xref: /openbmc/qemu/hw/ppc/pnv_xscom.c (revision 8e6fe6b8)
1 /*
2  * QEMU PowerPC PowerNV XSCOM bus
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 "hw/hw.h"
22 #include "qemu/log.h"
23 #include "qemu/module.h"
24 #include "sysemu/hw_accel.h"
25 #include "target/ppc/cpu.h"
26 #include "hw/sysbus.h"
27 
28 #include "hw/ppc/fdt.h"
29 #include "hw/ppc/pnv.h"
30 #include "hw/ppc/pnv_xscom.h"
31 
32 #include <libfdt.h>
33 
34 /* PRD registers */
35 #define PRD_P8_IPOLL_REG_MASK           0x01020013
36 #define PRD_P8_IPOLL_REG_STATUS         0x01020014
37 #define PRD_P9_IPOLL_REG_MASK           0x000F0033
38 #define PRD_P9_IPOLL_REG_STATUS         0x000F0034
39 
40 static void xscom_complete(CPUState *cs, uint64_t hmer_bits)
41 {
42     /*
43      * TODO: When the read/write comes from the monitor, NULL is
44      * passed for the cpu, and no CPU completion is generated.
45      */
46     if (cs) {
47         PowerPCCPU *cpu = POWERPC_CPU(cs);
48         CPUPPCState *env = &cpu->env;
49 
50         /*
51          * TODO: Need a CPU helper to set HMER, also handle generation
52          * of HMIs
53          */
54         cpu_synchronize_state(cs);
55         env->spr[SPR_HMER] |= hmer_bits;
56     }
57 }
58 
59 static uint32_t pnv_xscom_pcba(PnvChip *chip, uint64_t addr)
60 {
61     addr &= (PNV_XSCOM_SIZE - 1);
62 
63     if (pnv_chip_is_power9(chip)) {
64         return addr >> 3;
65     } else {
66         return ((addr >> 4) & ~0xfull) | ((addr >> 3) & 0xf);
67     }
68 }
69 
70 static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
71 {
72     switch (pcba) {
73     case 0xf000f:
74         return PNV_CHIP_GET_CLASS(chip)->chip_cfam_id;
75     case 0x18002:       /* ECID2 */
76         return 0;
77 
78     case 0x1010c00:     /* PIBAM FIR */
79     case 0x1010c03:     /* PIBAM FIR MASK */
80 
81         /* PRD registers */
82     case PRD_P8_IPOLL_REG_MASK:
83     case PRD_P8_IPOLL_REG_STATUS:
84     case PRD_P9_IPOLL_REG_MASK:
85     case PRD_P9_IPOLL_REG_STATUS:
86 
87         /* P9 xscom reset */
88     case 0x0090018:     /* Receive status reg */
89     case 0x0090012:     /* log register */
90     case 0x0090013:     /* error register */
91 
92         /* P8 xscom reset */
93     case 0x2020007:     /* ADU stuff, log register */
94     case 0x2020009:     /* ADU stuff, error register */
95     case 0x202000f:     /* ADU stuff, receive status register*/
96         return 0;
97     case 0x2013f00:     /* PBA stuff */
98     case 0x2013f01:     /* PBA stuff */
99     case 0x2013f02:     /* PBA stuff */
100     case 0x2013f03:     /* PBA stuff */
101     case 0x2013f04:     /* PBA stuff */
102     case 0x2013f05:     /* PBA stuff */
103     case 0x2013f06:     /* PBA stuff */
104     case 0x2013f07:     /* PBA stuff */
105         return 0;
106     case 0x2013028:     /* CAPP stuff */
107     case 0x201302a:     /* CAPP stuff */
108     case 0x2013801:     /* CAPP stuff */
109     case 0x2013802:     /* CAPP stuff */
110         return 0;
111     default:
112         return -1;
113     }
114 }
115 
116 static bool xscom_write_default(PnvChip *chip, uint32_t pcba, uint64_t val)
117 {
118     /* We ignore writes to these */
119     switch (pcba) {
120     case 0xf000f:       /* chip id is RO */
121     case 0x1010c00:     /* PIBAM FIR */
122     case 0x1010c01:     /* PIBAM FIR */
123     case 0x1010c02:     /* PIBAM FIR */
