xref: /openbmc/qemu/hw/acpi/cxl.c (revision c5c0fdbe)
1 /*
2  * CXL ACPI Implementation
3  *
4  * Copyright(C) 2020 Intel 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/sysbus.h"
22 #include "hw/pci/pci_bridge.h"
23 #include "hw/pci/pci_host.h"
24 #include "hw/cxl/cxl.h"
25 #include "hw/mem/memory-device.h"
26 #include "hw/acpi/acpi.h"
27 #include "hw/acpi/aml-build.h"
28 #include "hw/acpi/bios-linker-loader.h"
29 #include "hw/acpi/cxl.h"
30 #include "qapi/error.h"
31 #include "qemu/uuid.h"
32 
33 static void cedt_build_chbs(GArray *table_data, PXBCXLDev *cxl)
34 {
35     PXBDev *pxb = PXB_DEV(cxl);
36     SysBusDevice *sbd = SYS_BUS_DEVICE(cxl->cxl_host_bridge);
37     struct MemoryRegion *mr = sbd->mmio[0].memory;
38 
39     /* Type */
40     build_append_int_noprefix(table_data, 0, 1);
41 
42     /* Reserved */
43     build_append_int_noprefix(table_data, 0, 1);
44 
45     /* Record Length */
46     build_append_int_noprefix(table_data, 32, 2);
47 
48     /* UID - currently equal to bus number */
49     build_append_int_noprefix(table_data, pxb->bus_nr, 4);
50 
51     /* Version */
52     build_append_int_noprefix(table_data, 1, 4);
53 
54     /* Reserved */
55     build_append_int_noprefix(table_data, 0, 4);
56 
57     /* Base - subregion within a container that is in PA space */
58     build_append_int_noprefix(table_data, mr->container->addr + mr->addr, 8);
59 
60     /* Length */
61     build_append_int_noprefix(table_data, memory_region_size(mr), 8);
62 }
63 
64 /*
65  * CFMWS entries in CXL 2.0 ECN: CEDT CFMWS & QTG _DSM.
66  * Interleave ways encoding in CXL 2.0 ECN: 3, 6, 12 and 16-way memory
67  * interleaving.
68  */
69 static void cedt_build_cfmws(GArray *table_data, CXLState *cxls)
70 {
71     GList *it;
72 
73     for (it = cxls->fixed_windows; it; it = it->next) {
74         CXLFixedWindow *fw = it->data;
75         int i;
76 
77         /* Type */
78         build_append_int_noprefix(table_data, 1, 1);
79 
80         /* Reserved */
81         build_append_int_noprefix(table_data, 0, 1);
82 
83         /* Record Length */
84         build_append_int_noprefix(table_data, 36 + 4 * fw->num_targets, 2);
85 
86         /* Reserved */
87         build_append_int_noprefix(table_data, 0, 4);
88 
89         /* Base HPA */
90         build_append_int_noprefix(table_data, fw->mr.addr, 8);
91 
92         /* Window Size */
93         build_append_int_noprefix(table_data, fw->size, 8);
94 
95         /* Host Bridge Interleave Ways */
96         build_append_int_noprefix(table_data, fw->enc_int_ways, 1);
97 
98         /* Host Bridge Interleave Arithmetic */
99         build_append_int_noprefix(table_data, 0, 1);
100 
101         /* Reserved */
102         build_append_int_noprefix(table_data, 0, 2);
103 
104         /* Host Bridge Interleave Granularity */
105         build_append_int_noprefix(table_data, fw->enc_int_gran, 4);
106 
107         /* Window Restrictions */
108         build_append_int_noprefix(table_data, 0x0f, 2); /* No restrictions */
109 
110         /* QTG ID */
111         build_append_int_noprefix(table_data, 0, 2);
112 
113         /* Host Bridge List (list of UIDs - currently bus_nr) */
114         for (i = 0; i < fw->num_targets; i++) {
115             g_assert(fw->target_hbs[i]);
116             build_append_int_noprefix(table_data, PXB_DEV(fw->target_hbs[i])->bus_nr, 4);
117         }
118     }
119 }
120 
121 static int cxl_foreach_pxb_hb(Object *obj, void *opaque)
122 {
123     Aml *cedt = opaque;
124 
125     if (object_dynamic_cast(obj, TYPE_PXB_CXL_DEV)) {
126         cedt_build_chbs(cedt->buf, PXB_CXL_DEV(obj));
127     }
128 
129     return 0;
130 }
131 
132 void cxl_build_cedt(GArray *table_offsets, GArray *table_data,
133                     BIOSLinker *linker, const char *oem_id,
134                     const char *oem_table_id, CXLState *cxl_state)
135 {
136     Aml *cedt;
137     AcpiTable table = { .sig = "CEDT", .rev = 1, .oem_id = oem_id,
138                         .oem_table_id = oem_table_id };
139 
140     acpi_add_table(table_offsets, table_data);
141     acpi_table_begin(&table, table_data);
142     cedt = init_aml_allocator();
143 
144     /* reserve space for CEDT header */
145 
146     object_child_foreach_recursive(object_get_root(), cxl_foreach_pxb_hb, cedt);
147     cedt_build_cfmws(cedt->buf, cxl_state);
148 
149     /* copy AML table into ACPI tables blob and patch header there */
150     g_array_append_vals(table_data, cedt->buf->data, cedt->buf->len);
151     free_aml_allocator();
152 
153     acpi_table_end(linker, &table);
154 }
155 
156 static Aml *__build_cxl_osc_method(void)
157 {
158     Aml *method, *if_uuid, *else_uuid, *if_arg1_not_1, *if_cxl, *if_caps_masked;
159     Aml *a_ctrl = aml_local(0);
160     Aml *a_cdw1 = aml_name("CDW1");
161 
162     method = aml_method("_OSC", 4, AML_NOTSERIALIZED);
163     /* CDW1 is used for the return value so is present whether or not a match occurs */
164     aml_append(method, aml_create_dword_field(aml_arg(3), aml_int(0), "CDW1"));
165 
166     /*
167      * Generate shared section between:
168      * CXL 2.0 - 9.14.2.1.4 and
169      * PCI Firmware Specification 3.0
170      * 4.5.1. _OSC Interface for PCI Host Bridge Devices
171      * The _OSC interface for a PCI/PCI-X/PCI Express hierarchy is
172      * identified by the Universal Unique IDentifier (UUID)
173      * 33DB4D5B-1FF7-401C-9657-7441C03DD766
174      * The _OSC interface for a CXL Host bridge is
175      * identified by the UUID 68F2D50B-C469-4D8A-BD3D-941A103FD3FC
176      * A CXL Host bridge is compatible with a PCI host bridge so
177      * for the shared section match both.
