xref: /openbmc/qemu/hw/ppc/pnv_lpc.c (revision e7bbc9b1)
1 /*
2  * QEMU PowerPC PowerNV LPC controller
3  *
4  * Copyright (c) 2016, IBM Corporation.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "sysemu/sysemu.h"
22 #include "target/ppc/cpu.h"
23 #include "qapi/error.h"
24 #include "qemu/log.h"
25 #include "hw/isa/isa.h"
26 
27 #include "hw/ppc/pnv.h"
28 #include "hw/ppc/pnv_lpc.h"
29 #include "hw/ppc/pnv_xscom.h"
30 #include "hw/ppc/fdt.h"
31 
32 #include <libfdt.h>
33 
34 enum {
35     ECCB_CTL    = 0,
36     ECCB_RESET  = 1,
37     ECCB_STAT   = 2,
38     ECCB_DATA   = 3,
39 };
40 
41 /* OPB Master LS registers */
42 #define OPB_MASTER_LS_IRQ_STAT  0x50
43 #define   OPB_MASTER_IRQ_LPC            0x00000800
44 #define OPB_MASTER_LS_IRQ_MASK  0x54
45 #define OPB_MASTER_LS_IRQ_POL   0x58
46 #define OPB_MASTER_LS_IRQ_INPUT 0x5c
47 
48 /* LPC HC registers */
49 #define LPC_HC_FW_SEG_IDSEL     0x24
50 #define LPC_HC_FW_RD_ACC_SIZE   0x28
51 #define   LPC_HC_FW_RD_1B               0x00000000
52 #define   LPC_HC_FW_RD_2B               0x01000000
53 #define   LPC_HC_FW_RD_4B               0x02000000
54 #define   LPC_HC_FW_RD_16B              0x04000000
55 #define   LPC_HC_FW_RD_128B             0x07000000
56 #define LPC_HC_IRQSER_CTRL      0x30
57 #define   LPC_HC_IRQSER_EN              0x80000000
58 #define   LPC_HC_IRQSER_QMODE           0x40000000
59 #define   LPC_HC_IRQSER_START_MASK      0x03000000
60 #define   LPC_HC_IRQSER_START_4CLK      0x00000000
61 #define   LPC_HC_IRQSER_START_6CLK      0x01000000
62 #define   LPC_HC_IRQSER_START_8CLK      0x02000000
63 #define LPC_HC_IRQMASK          0x34    /* same bit defs as LPC_HC_IRQSTAT */
64 #define LPC_HC_IRQSTAT          0x38
65 #define   LPC_HC_IRQ_SERIRQ0            0x80000000 /* all bits down to ... */
66 #define   LPC_HC_IRQ_SERIRQ16           0x00008000 /* IRQ16=IOCHK#, IRQ2=SMI# */
67 #define   LPC_HC_IRQ_SERIRQ_ALL         0xffff8000
68 #define   LPC_HC_IRQ_LRESET             0x00000400
69 #define   LPC_HC_IRQ_SYNC_ABNORM_ERR    0x00000080
70 #define   LPC_HC_IRQ_SYNC_NORESP_ERR    0x00000040
71 #define   LPC_HC_IRQ_SYNC_NORM_ERR      0x00000020
72 #define   LPC_HC_IRQ_SYNC_TIMEOUT_ERR   0x00000010
73 #define   LPC_HC_IRQ_SYNC_TARG_TAR_ERR  0x00000008
74 #define   LPC_HC_IRQ_SYNC_BM_TAR_ERR    0x00000004
75 #define   LPC_HC_IRQ_SYNC_BM0_REQ       0x00000002
76 #define   LPC_HC_IRQ_SYNC_BM1_REQ       0x00000001
77 #define LPC_HC_ERROR_ADDRESS    0x40
78 
79 #define LPC_OPB_SIZE            0x100000000ull
80 
81 #define ISA_IO_SIZE             0x00010000
82 #define ISA_MEM_SIZE            0x10000000
83 #define ISA_FW_SIZE             0x10000000
84 #define LPC_IO_OPB_ADDR         0xd0010000
85 #define LPC_IO_OPB_SIZE         0x00010000
86 #define LPC_MEM_OPB_ADDR        0xe0010000
87 #define LPC_MEM_OPB_SIZE        0x10000000
88 #define LPC_FW_OPB_ADDR         0xf0000000
89 #define LPC_FW_OPB_SIZE         0x10000000
90 
91 #define LPC_OPB_REGS_OPB_ADDR   0xc0010000
92 #define LPC_OPB_REGS_OPB_SIZE   0x00002000
93 #define LPC_HC_REGS_OPB_ADDR    0xc0012000
94 #define LPC_HC_REGS_OPB_SIZE    0x00001000
95 
96 
97 static int pnv_lpc_dt_xscom(PnvXScomInterface *dev, void *fdt, int xscom_offset)
98 {
99     const char compat[] = "ibm,power8-lpc\0ibm,lpc";
