xref: /openbmc/qemu/hw/ppc/pnv_xscom.c (revision ba632924)
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 0x1010c00:     /* PIBAM FIR */
68     case 0x1010c03:     /* PIBAM FIR MASK */
69     case 0x2020007:     /* ADU stuff */
70     case 0x2020009:     /* ADU stuff */
71     case 0x202000f:     /* ADU stuff */
72         return 0;
73     case 0x2013f00:     /* PBA stuff */
74     case 0x2013f01:     /* PBA stuff */
75     case 0x2013f02:     /* PBA stuff */
76     case 0x2013f03:     /* PBA stuff */
77     case 0x2013f04:     /* PBA stuff */
78     case 0x2013f05:     /* PBA stuff */
79     case 0x2013f06:     /* PBA stuff */
80     case 0x2013f07:     /* PBA stuff */
81         return 0;
82     case 0x2013028:     /* CAPP stuff */
83     case 0x201302a:     /* CAPP stuff */
84     case 0x2013801:     /* CAPP stuff */
85     case 0x2013802:     /* CAPP stuff */
86         return 0;
87     default:
88         return -1;
89     }
90 }
91 
92 static bool xscom_write_default(PnvChip *chip, uint32_t pcba, uint64_t val)
93 {
94     /* We ignore writes to these */
95     switch (pcba) {
96     case 0xf000f:       /* chip id is RO */
97     case 0x1010c00:     /* PIBAM FIR */
98     case 0x1010c01:     /* PIBAM FIR */
99     case 0x1010c02:     /* PIBAM FIR */
100     case 0x1010c03:     /* PIBAM FIR MASK */
101     case 0x1010c04:     /* PIBAM FIR MASK */
102     case 0x1010c05:     /* PIBAM FIR MASK */
103     case 0x2020007:     /* ADU stuff */
104     case 0x2020009:     /* ADU stuff */
105     case 0x202000f:     /* ADU stuff */
106         return true;
107     default:
108         return false;
109     }
110 }
111 
112 static uint64_t xscom_read(void *opaque, hwaddr addr, unsigned width)
113 {
114     PnvChip *chip = opaque;
115     uint32_t pcba = pnv_xscom_pcba(chip, addr);
116     uint64_t val = 0;
117     MemTxResult result;
118 
119     /* Handle some SCOMs here before dispatch */
120     val = xscom_read_default(chip, pcba);
121     if (val != -1) {
122         goto complete;
123     }
124 
125     val = address_space_ldq(&chip->xscom_as, (uint64_t) pcba << 3,
126                             MEMTXATTRS_UNSPECIFIED, &result);
127     if (result != MEMTX_OK) {
128         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM read failed at @0x%"
129                       HWADDR_PRIx " pcba=0x%08x\n", addr, pcba);
130         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
131         return 0;
132     }
133 
134 complete:
135     xscom_complete(current_cpu, HMER_XSCOM_DONE);
136     return val;
137 }
138 
139 static void xscom_write(void *opaque, hwaddr addr, uint64_t val,
140                         unsigned width)
141 {
142     PnvChip *chip = opaque;
143     uint32_t pcba = pnv_xscom_pcba(chip, addr);
144     MemTxResult result;
145 
146     /* Handle some SCOMs here before dispatch */
147     if (xscom_write_default(chip, pcba, val)) {
148         goto complete;
149     }
150 
151     address_space_stq(&chip->xscom_as, (uint64_t) pcba << 3, val,
152                       MEMTXATTRS_UNSPECIFIED, &result);
153     if (result != MEMTX_OK) {
154         qemu_log_mask(LOG_GUEST_ERROR, "XSCOM write failed at @0x%"
155                       HWADDR_PRIx " pcba=0x%08x data=0x%" PRIx64 "\n",
156                       addr, pcba, val);
157         xscom_complete(current_cpu, HMER_XSCOM_FAIL | HMER_XSCOM_DONE);
158         return;
159     }
160 
161 complete:
162     xscom_complete(current_cpu, HMER_XSCOM_DONE);
163 }
164 
165 const MemoryRegionOps pnv_xscom_ops = {
166     .read = xscom_read,
167     .write = xscom_write,
168     .valid.min_access_size = 8,
169     .valid.max_access_size = 8,
