1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/types.h>
  3#include <linux/kernel.h>
  4#include <linux/irq.h>
  5#include <linux/smp.h>
  6#include <linux/interrupt.h>
  7#include <linux/init.h>
  8#include <linux/cpu.h>
  9#include <linux/of.h>
 10#include <linux/spinlock.h>
 11#include <linux/msi.h>
 12
 
 13#include <asm/smp.h>
 14#include <asm/machdep.h>
 15#include <asm/irq.h>
 16#include <asm/errno.h>
 17#include <asm/xics.h>
 18#include <asm/rtas.h>
 19
 20/* RTAS service tokens */
 21static int ibm_get_xive;
 22static int ibm_set_xive;
 23static int ibm_int_on;
 24static int ibm_int_off;
 25
 
 
 
 
 
 
 
 
 
 
 
 
 
 26static void ics_rtas_unmask_irq(struct irq_data *d)
 27{
 28	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 29	int call_status;
 30	int server;
 31
 32	pr_devel("xics: unmask virq %d [hw 0x%x]\n", d->irq, hw_irq);
 33
 34	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 35		return;
 36
 37	server = xics_get_irq_server(d->irq, irq_data_get_affinity_mask(d), 0);
 38
 39	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq, server,
 40				DEFAULT_PRIORITY);
 41	if (call_status != 0) {
 42		printk(KERN_ERR
 43			"%s: ibm_set_xive irq %u server %x returned %d\n",
 44			__func__, hw_irq, server, call_status);
 45		return;
 46	}
 47
 48	/* Now unmask the interrupt (often a no-op) */
 49	call_status = rtas_call(ibm_int_on, 1, 1, NULL, hw_irq);
 50	if (call_status != 0) {
 51		printk(KERN_ERR "%s: ibm_int_on irq=%u returned %d\n",
 52			__func__, hw_irq, call_status);
 53		return;
 54	}
 55}
 56
 57static unsigned int ics_rtas_startup(struct irq_data *d)
 58{
 
 
 
 
 
 
 
 
 
 59	/* unmask it */
 60	ics_rtas_unmask_irq(d);
 61	return 0;
 62}
 63
 64static void ics_rtas_mask_real_irq(unsigned int hw_irq)
 65{
 66	int call_status;
 67
 68	if (hw_irq == XICS_IPI)
 69		return;
 70
 71	call_status = rtas_call(ibm_int_off, 1, 1, NULL, hw_irq);
 72	if (call_status != 0) {
 73		printk(KERN_ERR "%s: ibm_int_off irq=%u returned %d\n",
 74			__func__, hw_irq, call_status);
 75		return;
 76	}
 77
 78	/* Have to set XIVE to 0xff to be able to remove a slot */
 79	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq,
 80				xics_default_server, 0xff);
 81	if (call_status != 0) {
 82		printk(KERN_ERR "%s: ibm_set_xive(0xff) irq=%u returned %d\n",
 83			__func__, hw_irq, call_status);
 84		return;
 85	}
 86}
 87
 88static void ics_rtas_mask_irq(struct irq_data *d)
 89{
 90	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 91
 92	pr_devel("xics: mask virq %d [hw 0x%x]\n", d->irq, hw_irq);
 93
 94	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 95		return;
 96	ics_rtas_mask_real_irq(hw_irq);
 97}
 98
 99static int ics_rtas_set_affinity(struct irq_data *d,
100				 const struct cpumask *cpumask,
101				 bool force)
102{
103	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
104	int status;
105	int xics_status[2];
106	int irq_server;
107
108	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
109		return -1;
110
111	status = rtas_call(ibm_get_xive, 1, 3, xics_status, hw_irq);
112
113	if (status) {
114		printk(KERN_ERR "%s: ibm,get-xive irq=%u returns %d\n",
115			__func__, hw_irq, status);
116		return -1;
117	}
118
119	irq_server = xics_get_irq_server(d->irq, cpumask, 1);
120	if (irq_server == -1) {
121		pr_warn("%s: No online cpus in the mask %*pb for irq %d\n",
122			__func__, cpumask_pr_args(cpumask), d->irq);
 
