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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * ARC ARConnect (MultiCore IP) support (formerly known as MCIP)
  4 *
  5 * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
 
 
 
 
  6 */
  7
  8#include <linux/smp.h>
  9#include <linux/irq.h>
 10#include <linux/irqchip/chained_irq.h>
 11#include <linux/spinlock.h>
 12#include <soc/arc/mcip.h>
 13#include <asm/irqflags-arcv2.h>
 14#include <asm/setup.h>
 15
 16static DEFINE_RAW_SPINLOCK(mcip_lock);
 17
 18#ifdef CONFIG_SMP
 19
 20static char smp_cpuinfo_buf[128];
 21
 22/*
 23 * Set mask to halt GFRC if any online core in SMP cluster is halted.
 24 * Only works for ARC HS v3.0+, on earlier versions has no effect.
 25 */
 26static void mcip_update_gfrc_halt_mask(int cpu)
 27{
 28	struct bcr_generic gfrc;
 29	unsigned long flags;
 30	u32 gfrc_halt_mask;
 31
 32	READ_BCR(ARC_REG_GFRC_BUILD, gfrc);
 33
 34	/*
 35	 * CMD_GFRC_SET_CORE and CMD_GFRC_READ_CORE commands were added in
 36	 * GFRC 0x3 version.
 37	 */
 38	if (gfrc.ver < 0x3)
 39		return;
 40
 41	raw_spin_lock_irqsave(&mcip_lock, flags);
 42
 43	__mcip_cmd(CMD_GFRC_READ_CORE, 0);
 44	gfrc_halt_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
 45	gfrc_halt_mask |= BIT(cpu);
 46	__mcip_cmd_data(CMD_GFRC_SET_CORE, 0, gfrc_halt_mask);
 47
 48	raw_spin_unlock_irqrestore(&mcip_lock, flags);
 49}
 50
 51static void mcip_update_debug_halt_mask(int cpu)
 52{
 53	u32 mcip_mask = 0;
 54	unsigned long flags;
 55
 56	raw_spin_lock_irqsave(&mcip_lock, flags);
 57
 58	/*
 59	 * mcip_mask is same for CMD_DEBUG_SET_SELECT and CMD_DEBUG_SET_MASK
 60	 * commands. So read it once instead of reading both CMD_DEBUG_READ_MASK
 61	 * and CMD_DEBUG_READ_SELECT.
 62	 */
 63	__mcip_cmd(CMD_DEBUG_READ_SELECT, 0);
 64	mcip_mask = read_aux_reg(ARC_REG_MCIP_READBACK);
 65
 66	mcip_mask |= BIT(cpu);
 67
 68	__mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, mcip_mask);
 69	/*
 70	 * Parameter specified halt cause:
 71	 * STATUS32[H]/actionpoint/breakpoint/self-halt
 72	 * We choose all of them (0xF).
 73	 */
 74	__mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xF, mcip_mask);
 75
 76	raw_spin_unlock_irqrestore(&mcip_lock, flags);
 77}
 78
 79static void mcip_setup_per_cpu(int cpu)
 80{
 81	struct mcip_bcr mp;
 82
 83	READ_BCR(ARC_REG_MCIP_BCR, mp);
