Merge tag 'locks-v3.16-2' of git://git.samba.org/jlayton/linux
[linux/fpc-iii.git] / arch / powerpc / sysdev / xics / icp-native.c
blobde8d9483bbe89136042d0685680c6bddc815849a
1 /*
2 * Copyright 2011 IBM Corporation.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
9 */
11 #include <linux/types.h>
12 #include <linux/kernel.h>
13 #include <linux/irq.h>
14 #include <linux/smp.h>
15 #include <linux/interrupt.h>
16 #include <linux/init.h>
17 #include <linux/cpu.h>
18 #include <linux/of.h>
19 #include <linux/spinlock.h>
20 #include <linux/module.h>
22 #include <asm/prom.h>
23 #include <asm/io.h>
24 #include <asm/smp.h>
25 #include <asm/irq.h>
26 #include <asm/errno.h>
27 #include <asm/xics.h>
28 #include <asm/kvm_ppc.h>
29 #include <asm/dbell.h>
31 struct icp_ipl {
32 union {
33 u32 word;
34 u8 bytes[4];
35 } xirr_poll;
36 union {
37 u32 word;
38 u8 bytes[4];
39 } xirr;
40 u32 dummy;
41 union {
42 u32 word;
43 u8 bytes[4];
44 } qirr;
45 u32 link_a;
46 u32 link_b;
47 u32 link_c;
50 static struct icp_ipl __iomem *icp_native_regs[NR_CPUS];
52 static inline unsigned int icp_native_get_xirr(void)
54 int cpu = smp_processor_id();
55 unsigned int xirr;
57 /* Handled an interrupt latched by KVM */
58 xirr = kvmppc_get_xics_latch();
59 if (xirr)
60 return xirr;
62 return in_be32(&icp_native_regs[cpu]->xirr.word);
65 static inline void icp_native_set_xirr(unsigned int value)
67 int cpu = smp_processor_id();
69 out_be32(&icp_native_regs[cpu]->xirr.word, value);
72 static inline void icp_native_set_cppr(u8 value)
74 int cpu = smp_processor_id();
76 out_8(&icp_native_regs[cpu]->xirr.bytes[0], value);
79 static inline void icp_native_set_qirr(int n_cpu, u8 value)
81 out_8(&icp_native_regs[n_cpu]->qirr.bytes[0], value);
84 static void icp_native_set_cpu_priority(unsigned char cppr)
86 xics_set_base_cppr(cppr);
87 icp_native_set_cppr(cppr);
88 iosync();
91 void icp_native_eoi(struct irq_data *d)
93 unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
95 iosync();
96 icp_native_set_xirr((xics_pop_cppr() << 24) | hw_irq);
99 static void icp_native_teardown_cpu(void)
101 int cpu = smp_processor_id();
103 /* Clear any pending IPI */
104 icp_native_set_qirr(cpu, 0xff);
107 static void icp_native_flush_ipi(void)
109 /* We take the ipi irq but and never return so we
110 * need to EOI the IPI, but want to leave our priority 0
112 * should we check all the other interrupts too?
113 * should we be flagging idle loop instead?
114 * or creating some task to be scheduled?
117 icp_native_set_xirr((0x00 << 24) | XICS_IPI);
120 static unsigned int icp_native_get_irq(void)
122 unsigned int xirr = icp_native_get_xirr();
123 unsigned int vec = xirr & 0x00ffffff;
124 unsigned int irq;
126 if (vec == XICS_IRQ_SPURIOUS)
127 return NO_IRQ;
129 irq = irq_find_mapping(xics_host, vec);
130 if (likely(irq != NO_IRQ)) {
131 xics_push_cppr(vec);
132 return irq;
135 /* We don't have a linux mapping, so have rtas mask it. */
136 xics_mask_unknown_vec(vec);
138 /* We might learn about it later, so EOI it */
139 icp_native_set_xirr(xirr);
141 return NO_IRQ;
144 #ifdef CONFIG_SMP
146 static void icp_native_cause_ipi(int cpu, unsigned long data)
148 kvmppc_set_host_ipi(cpu, 1);
149 #ifdef CONFIG_PPC_DOORBELL
150 if (cpu_has_feature(CPU_FTR_DBELL) &&
151 (cpumask_test_cpu(cpu, cpu_sibling_mask(smp_processor_id()))))
152 doorbell_cause_ipi(cpu, data);
153 else
154 #endif
155 icp_native_set_qirr(cpu, IPI_PRIORITY);
158 void xics_wake_cpu(int cpu)
160 icp_native_set_qirr(cpu, IPI_PRIORITY);
162 EXPORT_SYMBOL_GPL(xics_wake_cpu);
164 static irqreturn_t icp_native_ipi_action(int irq, void *dev_id)
166 int cpu = smp_processor_id();
168 kvmppc_set_host_ipi(cpu, 0);
169 icp_native_set_qirr(cpu, 0xff);
171 return smp_ipi_demux();
174 #endif /* CONFIG_SMP */
176 static int __init icp_native_map_one_cpu(int hw_id, unsigned long addr,
177 unsigned long size)
179 char *rname;
180 int i, cpu = -1;
182 /* This may look gross but it's good enough for now, we don't quite
183 * have a hard -> linux processor id matching.
