xref: /openbmc/qemu/hw/ppc/spapr_rtas_ddw.c (revision 6c187695)
1 /*
2  * QEMU sPAPR Dynamic DMA windows support
3  *
4  * Copyright (c) 2015 Alexey Kardashevskiy, IBM Corporation.
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License,
9  *  or (at your option) any later version.
10  *
11  *  This program 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
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "qemu/error-report.h"
22 #include "qemu/module.h"
23 #include "hw/ppc/spapr.h"
24 #include "hw/pci-host/spapr.h"
25 #include "trace.h"
26 
27 static int spapr_phb_get_active_win_num_cb(Object *child, void *opaque)
28 {
29     SpaprTceTable *tcet;
30 
31     tcet = (SpaprTceTable *) object_dynamic_cast(child, TYPE_SPAPR_TCE_TABLE);
32     if (tcet && tcet->nb_table) {
33         ++*(unsigned *)opaque;
34     }
35     return 0;
36 }
37 
38 static unsigned spapr_phb_get_active_win_num(SpaprPhbState *sphb)
39 {
40     unsigned ret = 0;
41 
42     object_child_foreach(OBJECT(sphb), spapr_phb_get_active_win_num_cb, &ret);
43 
44     return ret;
45 }
46 
47 static int spapr_phb_get_free_liobn_cb(Object *child, void *opaque)
48 {
49     SpaprTceTable *tcet;
50 
51     tcet = (SpaprTceTable *) object_dynamic_cast(child, TYPE_SPAPR_TCE_TABLE);
52     if (tcet && !tcet->nb_table) {
53         *(uint32_t *)opaque = tcet->liobn;
54         return 1;
55     }
56     return 0;
57 }
58 
59 static unsigned spapr_phb_get_free_liobn(SpaprPhbState *sphb)
60 {
61     uint32_t liobn = 0;
62 
63     object_child_foreach(OBJECT(sphb), spapr_phb_get_free_liobn_cb, &liobn);
64 
65     return liobn;
66 }
67 
68 static uint32_t spapr_page_mask_to_query_mask(uint64_t page_mask)
69 {
70     int i;
71     uint32_t mask = 0;
72     const struct { int shift; uint32_t mask; } masks[] = {
73         { 12, RTAS_DDW_PGSIZE_4K },
74         { 16, RTAS_DDW_PGSIZE_64K },
75         { 21, RTAS_DDW_PGSIZE_2M },
76         { 24, RTAS_DDW_PGSIZE_16M },
77         { 25, RTAS_DDW_PGSIZE_32M },
78         { 26, RTAS_DDW_PGSIZE_64M },
79         { 27, RTAS_DDW_PGSIZE_128M },
80         { 28, RTAS_DDW_PGSIZE_256M },
81         { 34, RTAS_DDW_PGSIZE_16G },
82     };
83 
84     for (i = 0; i < ARRAY_SIZE(masks); ++i) {
85         if (page_mask & (1ULL << masks[i].shift)) {
86             mask |= masks[i].mask;
87         }
88     }
89 
90     return mask;
91 }
92 
93 static void rtas_ibm_query_pe_dma_window(PowerPCCPU *cpu,
94                                          SpaprMachineState *spapr,
95                                          uint32_t token, uint32_t nargs,
96                                          target_ulong args,
97                                          uint32_t nret, target_ulong rets)
98 {
99     SpaprPhbState *sphb;
100     uint64_t buid;
101     uint32_t avail, addr, pgmask = 0;
102 
103     if ((nargs != 3) || ((nret != 5) && (nret != 6))) {
104         goto param_error_exit;
105     }
106 
107     buid = ((uint64_t)rtas_ld(args, 1) << 32) | rtas_ld(args, 2);
108     addr = rtas_ld(args, 0);
109     sphb = spapr_pci_find_phb(spapr, buid);
110     if (!sphb || !sphb->ddw_enabled) {
111         goto param_error_exit;
112     }
113 
114     /* Translate page mask to LoPAPR format */
115     pgmask = spapr_page_mask_to_query_mask(sphb->page_size_mask);
116 
117     avail = SPAPR_PCI_DMA_MAX_WINDOWS - spapr_phb_get_active_win_num(sphb);
118 
119     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
120     rtas_st(rets, 1, avail);
121     if (nret == 6) {
122         /*
123          * Set the Max TCE number as 1<<(58-21) = 0x20.0000.0000
124          * 1<<59 is the huge window start and 21 is 2M page shift.
