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v5.14.15
  1// SPDX-License-Identifier: GPL-2.0
  2#define KMSG_COMPONENT "zpci"
  3#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  4
  5#include <linux/kernel.h>
  6#include <linux/irq.h>
  7#include <linux/kernel_stat.h>
  8#include <linux/pci.h>
  9#include <linux/msi.h>
 10#include <linux/smp.h>
 11
 12#include <asm/isc.h>
 13#include <asm/airq.h>
 14
 15static enum {FLOATING, DIRECTED} irq_delivery;
 16
 17#define	SIC_IRQ_MODE_ALL		0
 18#define	SIC_IRQ_MODE_SINGLE		1
 19#define	SIC_IRQ_MODE_DIRECT		4
 20#define	SIC_IRQ_MODE_D_ALL		16
 21#define	SIC_IRQ_MODE_D_SINGLE		17
 22#define	SIC_IRQ_MODE_SET_CPU		18
 23
 24/*
 25 * summary bit vector
 26 * FLOATING - summary bit per function
 27 * DIRECTED - summary bit per cpu (only used in fallback path)
 28 */
 29static struct airq_iv *zpci_sbv;
 30
 31/*
 32 * interrupt bit vectors
 33 * FLOATING - interrupt bit vector per function
 34 * DIRECTED - interrupt bit vector per cpu
 35 */
 36static struct airq_iv **zpci_ibv;
 37
 38/* Modify PCI: Register floating adapter interruptions */
 39static int zpci_set_airq(struct zpci_dev *zdev)
 40{
 41	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT);
 42	struct zpci_fib fib = {0};
 43	u8 status;
 44
 45	fib.fmt0.isc = PCI_ISC;
 46	fib.fmt0.sum = 1;	/* enable summary notifications */
 47	fib.fmt0.noi = airq_iv_end(zdev->aibv);
 48	fib.fmt0.aibv = (unsigned long) zdev->aibv->vector;
 49	fib.fmt0.aibvo = 0;	/* each zdev has its own interrupt vector */
 50	fib.fmt0.aisb = (unsigned long) zpci_sbv->vector + (zdev->aisb/64)*8;
 51	fib.fmt0.aisbo = zdev->aisb & 63;
 52
 53	return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
 54}
 55
 56/* Modify PCI: Unregister floating adapter interruptions */
 57static int zpci_clear_airq(struct zpci_dev *zdev)
 58{
 59	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT);
 60	struct zpci_fib fib = {0};
 61	u8 cc, status;
 62
 63	cc = zpci_mod_fc(req, &fib, &status);
 64	if (cc == 3 || (cc == 1 && status == 24))
 65		/* Function already gone or IRQs already deregistered. */
 66		cc = 0;
 67
 68	return cc ? -EIO : 0;
 69}
 70
 71/* Modify PCI: Register CPU directed interruptions */
 72static int zpci_set_directed_irq(struct zpci_dev *zdev)
 73{
 74	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT_D);
 75	struct zpci_fib fib = {0};
 76	u8 status;
 77
 78	fib.fmt = 1;
 79	fib.fmt1.noi = zdev->msi_nr_irqs;
 80	fib.fmt1.dibvo = zdev->msi_first_bit;
 81
 82	return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
 83}
 84
 85/* Modify PCI: Unregister CPU directed interruptions */
 86static int zpci_clear_directed_irq(struct zpci_dev *zdev)
 87{
 88	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT_D);
 89	struct zpci_fib fib = {0};
 90	u8 cc, status;
 91
 92	fib.fmt = 1;
 93	cc = zpci_mod_fc(req, &fib, &status);
 94	if (cc == 3 || (cc == 1 && status == 24))
 95		/* Function already gone or IRQs already deregistered. */
 96		cc = 0;
 97
 98	return cc ? -EIO : 0;
 99}
100
101/* Register adapter interruptions */
102int zpci_set_irq(struct zpci_dev *zdev)
103{
104	int rc;
105
106	if (irq_delivery == DIRECTED)
107		rc = zpci_set_directed_irq(zdev);
108	else
109		rc = zpci_set_airq(zdev);
110
111	if (!rc)
112		zdev->irqs_registered = 1;
113
114	return rc;