185 for_each_possible_cpu(i) {
186 if (!cpu_present(i))
187 continue;
188 if (hw_id == get_hard_smp_processor_id(i)) {
189 cpu = i;
190 break;
194 /* Fail, skip that CPU. Don't print, it's normal, some XICS come up
195 * with way more entries in there than you have CPUs
197 if (cpu == -1)
198 return 0;
200 rname = kasprintf(GFP_KERNEL, "CPU %d [0x%x] Interrupt Presentation",
201 cpu, hw_id);
203 if (!request_mem_region(addr, size, rname)) {
204 pr_warning("icp_native: Could not reserve ICP MMIO"
205 " for CPU %d, interrupt server #0x%x\n",
206 cpu, hw_id);
207 return -EBUSY;
210 icp_native_regs[cpu] = ioremap(addr, size);
211 kvmppc_set_xics_phys(cpu, addr);
212 if (!icp_native_regs[cpu]) {
213 pr_warning("icp_native: Failed ioremap for CPU %d, "
214 "interrupt server #0x%x, addr %#lx\n",
215 cpu, hw_id, addr);
216 release_mem_region(addr, size);
217 return -ENOMEM;
219 return 0;
222 static int __init icp_native_init_one_node(struct device_node *np,
223 unsigned int *indx)
225 unsigned int ilen;
226 const __be32 *ireg;
227 int i;
228 int reg_tuple_size;
229 int num_servers = 0;
231 /* This code does the theorically broken assumption that the interrupt
232 * server numbers are the same as the hard CPU numbers.
233 * This happens to be the case so far but we are playing with fire...
234 * should be fixed one of these days. -BenH.
236 ireg = of_get_property(np, "ibm,interrupt-server-ranges", &ilen);
238 /* Do that ever happen ? we'll know soon enough... but even good'old
239 * f80 does have that property ..
241 WARN_ON((ireg == NULL) || (ilen != 2*sizeof(u32)));
243 if (ireg) {
244 *indx = of_read_number(ireg, 1);
245 if (ilen >= 2*sizeof(u32))
246 num_servers = of_read_number(ireg + 1, 1);
249 ireg = of_get_property(np, "reg", &ilen);
250 if (!ireg) {
251 pr_err("icp_native: Can't find interrupt reg property");
252 return -1;
255 reg_tuple_size = (of_n_addr_cells(np) + of_n_size_cells(np)) * 4;
256 if (((ilen % reg_tuple_size) != 0)
257 || (num_servers && (num_servers != (ilen / reg_tuple_size)))) {
258 pr_err("icp_native: ICP reg len (%d) != num servers (%d)",
259 ilen / reg_tuple_size, num_servers);
260 return -1;
263 for (i = 0; i < (ilen / reg_tuple_size); i++) {
264 struct resource r;
265 int err;
267 err = of_address_to_resource(np, i, &r);
268 if (err) {
269 pr_err("icp_native: Could not translate ICP MMIO"
270 " for interrupt server 0x%x (%d)\n", *indx, err);
271 return -1;
274 if (icp_native_map_one_cpu(*indx, r.start, resource_size(&r)))
275 return -1;
277 (*indx)++;
279 return 0;
282 static const struct icp_ops icp_native_ops = {
283 .get_irq = icp_native_get_irq,
284 .eoi = icp_native_eoi,
285 .set_priority = icp_native_set_cpu_priority,
286 .teardown_cpu = icp_native_teardown_cpu,
287 .flush_ipi = icp_native_flush_ipi,
288 #ifdef CONFIG_SMP
289 .ipi_action = icp_native_ipi_action,
290 .cause_ipi = icp_native_cause_ipi,
291 #endif
294 int __init icp_native_init(void)
296 struct device_node *np;
297 u32 indx = 0;
298 int found = 0;
300 for_each_compatible_node(np, NULL, "ibm,ppc-xicp")
301 if (icp_native_init_one_node(np, &indx) == 0)
302 found = 1;
303 if (!found) {
304 for_each_node_by_type(np,
305 "PowerPC-External-Interrupt-Presentation") {
306 if (icp_native_init_one_node(np, &indx) == 0)
307 found = 1;
311 if (found == 0)
312 return -ENODEV;
314 icp_ops = &icp_native_ops;
316 return 0;