xref: /openbmc/qemu/hw/ppc/pnv_xscom.c (revision 8cf108c5)
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 #include "qemu/osdep.h"
20 #include "hw/hw.h"
21 #include "qemu/log.h"
22 #include "sysemu/hw_accel.h"
23 #include "target/ppc/cpu.h"
24 #include "hw/sysbus.h"
25 
26 #include "hw/ppc/fdt.h"
27 #include "hw/ppc/pnv.h"
28 #include "hw/ppc/pnv_xscom.h"
29 
30 #include <libfdt.h>
31 
32 static void xscom_complete(CPUState *cs, uint64_t hmer_bits)
33 {
34     /*
35      * TODO: When the read/write comes from the monitor, NULL is
36      * passed for the cpu, and no CPU completion is generated.
37      */
38     if (cs) {
39         PowerPCCPU *cpu = POWERPC_CPU(cs);
40         CPUPPCState *env = &cpu->env;
41 
42         /*
43          * TODO: Need a CPU helper to set HMER, also handle generation
44          * of HMIs
45          */
46         cpu_synchronize_state(cs);
47         env->spr[SPR_HMER] |= hmer_bits;
48     }
49 }
50 
51 static uint32_t pnv_xscom_pcba(PnvChip *chip, uint64_t addr)
52 {
53     addr &= (PNV_XSCOM_SIZE - 1);
54 
55     if (pnv_chip_is_power9(chip)) {
56         return addr >> 3;
57     } else {
58         return ((addr >> 4) & ~0xfull) | ((addr >> 3) & 0xf);
59     }
60 }
61 
62 static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
63 {
64     switch (pcba) {
65     case 0xf000f:
66         return PNV_CHIP_GET_CLASS(chip)->chip_cfam_id;
67     case 0x18002:       /* ECID2 */
68         return 0;
69 
70     case 0x1010c00:     /* PIBAM FIR */
71     case 0x1010c03:     /* PIBAM FIR MASK */
72 
73         /* P9 xscom reset */
74     case 0x0090018:     /* Receive status reg */
75     case 0x0090012:     /* log register */
76     case 0x0090013:     /* error register */
77 
78         /* P8 xscom reset */
79     case 0x2020007:     /* ADU stuff, log register */
80     case 0x2020009:     /* ADU stuff, error register */
81     case 0x202000f:     /* ADU stuff, receive status register*/
82         return 0;
83     case 0x2013f00:     /* PBA stuff */
84     case 0x2013f01:     /* PBA stuff */
85     case 0x2013f02:     /* PBA stuff */
86     case 0x2013f03:     /* PBA stuff */
87     case 0x2013f04:     /* PBA stuff */
88     case 0x2013f05:     /* PBA stuff */
89     case 0x2013f06:     /* PBA stuff */
90     case 0x2013f07:     /* PBA stuff */
91         return 0;
92     case 0x2013028:     /* CAPP stuff */
93     case 0x201302a:     /* CAPP stuff */
94     case 0x2013801:     /* CAPP stuff */
95     case 0x2013802:     /* CAPP stuff */
96         return 0;
97     default:
98         return -1;
99     }
100 }
101 
102 static bool xscom_write_default(PnvChip *chip, uint32_t pcba, uint64_t val)
103 {
104     /* We ignore writes to these */
105     switch (pcba) {
106     case 0xf000f:       /* chip id is RO */
107     case 0x1010c00:     /* PIBAM FIR */
108     case 0x1010c01:     /* PIBAM FIR */
109     case 0x1010c02:     /* PIBAM FIR */
110     case 0x1010c03:     /* PIBAM FIR MASK */
111     case 0x1010c04:     /* PIBAM FIR MASK */
112     case 0x1010c05:     /* PIBAM FIR MASK */
113         /* P9 xscom reset */
114     case 0x0090018:     /* Receive status reg */
115     case 0x0090012:     /* log register */
116     case 0x0090013:     /* error register */
117 
118         /* P8 xscom reset */
119     case 0x2020007:     /* ADU stuff, log register */
120     case 0x2020009:     /* ADU stuff, error register */
121     case 0x202000f:     /* ADU stuff, receive status register*/
122 
123     case 0x2013028:     /* CAPP stuff */
124     case 0x201302a:     /* CAPP stuff */
125     case 0x2013801:     /* CAPP stuff */
126     case 0x2013802:     /* CAPP stuff */
127         return true;
128     default:
129         return false;
130     }
131 }
132 
133 static uint64_t xscom_read(void *opaque, hwaddr addr, unsigned width)
134 {
135     PnvChip *chip = opaque;
136     uint32_t pcba = pnv_xscom_pcba(chip, addr);
137     uint64_t val = 0;
138     MemTxResult result;
139 
140     /* Handle some SCOMs here before dispatch */
141     val = xscom_read_default(chip, pcba);
142     if (val != -1) {
143         goto complete;
144     }
145 
146     val = address_space_ldq(&chip->xscom_as, (uint64_t) pcba << 3,
147                             MEMTXATTRS_UNSPECIFIED, &result);
148     if (result != MEMTX_OK) {
149         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM read failed at @0x%"
150                       HWADDR_PRIx " pcba=0x%08x\n", addr, pcba);
151         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
152         return 0;
153     }
154 
155 complete:
156     xscom_complete(current_cpu, HMER_XSCOM_DONE);
157     return val;
158 }
159 
160 static void xscom_write(void *opaque, hwaddr addr, uint64_t val,