 84
 85	smp_ipi_irq_setup(cpu, IPI_IRQ);
 86	smp_ipi_irq_setup(cpu, SOFTIRQ_IRQ);
 87
 88	/* Update GFRC halt mask as new CPU came online */
 89	if (mp.gfrc)
 90		mcip_update_gfrc_halt_mask(cpu);
 91
 92	/* Update MCIP debug mask as new CPU came online */
 93	if (mp.dbg)
 94		mcip_update_debug_halt_mask(cpu);
 95}
 96
 97static void mcip_ipi_send(int cpu)
 98{
 99	unsigned long flags;
100	int ipi_was_pending;
101
102	/* ARConnect can only send IPI to others */
103	if (unlikely(cpu == raw_smp_processor_id())) {
104		arc_softirq_trigger(SOFTIRQ_IRQ);
105		return;
106	}
107
108	raw_spin_lock_irqsave(&mcip_lock, flags);
109
110	/*
111	 * If receiver already has a pending interrupt, elide sending this one.
112	 * Linux cross core calling works well with concurrent IPIs
113	 * coalesced into one
114	 * see arch/arc/kernel/smp.c: ipi_send_msg_one()
115	 */
116	__mcip_cmd(CMD_INTRPT_READ_STATUS, cpu);
117	ipi_was_pending = read_aux_reg(ARC_REG_MCIP_READBACK);
118	if (!ipi_was_pending)
119		__mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu);
120
121	raw_spin_unlock_irqrestore(&mcip_lock, flags);
122}
123
124static void mcip_ipi_clear(int irq)
125{
126	unsigned int cpu, c;
127	unsigned long flags;
128
129	if (unlikely(irq == SOFTIRQ_IRQ)) {
130		arc_softirq_clear(irq);
131		return;
132	}
133
134	raw_spin_lock_irqsave(&mcip_lock, flags);
135
136	/* Who sent the IPI */
137	__mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0);
138
139	cpu = read_aux_reg(ARC_REG_MCIP_READBACK);	/* 1,2,4,8... */
140
141	/*
142	 * In rare case, multiple concurrent IPIs sent to same target can
143	 * possibly be coalesced by MCIP into 1 asserted IRQ, so @cpus can be
144	 * "vectored" (multiple bits sets) as opposed to typical single bit
145	 */
146	do {
147		c = __ffs(cpu);			/* 0,1,2,3 */
148		__mcip_cmd(CMD_INTRPT_GENERATE_ACK, c);
149		cpu &= ~(1U << c);
150	} while (cpu);
151
152	raw_spin_unlock_irqrestore(&mcip_lock, flags);
153}
154
155static void mcip_probe_n_setup(void)
156{
157	struct mcip_bcr mp;
158
159	READ_BCR(ARC_REG_MCIP_BCR, mp);
160
161	sprintf(smp_cpuinfo_buf,
162		"Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n",
163		mp.ver, mp.num_cores,
164		IS_AVAIL1(mp.ipi, "IPI "),
165		IS_AVAIL1(mp.idu, "IDU "),
166		IS_AVAIL1(mp.dbg, "DEBUG "),
167		IS_AVAIL1(mp.gfrc, "GFRC"));
 