100     char *name;
101     int offset;
102     uint32_t lpc_pcba = PNV_XSCOM_LPC_BASE;
103     uint32_t reg[] = {
104         cpu_to_be32(lpc_pcba),
105         cpu_to_be32(PNV_XSCOM_LPC_SIZE)
106     };
107 
108     name = g_strdup_printf("isa@%x", lpc_pcba);
109     offset = fdt_add_subnode(fdt, xscom_offset, name);
110     _FDT(offset);
111     g_free(name);
112 
113     _FDT((fdt_setprop(fdt, offset, "reg", reg, sizeof(reg))));
114     _FDT((fdt_setprop_cell(fdt, offset, "#address-cells", 2)));
115     _FDT((fdt_setprop_cell(fdt, offset, "#size-cells", 1)));
116     _FDT((fdt_setprop(fdt, offset, "compatible", compat, sizeof(compat))));
117     return 0;
118 }
119 
120 /*
121  * These read/write handlers of the OPB address space should be common
122  * with the P9 LPC Controller which uses direct MMIOs.
123  *
124  * TODO: rework to use address_space_stq() and address_space_ldq()
125  * instead.
126  */
127 static bool opb_read(PnvLpcController *lpc, uint32_t addr, uint8_t *data,
128                      int sz)
129 {
130     /* XXX Handle access size limits and FW read caching here */
131     return !address_space_rw(&lpc->opb_as, addr, MEMTXATTRS_UNSPECIFIED,
132                              data, sz, false);
133 }
134 
135 static bool opb_write(PnvLpcController *lpc, uint32_t addr, uint8_t *data,
136                       int sz)
137 {
138     /* XXX Handle access size limits here */
139     return !address_space_rw(&lpc->opb_as, addr, MEMTXATTRS_UNSPECIFIED,
140                              data, sz, true);
141 }
142 
143 #define ECCB_CTL_READ           PPC_BIT(15)
144 #define ECCB_CTL_SZ_LSH         (63 - 7)
145 #define ECCB_CTL_SZ_MASK        PPC_BITMASK(4, 7)
146 #define ECCB_CTL_ADDR_MASK      PPC_BITMASK(32, 63)
147 
148 #define ECCB_STAT_OP_DONE       PPC_BIT(52)
149 #define ECCB_STAT_OP_ERR        PPC_BIT(52)
150 #define ECCB_STAT_RD_DATA_LSH   (63 - 37)
151 #define ECCB_STAT_RD_DATA_MASK  (0xffffffff << ECCB_STAT_RD_DATA_LSH)
152 
153 static void pnv_lpc_do_eccb(PnvLpcController *lpc, uint64_t cmd)
154 {
155     /* XXX Check for magic bits at the top, addr size etc... */
156     unsigned int sz = (cmd & ECCB_CTL_SZ_MASK) >> ECCB_CTL_SZ_LSH;
157     uint32_t opb_addr = cmd & ECCB_CTL_ADDR_MASK;
158     uint8_t data[8];
159     bool success;
160 
161     if (sz > sizeof(data)) {
162         qemu_log_mask(LOG_GUEST_ERROR,
163             "ECCB: invalid operation at @0x%08x size %d\n", opb_addr, sz);
164         return;
165     }
166 
167     if (cmd & ECCB_CTL_READ) {
168         success = opb_read(lpc, opb_addr, data, sz);
169         if (success) {
170             lpc->eccb_stat_reg = ECCB_STAT_OP_DONE |
171                     (((uint64_t)data[0]) << 24 |
172                      ((uint64_t)data[1]) << 16 |
173                      ((uint64_t)data[2]) <<  8 |
174                      ((uint64_t)data[3])) << ECCB_STAT_RD_DATA_LSH;
175         } else {
176             lpc->eccb_stat_reg = ECCB_STAT_OP_DONE |
177                     (0xffffffffull << ECCB_STAT_RD_DATA_LSH);
178         }
179     } else {
180         data[0] = lpc->eccb_data_reg >> 24;
181         data[1] = lpc->eccb_data_reg >> 16;
182         data[2] = lpc->eccb_data_reg >>  8;
183         data[3] = lpc->eccb_data_reg;
184 