178      */
179     if_uuid = aml_if(
180         aml_lor(aml_equal(aml_arg(0),
181                           aml_touuid("33DB4D5B-1FF7-401C-9657-7441C03DD766")),
182                 aml_equal(aml_arg(0),
183                           aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC"))));
184     aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(4), "CDW2"));
185     aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(8), "CDW3"));
186 
187     aml_append(if_uuid, aml_store(aml_name("CDW3"), a_ctrl));
188 
189     /*
190      *
191      * Allows OS control for all 5 features:
192      * PCIeHotplug SHPCHotplug PME AER PCIeCapability
193      */
194     aml_append(if_uuid, aml_and(a_ctrl, aml_int(0x1F), a_ctrl));
195 
196     /*
197      * Check _OSC revision.
198      * PCI Firmware specification 3.3 and CXL 2.0 both use revision 1
199      * Unknown Revision is CDW1 - BIT (3)
200      */
201     if_arg1_not_1 = aml_if(aml_lnot(aml_equal(aml_arg(1), aml_int(0x1))));
202     aml_append(if_arg1_not_1, aml_or(a_cdw1, aml_int(0x08), a_cdw1));
203     aml_append(if_uuid, if_arg1_not_1);
204 
205     if_caps_masked = aml_if(aml_lnot(aml_equal(aml_name("CDW3"), a_ctrl)));
206 
207     /* Capability bits were masked */
208     aml_append(if_caps_masked, aml_or(a_cdw1, aml_int(0x10), a_cdw1));
209     aml_append(if_uuid, if_caps_masked);
210 
211     aml_append(if_uuid, aml_store(aml_name("CDW2"), aml_name("SUPP")));
212     aml_append(if_uuid, aml_store(aml_name("CDW3"), aml_name("CTRL")));
213 
214     /* Update DWORD3 (the return value) */
215     aml_append(if_uuid, aml_store(a_ctrl, aml_name("CDW3")));
216 
217     /* CXL only section as per CXL 2.0 - 9.14.2.1.4 */
218     if_cxl = aml_if(aml_equal(
219         aml_arg(0), aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC")));
220     /* CXL support field */
221     aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(12), "CDW4"));
222     /* CXL capabilities */
223     aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(16), "CDW5"));
224     aml_append(if_cxl, aml_store(aml_name("CDW4"), aml_name("SUPC")));
225     aml_append(if_cxl, aml_store(aml_name("CDW5"), aml_name("CTRC")));
226 
227     /* CXL 2.0 Port/Device Register access */
228     aml_append(if_cxl,
229                aml_or(aml_name("CDW5"), aml_int(0x1), aml_name("CDW5")));
230     aml_append(if_uuid, if_cxl);
231 
232     aml_append(if_uuid, aml_return(aml_arg(3)));
233     aml_append(method, if_uuid);
234 
235     /*
236      * If no UUID matched, return Unrecognized UUID via Arg3 DWord 1
237      * ACPI 6.4 - 6.2.11
238      * Unrecognised UUID - BIT(2)
239      */
240     else_uuid = aml_else();
241 
242     aml_append(else_uuid,
243                aml_or(aml_name("CDW1"), aml_int(0x4), aml_name("CDW1")));
244     aml_append(else_uuid, aml_return(aml_arg(3)));
245     aml_append(method, else_uuid);
246 
247     return method;
248 }
249 
250 void build_cxl_osc_method(Aml *dev)
251 {
252     aml_append(dev, aml_name_decl("SUPP", aml_int(0)));
253     aml_append(dev, aml_name_decl("CTRL", aml_int(0)));
254     aml_append(dev, aml_name_decl("SUPC", aml_int(0)));
255     aml_append(dev, aml_name_decl("CTRC", aml_int(0)));
256     aml_append(dev, __build_cxl_osc_method());
257 }
258