xref: /openbmc/qemu/hw/ppc/pnv_xscom.c (revision 4fe6d78b)
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 "qapi/error.h"
21 #include "hw/hw.h"
22 #include "qemu/log.h"
23 #include "sysemu/hw_accel.h"
24 #include "target/ppc/cpu.h"
25 #include "hw/sysbus.h"
26 
27 #include "hw/ppc/fdt.h"
28 #include "hw/ppc/pnv.h"
29 #include "hw/ppc/pnv_xscom.h"
30 
31 #include <libfdt.h>
32 
33 static void xscom_complete(CPUState *cs, uint64_t hmer_bits)
34 {
35     /*
36      * TODO: When the read/write comes from the monitor, NULL is
37      * passed for the cpu, and no CPU completion is generated.
38      */
39     if (cs) {
40         PowerPCCPU *cpu = POWERPC_CPU(cs);
41         CPUPPCState *env = &cpu->env;
42 
43         /*
44          * TODO: Need a CPU helper to set HMER, also handle generation
45          * of HMIs
46          */
47         cpu_synchronize_state(cs);
48         env->spr[SPR_HMER] |= hmer_bits;
49     }
50 }
51 
52 static uint32_t pnv_xscom_pcba(PnvChip *chip, uint64_t addr)
53 {
54     addr &= (PNV_XSCOM_SIZE - 1);
55 
56     if (pnv_chip_is_power9(chip)) {
57         return addr >> 3;
58     } else {
59         return ((addr >> 4) & ~0xfull) | ((addr >> 3) & 0xf);
60     }
61 }
62 
63 static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
64 {
65     switch (pcba) {
66     case 0xf000f:
67         return PNV_CHIP_GET_CLASS(chip)->chip_cfam_id;
68     case 0x1010c00:     /* PIBAM FIR */
69     case 0x1010c03:     /* PIBAM FIR MASK */
70     case 0x2020007:     /* ADU stuff */
71     case 0x2020009:     /* ADU stuff */
72     case 0x202000f:     /* ADU stuff */
73         return 0;
74     case 0x2013f00:     /* PBA stuff */
75     case 0x2013f01:     /* PBA stuff */
76     case 0x2013f02:     /* PBA stuff */
77     case 0x2013f03:     /* PBA stuff */
78     case 0x2013f04:     /* PBA stuff */
79     case 0x2013f05:     /* PBA stuff */
80     case 0x2013f06:     /* PBA stuff */
81     case 0x2013f07:     /* PBA stuff */
82         return 0;
83     case 0x2013028:     /* CAPP stuff */
84     case 0x201302a:     /* CAPP stuff */
85     case 0x2013801:     /* CAPP stuff */
86     case 0x2013802:     /* CAPP stuff */
87         return 0;
88     default:
89         return -1;
90     }
91 }
92 
93 static bool xscom_write_default(PnvChip *chip, uint32_t pcba, uint64_t val)
94 {
95     /* We ignore writes to these */
96     switch (pcba) {
97     case 0xf000f:       /* chip id is RO */
98     case 0x1010c00:     /* PIBAM FIR */
99     case 0x1010c01:     /* PIBAM FIR */
100     case 0x1010c02:     /* PIBAM FIR */
101     case 0x1010c03:     /* PIBAM FIR MASK */
102     case 0x1010c04:     /* PIBAM FIR MASK */
103     case 0x1010c05:     /* PIBAM FIR MASK */
104     case 0x2020007:     /* ADU stuff */
105     case 0x2020009:     /* ADU stuff */
106     case 0x202000f:     /* ADU stuff */
107         return true;
108     default:
109         return false;
110     }
111 }
112 
113 static uint64_t xscom_read(void *opaque, hwaddr addr, unsigned width)
114 {
115     PnvChip *chip = opaque;
116     uint32_t pcba = pnv_xscom_pcba(chip, addr);
117     uint64_t val = 0;
118     MemTxResult result;
119 
120     /* Handle some SCOMs here before dispatch */
121     val = xscom_read_default(chip, pcba);
122     if (val != -1) {
123         goto complete;
124     }
125 
126     val = address_space_ldq(&chip->xscom_as, (uint64_t) pcba << 3,
127                             MEMTXATTRS_UNSPECIFIED, &result);
128     if (result != MEMTX_OK) {
129         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM read failed at @0x%"
130                       HWADDR_PRIx " pcba=0x%08x\n", addr, pcba);
131         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
132         return 0;
133     }
134 
135 complete:
136     xscom_complete(current_cpu, HMER_XSCOM_DONE);
137     return val;
138 }
139 
140 static void xscom_write(void *opaque, hwaddr addr, uint64_t val,
141                         unsigned width)
142 {
143     PnvChip *chip = opaque;
144     uint32_t pcba = pnv_xscom_pcba(chip, addr);
145     MemTxResult result;
146 
147     /* Handle some SCOMs here before dispatch */
148     if (xscom_write_default(chip, pcba, val)) {
149         goto complete;
150     }
151 
152     address_space_stq(&chip->xscom_as, (uint64_t) pcba << 3, val,