185         success = opb_write(lpc, opb_addr, data, sz);
186         lpc->eccb_stat_reg = ECCB_STAT_OP_DONE;
187     }
188     /* XXX Which error bit (if any) to signal OPB error ? */
189 }
190 
191 static uint64_t pnv_lpc_xscom_read(void *opaque, hwaddr addr, unsigned size)
192 {
193     PnvLpcController *lpc = PNV_LPC(opaque);
194     uint32_t offset = addr >> 3;
195     uint64_t val = 0;
196 
197     switch (offset & 3) {
198     case ECCB_CTL:
199     case ECCB_RESET:
200         val = 0;
201         break;
202     case ECCB_STAT:
203         val = lpc->eccb_stat_reg;
204         lpc->eccb_stat_reg = 0;
205         break;
206     case ECCB_DATA:
207         val = ((uint64_t)lpc->eccb_data_reg) << 32;
208         break;
209     }
210     return val;
211 }
212 
213 static void pnv_lpc_xscom_write(void *opaque, hwaddr addr,
214                                 uint64_t val, unsigned size)
215 {
216     PnvLpcController *lpc = PNV_LPC(opaque);
217     uint32_t offset = addr >> 3;
218 
219     switch (offset & 3) {
220     case ECCB_CTL:
221         pnv_lpc_do_eccb(lpc, val);
222         break;
223     case ECCB_RESET:
224         /*  XXXX  */
225         break;
226     case ECCB_STAT:
227         break;
228     case ECCB_DATA:
229         lpc->eccb_data_reg = val >> 32;
230         break;
231     }
232 }
233 
234 static const MemoryRegionOps pnv_lpc_xscom_ops = {
235     .read = pnv_lpc_xscom_read,
236     .write = pnv_lpc_xscom_write,
237     .valid.min_access_size = 8,
238     .valid.max_access_size = 8,
239     .impl.min_access_size = 8,
240     .impl.max_access_size = 8,
241     .endianness = DEVICE_BIG_ENDIAN,
242 };
243 
244 static void pnv_lpc_eval_irqs(PnvLpcController *lpc)
245 {
246     bool lpc_to_opb_irq = false;
247 
248     /* Update LPC controller to OPB line */
249     if (lpc->lpc_hc_irqser_ctrl & LPC_HC_IRQSER_EN) {
250         uint32_t irqs;
251 
252         irqs = lpc->lpc_hc_irqstat & lpc->lpc_hc_irqmask;
253         lpc_to_opb_irq = (irqs != 0);
254     }
255 
256     /* We don't honor the polarity register, it's pointless and unused
257      * anyway
258      */
259     if (lpc_to_opb_irq) {
260         lpc->opb_irq_input |= OPB_MASTER_IRQ_LPC;
261     } else {
262         lpc->opb_irq_input &= ~OPB_MASTER_IRQ_LPC;
263     }
264 
265     /* Update OPB internal latch */
266     lpc->opb_irq_stat |= lpc->opb_irq_input & lpc->opb_irq_mask;
267 
268     /* Reflect the interrupt */
269     pnv_psi_irq_set(lpc->psi, PSIHB_IRQ_LPC_I2C, lpc->opb_irq_stat != 0);
270 }
271 
272 static uint64_t lpc_hc_read(void *opaque, hwaddr addr, unsigned size)
273 {
274     PnvLpcController *lpc = opaque;
275     uint64_t val = 0xfffffffffffffffful;
276 
277     switch (addr) {
278     case LPC_HC_FW_SEG_IDSEL:
279         val =  lpc->lpc_hc_fw_seg_idsel;
280         break;
281     case LPC_HC_FW_RD_ACC_SIZE:
282         val =  lpc->lpc_hc_fw_rd_acc_size;
283         break;
284     case LPC_HC_IRQSER_CTRL:
285         val =  lpc->lpc_hc_irqser_ctrl;
286         break;
287     case LPC_HC_IRQMASK:
288         val =  lpc->lpc_hc_irqmask;
289         break;
290     case LPC_HC_IRQSTAT:
291         val =  lpc->lpc_hc_irqstat;
292         break;
293     case LPC_HC_ERROR_ADDRESS:
294         val =  lpc->lpc_hc_error_addr;