161                         unsigned width)
162 {
163     PnvChip *chip = opaque;
164     uint32_t pcba = pnv_xscom_pcba(chip, addr);
165     MemTxResult result;
166 
167     /* Handle some SCOMs here before dispatch */
168     if (xscom_write_default(chip, pcba, val)) {
169         goto complete;
170     }
171 
172     address_space_stq(&chip->xscom_as, (uint64_t) pcba << 3, val,
173                       MEMTXATTRS_UNSPECIFIED, &result);
174     if (result != MEMTX_OK) {
175         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM write failed at @0x%"
176                       HWADDR_PRIx " pcba=0x%08x data=0x%" PRIx64 "\n",
177                       addr, pcba, val);
178         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
179         return;
180     }
181 
182 complete:
183     xscom_complete(current_cpu, HMER_XSCOM_DONE);
184 }
185 
186 const MemoryRegionOps pnv_xscom_ops = {
187     .read = xscom_read,
188     .write = xscom_write,
189     .valid.min_access_size = 8,
190     .valid.max_access_size = 8,
191     .impl.min_access_size = 8,
192     .impl.max_access_size = 8,
193     .endianness = DEVICE_BIG_ENDIAN,
194 };
195 
196 void pnv_xscom_realize(PnvChip *chip, Error **errp)
197 {
198     SysBusDevice *sbd = SYS_BUS_DEVICE(chip);
199     char *name;
200 
201     name = g_strdup_printf("xscom-%x", chip->chip_id);
202     memory_region_init_io(&chip->xscom_mmio, OBJECT(chip), &pnv_xscom_ops,
203                           chip, name, PNV_XSCOM_SIZE);
204     sysbus_init_mmio(sbd, &chip->xscom_mmio);
205 
206     memory_region_init(&chip->xscom, OBJECT(chip), name, PNV_XSCOM_SIZE);
207     address_space_init(&chip->xscom_as, &chip->xscom, name);
208     g_free(name);
209 }
210 
211 static const TypeInfo pnv_xscom_interface_info = {
212     .name = TYPE_PNV_XSCOM_INTERFACE,
213     .parent = TYPE_INTERFACE,
214     .class_size = sizeof(PnvXScomInterfaceClass),
215 };
216 
217 static void pnv_xscom_register_types(void)
218 {
219     type_register_static(&pnv_xscom_interface_info);
220 }
221 
222 type_init(pnv_xscom_register_types)
223 
224 typedef struct ForeachPopulateArgs {
225     void *fdt;
226     int xscom_offset;
227 } ForeachPopulateArgs;
228 
229 static int xscom_dt_child(Object *child, void *opaque)
230 {
231     if (object_dynamic_cast(child, TYPE_PNV_XSCOM_INTERFACE)) {
232         ForeachPopulateArgs *args = opaque;
233         PnvXScomInterface *xd = PNV_XSCOM_INTERFACE(child);
234         PnvXScomInterfaceClass *xc = PNV_XSCOM_INTERFACE_GET_CLASS(xd);
235 
236         if (xc->dt_xscom) {
237             _FDT((xc->dt_xscom(xd, args->fdt, args->xscom_offset)));
238         }
239     }
240     return 0;
241 }
242 
243 static const char compat_p8[] = "ibm,power8-xscom\0ibm,xscom";
244 static const char compat_p9[] = "ibm,power9-xscom\0ibm,xscom";
245 
246 int pnv_dt_xscom(PnvChip *chip, void *fdt, int root_offset)
247 {
248     uint64_t reg[] = { cpu_to_be64(PNV_XSCOM_BASE(chip)),
249                        cpu_to_be64(PNV_XSCOM_SIZE) };
250     int xscom_offset;
251     ForeachPopulateArgs args;
252     char *name;
253 
254     name = g_strdup_printf("xscom@%" PRIx64, be64_to_cpu(reg[0]));
255     xscom_offset = fdt_add_subnode(fdt, root_offset, name);
256     _FDT(xscom_offset);
257     g_free(name);
258     _FDT((fdt_setprop_cell(fdt, xscom_offset, "ibm,chip-id", chip->chip_id)));
259     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#address-cells", 1)));
260     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#size-cells", 1)));
261     _FDT((fdt_setprop(fdt, xscom_offset, "reg", reg, sizeof(reg))));
262 
263     if (pnv_chip_is_power9(chip)) {
264         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p9,
265                           sizeof(compat_p9))));
266     } else {
267         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p8,
268                           sizeof(compat_p8))));
269     }
270 
271     _FDT((fdt_setprop(fdt, xscom_offset, "scom-controller", NULL, 0)));
272 
273     args.fdt = fdt;
274     args.xscom_offset = xscom_offset;
275 
276     object_child_foreach(OBJECT(chip), xscom_dt_child, &args);
277     return 0;
278 }
279 
280 void pnv_xscom_add_subregion(PnvChip *chip, hwaddr offset, MemoryRegion *mr)
281 {
282     memory_region_add_subregion(&chip->xscom, offset << 3, mr);
283 }
284 
285 void pnv_xscom_region_init(MemoryRegion *mr,
286                            struct Object *owner,
287                            const MemoryRegionOps *ops,
288                            void *opaque,
289                            const char *name,
290                            uint64_t size)
291 {
292     memory_region_init_io(mr, owner, ops, opaque, name, size << 3);
293 }
294