125          */
126         rtas_st(rets, 2, 0x00000020);
127         rtas_st(rets, 3, 0x00000000);
128         rtas_st(rets, 4, pgmask);
129         rtas_st(rets, 5, 0); /* DMA migration mask, not supported */
130     } else {
131         rtas_st(rets, 2, 0x80000000);
132         rtas_st(rets, 3, pgmask);
133         rtas_st(rets, 4, 0); /* DMA migration mask, not supported */
134     }
135 
136     trace_spapr_iommu_ddw_query(buid, addr, avail, 0x80000000, pgmask);
137     return;
138 
139 param_error_exit:
140     rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
141 }
142 
143 static void rtas_ibm_create_pe_dma_window(PowerPCCPU *cpu,
144                                           SpaprMachineState *spapr,
145                                           uint32_t token, uint32_t nargs,
146                                           target_ulong args,
147                                           uint32_t nret, target_ulong rets)
148 {
149     SpaprPhbState *sphb;
150     SpaprTceTable *tcet = NULL;
151     uint32_t addr, page_shift, window_shift, liobn;
152     uint64_t buid, win_addr;
153     int windows;
154 
155     if ((nargs != 5) || (nret != 4)) {
156         goto param_error_exit;
157     }
158 
159     buid = ((uint64_t)rtas_ld(args, 1) << 32) | rtas_ld(args, 2);
160     addr = rtas_ld(args, 0);
161     sphb = spapr_pci_find_phb(spapr, buid);
162     if (!sphb || !sphb->ddw_enabled) {
163         goto param_error_exit;
164     }
165 
166     page_shift = rtas_ld(args, 3);
167     window_shift = rtas_ld(args, 4);
168     liobn = spapr_phb_get_free_liobn(sphb);
169     windows = spapr_phb_get_active_win_num(sphb);
170 
171     if (!(sphb->page_size_mask & (1ULL << page_shift)) ||
172         (window_shift < page_shift)) {
173         goto param_error_exit;
174     }
175 
176     if (!liobn || !sphb->ddw_enabled || windows == SPAPR_PCI_DMA_MAX_WINDOWS) {
177         goto hw_error_exit;
178     }
179 
180     tcet = spapr_tce_find_by_liobn(liobn);
181     if (!tcet) {
182         goto hw_error_exit;
183     }
184 
185     win_addr = (windows == 0) ? sphb->dma_win_addr : sphb->dma64_win_addr;
186     /*
187      * We have just created a window, we know for the fact that it is empty,
188      * use a hack to avoid iterating over the table as it is quite possible
189      * to have billions of TCEs, all empty.
190      * Note that we cannot delay this to the first H_PUT_TCE as this hcall is
191      * mostly likely to be handled in KVM so QEMU just does not know if it
192      * happened.