115}
116
117/* Clear adapter interruptions */
118int zpci_clear_irq(struct zpci_dev *zdev)
119{
120	int rc;
121
122	if (irq_delivery == DIRECTED)
123		rc = zpci_clear_directed_irq(zdev);
124	else
125		rc = zpci_clear_airq(zdev);
126
127	if (!rc)
128		zdev->irqs_registered = 0;
129
130	return rc;
131}
132
133static int zpci_set_irq_affinity(struct irq_data *data, const struct cpumask *dest,
134				 bool force)
135{
136	struct msi_desc *entry = irq_get_msi_desc(data->irq);
137	struct msi_msg msg = entry->msg;
138	int cpu_addr = smp_cpu_get_cpu_address(cpumask_first(dest));
139
140	msg.address_lo &= 0xff0000ff;
141	msg.address_lo |= (cpu_addr << 8);
142	pci_write_msi_msg(data->irq, &msg);
143
144	return IRQ_SET_MASK_OK;
145}
146
147static struct irq_chip zpci_irq_chip = {
148	.name = "PCI-MSI",
149	.irq_unmask = pci_msi_unmask_irq,
150	.irq_mask = pci_msi_mask_irq,
151};
152
153static void zpci_handle_cpu_local_irq(bool rescan)
154{
155	struct airq_iv *dibv = zpci_ibv[smp_processor_id()];
156	unsigned long bit;
157	int irqs_on = 0;
158
159	for (bit = 0;;) {
160		/* Scan the directed IRQ bit vector */
161		bit = airq_iv_scan(dibv, bit, airq_iv_end(dibv));
162		if (bit == -1UL) {
163			if (!rescan || irqs_on++)
164				/* End of second scan with interrupts on. */
165				break;
166			/* First scan complete, reenable interrupts. */
167			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC))
168				break;
169			bit = 0;
170			continue;
171		}
172		inc_irq_stat(IRQIO_MSI);
173		generic_handle_irq(airq_iv_get_data(dibv, bit));
174	}
175}
176
177struct cpu_irq_data {
178	call_single_data_t csd;
179	atomic_t scheduled;
180};
181static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_irq_data, irq_data);
182
183static void zpci_handle_remote_irq(void *data)
184{
185	atomic_t *scheduled = data;
186
187	do {
188		zpci_handle_cpu_local_irq(false);
189	} while (atomic_dec_return(scheduled));
190}
191
192static void zpci_handle_fallback_irq(void)
193{
194	struct cpu_irq_data *cpu_data;
195	unsigned long cpu;
196	int irqs_on = 0;
197
198	for (cpu = 0;;) {
199		cpu = airq_iv_scan(zpci_sbv, cpu, airq_iv_end(zpci_sbv));
200		if (cpu == -1UL) {
201			if (irqs_on++)
202				/* End of second scan with interrupts on. */
203				break;
204			/* First scan complete, reenable interrupts. */
205			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC))
206				break;
207			cpu = 0;
208			continue;
209		}
210		cpu_data = &per_cpu(irq_data, cpu);
211		if (atomic_inc_return(&cpu_data->scheduled) > 1)
212			continue;
213
214		INIT_CSD(&cpu_data->csd, zpci_handle_remote_irq, &cpu_data->scheduled);
 
 
215		smp_call_function_single_async(cpu, &cpu_data->csd);
216	}
217}
218
219static void zpci_directed_irq_handler(struct airq_struct *airq, bool floating)
220{
221	if (floating) {
222		inc_irq_stat(IRQIO_PCF);
223		zpci_handle_fallback_irq();
224	} else {
225		inc_irq_stat(IRQIO_PCD);
226		zpci_handle_cpu_local_irq(true);
227	}
228}
229
230static void zpci_floating_irq_handler(struct airq_struct *airq, bool floating)
231{
232	unsigned long si, ai;
233	struct airq_iv *aibv;
234	int irqs_on = 0;
235
236	inc_irq_stat(IRQIO_PCF);
237	for (si = 0;;) {
238		/* Scan adapter summary indicator bit vector */
239		si = airq_iv_scan(zpci_sbv, si, airq_iv_end(zpci_sbv));
240		if (si == -1UL) {
