUNDER_PEM) || (defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS))
 18
 19#define PEM_CFG_WR 0x28
 20#define PEM_CFG_RD 0x30
 21
 22struct thunder_pem_pci {
 23	u32		ea_entry[3];
 24	void __iomem	*pem_reg_base;
 25};
 26
 27static int thunder_pem_bridge_read(struct pci_bus *bus, unsigned int devfn,
 28				   int where, int size, u32 *val)
 29{
 30	u64 read_val, tmp_val;
 31	struct pci_config_window *cfg = bus->sysdata;
 32	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
 33
 34	if (devfn != 0 || where >= 2048) {
 35		*val = ~0;
 36		return PCIBIOS_DEVICE_NOT_FOUND;
 37	}
 38
 39	/*
 40	 * 32-bit accesses only.  Write the address to the low order
 41	 * bits of PEM_CFG_RD, then trigger the read by reading back.
 42	 * The config data lands in the upper 32-bits of PEM_CFG_RD.
 43	 */
 44	read_val = where & ~3ull;
 45	writeq(read_val, pem_pci->pem_reg_base + PEM_CFG_RD);
 46	read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
 47	read_val >>= 32;
 48
 49	/*
 50	 * The config space contains some garbage, fix it up.  Also
 51	 * synthesize an EA capability for the BAR used by MSI-X.
 52	 */
 53	switch (where & ~3) {
 54	case 0x40:
 55		read_val &= 0xffff00ff;
 56		read_val |= 0x00007000; /* Skip MSI CAP */
 57		break;
 58	case 0x70: /* Express Cap */
 59		/*
 60		 * Change PME interrupt to vector 2 on T88 where it
 61		 * reads as 0, else leave it alone.
 62		 */
 63		if (!(read_val & (0x1f << 25)))
 64			read_val |= (2u << 25);
 65		break;
 66	case 0xb0: /* MSI-X Cap */
 67		/* TableSize=2 or 4, Next Cap is EA */
 68		read_val &= 0xc00000ff;
 69		/*
 70		 * If Express Cap(0x70) raw PME vector reads as 0 we are on
 71		 * T88 and TableSize is reported as 4, else TableSize
 72		 * is 2.
 73		 */
 74		writeq(0x70, pem_pci->pem_reg_base + PEM_CFG_RD);
 75		tmp_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
 76		tmp_val >>= 32;
 77		if (!(tmp_val & (0x1f << 25)))
 78			read_val |= 0x0003bc00;
 79		else
 80			read_val |= 0x0001bc00;
 81		break;
 82	case 0xb4:
 83		/* Table offset=0, BIR=0 */
 84		read_val = 0x00000000;
 85		break;
 86	case 0xb8:
 87		/* BPA offset=0xf0000, BIR=0 */
 88		read_val = 0x000f0000;
 89		break;
 90	case 0xbc:
 91		/* EA, 1 entry, no next Cap */
 92		read_val = 0x00010014;
 93		break;
 94	case 0xc0:
 95		/* DW2 for type-1 */
 96		read_val = 0x00000000;
 97		break;
 98	case 0xc4:
 99		/* Entry BEI=0, PP=0x00, SP=0xff, ES=3 */
100		read_val = 0x80ff0003;
101		break;
102	case 0xc8:
103		read_val = pem_pci->ea_entry[0];
104		break;
105	case 0xcc:
106		read_val = pem_pci->ea_entry[1];
107		break;
108	case 0xd0:
109		read_val = pem_pci->ea_entry[2];
110		break;
111	default:
112		break;
113	}
114	read_val >>= (8 * (where & 3));
115	switch (size) {
116	case 1:
117		read_val &= 0xff;
118		break;
119	case 2:
120		read_val &= 0xffff;
121		break;
122	default:
123		break;
124	}
125	*val = read_val;
126	return PCIBIOS_SUCCESSFUL;
127}
128
129static int thunder_pem_config_read(struct pci_bus *bus, unsigned int devfn,
130				   int where, int size, u32 *val)
131{
132	struct pci_config_window *cfg = bus->sysdata;
133
134	if (bus->number < cfg->busr.start ||
135	    bus->number > cfg->busr.end)
136		return PCIBIOS_DEVICE_NOT_FOUND;
137
138	/*
139	 * The first device on the bus is the PEM PCIe bridge.