 
 
 
 
 
 
168}
169
170struct plat_smp_ops plat_smp_ops = {
171	.info		= smp_cpuinfo_buf,
172	.init_early_smp	= mcip_probe_n_setup,
173	.init_per_cpu	= mcip_setup_per_cpu,
174	.ipi_send	= mcip_ipi_send,
175	.ipi_clear	= mcip_ipi_clear,
176};
177
178#endif
179
180/***************************************************************************
181 * ARCv2 Interrupt Distribution Unit (IDU)
182 *
183 * Connects external "COMMON" IRQs to core intc, providing:
184 *  -dynamic routing (IRQ affinity)
185 *  -load balancing (Round Robin interrupt distribution)
186 *  -1:N distribution
187 *
188 * It physically resides in the MCIP hw block
189 */
190
191#include <linux/irqchip.h>
192#include <linux/of.h>
193#include <linux/of_irq.h>
194
195/*
196 * Set the DEST for @cmn_irq to @cpu_mask (1 bit per core)
197 */
198static void idu_set_dest(unsigned int cmn_irq, unsigned int cpu_mask)
199{
200	__mcip_cmd_data(CMD_IDU_SET_DEST, cmn_irq, cpu_mask);
201}
202
203static void idu_set_mode(unsigned int cmn_irq, bool set_lvl, unsigned int lvl,
204			 bool set_distr, unsigned int distr)
205{
206	union {
207		unsigned int word;
208		struct {
209			unsigned int distr:2, pad:2, lvl:1, pad2:27;
210		};
211	} data;
212
213	data.word = __mcip_cmd_read(CMD_IDU_READ_MODE, cmn_irq);
214	if (set_distr)
215		data.distr = distr;
216	if (set_lvl)
217		data.lvl = lvl;
218	__mcip_cmd_data(CMD_IDU_SET_MODE, cmn_irq, data.word);
219}
220
221static void idu_irq_mask_raw(irq_hw_number_t hwirq)
222{
223	unsigned long flags;
224
225	raw_spin_lock_irqsave(&mcip_lock, flags);
226	__mcip_cmd_data(CMD_IDU_SET_MASK, hwirq, 1);
227	raw_spin_unlock_irqrestore(&mcip_lock, flags);
228}
229
230static void idu_irq_mask(struct irq_data *data)
231{
232	idu_irq_mask_raw(data->hwirq);
233}
234
235static void idu_irq_unmask(struct irq_data *data)
236{
237	unsigned long flags;
238
239	raw_spin_lock_irqsave(&mcip_lock, flags);
240	__mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 0);
241	raw_spin_unlock_irqrestore(&mcip_lock, flags);
242}
243
244static void idu_irq_ack(struct irq_data *data)
245{
246	unsigned long flags;
247
248	raw_spin_lock_irqsave(&mcip_lock, flags);
249	__mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
250	raw_spin_unlock_irqrestore(&mcip_lock, flags);
251}
252
253static void idu_irq_mask_ack(struct irq_data *data)
254{
255	unsigned long flags;
256
257	raw_spin_lock_irqsave(&mcip_lock, flags);
258	__mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 1);
259	__mcip_cmd(CMD_IDU_ACK_CIRQ, data->hwirq);
260	raw_spin_unlock_irqrestore(&mcip_lock, flags);
261}
262
263static int
264idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
265		     bool force)
266{
267	unsigned long flags;
268	cpumask_t online;
269	unsigned int destination_bits;
270	unsigned int distribution_mode;
271
272	/* errout if no online cpu per @cpumask */
273	if (!cpumask_and(&online, cpumask, cpu_online_mask))
274		return -EINVAL;
275
276	raw_spin_lock_irqsave(&mcip_lock, flags);
277
278	destination_bits = cpumask_bits(&online)[0];
279	idu_set_dest(data->hwirq, destination_bits);
280
281	if (ffs(destination_bits) == fls(destination_bits))
282		distribution_mode = IDU_M_DISTRI_DEST;
283	else
284		distribution_mode = IDU_M_DISTRI_RR;
285
286	idu_set_mode(data->hwirq, false, 0, true, distribution_mode);
287
288	raw_spin_unlock_irqrestore(&mcip_lock, flags);
289
290	return IRQ_SET_MASK_OK;
291}
292
293static int idu_irq_set_type(struct irq_data *data, u32 type)
294{
295	unsigned long flags;
296
297	/*
298	 * ARCv2 IDU HW does not support inverse polarity, so these are the
299	 * only interrupt types supported.
300	 */
301	if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_LEVEL_HIGH))
302		return -EINVAL;
303
304	raw_spin_lock_irqsave(&mcip_lock, flags);
305
306	idu_set_mode(data->hwirq, true,
307		     type & IRQ_TYPE_EDGE_RISING ? IDU_M_TRIG_EDGE :
308						   IDU_M_TRIG_LEVEL,
309		     false, 0);
310
311	raw_spin_unlock_irqrestore(&mcip_lock, flags);
312
313	return 0;
314}
315
316static void idu_irq_enable(struct irq_data *data)
317{
318	/*
319	 * By default send all common interrupts to all available online CPUs.
320	 * The affinity of common interrupts in IDU must be set manually since
321	 * in some cases the kernel will not call irq_set_affinity() by itself:
322	 *   1. When the kernel is not configured with support of SMP.
323	 *   2. When the kernel is configured with support of SMP but upper
324	 *      interrupt controllers does not support setting of the affinity
325	 *      and cannot propagate it to IDU.
326	 */
327	idu_irq_set_affinity(data, cpu_online_mask, false);
328	idu_irq_unmask(data);
329}
330
331static struct irq_chip idu_irq_chip = {
332	.name			= "MCIP IDU Intc",
333	.irq_mask		= idu_irq_mask,
334	.irq_unmask		= idu_irq_unmask,
335	.irq_ack		= idu_irq_ack,
336	.irq_mask_ack		= idu_irq_mask_ack,
337	.irq_enable		= idu_irq_enable,
338	.irq_set_type		= idu_irq_set_type,
339#ifdef CONFIG_SMP
340	.irq_set_affinity       = idu_irq_set_affinity,
341#endif
342
343};
344
 