295         break;
296     default:
297         qemu_log_mask(LOG_UNIMP, "LPC HC Unimplemented register: Ox%"
298                       HWADDR_PRIx "\n", addr);
299     }
300     return val;
301 }
302 
303 static void lpc_hc_write(void *opaque, hwaddr addr, uint64_t val,
304                          unsigned size)
305 {
306     PnvLpcController *lpc = opaque;
307 
308     /* XXX Filter out reserved bits */
309 
310     switch (addr) {
311     case LPC_HC_FW_SEG_IDSEL:
312         /* XXX Actually figure out how that works as this impact
313          * memory regions/aliases
314          */
315         lpc->lpc_hc_fw_seg_idsel = val;
316         break;
317     case LPC_HC_FW_RD_ACC_SIZE:
318         lpc->lpc_hc_fw_rd_acc_size = val;
319         break;
320     case LPC_HC_IRQSER_CTRL:
321         lpc->lpc_hc_irqser_ctrl = val;
322         pnv_lpc_eval_irqs(lpc);
323         break;
324     case LPC_HC_IRQMASK:
325         lpc->lpc_hc_irqmask = val;
326         pnv_lpc_eval_irqs(lpc);
327         break;
328     case LPC_HC_IRQSTAT:
329         lpc->lpc_hc_irqstat &= ~val;
330         pnv_lpc_eval_irqs(lpc);
331         break;
332     case LPC_HC_ERROR_ADDRESS:
333         break;
334     default:
335         qemu_log_mask(LOG_UNIMP, "LPC HC Unimplemented register: Ox%"
336                       HWADDR_PRIx "\n", addr);
337     }
338 }
339 
340 static const MemoryRegionOps lpc_hc_ops = {
341     .read = lpc_hc_read,
342     .write = lpc_hc_write,
343     .endianness = DEVICE_BIG_ENDIAN,
344     .valid = {
345         .min_access_size = 4,
346         .max_access_size = 4,
347     },
348     .impl = {
349         .min_access_size = 4,
350         .max_access_size = 4,
351     },
352 };
353 
354 static uint64_t opb_master_read(void *opaque, hwaddr addr, unsigned size)
355 {
356     PnvLpcController *lpc = opaque;
357     uint64_t val = 0xfffffffffffffffful;
358 
359     switch (addr) {
360     case OPB_MASTER_LS_IRQ_STAT:
361         val = lpc->opb_irq_stat;
362         break;
363     case OPB_MASTER_LS_IRQ_MASK:
364         val = lpc->opb_irq_mask;
365         break;
366     case OPB_MASTER_LS_IRQ_POL:
367         val = lpc->opb_irq_pol;
368         break;
369     case OPB_MASTER_LS_IRQ_INPUT:
370         val = lpc->opb_irq_input;
371         break;
372     default:
373         qemu_log_mask(LOG_UNIMP, "OPB MASTER Unimplemented register: Ox%"
374                       HWADDR_PRIx "\n", addr);
375     }
376 
377     return val;
378 }
379 
380 static void opb_master_write(void *opaque, hwaddr addr,
381                              uint64_t val, unsigned size)
382 {
383     PnvLpcController *lpc = opaque;
384 
385     switch (addr) {
386     case OPB_MASTER_LS_IRQ_STAT:
387         lpc->opb_irq_stat &= ~val;
388         pnv_lpc_eval_irqs(lpc);
389         break;
390     case OPB_MASTER_LS_IRQ_MASK:
391         lpc->opb_irq_mask = val;
392         pnv_lpc_eval_irqs(lpc);
393         break;
394     case OPB_MASTER_LS_IRQ_POL:
395         lpc->opb_irq_pol = val;
396         pnv_lpc_eval_irqs(lpc);
397         break;
398     case OPB_MASTER_LS_IRQ_INPUT:
399         /* Read only */
400         break;
401     default:
402         qemu_log_mask(LOG_UNIMP, "OPB MASTER Unimplemented register: Ox%"
403                       HWADDR_PRIx "\n", addr);