140	 * Special case its config access.
141	 */
142	if (bus->number == cfg->busr.start)
143		return thunder_pem_bridge_read(bus, devfn, where, size, val);
144
145	return pci_generic_config_read(bus, devfn, where, size, val);
146}
147
148/*
149 * Some of the w1c_bits below also include read-only or non-writable
150 * reserved bits, this makes the code simpler and is OK as the bits
151 * are not affected by writing zeros to them.
152 */
153static u32 thunder_pem_bridge_w1c_bits(u64 where_aligned)
154{
155	u32 w1c_bits = 0;
156
157	switch (where_aligned) {
158	case 0x04: /* Command/Status */
159	case 0x1c: /* Base and I/O Limit/Secondary Status */
160		w1c_bits = 0xff000000;
161		break;
162	case 0x44: /* Power Management Control and Status */
163		w1c_bits = 0xfffffe00;
164		break;
165	case 0x78: /* Device Control/Device Status */
166	case 0x80: /* Link Control/Link Status */
167	case 0x88: /* Slot Control/Slot Status */
168	case 0x90: /* Root Status */
169	case 0xa0: /* Link Control 2 Registers/Link Status 2 */
170		w1c_bits = 0xffff0000;
171		break;
172	case 0x104: /* Uncorrectable Error Status */
173	case 0x110: /* Correctable Error Status */
174	case 0x130: /* Error Status */
175	case 0x160: /* Link Control 4 */
176		w1c_bits = 0xffffffff;
177		break;
178	default:
179		break;
180	}
181	return w1c_bits;
182}
183
184/* Some bits must be written to one so they appear to be read-only. */
185static u32 thunder_pem_bridge_w1_bits(u64 where_aligned)
186{
187	u32 w1_bits;
188
189	switch (where_aligned) {
190	case 0x1c: /* I/O Base / I/O Limit, Secondary Status */
191		/* Force 32-bit I/O addressing. */
192		w1_bits = 0x0101;
193		break;
194	case 0x24: /* Prefetchable Memory Base / Prefetchable Memory Limit */
195		/* Force 64-bit addressing */
196		w1_bits = 0x00010001;
197		break;
198	default:
199		w1_bits = 0;
200		break;
201	}
202	return w1_bits;
203}
204
205static int thunder_pem_bridge_write(struct pci_bus *bus, unsigned int devfn,
206				    int where, int size, u32 val)
207{
208	struct pci_config_window *cfg = bus->sysdata;
209	struct thunder_pem_pci *pem_pci = (struct thunder_pem_pci *)cfg->priv;
210	u64 write_val, read_val;
211	u64 where_aligned = where & ~3ull;
212	u32 mask = 0;
213
214
215	if (devfn != 0 || where >= 2048)
216		return PCIBIOS_DEVICE_NOT_FOUND;
217
218	/*
219	 * 32-bit accesses only.  If the write is for a size smaller
220	 * than 32-bits, we must first read the 32-bit value and merge
221	 * in the desired bits and then write the whole 32-bits back
222	 * out.
223	 */
224	switch (size) {
225	case 1:
226		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
227		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
228		read_val >>= 32;
229		mask = ~(0xff << (8 * (where & 3)));
230		read_val &= mask;
231		val = (val & 0xff) << (8 * (where & 3));
232		val |= (u32)read_val;
233		break;
234	case 2:
235		writeq(where_aligned, pem_pci->pem_reg_base + PEM_CFG_RD);
236		read_val = readq(pem_pci->pem_reg_base + PEM_CFG_RD);
237		read_val >>= 32;
238		mask = ~(0xffff << (8 * (where & 3)));
239		read_val &= mask;
240		val = (val & 0xffff) << (8 * (where & 3));
241		val |= (u32)read_val;
242		break;
243	default:
244		break;
245	}
246
247	/*
248	 * By expanding the write width to 32 bits, we may
249	 * inadvertently hit some W1C bits that were not intended to
250	 * be written.  Calculate the mask that must be applied to the
251	 * data to be written to avoid these cases.