241			if (irqs_on++)
242				/* End of second scan with interrupts on. */
243				break;
244			/* First scan complete, reenable interrupts. */
245			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC))
246				break;
247			si = 0;
248			continue;
249		}
250
251		/* Scan the adapter interrupt vector for this device. */
252		aibv = zpci_ibv[si];
253		for (ai = 0;;) {
254			ai = airq_iv_scan(aibv, ai, airq_iv_end(aibv));
255			if (ai == -1UL)
256				break;
257			inc_irq_stat(IRQIO_MSI);
258			airq_iv_lock(aibv, ai);
259			generic_handle_irq(airq_iv_get_data(aibv, ai));
260			airq_iv_unlock(aibv, ai);
261		}
262	}
263}
264
265int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
266{
267	struct zpci_dev *zdev = to_zpci(pdev);
268	unsigned int hwirq, msi_vecs, cpu;
269	unsigned long bit;
270	struct msi_desc *msi;
271	struct msi_msg msg;
272	int cpu_addr;
273	int rc, irq;
274
275	zdev->aisb = -1UL;
276	zdev->msi_first_bit = -1U;
277	if (type == PCI_CAP_ID_MSI && nvec > 1)
278		return 1;
279	msi_vecs = min_t(unsigned int, nvec, zdev->max_msi);
280
281	if (irq_delivery == DIRECTED) {
282		/* Allocate cpu vector bits */
283		bit = airq_iv_alloc(zpci_ibv[0], msi_vecs);
284		if (bit == -1UL)
285			return -EIO;
286	} else {
287		/* Allocate adapter summary indicator bit */
288		bit = airq_iv_alloc_bit(zpci_sbv);
289		if (bit == -1UL)
290			return -EIO;
291		zdev->aisb = bit;
292
293		/* Create adapter interrupt vector */
294		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK);
295		if (!zdev->aibv)
296			return -ENOMEM;
297
298		/* Wire up shortcut pointer */
299		zpci_ibv[bit] = zdev->aibv;
300		/* Each function has its own interrupt vector */
301		bit = 0;
302	}
303
304	/* Request MSI interrupts */
305	hwirq = bit;
306	for_each_pci_msi_entry(msi, pdev) {
307		rc = -EIO;
308		if (hwirq - bit >= msi_vecs)
309			break;
310		irq = __irq_alloc_descs(-1, 0, 1, 0, THIS_MODULE,
311				(irq_delivery == DIRECTED) ?
312				msi->affinity : NULL);
313		if (irq < 0)
314			return -ENOMEM;
315		rc = irq_set_msi_desc(irq, msi);
316		if (rc)
317			return rc;
318		irq_set_chip_and_handler(irq, &zpci_irq_chip,
319					 handle_percpu_irq);
320		msg.data = hwirq - bit;
321		if (irq_delivery == DIRECTED) {
322			if (msi->affinity)
323				cpu = cpumask_first(&msi->affinity->mask);
324			else
325				cpu = 0;
326			cpu_addr = smp_cpu_get_cpu_address(cpu);
327
328			msg.address_lo = zdev->msi_addr & 0xff0000ff;
329			msg.address_lo |= (cpu_addr << 8);
330
331			for_each_possible_cpu(cpu) {
332				airq_iv_set_data(zpci_ibv[cpu], hwirq, irq);
333			}
334		} else {
335			msg.address_lo = zdev->msi_addr & 0xffffffff;
336			airq_iv_set_data(zdev->aibv, hwirq, irq);
337		}
338		msg.address_hi = zdev->msi_addr >> 32;
339		pci_write_msi_msg(irq, &msg);
340		hwirq++;
341	}
342
343	zdev->msi_first_bit = bit;
344	zdev->msi_nr_irqs = msi_vecs;
345
346	rc = zpci_set_irq(zdev);
 
 
 
347	if (rc)
348		return rc;
349
350	return (msi_vecs == nvec) ? 0 : msi_vecs;
351}
352
353void arch_teardown_msi_irqs(struct pci_dev *pdev)
354{
355	struct zpci_dev *zdev = to_zpci(pdev);
356	struct msi_desc *msi;
357	int rc;
358
359	/* Disable interrupts */
360	rc = zpci_clear_irq(zdev);
 
 
 
361	if (rc)
362		return;
363
364	/* Release MSI interrupts */
365	for_each_pci_msi_entry(msi, pdev) {
366		if (!msi->irq)