404     }
405 }
406 
407 static const MemoryRegionOps opb_master_ops = {
408     .read = opb_master_read,
409     .write = opb_master_write,
410     .endianness = DEVICE_BIG_ENDIAN,
411     .valid = {
412         .min_access_size = 4,
413         .max_access_size = 4,
414     },
415     .impl = {
416         .min_access_size = 4,
417         .max_access_size = 4,
418     },
419 };
420 
421 static void pnv_lpc_realize(DeviceState *dev, Error **errp)
422 {
423     PnvLpcController *lpc = PNV_LPC(dev);
424     Object *obj;
425     Error *error = NULL;
426 
427     /* Reg inits */
428     lpc->lpc_hc_fw_rd_acc_size = LPC_HC_FW_RD_4B;
429 
430     /* Create address space and backing MR for the OPB bus */
431     memory_region_init(&lpc->opb_mr, OBJECT(dev), "lpc-opb", 0x100000000ull);
432     address_space_init(&lpc->opb_as, &lpc->opb_mr, "lpc-opb");
433 
434     /* Create ISA IO and Mem space regions which are the root of
435      * the ISA bus (ie, ISA address spaces). We don't create a
436      * separate one for FW which we alias to memory.
437      */
438     memory_region_init(&lpc->isa_io, OBJECT(dev), "isa-io", ISA_IO_SIZE);
439     memory_region_init(&lpc->isa_mem, OBJECT(dev), "isa-mem", ISA_MEM_SIZE);
440     memory_region_init(&lpc->isa_fw, OBJECT(dev),  "isa-fw", ISA_FW_SIZE);
441 
442     /* Create windows from the OPB space to the ISA space */
443     memory_region_init_alias(&lpc->opb_isa_io, OBJECT(dev), "lpc-isa-io",
444                              &lpc->isa_io, 0, LPC_IO_OPB_SIZE);
445     memory_region_add_subregion(&lpc->opb_mr, LPC_IO_OPB_ADDR,
446                                 &lpc->opb_isa_io);
447     memory_region_init_alias(&lpc->opb_isa_mem, OBJECT(dev), "lpc-isa-mem",
448                              &lpc->isa_mem, 0, LPC_MEM_OPB_SIZE);
449     memory_region_add_subregion(&lpc->opb_mr, LPC_MEM_OPB_ADDR,
450                                 &lpc->opb_isa_mem);
451     memory_region_init_alias(&lpc->opb_isa_fw, OBJECT(dev), "lpc-isa-fw",
452                              &lpc->isa_fw, 0, LPC_FW_OPB_SIZE);
453     memory_region_add_subregion(&lpc->opb_mr, LPC_FW_OPB_ADDR,
454                                 &lpc->opb_isa_fw);
455 
456     /* Create MMIO regions for LPC HC and OPB registers */
457     memory_region_init_io(&lpc->opb_master_regs, OBJECT(dev), &opb_master_ops,
458                           lpc, "lpc-opb-master", LPC_OPB_REGS_OPB_SIZE);
459     memory_region_add_subregion(&lpc->opb_mr, LPC_OPB_REGS_OPB_ADDR,
460                                 &lpc->opb_master_regs);
461     memory_region_init_io(&lpc->lpc_hc_regs, OBJECT(dev), &lpc_hc_ops, lpc,
462                           "lpc-hc", LPC_HC_REGS_OPB_SIZE);
463     memory_region_add_subregion(&lpc->opb_mr, LPC_HC_REGS_OPB_ADDR,
464                                 &lpc->lpc_hc_regs);
465 
466     /* XScom region for LPC registers */
467     pnv_xscom_region_init(&lpc->xscom_regs, OBJECT(dev),
468                           &pnv_lpc_xscom_ops, lpc, "xscom-lpc",
469                           PNV_XSCOM_LPC_SIZE);
470 
471     /* get PSI object from chip */
472     obj = object_property_get_link(OBJECT(dev), "psi", &error);
473     if (!obj) {
474         error_setg(errp, "%s: required link 'psi' not found: %s",