 
 
123		return -1;
124	}
125
126	pr_debug("%s: irq %d [hw 0x%x] server: 0x%x\n", __func__, d->irq,
127		 hw_irq, irq_server);
128
129	status = rtas_call(ibm_set_xive, 3, 1, NULL,
130			   hw_irq, irq_server, xics_status[1]);
131
132	if (status) {
133		printk(KERN_ERR "%s: ibm,set-xive irq=%u returns %d\n",
134			__func__, hw_irq, status);
135		return -1;
136	}
137
138	return IRQ_SET_MASK_OK;
139}
140
141static struct irq_chip ics_rtas_irq_chip = {
142	.name = "XICS",
143	.irq_startup = ics_rtas_startup,
144	.irq_mask = ics_rtas_mask_irq,
145	.irq_unmask = ics_rtas_unmask_irq,
146	.irq_eoi = NULL, /* Patched at init time */
147	.irq_set_affinity = ics_rtas_set_affinity,
148	.irq_set_type = xics_set_irq_type,
149	.irq_retrigger = xics_retrigger,
150};
151
152static int ics_rtas_check(struct ics *ics, unsigned int hw_irq)
153{
 
154	int status[2];
155	int rc;
156
157	if (WARN_ON(hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS))
158		return -EINVAL;
159
160	/* Check if RTAS knows about this interrupt */
161	rc = rtas_call(ibm_get_xive, 1, 3, status, hw_irq);
162	if (rc)
163		return -ENXIO;
164
 
 
 
165	return 0;
166}
167
168static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec)
169{
170	ics_rtas_mask_real_irq(vec);
171}
172
173static long ics_rtas_get_server(struct ics *ics, unsigned long vec)
174{
175	int rc, status[2];
176
177	rc = rtas_call(ibm_get_xive, 1, 3, status, vec);
178	if (rc)
179		return -1;
180	return status[0];
181}
182
183static int ics_rtas_host_match(struct ics *ics, struct device_node *node)
184{
185	/* IBM machines have interrupt parents of various funky types for things
186	 * like vdevices, events, etc... The trick we use here is to match
187	 * everything here except the legacy 8259 which is compatible "chrp,iic"
188	 */
189	return !of_device_is_compatible(node, "chrp,iic");
190}
191
192/* Only one global & state struct ics */
193static struct ics ics_rtas = {
194	.check		= ics_rtas_check,
195	.mask_unknown	= ics_rtas_mask_unknown,
196	.get_server	= ics_rtas_get_server,
197	.host_match	= ics_rtas_host_match,
198	.chip = &ics_rtas_irq_chip,
199};
200
201__init int ics_rtas_init(void)
202{
203	ibm_get_xive = rtas_function_token(RTAS_FN_IBM_GET_XIVE);
204	ibm_set_xive = rtas_function_token(RTAS_FN_IBM_SET_XIVE);
205	ibm_int_on  = rtas_function_token(RTAS_FN_IBM_INT_ON);
206	ibm_int_off = rtas_function_token(RTAS_FN_IBM_INT_OFF);
207
208	/* We enable the RTAS "ICS" if RTAS is present with the
209	 * appropriate tokens
210	 */
211	if (ibm_get_xive == RTAS_UNKNOWN_SERVICE ||
212	    ibm_set_xive == RTAS_UNKNOWN_SERVICE)
213		return -ENODEV;
214
215	/* We need to patch our irq chip's EOI to point to the
216	 * right ICP
217	 */
218	ics_rtas_irq_chip.irq_eoi = icp_ops->eoi;
219
220	/* Register ourselves */
221	xics_register_ics(&ics_rtas);
222
223	return 0;
224}
225