124     case 0x1010c03:     /* PIBAM FIR MASK */
125     case 0x1010c04:     /* PIBAM FIR MASK */
126     case 0x1010c05:     /* PIBAM FIR MASK */
127         /* P9 xscom reset */
128     case 0x0090018:     /* Receive status reg */
129     case 0x0090012:     /* log register */
130     case 0x0090013:     /* error register */
131 
132         /* P8 xscom reset */
133     case 0x2020007:     /* ADU stuff, log register */
134     case 0x2020009:     /* ADU stuff, error register */
135     case 0x202000f:     /* ADU stuff, receive status register*/
136 
137     case 0x2013028:     /* CAPP stuff */
138     case 0x201302a:     /* CAPP stuff */
139     case 0x2013801:     /* CAPP stuff */
140     case 0x2013802:     /* CAPP stuff */
141 
142         /* P8 PRD registers */
143     case PRD_P8_IPOLL_REG_MASK:
144     case PRD_P8_IPOLL_REG_STATUS:
145     case PRD_P9_IPOLL_REG_MASK:
146     case PRD_P9_IPOLL_REG_STATUS:
147         return true;
148     default:
149         return false;
150     }
151 }
152 
153 static uint64_t xscom_read(void *opaque, hwaddr addr, unsigned width)
154 {
155     PnvChip *chip = opaque;
156     uint32_t pcba = pnv_xscom_pcba(chip, addr);
157     uint64_t val = 0;
158     MemTxResult result;
159 
160     /* Handle some SCOMs here before dispatch */
161     val = xscom_read_default(chip, pcba);
162     if (val != -1) {
163         goto complete;
164     }
165 
166     val = address_space_ldq(&chip->xscom_as, (uint64_t) pcba << 3,
167                             MEMTXATTRS_UNSPECIFIED, &result);
168     if (result != MEMTX_OK) {
169         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM read failed at @0x%"
170                       HWADDR_PRIx " pcba=0x%08x\n", addr, pcba);
171         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
172         return 0;
173     }
174 
175 complete:
176     xscom_complete(current_cpu, HMER_XSCOM_DONE);
177     return val;
178 }
179 
180 static void xscom_write(void *opaque, hwaddr addr, uint64_t val,
181                         unsigned width)
182 {
183     PnvChip *chip = opaque;
184     uint32_t pcba = pnv_xscom_pcba(chip, addr);
185     MemTxResult result;
186 
187     /* Handle some SCOMs here before dispatch */
188     if (xscom_write_default(chip, pcba, val)) {
189         goto complete;
190     }
191 
192     address_space_stq(&chip->xscom_as, (uint64_t) pcba << 3, val,
193                       MEMTXATTRS_UNSPECIFIED, &result);
194     if (result != MEMTX_OK) {
195         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM write failed at @0x%"
196                       HWADDR_PRIx " pcba=0x%08x data=0x%" PRIx64 "\n",
197                       addr, pcba, val);
198         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
199         return;
200     }
201 
202 complete:
203     xscom_complete(current_cpu, HMER_XSCOM_DONE);
204 }
205 
206 const MemoryRegionOps pnv_xscom_ops = {
207     .read = xscom_read,
208     .write = xscom_write,
209     .valid.min_access_size = 8,
210     .valid.max_access_size = 8,
211     .impl.min_access_size = 8,
212     .impl.max_access_size = 8,
213     .endianness = DEVICE_BIG_ENDIAN,
214 };
215 
216 void pnv_xscom_realize(PnvChip *chip, Error **errp)
217 {
218     SysBusDevice *sbd = SYS_BUS_DEVICE(chip);
219     char *name;
220 
221     name = g_strdup_printf("xscom-%x", chip->chip_id);