475                    __func__, error_get_pretty(error));
476         return;
477     }
478     lpc->psi = PNV_PSI(obj);
479 }
480 
481 static void pnv_lpc_class_init(ObjectClass *klass, void *data)
482 {
483     DeviceClass *dc = DEVICE_CLASS(klass);
484     PnvXScomInterfaceClass *xdc = PNV_XSCOM_INTERFACE_CLASS(klass);
485 
486     xdc->dt_xscom = pnv_lpc_dt_xscom;
487 
488     dc->realize = pnv_lpc_realize;
489 }
490 
491 static const TypeInfo pnv_lpc_info = {
492     .name          = TYPE_PNV_LPC,
493     .parent        = TYPE_DEVICE,
494     .instance_size = sizeof(PnvLpcController),
495     .class_init    = pnv_lpc_class_init,
496     .interfaces = (InterfaceInfo[]) {
497         { TYPE_PNV_XSCOM_INTERFACE },
498         { }
499     }
500 };
501 
502 static void pnv_lpc_register_types(void)
503 {
504     type_register_static(&pnv_lpc_info);
505 }
506 
507 type_init(pnv_lpc_register_types)
508 
509 /* If we don't use the built-in LPC interrupt deserializer, we need
510  * to provide a set of qirqs for the ISA bus or things will go bad.
511  *
512  * Most machines using pre-Naples chips (without said deserializer)
513  * have a CPLD that will collect the SerIRQ and shoot them as a
514  * single level interrupt to the P8 chip. So let's setup a hook
515  * for doing just that.
516  */
517 static void pnv_lpc_isa_irq_handler_cpld(void *opaque, int n, int level)
518 {
519     PnvMachineState *pnv = PNV_MACHINE(qdev_get_machine());
520     uint32_t old_state = pnv->cpld_irqstate;
521     PnvLpcController *lpc = PNV_LPC(opaque);
522 
523     if (level) {
524         pnv->cpld_irqstate |= 1u << n;
525     } else {
526         pnv->cpld_irqstate &= ~(1u << n);
527     }
528 
529     if (pnv->cpld_irqstate != old_state) {
530         pnv_psi_irq_set(lpc->psi, PSIHB_IRQ_EXTERNAL, pnv->cpld_irqstate != 0);
531     }
532 }
533 
534 static void pnv_lpc_isa_irq_handler(void *opaque, int n, int level)
535 {
536     PnvLpcController *lpc = PNV_LPC(opaque);
537 
538     /* The Naples HW latches the 1 levels, clearing is done by SW */
539     if (level) {
540         lpc->lpc_hc_irqstat |= LPC_HC_IRQ_SERIRQ0 >> n;
541         pnv_lpc_eval_irqs(lpc);
542     }
543 }
544 
545 ISABus *pnv_lpc_isa_create(PnvLpcController *lpc, bool use_cpld, Error **errp)
546 {
547     Error *local_err = NULL;
548     ISABus *isa_bus;
549     qemu_irq *irqs;
550     qemu_irq_handler handler;
551 
552     /* let isa_bus_new() create its own bridge on SysBus otherwise
553      * devices speficied on the command line won't find the bus and
554      * will fail to create.
555      */
556     isa_bus = isa_bus_new(NULL, &lpc->isa_mem, &lpc->isa_io, &local_err);
557     if (local_err) {
558         error_propagate(errp, local_err);
559         return NULL;
560     }
561 
562     /* Not all variants have a working serial irq decoder. If not,
563      * handling of LPC interrupts becomes a platform issue (some
564      * platforms have a CPLD to do it).
565      */
566     if (use_cpld) {
567         handler = pnv_lpc_isa_irq_handler_cpld;
568     } else {
569         handler = pnv_lpc_isa_irq_handler;
570     }
571 
572     irqs = qemu_allocate_irqs(handler, lpc, ISA_NUM_IRQS);
573 
574     isa_bus_irqs(isa_bus, irqs);
575     return isa_bus;
576 }
577