 
  1#include <linux/types.h>
  2#include <linux/kernel.h>
  3#include <linux/irq.h>
  4#include <linux/smp.h>
  5#include <linux/interrupt.h>
  6#include <linux/init.h>
  7#include <linux/cpu.h>
  8#include <linux/of.h>
  9#include <linux/spinlock.h>
 10#include <linux/msi.h>
 11
 12#include <asm/prom.h>
 13#include <asm/smp.h>
 14#include <asm/machdep.h>
 15#include <asm/irq.h>
 16#include <asm/errno.h>
 17#include <asm/xics.h>
 18#include <asm/rtas.h>
 19
 20/* RTAS service tokens */
 21static int ibm_get_xive;
 22static int ibm_set_xive;
 23static int ibm_int_on;
 24static int ibm_int_off;
 25
 26static int ics_rtas_map(struct ics *ics, unsigned int virq);
 27static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec);
 28static long ics_rtas_get_server(struct ics *ics, unsigned long vec);
 29static int ics_rtas_host_match(struct ics *ics, struct device_node *node);
 30
 31/* Only one global & state struct ics */
 32static struct ics ics_rtas = {
 33	.map		= ics_rtas_map,
 34	.mask_unknown	= ics_rtas_mask_unknown,
 35	.get_server	= ics_rtas_get_server,
 36	.host_match	= ics_rtas_host_match,
 37};
 38
 39static void ics_rtas_unmask_irq(struct irq_data *d)
 40{
 41	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
 42	int call_status;
 43	int server;
 44
 45	pr_devel("xics: unmask virq %d [hw 0x%x]\n", d->irq, hw_irq);
 46
 47	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
 48		return;
 49
 50	server = xics_get_irq_server(d->irq, d->affinity, 0);
 51
 52	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq, server,
 53				DEFAULT_PRIORITY);
 54	if (call_status != 0) {
 55		printk(KERN_ERR
 56			"%s: ibm_set_xive irq %u server %x returned %d\n",
 57			__func__, hw_irq, server, call_status);
 58		return;
 59	}
 60
 61	/* Now unmask the interrupt (often a no-op) */
 62	call_status = rtas_call(ibm_int_on, 1, 1, NULL, hw_irq);
 63	if (call_status != 0) {
 64		printk(KERN_ERR "%s: ibm_int_on irq=%u returned %d\n",
 65			__func__, hw_irq, call_status);
 66		return;
 67	}
 68}
 69
 70static unsigned int ics_rtas_startup(struct irq_data *d)
 71{
 72#ifdef CONFIG_PCI_MSI
 73	/*
 74	 * The generic MSI code returns with the interrupt disabled on the
 75	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
 76	 * at that level, so we do it here by hand.
 77	 */
 78	if (d->msi_desc)
 79		unmask_msi_irq(d);
 80#endif
 81	/* unmask it */
 82	ics_rtas_unmask_irq(d);
 83	return 0;
 84}
 85
 86static void ics_rtas_mask_real_irq(unsigned int hw_irq)
 87{
 88	int call_status;
 89
 90	if (hw_irq == XICS_IPI)
 91		return;
 92
 93	call_status = rtas_call(ibm_int_off, 1, 1, NULL, hw_irq);
 94	if (call_status != 0) {
 95		printk(KERN_ERR "%s: ibm_int_off irq=%u returned %d\n",
 96			__func__, hw_irq, call_status);
 97		return;
 98	}
 99
100	/* Have to set XIVE to 0xff to be able to remove a slot */
101	call_status = rtas_call(ibm_set_xive, 3, 1, NULL, hw_irq,
102				xics_default_server, 0xff);
103	if (call_status != 0) {
104		printk(KERN_ERR "%s: ibm_set_xive(0xff) irq=%u returned %d\n",
105			__func__, hw_irq, call_status);
106		return;
107	}
108}
109
110static void ics_rtas_mask_irq(struct irq_data *d)
111{
112	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
113
114	pr_devel("xics: mask virq %d [hw 0x%x]\n", d->irq, hw_irq);
115
116	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
117		return;
118	ics_rtas_mask_real_irq(hw_irq);
119}
120
121static int ics_rtas_set_affinity(struct irq_data *d,
122				 const struct cpumask *cpumask,
123				 bool force)
124{
125	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
126	int status;
127	int xics_status[2];
128	int irq_server;
129
130	if (hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS)
131		return -1;
132
133	status = rtas_call(ibm_get_xive, 1, 3, xics_status, hw_irq);
134
135	if (status) {
136		printk(KERN_ERR "%s: ibm,get-xive irq=%u returns %d\n",
137			__func__, hw_irq, status);
138		return -1;
139	}
140
141	irq_server = xics_get_irq_server(d->irq, cpumask, 1);
142	if (irq_server == -1) {
143		char cpulist[128];
144		cpumask_scnprintf(cpulist, sizeof(cpulist), cpumask);
145		printk(KERN_WARNING
146			"%s: No online cpus in the mask %s for irq %d\n",
147			__func__, cpulist, d->irq);
148		return -1;
149	}
150
 