367			continue;
368		if (msi->msi_attrib.is_msix)
369			__pci_msix_desc_mask_irq(msi, 1);
370		else
371			__pci_msi_desc_mask_irq(msi, 1, 1);
372		irq_set_msi_desc(msi->irq, NULL);
373		irq_free_desc(msi->irq);
374		msi->msg.address_lo = 0;
375		msi->msg.address_hi = 0;
376		msi->msg.data = 0;
377		msi->irq = 0;
378	}
379
380	if (zdev->aisb != -1UL) {
381		zpci_ibv[zdev->aisb] = NULL;
382		airq_iv_free_bit(zpci_sbv, zdev->aisb);
383		zdev->aisb = -1UL;
384	}
385	if (zdev->aibv) {
386		airq_iv_release(zdev->aibv);
387		zdev->aibv = NULL;
388	}
389
390	if ((irq_delivery == DIRECTED) && zdev->msi_first_bit != -1U)
391		airq_iv_free(zpci_ibv[0], zdev->msi_first_bit, zdev->msi_nr_irqs);
392}
393
394static struct airq_struct zpci_airq = {
395	.handler = zpci_floating_irq_handler,
396	.isc = PCI_ISC,
397};
398
399static void __init cpu_enable_directed_irq(void *unused)
400{
401	union zpci_sic_iib iib = {{0}};
402
403	iib.cdiib.dibv_addr = (u64) zpci_ibv[smp_processor_id()]->vector;
404
405	__zpci_set_irq_ctrl(SIC_IRQ_MODE_SET_CPU, 0, &iib);
406	zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC);
407}
408
409static int __init zpci_directed_irq_init(void)
410{
411	union zpci_sic_iib iib = {{0}};
412	unsigned int cpu;
413
414	zpci_sbv = airq_iv_create(num_possible_cpus(), 0);
415	if (!zpci_sbv)
416		return -ENOMEM;
417
418	iib.diib.isc = PCI_ISC;
419	iib.diib.nr_cpus = num_possible_cpus();
420	iib.diib.disb_addr = (u64) zpci_sbv->vector;
421	__zpci_set_irq_ctrl(SIC_IRQ_MODE_DIRECT, 0, &iib);
422
423	zpci_ibv = kcalloc(num_possible_cpus(), sizeof(*zpci_ibv),
424			   GFP_KERNEL);
425	if (!zpci_ibv)
426		return -ENOMEM;
427
428	for_each_possible_cpu(cpu) {
429		/*
430		 * Per CPU IRQ vectors look the same but bit-allocation
431		 * is only done on the first vector.
432		 */
433		zpci_ibv[cpu] = airq_iv_create(cache_line_size() * BITS_PER_BYTE,
434					       AIRQ_IV_DATA |
435					       AIRQ_IV_CACHELINE |
436					       (!cpu ? AIRQ_IV_ALLOC : 0));
437		if (!zpci_ibv[cpu])
438			return -ENOMEM;
439	}
440	on_each_cpu(cpu_enable_directed_irq, NULL, 1);
441
442	zpci_irq_chip.irq_set_affinity = zpci_set_irq_affinity;
443
444	return 0;
445}
446
447static int __init zpci_floating_irq_init(void)
448{
449	zpci_ibv = kcalloc(ZPCI_NR_DEVICES, sizeof(*zpci_ibv), GFP_KERNEL);
450	if (!zpci_ibv)
451		return -ENOMEM;
452
453	zpci_sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC);
454	if (!zpci_sbv)
455		goto out_free;
456
457	return 0;
458
459out_free:
460	kfree(zpci_ibv);
461	return -ENOMEM;
462}
463
464int __init zpci_irq_init(void)
465{
466	int rc;
467
468	irq_delivery = sclp.has_dirq ? DIRECTED : FLOATING;
469	if (s390_pci_force_floating)
470		irq_delivery = FLOATING;
471
472	if (irq_delivery == DIRECTED)
473		zpci_airq.handler = zpci_directed_irq_handler;
474
475	rc = register_adapter_interrupt(&zpci_airq);
476	if (rc)
477		goto out;
478	/* Set summary to 1 to be called every time for the ISC. */
479	*zpci_airq.lsi_ptr = 1;
480
481	switch (irq_delivery) {
482	case FLOATING:
483		rc = zpci_floating_irq_init();
484		break;
485	case DIRECTED:
486		rc = zpci_directed_irq_init();
487		break;
488	}
489
490	if (rc)
491		goto out_airq;
492
493	/*
494	 * Enable floating IRQs (with suppression after one IRQ). When using
495	 * directed IRQs this enables the fallback path.