153                       MEMTXATTRS_UNSPECIFIED, &result);
154     if (result != MEMTX_OK) {
155         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM write failed at @0x%"
156                       HWADDR_PRIx " pcba=0x%08x data=0x%" PRIx64 "\n",
157                       addr, pcba, val);
158         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
159         return;
160     }
161 
162 complete:
163     xscom_complete(current_cpu, HMER_XSCOM_DONE);
164 }
165 
166 const MemoryRegionOps pnv_xscom_ops = {
167     .read = xscom_read,
168     .write = xscom_write,
169     .valid.min_access_size = 8,
170     .valid.max_access_size = 8,
171     .impl.min_access_size = 8,
172     .impl.max_access_size = 8,
173     .endianness = DEVICE_BIG_ENDIAN,
174 };
175 
176 void pnv_xscom_realize(PnvChip *chip, Error **errp)
177 {
178     SysBusDevice *sbd = SYS_BUS_DEVICE(chip);
179     char *name;
180 
181     name = g_strdup_printf("xscom-%x", chip->chip_id);
182     memory_region_init_io(&chip->xscom_mmio, OBJECT(chip), &pnv_xscom_ops,
183                           chip, name, PNV_XSCOM_SIZE);
184     sysbus_init_mmio(sbd, &chip->xscom_mmio);
185 
186     memory_region_init(&chip->xscom, OBJECT(chip), name, PNV_XSCOM_SIZE);
187     address_space_init(&chip->xscom_as, &chip->xscom, name);
188     g_free(name);
189 }
190 
191 static const TypeInfo pnv_xscom_interface_info = {
192     .name = TYPE_PNV_XSCOM_INTERFACE,
193     .parent = TYPE_INTERFACE,
194     .class_size = sizeof(PnvXScomInterfaceClass),
195 };
196 
197 static void pnv_xscom_register_types(void)
198 {
199     type_register_static(&pnv_xscom_interface_info);
200 }
201 
202 type_init(pnv_xscom_register_types)
203 
204 typedef struct ForeachPopulateArgs {
205     void *fdt;
206     int xscom_offset;
207 } ForeachPopulateArgs;
208 
209 static int xscom_dt_child(Object *child, void *opaque)
210 {
211     if (object_dynamic_cast(child, TYPE_PNV_XSCOM_INTERFACE)) {
212         ForeachPopulateArgs *args = opaque;
213         PnvXScomInterface *xd = PNV_XSCOM_INTERFACE(child);
214         PnvXScomInterfaceClass *xc = PNV_XSCOM_INTERFACE_GET_CLASS(xd);
215 
216         if (xc->dt_xscom) {
217             _FDT((xc->dt_xscom(xd, args->fdt, args->xscom_offset)));
218         }
219     }
220     return 0;
221 }
222 
223 static const char compat_p8[] = "ibm,power8-xscom\0ibm,xscom";
224 static const char compat_p9[] = "ibm,power9-xscom\0ibm,xscom";
225 
226 int pnv_dt_xscom(PnvChip *chip, void *fdt, int root_offset)
227 {
228     uint64_t reg[] = { cpu_to_be64(PNV_XSCOM_BASE(chip)),
229                        cpu_to_be64(PNV_XSCOM_SIZE) };
230     int xscom_offset;
231     ForeachPopulateArgs args;
232     char *name;
233 
234     name = g_strdup_printf("xscom@%" PRIx64, be64_to_cpu(reg[0]));
235     xscom_offset = fdt_add_subnode(fdt, root_offset, name);
236     _FDT(xscom_offset);
237     g_free(name);
238     _FDT((fdt_setprop_cell(fdt, xscom_offset, "ibm,chip-id", chip->chip_id)));
239     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#address-cells", 1)));
240     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#size-cells", 1)));
241     _FDT((fdt_setprop(fdt, xscom_offset, "reg", reg, sizeof(reg))));
242 
243     if (pnv_chip_is_power9(chip)) {
244         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p9,
245                           sizeof(compat_p9))));
246     } else {
247         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p8,
248                           sizeof(compat_p8))));
249     }
250 
251     _FDT((fdt_setprop(fdt, xscom_offset, "scom-controller", NULL, 0)));
252 
253     args.fdt = fdt;
254     args.xscom_offset = xscom_offset;
255 
256     object_child_foreach(OBJECT(chip), xscom_dt_child, &args);
257     return 0;
258 }
259 
260 void pnv_xscom_add_subregion(PnvChip *chip, hwaddr offset, MemoryRegion *mr)
261 {
262     memory_region_add_subregion(&chip->xscom, offset << 3, mr);
263 }
264 
265 void pnv_xscom_region_init(MemoryRegion *mr,
266                            struct Object *owner,
267                            const MemoryRegionOps *ops,
268                            void *opaque,
269                            const char *name,
270                            uint64_t size)
271 {
272     memory_region_init_io(mr, owner, ops, opaque, name, size << 3);
273 }
274