 
 
151	status = rtas_call(ibm_set_xive, 3, 1, NULL,
152			   hw_irq, irq_server, xics_status[1]);
153
154	if (status) {
155		printk(KERN_ERR "%s: ibm,set-xive irq=%u returns %d\n",
156			__func__, hw_irq, status);
157		return -1;
158	}
159
160	return IRQ_SET_MASK_OK;
161}
162
163static struct irq_chip ics_rtas_irq_chip = {
164	.name = "XICS",
165	.irq_startup = ics_rtas_startup,
166	.irq_mask = ics_rtas_mask_irq,
167	.irq_unmask = ics_rtas_unmask_irq,
168	.irq_eoi = NULL, /* Patched at init time */
169	.irq_set_affinity = ics_rtas_set_affinity
 
 
170};
171
172static int ics_rtas_map(struct ics *ics, unsigned int virq)
173{
174	unsigned int hw_irq = (unsigned int)virq_to_hw(virq);
175	int status[2];
176	int rc;
177
178	if (WARN_ON(hw_irq == XICS_IPI || hw_irq == XICS_IRQ_SPURIOUS))
179		return -EINVAL;
180
181	/* Check if RTAS knows about this interrupt */
182	rc = rtas_call(ibm_get_xive, 1, 3, status, hw_irq);
183	if (rc)
184		return -ENXIO;
185
186	irq_set_chip_and_handler(virq, &ics_rtas_irq_chip, handle_fasteoi_irq);
187	irq_set_chip_data(virq, &ics_rtas);
188
189	return 0;
190}
191
192static void ics_rtas_mask_unknown(struct ics *ics, unsigned long vec)
193{
194	ics_rtas_mask_real_irq(vec);
195}
196
197static long ics_rtas_get_server(struct ics *ics, unsigned long vec)
198{
199	int rc, status[2];
200
201	rc = rtas_call(ibm_get_xive, 1, 3, status, vec);
202	if (rc)
203		return -1;
204	return status[0];
205}
206
207static int ics_rtas_host_match(struct ics *ics, struct device_node *node)
208{
209	/* IBM machines have interrupt parents of various funky types for things
210	 * like vdevices, events, etc... The trick we use here is to match
211	 * everything here except the legacy 8259 which is compatible "chrp,iic"
212	 */
213	return !of_device_is_compatible(node, "chrp,iic");
214}
215
216int ics_rtas_init(void)
 
 
 
 
 
 
 
 
 
217{
218	ibm_get_xive = rtas_token("ibm,get-xive");
219	ibm_set_xive = rtas_token("ibm,set-xive");
220	ibm_int_on  = rtas_token("ibm,int-on");
221	ibm_int_off = rtas_token("ibm,int-off");
222
223	/* We enable the RTAS "ICS" if RTAS is present with the
224	 * appropriate tokens
225	 */
226	if (ibm_get_xive == RTAS_UNKNOWN_SERVICE ||
227	    ibm_set_xive == RTAS_UNKNOWN_SERVICE)
228		return -ENODEV;
229
230	/* We need to patch our irq chip's EOI to point to the
231	 * right ICP
232	 */
233	ics_rtas_irq_chip.irq_eoi = icp_ops->eoi;
234
235	/* Register ourselves */
236	xics_register_ics(&ics_rtas);
237
238	return 0;
239}
240