252	 */
253	if (mask) {
254		u32 w1c_bits = thunder_pem_bridge_w1c_bits(where);
255
256		if (w1c_bits) {
257			mask &= w1c_bits;
258			val &= ~mask;
259		}
260	}
261
262	/*
263	 * Some bits must be read-only with value of one.  Since the
264	 * access method allows these to be cleared if a zero is
265	 * written, force them to one before writing.
266	 */
267	val |= thunder_pem_bridge_w1_bits(where_aligned);
268
269	/*
270	 * Low order bits are the config address, the high order 32
271	 * bits are the data to be written.
272	 */
273	write_val = (((u64)val) << 32) | where_aligned;
274	writeq(write_val, pem_pci->pem_reg_base + PEM_CFG_WR);
275	return PCIBIOS_SUCCESSFUL;
276}
277
278static int thunder_pem_config_write(struct pci_bus *bus, unsigned int devfn,
279				    int where, int size, u32 val)
280{
281	struct pci_config_window *cfg = bus->sysdata;
282
283	if (bus->number < cfg->busr.start ||
284	    bus->number > cfg->busr.end)
285		return PCIBIOS_DEVICE_NOT_FOUND;
286	/*
287	 * The first device on the bus is the PEM PCIe bridge.
288	 * Special case its config access.
289	 */
290	if (bus->number == cfg->busr.start)
291		return thunder_pem_bridge_write(bus, devfn, where, size, val);
292
293
294	return pci_generic_config_write(bus, devfn, where, size, val);
295}
296
297static int thunder_pem_init(struct device *dev, struct pci_config_window *cfg,
298			    struct resource *res_pem)
299{
300	struct thunder_pem_pci *pem_pci;
301	resource_size_t bar4_start;
302
303	pem_pci = devm_kzalloc(dev, sizeof(*pem_pci), GFP_KERNEL);
304	if (!pem_pci)
305		return -ENOMEM;
306
307	pem_pci->pem_reg_base = devm_ioremap(dev, res_pem->start, 0x10000);
308	if (!pem_pci->pem_reg_base)
309		return -ENOMEM;
310
311	/*
312	 * The MSI-X BAR for the PEM and AER interrupts is located at
313	 * a fixed offset from the PEM register base.  Generate a
314	 * fragment of the synthesized Enhanced Allocation capability
315	 * structure here for the BAR.
316	 */
317	bar4_start = res_pem->start + 0xf00000;
318	pem_pci->ea_entry[0] = (u32)bar4_start | 2;
319	pem_pci->ea_entry[1] = (u32)(res_pem->end - bar4_start) & ~3u;
320	pem_pci->ea_entry[2] = (u32)(bar4_start >> 32);
321
322	cfg->priv = pem_pci;
323	return 0;
324}
325
326#if defined(CONFIG_ACPI) && defined(CONFIG_PCI_QUIRKS)
327
328#define PEM_RES_BASE		0x87e0c0000000UL
329#define PEM_NODE_MASK		GENMASK(45, 44)
330#define PEM_INDX_MASK		GENMASK(26, 24)
331#define PEM_MIN_DOM_IN_NODE	4
332#define PEM_MAX_DOM_IN_NODE	10
333
334static void thunder_pem_reserve_range(struct device *dev, int seg,
335				      struct resource *r)
336{
337	resource_size_t start = r->start, end = r->end;
338	struct resource *res;
339	const char *regionid;
340
341	regionid = kasprintf(GFP_KERNEL, "PEM RC:%d", seg);
342	if (!regionid)
343		return;
344
345	res = request_mem_region(start, end - start + 1, regionid);
346	if (res)
347		res->flags &= ~IORESOURCE_BUSY;
348	else
349		kfree(regionid);
350
351	dev_info(dev, "%pR %s reserved\n", r,
352		 res ? "has been" : "could not be");
353}
354
355static void thunder_pem_legacy_fw(struct acpi_pci_root *root,
356				 struct resource *res_pem)
357{
358	int node = acpi_get_node(root->device->handle);