 
345static void idu_cascade_isr(struct irq_desc *desc)
346{
347	struct irq_domain *idu_domain = irq_desc_get_handler_data(desc);
348	struct irq_chip *core_chip = irq_desc_get_chip(desc);
349	irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc));
350	irq_hw_number_t idu_hwirq = core_hwirq - FIRST_EXT_IRQ;
351
352	chained_irq_enter(core_chip, desc);
353	generic_handle_domain_irq(idu_domain, idu_hwirq);
354	chained_irq_exit(core_chip, desc);
355}
356
357static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq)
358{
359	irq_set_chip_and_handler(virq, &idu_irq_chip, handle_level_irq);
360	irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
361
362	return 0;
363}
364
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
365static const struct irq_domain_ops idu_irq_ops = {
366	.xlate	= irq_domain_xlate_onetwocell,
367	.map	= idu_irq_map,
368};
369
370/*
371 * [16, 23]: Statically assigned always private-per-core (Timers, WDT, IPI)
372 * [24, 23+C]: If C > 0 then "C" common IRQs
373 * [24+C, N]: Not statically assigned, private-per-core
374 */
375
376
377static int __init
378idu_of_init(struct device_node *intc, struct device_node *parent)
379{
380	struct irq_domain *domain;
381	int nr_irqs;
 
382	int i, virq;
383	struct mcip_bcr mp;
384	struct mcip_idu_bcr idu_bcr;
385
386	READ_BCR(ARC_REG_MCIP_BCR, mp);
387
388	if (!mp.idu)
389		panic("IDU not detected, but DeviceTree using it");
390
391	READ_BCR(ARC_REG_MCIP_IDU_BCR, idu_bcr);
392	nr_irqs = mcip_idu_bcr_to_nr_irqs(idu_bcr);
393
394	pr_info("MCIP: IDU supports %u common irqs\n", nr_irqs);
395
396	domain = irq_domain_add_linear(intc, nr_irqs, &idu_irq_ops, NULL);
397
398	/* Parent interrupts (core-intc) are already mapped */
399
400	for (i = 0; i < nr_irqs; i++) {
401		/* Mask all common interrupts by default */
402		idu_irq_mask_raw(i);
403
404		/*
405		 * Return parent uplink IRQs (towards core intc) 24,25,.....
406		 * this step has been done before already
407		 * however we need it to get the parent virq and set IDU handler
408		 * as first level isr
409		 */
410		virq = irq_create_mapping(NULL, i + FIRST_EXT_IRQ);
411		BUG_ON(!virq);
 
 
412		irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain);
413	}
414
415	__mcip_cmd(CMD_IDU_ENABLE, 0);
416
417	return 0;
418}
419IRQCHIP_DECLARE(arcv2_idu_intc, "snps,archs-idu-intc", idu_of_init);
v4.10.11
 
  1/*
  2 * ARC ARConnect (MultiCore IP) support (formerly known as MCIP)
  3 *
  4 * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10
 11#include <linux/smp.h>
 12#include <linux/irq.h>
 13#include <linux/irqchip/chained_irq.h>
 14#include <linux/spinlock.h>
 15#include <soc/arc/mcip.h>
 16#include <asm/irqflags-arcv2.h>
 17#include <asm/setup.h>
 18
 19static DEFINE_RAW_SPINLOCK(mcip_lock);
 20
 21#ifdef CONFIG_SMP
 22
 23static char smp_cpuinfo_buf[128];
 24
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 25static void mcip_setup_per_cpu(int cpu)
 26{
 