496	 */
497	zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC);
498
499	return 0;
500out_airq:
501	unregister_adapter_interrupt(&zpci_airq);
502out:
503	return rc;
504}
505
506void __init zpci_irq_exit(void)
507{
508	unsigned int cpu;
509
510	if (irq_delivery == DIRECTED) {
511		for_each_possible_cpu(cpu) {
512			airq_iv_release(zpci_ibv[cpu]);
513		}
514	}
515	kfree(zpci_ibv);
516	if (zpci_sbv)
517		airq_iv_release(zpci_sbv);
518	unregister_adapter_interrupt(&zpci_airq);
519}
v5.9
  1// SPDX-License-Identifier: GPL-2.0
  2#define KMSG_COMPONENT "zpci"
  3#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  4
  5#include <linux/kernel.h>
  6#include <linux/irq.h>
  7#include <linux/kernel_stat.h>
  8#include <linux/pci.h>
  9#include <linux/msi.h>
 10#include <linux/smp.h>
 11
 12#include <asm/isc.h>
 13#include <asm/airq.h>
 14
 15static enum {FLOATING, DIRECTED} irq_delivery;
 16
 17#define	SIC_IRQ_MODE_ALL		0
 18#define	SIC_IRQ_MODE_SINGLE		1
 19#define	SIC_IRQ_MODE_DIRECT		4
 20#define	SIC_IRQ_MODE_D_ALL		16
 21#define	SIC_IRQ_MODE_D_SINGLE		17
 22#define	SIC_IRQ_MODE_SET_CPU		18
 23
 24/*
 25 * summary bit vector
 26 * FLOATING - summary bit per function
 27 * DIRECTED - summary bit per cpu (only used in fallback path)
 28 */
 29static struct airq_iv *zpci_sbv;
 30
 31/*
 32 * interrupt bit vectors
 33 * FLOATING - interrupt bit vector per function
 34 * DIRECTED - interrupt bit vector per cpu
 35 */
 36static struct airq_iv **zpci_ibv;
 37
 38/* Modify PCI: Register adapter interruptions */
 39static int zpci_set_airq(struct zpci_dev *zdev)
 40{
 41	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT);
 42	struct zpci_fib fib = {0};
 43	u8 status;
 44
 45	fib.fmt0.isc = PCI_ISC;
 46	fib.fmt0.sum = 1;	/* enable summary notifications */
 47	fib.fmt0.noi = airq_iv_end(zdev->aibv);
 48	fib.fmt0.aibv = (unsigned long) zdev->aibv->vector;
 49	fib.fmt0.aibvo = 0;	/* each zdev has its own interrupt vector */
 50	fib.fmt0.aisb = (unsigned long) zpci_sbv->vector + (zdev->aisb/64)*8;
 51	fib.fmt0.aisbo = zdev->aisb & 63;
 52
 53	return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
 54}
 55
 56/* Modify PCI: Unregister adapter interruptions */
 57static int zpci_clear_airq(struct zpci_dev *zdev)
 58{
 59	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT);
 60	struct zpci_fib fib = {0};
 61	u8 cc, status;
 62
 63	cc = zpci_mod_fc(req, &fib, &status);
 64	if (cc == 3 || (cc == 1 && status == 24))
 65		/* Function already gone or IRQs already deregistered. */
 66		cc = 0;
 67
 68	return cc ? -EIO : 0;
 69}
 70
 71/* Modify PCI: Register CPU directed interruptions */
 72static int zpci_set_directed_irq(struct zpci_dev *zdev)
 73{
 74	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT_D);
 75	struct zpci_fib fib = {0};
 76	u8 status;
 77
 78	fib.fmt = 1;
 79	fib.fmt1.noi = zdev->msi_nr_irqs;
 80	fib.fmt1.dibvo = zdev->msi_first_bit;
 81
 82	return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
 83}
 84
 85/* Modify PCI: Unregister CPU directed interruptions */
 86static int zpci_clear_directed_irq(struct zpci_dev *zdev)
 87{
 88	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_DEREG_INT_D);
 89	struct zpci_fib fib = {0};
 90	u8 cc, status;
 91
 92	fib.fmt = 1;
 93	cc = zpci_mod_fc(req, &fib, &status);
 94	if (cc == 3 || (cc == 1 && status == 24))
 95		/* Function already gone or IRQs already deregistered. */
 96		cc = 0;
 97