359	int index;
360
361	if (node == NUMA_NO_NODE)
362		node = 0;
363
364	index = root->segment - PEM_MIN_DOM_IN_NODE;
365	index -= node * PEM_MAX_DOM_IN_NODE;
366	res_pem->start = PEM_RES_BASE | FIELD_PREP(PEM_NODE_MASK, node) |
367					FIELD_PREP(PEM_INDX_MASK, index);
368	res_pem->flags = IORESOURCE_MEM;
369}
370
371static int thunder_pem_acpi_init(struct pci_config_window *cfg)
372{
373	struct device *dev = cfg->parent;
374	struct acpi_device *adev = to_acpi_device(dev);
375	struct acpi_pci_root *root = acpi_driver_data(adev);
376	struct resource *res_pem;
377	int ret;
378
379	res_pem = devm_kzalloc(&adev->dev, sizeof(*res_pem), GFP_KERNEL);
380	if (!res_pem)
381		return -ENOMEM;
382
383	ret = acpi_get_rc_resources(dev, "CAVA02B", root->segment, res_pem);
384
385	/*
386	 * If we fail to gather resources it means that we run with old
387	 * FW where we need to calculate PEM-specific resources manually.
388	 */
389	if (ret) {
390		thunder_pem_legacy_fw(root, res_pem);
391		/*
392		 * Reserve 64K size PEM specific resources. The full 16M range
393		 * size is required for thunder_pem_init() call.
394		 */
395		res_pem->end = res_pem->start + SZ_64K - 1;
396		thunder_pem_reserve_range(dev, root->segment, res_pem);
397		res_pem->end = res_pem->start + SZ_16M - 1;
398
399		/* Reserve PCI configuration space as well. */
400		thunder_pem_reserve_range(dev, root->segment, &cfg->res);
401	}
402
403	return thunder_pem_init(dev, cfg, res_pem);
404}
405
406const struct pci_ecam_ops thunder_pem_ecam_ops = {
407	.bus_shift	= 24,
408	.init		= thunder_pem_acpi_init,
409	.pci_ops	= {
410		.map_bus	= pci_ecam_map_bus,
411		.read		= thunder_pem_config_read,
412		.write		= thunder_pem_config_write,
413	}
414};
415
416#endif
417
418#ifdef CONFIG_PCI_HOST_THUNDER_PEM
419
420static int thunder_pem_platform_init(struct pci_config_window *cfg)
421{
422	struct device *dev = cfg->parent;
423	struct platform_device *pdev = to_platform_device(dev);
424	struct resource *res_pem;
425
426	if (!dev->of_node)
427		return -EINVAL;
428
429	/*
430	 * The second register range is the PEM bridge to the PCIe
431	 * bus.  It has a different config access method than those
432	 * devices behind the bridge.
433	 */
434	res_pem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
435	if (!res_pem) {
436		dev_err(dev, "missing \"reg[1]\"property\n");
437		return -EINVAL;
438	}
439
440	return thunder_pem_init(dev, cfg, res_pem);
441}
442
443static const struct pci_ecam_ops pci_thunder_pem_ops = {
444	.bus_shift	= 24,
445	.init		= thunder_pem_platform_init,
446	.pci_ops	= {
447		.map_bus	= pci_ecam_map_bus,
448		.read		= thunder_pem_config_read,
449		.write		= thunder_pem_config_write,
450	}
451};
452
453static const struct of_device_id thunder_pem_of_match[] = {
454	{
455		.compatible = "cavium,pci-host-thunder-pem",
456		.data = &pci_thunder_pem_ops,
457	},
458	{ },
459};
460
 
 
 
 
 
461static struct platform_driver thunder_pem_driver = {
462	.driver = {
463		.name = KBUILD_MODNAME,
464		.of_match_table = thunder_pem_of_match,
465		.suppress_bind_attrs = true,
466	},
467	.probe = pci_host_common_probe,
468};
469builtin_platform_driver(thunder_pem_driver);
470
471#endif
472#endif