193      */
194     tcet->skipping_replay = true;
195     spapr_tce_table_enable(tcet, page_shift, win_addr,
196                            1ULL << (window_shift - page_shift));
197     tcet->skipping_replay = false;
198     if (!tcet->nb_table) {
199         goto hw_error_exit;
200     }
201 
202     trace_spapr_iommu_ddw_create(buid, addr, 1ULL << page_shift,
203                                  1ULL << window_shift, tcet->bus_offset, liobn);
204 
205     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
206     rtas_st(rets, 1, liobn);
207     rtas_st(rets, 2, tcet->bus_offset >> 32);
208     rtas_st(rets, 3, tcet->bus_offset & ((uint32_t) -1));
209 
210     return;
211 
212 hw_error_exit:
213     rtas_st(rets, 0, RTAS_OUT_HW_ERROR);
214     return;
215 
216 param_error_exit:
217     rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
218 }
219 
220 static void rtas_ibm_remove_pe_dma_window(PowerPCCPU *cpu,
221                                           SpaprMachineState *spapr,
222                                           uint32_t token, uint32_t nargs,
223                                           target_ulong args,
224                                           uint32_t nret, target_ulong rets)
225 {
226     SpaprPhbState *sphb;
227     SpaprTceTable *tcet;
228     uint32_t liobn;
229     bool def_win_removed;
230 
231     if ((nargs != 1) || (nret != 1)) {
232         goto param_error_exit;
233     }
234 
235     liobn = rtas_ld(args, 0);
236     tcet = spapr_tce_find_by_liobn(liobn);
237     if (!tcet) {
238         goto param_error_exit;
239     }
240 
241     sphb = SPAPR_PCI_HOST_BRIDGE(OBJECT(tcet)->parent);
242     if (!sphb || !sphb->ddw_enabled || !tcet->nb_table) {
243         goto param_error_exit;
244     }
245 
246     def_win_removed = tcet->def_win;
247     spapr_tce_table_disable(tcet);
248     trace_spapr_iommu_ddw_remove(liobn);
249 
250     /*
251      * PAPR+/LoPAPR says:
252      * The platform must restore the default DMA window for the PE on a call
253      * to the ibm,remove-pe-dma-window RTAS call when all of the following
254      * are true:
255      * a. The call removes the last DMA window remaining for the PE.
256      * b. The DMA window being removed is not the default window
257      */
258     if (spapr_phb_get_active_win_num(sphb) == 0 && !def_win_removed) {
259         spapr_phb_dma_reset(sphb);
260         trace_spapr_iommu_ddw_reset(sphb->buid, 0);
261     }
262 
263     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
264     return;
265 
266 param_error_exit:
267     rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
268 }
269 
270 static void rtas_ibm_reset_pe_dma_window(PowerPCCPU *cpu,
271                                          SpaprMachineState *spapr,
272                                          uint32_t token, uint32_t nargs,
273                                          target_ulong args,
274                                          uint32_t nret, target_ulong rets)
275 {
276     SpaprPhbState *sphb;
277     uint64_t buid;
278     uint32_t addr;
279 
280     if ((nargs != 3) || (nret != 1)) {
281         goto param_error_exit;
282     }
283 
284     buid = ((uint64_t)rtas_ld(args, 1) << 32) | rtas_ld(args, 2);
285     addr = rtas_ld(args, 0);
286     sphb = spapr_pci_find_phb(spapr, buid);
287     if (!sphb || !sphb->ddw_enabled) {
288         goto param_error_exit;
289     }
290 
291     spapr_phb_dma_reset(sphb);
292     trace_spapr_iommu_ddw_reset(buid, addr);
293 
294     rtas_st(rets, 0, RTAS_OUT_SUCCESS);
295 
296     return;
297 
298 param_error_exit:
299     rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
300 }
301 
302 static void spapr_rtas_ddw_init(void)
303 {
304     spapr_rtas_register(RTAS_IBM_QUERY_PE_DMA_WINDOW,
305                         "ibm,query-pe-dma-window",
306                         rtas_ibm_query_pe_dma_window);
307     spapr_rtas_register(RTAS_IBM_CREATE_PE_DMA_WINDOW,
308                         "ibm,create-pe-dma-window",
309                         rtas_ibm_create_pe_dma_window);
310     spapr_rtas_register(RTAS_IBM_REMOVE_PE_DMA_WINDOW,
311                         "ibm,remove-pe-dma-window",
312                         rtas_ibm_remove_pe_dma_window);
313     spapr_rtas_register(RTAS_IBM_RESET_PE_DMA_WINDOW,
314                         "ibm,reset-pe-dma-window",
315                         rtas_ibm_reset_pe_dma_window);
316 }
317 
318 type_init(spapr_rtas_ddw_init)
319