 
 
 
 27	smp_ipi_irq_setup(cpu, IPI_IRQ);
 28	smp_ipi_irq_setup(cpu, SOFTIRQ_IRQ);
 
 
 
 
 
 
 
 
 29}
 30
 31static void mcip_ipi_send(int cpu)
 32{
 33	unsigned long flags;
 34	int ipi_was_pending;
 35
 36	/* ARConnect can only send IPI to others */
 37	if (unlikely(cpu == raw_smp_processor_id())) {
 38		arc_softirq_trigger(SOFTIRQ_IRQ);
 39		return;
 40	}
 41
 42	raw_spin_lock_irqsave(&mcip_lock, flags);
 43
 44	/*
 45	 * If receiver already has a pending interrupt, elide sending this one.
 46	 * Linux cross core calling works well with concurrent IPIs
 47	 * coalesced into one
 48	 * see arch/arc/kernel/smp.c: ipi_send_msg_one()
 49	 */
 50	__mcip_cmd(CMD_INTRPT_READ_STATUS, cpu);
 51	ipi_was_pending = read_aux_reg(ARC_REG_MCIP_READBACK);
 52	if (!ipi_was_pending)
 53		__mcip_cmd(CMD_INTRPT_GENERATE_IRQ, cpu);
 54
 55	raw_spin_unlock_irqrestore(&mcip_lock, flags);
 56}
 57
 58static void mcip_ipi_clear(int irq)
 59{
 60	unsigned int cpu, c;
 61	unsigned long flags;
 62
 63	if (unlikely(irq == SOFTIRQ_IRQ)) {
 64		arc_softirq_clear(irq);
 65		return;
 66	}
 67
 68	raw_spin_lock_irqsave(&mcip_lock, flags);
 69
 70	/* Who sent the IPI */
 71	__mcip_cmd(CMD_INTRPT_CHECK_SOURCE, 0);
 72
 73	cpu = read_aux_reg(ARC_REG_MCIP_READBACK);	/* 1,2,4,8... */
 74
 75	/*
 76	 * In rare case, multiple concurrent IPIs sent to same target can
 77	 * possibly be coalesced by MCIP into 1 asserted IRQ, so @cpus can be
 78	 * "vectored" (multiple bits sets) as opposed to typical single bit
 79	 */
 80	do {
 81		c = __ffs(cpu);			/* 0,1,2,3 */
 82		__mcip_cmd(CMD_INTRPT_GENERATE_ACK, c);
 83		cpu &= ~(1U << c);
 84	} while (cpu);
 85
 86	raw_spin_unlock_irqrestore(&mcip_lock, flags);
 87}
 88
 89static void mcip_probe_n_setup(void)
 90{
 91	struct mcip_bcr mp;
 92
 93	READ_BCR(ARC_REG_MCIP_BCR, mp);
 94
 95	sprintf(smp_cpuinfo_buf,
 96		"Extn [SMP]\t: ARConnect (v%d): %d cores with %s%s%s%s\n",
 97		mp.ver, mp.num_cores,
 98		IS_AVAIL1(mp.ipi, "IPI "),
 99		IS_AVAIL1(mp.idu, "IDU "),
100		IS_AVAIL1(mp.dbg, "DEBUG "),
101		IS_AVAIL1(mp.gfrc, "GFRC"));
102
103	cpuinfo_arc700[0].extn.gfrc = mp.gfrc;
104
105	if (mp.dbg) {
106		__mcip_cmd_data(CMD_DEBUG_SET_SELECT, 0, 0xf);
107		__mcip_cmd_data(CMD_DEBUG_SET_MASK, 0xf, 0xf);
108	}
109}
110
111struct plat_smp_ops plat_smp_ops = {
112	.info		= smp_cpuinfo_buf,
113	.init_early_smp	= mcip_probe_n_setup,
114	.init_per_cpu	= mcip_setup_per_cpu,
115	.ipi_send	= mcip_ipi_send,
116	.ipi_clear	= mcip_ipi_clear,
117};
118
119#endif
120
121/***************************************************************************
122 * ARCv2 Interrupt Distribution Unit (IDU)
123 *
124 * Connects external "COMMON" IRQs to core intc, providing:
125 *  -dynamic routing (IRQ affinity)
126 *  -load balancing (Round Robin interrupt distribution)
127 *  -1:N distribution
128 *
129 * It physically resides in the MCIP hw block
130 */
131
132#include <linux/irqchip.h>
133#include <linux/of.h>
134#include <linux/of_irq.h>
135
136/*
137 * Set the DEST for @cmn_irq to @cpu_mask (1 bit per core)
138 */
139static void idu_set_dest(unsigned int cmn_irq, unsigned int cpu_mask)
140{
141	__mcip_cmd_data(CMD_IDU_SET_DEST, cmn_irq, cpu_mask);
142}
143
144static void idu_set_mode(unsigned int cmn_irq, unsigned int lvl,
145			   unsigned int distr)
146{
147	union {
148		unsigned int word;
149		struct {
150			unsigned int distr:2, pad:2, lvl:1, pad2:27;
151		};
152	} data;
153
154	data.distr = distr;
155	data.lvl = lvl;
 