170     .impl.min_access_size = 8,
171     .impl.max_access_size = 8,
172     .endianness = DEVICE_BIG_ENDIAN,
173 };
174 
175 void pnv_xscom_realize(PnvChip *chip, Error **errp)
176 {
177     SysBusDevice *sbd = SYS_BUS_DEVICE(chip);
178     char *name;
179 
180     name = g_strdup_printf("xscom-%x", chip->chip_id);
181     memory_region_init_io(&chip->xscom_mmio, OBJECT(chip), &pnv_xscom_ops,
182                           chip, name, PNV_XSCOM_SIZE);
183     sysbus_init_mmio(sbd, &chip->xscom_mmio);
184 
185     memory_region_init(&chip->xscom, OBJECT(chip), name, PNV_XSCOM_SIZE);
186     address_space_init(&chip->xscom_as, &chip->xscom, name);
187     g_free(name);
188 }
189 
190 static const TypeInfo pnv_xscom_interface_info = {
191     .name = TYPE_PNV_XSCOM_INTERFACE,
192     .parent = TYPE_INTERFACE,
193     .class_size = sizeof(PnvXScomInterfaceClass),
194 };
195 
196 static void pnv_xscom_register_types(void)
197 {
198     type_register_static(&pnv_xscom_interface_info);
199 }
200 
201 type_init(pnv_xscom_register_types)
202 
203 typedef struct ForeachPopulateArgs {
204     void *fdt;
205     int xscom_offset;
206 } ForeachPopulateArgs;
207 
208 static int xscom_dt_child(Object *child, void *opaque)
209 {
210     if (object_dynamic_cast(child, TYPE_PNV_XSCOM_INTERFACE)) {
211         ForeachPopulateArgs *args = opaque;
212         PnvXScomInterface *xd = PNV_XSCOM_INTERFACE(child);
213         PnvXScomInterfaceClass *xc = PNV_XSCOM_INTERFACE_GET_CLASS(xd);
214 
215         if (xc->dt_xscom) {
216             _FDT((xc->dt_xscom(xd, args->fdt, args->xscom_offset)));
217         }
218     }
219     return 0;
220 }
221 
222 static const char compat_p8[] = "ibm,power8-xscom\0ibm,xscom";
223 static const char compat_p9[] = "ibm,power9-xscom\0ibm,xscom";
224 
225 int pnv_dt_xscom(PnvChip *chip, void *fdt, int root_offset)
226 {
227     uint64_t reg[] = { cpu_to_be64(PNV_XSCOM_BASE(chip)),
228                        cpu_to_be64(PNV_XSCOM_SIZE) };
229     int xscom_offset;
230     ForeachPopulateArgs args;
231     char *name;
232 
233     name = g_strdup_printf("xscom@%" PRIx64, be64_to_cpu(reg[0]));
234     xscom_offset = fdt_add_subnode(fdt, root_offset, name);
235     _FDT(xscom_offset);
236     g_free(name);
237     _FDT((fdt_setprop_cell(fdt, xscom_offset, "ibm,chip-id", chip->chip_id)));
238     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#address-cells", 1)));
239     _FDT((fdt_setprop_cell(fdt, xscom_offset, "#size-cells", 1)));
240     _FDT((fdt_setprop(fdt, xscom_offset, "reg", reg, sizeof(reg))));
241 
242     if (pnv_chip_is_power9(chip)) {
243         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p9,
244                           sizeof(compat_p9))));
245     } else {
246         _FDT((fdt_setprop(fdt, xscom_offset, "compatible", compat_p8,
247                           sizeof(compat_p8))));
248     }
249 
250     _FDT((fdt_setprop(fdt, xscom_offset, "scom-controller", NULL, 0)));
251 
252     args.fdt = fdt;
253     args.xscom_offset = xscom_offset;
254 
255     object_child_foreach(OBJECT(chip), xscom_dt_child, &args);
256     return 0;
257 }
258 
259 void pnv_xscom_add_subregion(PnvChip *chip, hwaddr offset, MemoryRegion *mr)
260 {
261     memory_region_add_subregion(&chip->xscom, offset << 3, mr);
262 }
263 
264 void pnv_xscom_region_init(MemoryRegion *mr,
265                            struct Object *owner,
266                            const MemoryRegionOps *ops,
267                            void *opaque,
268                            const char *name,
269                            uint64_t size)
270 {
271     memory_region_init_io(mr, owner, ops, opaque, name, size << 3);
272 }
273