 98	return cc ? -EIO : 0;
 99}
100
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
101static int zpci_set_irq_affinity(struct irq_data *data, const struct cpumask *dest,
102				 bool force)
103{
104	struct msi_desc *entry = irq_get_msi_desc(data->irq);
105	struct msi_msg msg = entry->msg;
 
106
107	msg.address_lo &= 0xff0000ff;
108	msg.address_lo |= (cpumask_first(dest) << 8);
109	pci_write_msi_msg(data->irq, &msg);
110
111	return IRQ_SET_MASK_OK;
112}
113
114static struct irq_chip zpci_irq_chip = {
115	.name = "PCI-MSI",
116	.irq_unmask = pci_msi_unmask_irq,
117	.irq_mask = pci_msi_mask_irq,
118};
119
120static void zpci_handle_cpu_local_irq(bool rescan)
121{
122	struct airq_iv *dibv = zpci_ibv[smp_processor_id()];
123	unsigned long bit;
124	int irqs_on = 0;
125
126	for (bit = 0;;) {
127		/* Scan the directed IRQ bit vector */
128		bit = airq_iv_scan(dibv, bit, airq_iv_end(dibv));
129		if (bit == -1UL) {
130			if (!rescan || irqs_on++)
131				/* End of second scan with interrupts on. */
132				break;
133			/* First scan complete, reenable interrupts. */
134			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC))
135				break;
136			bit = 0;
137			continue;
138		}
139		inc_irq_stat(IRQIO_MSI);
140		generic_handle_irq(airq_iv_get_data(dibv, bit));
141	}
142}
143
144struct cpu_irq_data {
145	call_single_data_t csd;
146	atomic_t scheduled;
147};
148static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_irq_data, irq_data);
149
150static void zpci_handle_remote_irq(void *data)
151{
152	atomic_t *scheduled = data;
153
154	do {
155		zpci_handle_cpu_local_irq(false);
156	} while (atomic_dec_return(scheduled));
157}
158
159static void zpci_handle_fallback_irq(void)
160{
161	struct cpu_irq_data *cpu_data;
162	unsigned long cpu;
163	int irqs_on = 0;
164
165	for (cpu = 0;;) {
166		cpu = airq_iv_scan(zpci_sbv, cpu, airq_iv_end(zpci_sbv));
167		if (cpu == -1UL) {
168			if (irqs_on++)
169				/* End of second scan with interrupts on. */
170				break;
171			/* First scan complete, reenable interrupts. */
172			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC))
173				break;
174			cpu = 0;
175			continue;
176		}
177		cpu_data = &per_cpu(irq_data, cpu);
178		if (atomic_inc_return(&cpu_data->scheduled) > 1)
179			continue;
180
181		cpu_data->csd.func = zpci_handle_remote_irq;
182		cpu_data->csd.info = &cpu_data->scheduled;
183		cpu_data->csd.flags = 0;
184		smp_call_function_single_async(cpu, &cpu_data->csd);
185	}
186}
187
188static void zpci_directed_irq_handler(struct airq_struct *airq, bool floating)
189{
190	if (floating) {
191		inc_irq_stat(IRQIO_PCF);
192		zpci_handle_fallback_irq();
193	} else {
194		inc_irq_stat(IRQIO_PCD);
195		zpci_handle_cpu_local_irq(true);
196	}
197}
198
199static void zpci_floating_irq_handler(struct airq_struct *airq, bool floating)
200{
201	unsigned long si, ai;
202	struct airq_iv *aibv;
203	int irqs_on = 0;
204
205	inc_irq_stat(IRQIO_PCF);
206	for (si = 0;;) {
207		/* Scan adapter summary indicator bit vector */
208		si = airq_iv_scan(zpci_sbv, si, airq_iv_end(zpci_sbv));
209		if (si == -1UL) {
210			if (irqs_on++)
211				/* End of second scan with interrupts on. */
212				break;
213			/* First scan complete, reenable interrupts. */
214			if (zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC))
215				break;
216			si = 0;
217			continue;
218		}
219
220		/* Scan the adapter interrupt vector for this device. */