 
 
156	__mcip_cmd_data(CMD_IDU_SET_MODE, cmn_irq, data.word);
157}
158
159static void idu_irq_mask(struct irq_data *data)
160{
161	unsigned long flags;
162
163	raw_spin_lock_irqsave(&mcip_lock, flags);
164	__mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 1);
165	raw_spin_unlock_irqrestore(&mcip_lock, flags);
166}
167
 
 
 
 
 
168static void idu_irq_unmask(struct irq_data *data)
169{
170	unsigned long flags;
171
172	raw_spin_lock_irqsave(&mcip_lock, flags);
173	__mcip_cmd_data(CMD_IDU_SET_MASK, data->hwirq, 0);
174	raw_spin_unlock_irqrestore(&mcip_lock, flags);
175}
176
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
177static int
178idu_irq_set_affinity(struct irq_data *data, const struct cpumask *cpumask,
179		     bool force)
180{
181	unsigned long flags;
182	cpumask_t online;
183	unsigned int destination_bits;
184	unsigned int distribution_mode;
185
186	/* errout if no online cpu per @cpumask */
187	if (!cpumask_and(&online, cpumask, cpu_online_mask))
188		return -EINVAL;
189
190	raw_spin_lock_irqsave(&mcip_lock, flags);
191
192	destination_bits = cpumask_bits(&online)[0];
193	idu_set_dest(data->hwirq, destination_bits);
194
195	if (ffs(destination_bits) == fls(destination_bits))
196		distribution_mode = IDU_M_DISTRI_DEST;
197	else
198		distribution_mode = IDU_M_DISTRI_RR;
199
200	idu_set_mode(data->hwirq, IDU_M_TRIG_LEVEL, distribution_mode);
201
202	raw_spin_unlock_irqrestore(&mcip_lock, flags);
203
204	return IRQ_SET_MASK_OK;
205}
206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
207static void idu_irq_enable(struct irq_data *data)
208{
209	/*
210	 * By default send all common interrupts to all available online CPUs.
211	 * The affinity of common interrupts in IDU must be set manually since
212	 * in some cases the kernel will not call irq_set_affinity() by itself:
213	 *   1. When the kernel is not configured with support of SMP.
214	 *   2. When the kernel is configured with support of SMP but upper
215	 *      interrupt controllers does not support setting of the affinity
216	 *      and cannot propagate it to IDU.
217	 */
218	idu_irq_set_affinity(data, cpu_online_mask, false);
219	idu_irq_unmask(data);
220}
221
222static struct irq_chip idu_irq_chip = {
223	.name			= "MCIP IDU Intc",
224	.irq_mask		= idu_irq_mask,
225	.irq_unmask		= idu_irq_unmask,
 