222     memory_region_init_io(&chip->xscom_mmio, OBJECT(chip), &pnv_xscom_ops,
223                           chip, name, PNV_XSCOM_SIZE);
224     sysbus_init_mmio(sbd, &chip->xscom_mmio);
225 
226     memory_region_init(&chip->xscom, OBJECT(chip), name, PNV_XSCOM_SIZE);
227     address_space_init(&chip->xscom_as, &chip->xscom, name);
228     g_free(name);
229 }
230 
231 static const TypeInfo pnv_xscom_interface_info = {
232     .name = TYPE_PNV_XSCOM_INTERFACE,
233     .parent = TYPE_INTERFACE,
234     .class_size = sizeof(PnvXScomInterfaceClass),
235 };
236 
237 static void pnv_xscom_register_types(void)
238 {
239     type_register_static(&pnv_xscom_interface_info);
240 }
241 
242 type_init(pnv_xscom_register_types)
243 
244 typedef struct ForeachPopulateArgs {
245     void *fdt;
246     int xscom_offset;
247 } ForeachPopulateArgs;
248 
249 static int xscom_dt_child(Object *child, void *opaque)
250 {
251     if (object_dynamic_cast(child, TYPE_PNV_XSCOM_INTERFACE)) {
252         ForeachPopulateArgs *args = opaque;
253         PnvXScomInterface *xd = PNV_XSCOM_INTERFACE(child);
254         PnvXScomInterfaceClass *xc = PNV_XSCOM_INTERFACE_GET_CLASS(xd);
255 
256         if (xc->dt_xscom) {
257             _FDT((xc->dt_xscom(xd, args->fdt, args->xscom_offset)));
258         }
259     }
260     return 0;
261 }
262 
263 static const char compat_p8[] = "ibm,power8-xscom\0ibm,xscom";
264 static const char compat_p9[] = "ibm,power9-xscom\0ibm,xscom";
265 
266 int pnv_dt_xscom(PnvChip *chip, void *fdt, int root_offset)
267 {
268     uint64_t reg[] = { cpu_to_be64(PNV_XSCOM_BASE(chip)),
269                        cpu_to_be64(PNV_XSCOM_SIZE) };
270     int xscom_offset;
271     ForeachPopulateArgs args;
272     char *name;
273 
274     name = g_strdup_printf("xscom@%" PRIx64, be64_to_cpu(reg[0]));
275     xscom_offset = fdt_add_subnode(fdt, root_offset, name);
276     _FDT(xscom_offset);
277     g_free(name);
278     _FDT((fdt_setprop_cell(fdt, xscom_offset, "ibm,chip-id", chip->chip_id)));
279     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#address-cells", 1)));
280     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#size-cells", 1)));
281     _FDT((fdt_setprop(fdt, xscom_offset, "reg", reg, sizeof(reg))));
282 
283     if (pnv_chip_is_power9(chip)) {
284         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p9,
285                           sizeof(compat_p9))));
286     } else {
287         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p8,
288                           sizeof(compat_p8))));
289     }
290 
291     _FDT((fdt_setprop(fdt, xscom_offset, "scom-controller", NULL, 0)));
292 
293     args.fdt = fdt;
294     args.xscom_offset = xscom_offset;
295 
296     object_child_foreach(OBJECT(chip), xscom_dt_child, &args);
297     return 0;
298 }
299 
300 void pnv_xscom_add_subregion(PnvChip *chip, hwaddr offset, MemoryRegion *mr)
301 {
302     memory_region_add_subregion(&chip->xscom, offset << 3, mr);
303 }
304 
305 void pnv_xscom_region_init(MemoryRegion *mr,
306                            struct Object *owner,
307                            const MemoryRegionOps *ops,
308                            void *opaque,
309                            const char *name,
310                            uint64_t size)
311 {
312     memory_region_init_io(mr, owner, ops, opaque, name, size << 3);
313 }
314