221		aibv = zpci_ibv[si];
222		for (ai = 0;;) {
223			ai = airq_iv_scan(aibv, ai, airq_iv_end(aibv));
224			if (ai == -1UL)
225				break;
226			inc_irq_stat(IRQIO_MSI);
227			airq_iv_lock(aibv, ai);
228			generic_handle_irq(airq_iv_get_data(aibv, ai));
229			airq_iv_unlock(aibv, ai);
230		}
231	}
232}
233
234int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
235{
236	struct zpci_dev *zdev = to_zpci(pdev);
237	unsigned int hwirq, msi_vecs, cpu;
238	unsigned long bit;
239	struct msi_desc *msi;
240	struct msi_msg msg;
 
241	int rc, irq;
242
243	zdev->aisb = -1UL;
244	zdev->msi_first_bit = -1U;
245	if (type == PCI_CAP_ID_MSI && nvec > 1)
246		return 1;
247	msi_vecs = min_t(unsigned int, nvec, zdev->max_msi);
248
249	if (irq_delivery == DIRECTED) {
250		/* Allocate cpu vector bits */
251		bit = airq_iv_alloc(zpci_ibv[0], msi_vecs);
252		if (bit == -1UL)
253			return -EIO;
254	} else {
255		/* Allocate adapter summary indicator bit */
256		bit = airq_iv_alloc_bit(zpci_sbv);
257		if (bit == -1UL)
258			return -EIO;
259		zdev->aisb = bit;
260
261		/* Create adapter interrupt vector */
262		zdev->aibv = airq_iv_create(msi_vecs, AIRQ_IV_DATA | AIRQ_IV_BITLOCK);
263		if (!zdev->aibv)
264			return -ENOMEM;
265
266		/* Wire up shortcut pointer */
267		zpci_ibv[bit] = zdev->aibv;
268		/* Each function has its own interrupt vector */
269		bit = 0;
270	}
271
272	/* Request MSI interrupts */
273	hwirq = bit;
274	for_each_pci_msi_entry(msi, pdev) {
275		rc = -EIO;
276		if (hwirq - bit >= msi_vecs)
277			break;
278		irq = __irq_alloc_descs(-1, 0, 1, 0, THIS_MODULE,
279				(irq_delivery == DIRECTED) ?
280				msi->affinity : NULL);
281		if (irq < 0)
282			return -ENOMEM;
283		rc = irq_set_msi_desc(irq, msi);
284		if (rc)
285			return rc;
286		irq_set_chip_and_handler(irq, &zpci_irq_chip,
287					 handle_percpu_irq);
288		msg.data = hwirq - bit;
289		if (irq_delivery == DIRECTED) {
 
 
 
 
 
 
290			msg.address_lo = zdev->msi_addr & 0xff0000ff;
291			msg.address_lo |= msi->affinity ?
292				(cpumask_first(&msi->affinity->mask) << 8) : 0;
293			for_each_possible_cpu(cpu) {
294				airq_iv_set_data(zpci_ibv[cpu], hwirq, irq);
295			}
296		} else {
297			msg.address_lo = zdev->msi_addr & 0xffffffff;
298			airq_iv_set_data(zdev->aibv, hwirq, irq);
299		}
300		msg.address_hi = zdev->msi_addr >> 32;
301		pci_write_msi_msg(irq, &msg);
302		hwirq++;
303	}
304
305	zdev->msi_first_bit = bit;
306	zdev->msi_nr_irqs = msi_vecs;
307
308	if (irq_delivery == DIRECTED)
309		rc = zpci_set_directed_irq(zdev);
310	else
311		rc = zpci_set_airq(zdev);
312	if (rc)
313		return rc;
314
315	return (msi_vecs == nvec) ? 0 : msi_vecs;
316}
317
318void arch_teardown_msi_irqs(struct pci_dev *pdev)
319{
320	struct zpci_dev *zdev = to_zpci(pdev);
321	struct msi_desc *msi;
322	int rc;
323
324	/* Disable interrupts */
325	if (irq_delivery == DIRECTED)
326		rc = zpci_clear_directed_irq(zdev);
327	else
328		rc = zpci_clear_airq(zdev);
329	if (rc)
330		return;
331
332	/* Release MSI interrupts */
333	for_each_pci_msi_entry(msi, pdev) {
334		if (!msi->irq)
335			continue;
336		if (msi->msi_attrib.is_msix)
337			__pci_msix_desc_mask_irq(msi, 1);
338		else
339			__pci_msi_desc_mask_irq(msi, 1, 1);
340		irq_set_msi_desc(msi->irq, NULL);
341		irq_free_desc(msi->irq);
342		msi->msg.address_lo = 0;
343		msi->msg.address_hi = 0;
344		msi->msg.data = 0;
345		msi->irq = 0;
346	}
347
348	if (zdev->aisb != -1UL) {