 
226	.irq_enable		= idu_irq_enable,
 
227#ifdef CONFIG_SMP
228	.irq_set_affinity       = idu_irq_set_affinity,
229#endif
230
231};
232
233static irq_hw_number_t idu_first_hwirq;
234
235static void idu_cascade_isr(struct irq_desc *desc)
236{
237	struct irq_domain *idu_domain = irq_desc_get_handler_data(desc);
238	struct irq_chip *core_chip = irq_desc_get_chip(desc);
239	irq_hw_number_t core_hwirq = irqd_to_hwirq(irq_desc_get_irq_data(desc));
240	irq_hw_number_t idu_hwirq = core_hwirq - idu_first_hwirq;
241
242	chained_irq_enter(core_chip, desc);
243	generic_handle_irq(irq_find_mapping(idu_domain, idu_hwirq));
244	chained_irq_exit(core_chip, desc);
245}
246
247static int idu_irq_map(struct irq_domain *d, unsigned int virq, irq_hw_number_t hwirq)
248{
249	irq_set_chip_and_handler(virq, &idu_irq_chip, handle_level_irq);
250	irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
251
252	return 0;
253}
254
255static int idu_irq_xlate(struct irq_domain *d, struct device_node *n,
256			 const u32 *intspec, unsigned int intsize,
257			 irq_hw_number_t *out_hwirq, unsigned int *out_type)
258{
259	/*
260	 * Ignore value of interrupt distribution mode for common interrupts in
261	 * IDU which resides in intspec[1] since setting an affinity using value
262	 * from Device Tree is deprecated in ARC.
263	 */
264	*out_hwirq = intspec[0];
265	*out_type = IRQ_TYPE_NONE;
266
267	return 0;
268}
269
270static const struct irq_domain_ops idu_irq_ops = {
271	.xlate	= idu_irq_xlate,
272	.map	= idu_irq_map,
273};
274
275/*
276 * [16, 23]: Statically assigned always private-per-core (Timers, WDT, IPI)
277 * [24, 23+C]: If C > 0 then "C" common IRQs
278 * [24+C, N]: Not statically assigned, private-per-core
279 */
280
281
282static int __init
283idu_of_init(struct device_node *intc, struct device_node *parent)
284{
285	struct irq_domain *domain;
286	/* Read IDU BCR to confirm nr_irqs */
287	int nr_irqs = of_irq_count(intc);
288	int i, virq;
289	struct mcip_bcr mp;
 
290
291	READ_BCR(ARC_REG_MCIP_BCR, mp);
292
293	if (!mp.idu)
294		panic("IDU not detected, but DeviceTree using it");
295
296	pr_info("MCIP: IDU referenced from Devicetree %d irqs\n", nr_irqs);
 
 
 
297
298	domain = irq_domain_add_linear(intc, nr_irqs, &idu_irq_ops, NULL);
299
300	/* Parent interrupts (core-intc) are already mapped */
301
302	for (i = 0; i < nr_irqs; i++) {
 
 
 
303		/*
304		 * Return parent uplink IRQs (towards core intc) 24,25,.....
305		 * this step has been done before already
306		 * however we need it to get the parent virq and set IDU handler
307		 * as first level isr
308		 */
309		virq = irq_of_parse_and_map(intc, i);
310		if (!i)
311			idu_first_hwirq = irqd_to_hwirq(irq_get_irq_data(virq));
312
313		irq_set_chained_handler_and_data(virq, idu_cascade_isr, domain);
314	}
315
316	__mcip_cmd(CMD_IDU_ENABLE, 0);
317
318	return 0;
319}
320IRQCHIP_DECLARE(arcv2_idu_intc, "snps,archs-idu-intc", idu_of_init);