349		zpci_ibv[zdev->aisb] = NULL;
350		airq_iv_free_bit(zpci_sbv, zdev->aisb);
351		zdev->aisb = -1UL;
352	}
353	if (zdev->aibv) {
354		airq_iv_release(zdev->aibv);
355		zdev->aibv = NULL;
356	}
357
358	if ((irq_delivery == DIRECTED) && zdev->msi_first_bit != -1U)
359		airq_iv_free(zpci_ibv[0], zdev->msi_first_bit, zdev->msi_nr_irqs);
360}
361
362static struct airq_struct zpci_airq = {
363	.handler = zpci_floating_irq_handler,
364	.isc = PCI_ISC,
365};
366
367static void __init cpu_enable_directed_irq(void *unused)
368{
369	union zpci_sic_iib iib = {{0}};
370
371	iib.cdiib.dibv_addr = (u64) zpci_ibv[smp_processor_id()]->vector;
372
373	__zpci_set_irq_ctrl(SIC_IRQ_MODE_SET_CPU, 0, &iib);
374	zpci_set_irq_ctrl(SIC_IRQ_MODE_D_SINGLE, PCI_ISC);
375}
376
377static int __init zpci_directed_irq_init(void)
378{
379	union zpci_sic_iib iib = {{0}};
380	unsigned int cpu;
381
382	zpci_sbv = airq_iv_create(num_possible_cpus(), 0);
383	if (!zpci_sbv)
384		return -ENOMEM;
385
386	iib.diib.isc = PCI_ISC;
387	iib.diib.nr_cpus = num_possible_cpus();
388	iib.diib.disb_addr = (u64) zpci_sbv->vector;
389	__zpci_set_irq_ctrl(SIC_IRQ_MODE_DIRECT, 0, &iib);
390
391	zpci_ibv = kcalloc(num_possible_cpus(), sizeof(*zpci_ibv),
392			   GFP_KERNEL);
393	if (!zpci_ibv)
394		return -ENOMEM;
395
396	for_each_possible_cpu(cpu) {
397		/*
398		 * Per CPU IRQ vectors look the same but bit-allocation
399		 * is only done on the first vector.
400		 */
401		zpci_ibv[cpu] = airq_iv_create(cache_line_size() * BITS_PER_BYTE,
402					       AIRQ_IV_DATA |
403					       AIRQ_IV_CACHELINE |
404					       (!cpu ? AIRQ_IV_ALLOC : 0));
405		if (!zpci_ibv[cpu])
406			return -ENOMEM;
407	}
408	on_each_cpu(cpu_enable_directed_irq, NULL, 1);
409
410	zpci_irq_chip.irq_set_affinity = zpci_set_irq_affinity;
411
412	return 0;
413}
414
415static int __init zpci_floating_irq_init(void)
416{
417	zpci_ibv = kcalloc(ZPCI_NR_DEVICES, sizeof(*zpci_ibv), GFP_KERNEL);
418	if (!zpci_ibv)
419		return -ENOMEM;
420
421	zpci_sbv = airq_iv_create(ZPCI_NR_DEVICES, AIRQ_IV_ALLOC);
422	if (!zpci_sbv)
423		goto out_free;
424
425	return 0;
426
427out_free:
428	kfree(zpci_ibv);
429	return -ENOMEM;
430}
431
432int __init zpci_irq_init(void)
433{
434	int rc;
435
436	irq_delivery = sclp.has_dirq ? DIRECTED : FLOATING;
437	if (s390_pci_force_floating)
438		irq_delivery = FLOATING;
439
440	if (irq_delivery == DIRECTED)
441		zpci_airq.handler = zpci_directed_irq_handler;
442
443	rc = register_adapter_interrupt(&zpci_airq);
444	if (rc)
445		goto out;
446	/* Set summary to 1 to be called every time for the ISC. */
447	*zpci_airq.lsi_ptr = 1;
448
449	switch (irq_delivery) {
450	case FLOATING:
451		rc = zpci_floating_irq_init();
452		break;
453	case DIRECTED:
454		rc = zpci_directed_irq_init();
455		break;
456	}
457
458	if (rc)
459		goto out_airq;
460
461	/*
462	 * Enable floating IRQs (with suppression after one IRQ). When using
463	 * directed IRQs this enables the fallback path.
464	 */
465	zpci_set_irq_ctrl(SIC_IRQ_MODE_SINGLE, PCI_ISC);
466
467	return 0;
468out_airq:
469	unregister_adapter_interrupt(&zpci_airq);
470out:
471	return rc;
472}
473
474void __init zpci_irq_exit(void)
475{
476	unsigned int cpu;
477
478	if (irq_delivery == DIRECTED) {
479		for_each_possible_cpu(cpu) {
480			airq_iv_release(zpci_ibv[cpu]);
481		}
482	}
483	kfree(zpci_ibv);
484	if (zpci_sbv)
485		airq_iv_release(zpci_sbv);
486	unregister_adapter_interrupt(&zpci_airq);
487}