xref: /openbmc/qemu/hw/acpi/cxl.c (revision f085ba29)
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, PXBDev *cxl)
34 {
35     SysBusDevice *sbd = SYS_BUS_DEVICE(cxl->cxl.cxl_host_bridge);
36     struct MemoryRegion *mr = sbd->mmio[0].memory;
37 
38     /* Type */
39     build_append_int_noprefix(table_data, 0, 1);
40 
41     /* Reserved */
42     build_append_int_noprefix(table_data, 0, 1);
43 
44     /* Record Length */
45     build_append_int_noprefix(table_data, 32, 2);
46 
47     /* UID - currently equal to bus number */
48     build_append_int_noprefix(table_data, cxl->bus_nr, 4);
49 
50     /* Version */
51     build_append_int_noprefix(table_data, 1, 4);
52 
53     /* Reserved */
54     build_append_int_noprefix(table_data, 0, 4);
55 
56     /* Base - subregion within a container that is in PA space */
57     build_append_int_noprefix(table_data, mr->container->addr + mr->addr, 8);
58 
59     /* Length */
60     build_append_int_noprefix(table_data, memory_region_size(mr), 8);
61 }
62 
63 /*
64  * CFMWS entries in CXL 2.0 ECN: CEDT CFMWS & QTG _DSM.
65  * Interleave ways encoding in CXL 2.0 ECN: 3, 6, 12 and 16-way memory
66  * interleaving.
67  */
68 static void cedt_build_cfmws(GArray *table_data, CXLState *cxls)
69 {
70     GList *it;
71 
72     for (it = cxls->fixed_windows; it; it = it->next) {
73         CXLFixedWindow *fw = it->data;
74         int i;
75 
76         /* Type */
77         build_append_int_noprefix(table_data, 1, 1);
78 
79         /* Reserved */
80         build_append_int_noprefix(table_data, 0, 1);
81 
82         /* Record Length */
83         build_append_int_noprefix(table_data, 36 + 4 * fw->num_targets, 2);
84 
85         /* Reserved */
86         build_append_int_noprefix(table_data, 0, 4);
87 
88         /* Base HPA */
89         build_append_int_noprefix(table_data, fw->mr.addr, 8);
90 
91         /* Window Size */
92         build_append_int_noprefix(table_data, fw->size, 8);
93 
94         /* Host Bridge Interleave Ways */
95         build_append_int_noprefix(table_data, fw->enc_int_ways, 1);
96 
97         /* Host Bridge Interleave Arithmetic */
98         build_append_int_noprefix(table_data, 0, 1);
99 
100         /* Reserved */
101         build_append_int_noprefix(table_data, 0, 2);
102 
103         /* Host Bridge Interleave Granularity */
104         build_append_int_noprefix(table_data, fw->enc_int_gran, 4);
105 
106         /* Window Restrictions */
107         build_append_int_noprefix(table_data, 0x0f, 2); /* No restrictions */
108 
109         /* QTG ID */
110         build_append_int_noprefix(table_data, 0, 2);
111 
112         /* Host Bridge List (list of UIDs - currently bus_nr) */
113         for (i = 0; i < fw->num_targets; i++) {
114             g_assert(fw->target_hbs[i]);
115             build_append_int_noprefix(table_data, fw->target_hbs[i]->bus_nr, 4);
116         }
117     }
118 }
119 
120 static int cxl_foreach_pxb_hb(Object *obj, void *opaque)
121 {
122     Aml *cedt = opaque;
123 
124     if (object_dynamic_cast(obj, TYPE_PXB_CXL_DEVICE)) {
125         cedt_build_chbs(cedt->buf, PXB_CXL_DEV(obj));
126     }
127 
128     return 0;
129 }
130 
131 void cxl_build_cedt(GArray *table_offsets, GArray *table_data,
132                     BIOSLinker *linker, const char *oem_id,
133                     const char *oem_table_id, CXLState *cxl_state)
134 {
135     Aml *cedt;
136     AcpiTable table = { .sig = "CEDT", .rev = 1, .oem_id = oem_id,
137                         .oem_table_id = oem_table_id };
138 
139     acpi_add_table(table_offsets, table_data);
140     acpi_table_begin(&table, table_data);
141     cedt = init_aml_allocator();
142 
143     /* reserve space for CEDT header */
144 
145     object_child_foreach_recursive(object_get_root(), cxl_foreach_pxb_hb, cedt);
146     cedt_build_cfmws(cedt->buf, cxl_state);
147 
148     /* copy AML table into ACPI tables blob and patch header there */
149     g_array_append_vals(table_data, cedt->buf->data, cedt->buf->len);
150     free_aml_allocator();
151 
152     acpi_table_end(linker, &table);
153 }
154 
155 static Aml *__build_cxl_osc_method(void)
156 {
157     Aml *method, *if_uuid, *else_uuid, *if_arg1_not_1, *if_cxl, *if_caps_masked;
158     Aml *a_ctrl = aml_local(0);
159     Aml *a_cdw1 = aml_name("CDW1");
160 
161     method = aml_method("_OSC", 4, AML_NOTSERIALIZED);
162     /* CDW1 is used for the return value so is present whether or not a match occurs */
163     aml_append(method, aml_create_dword_field(aml_arg(3), aml_int(0), "CDW1"));
164 
165     /*
166      * Generate shared section between:
167      * CXL 2.0 - 9.14.2.1.4 and
168      * PCI Firmware Specification 3.0
169      * 4.5.1. _OSC Interface for PCI Host Bridge Devices
170      * The _OSC interface for a PCI/PCI-X/PCI Express hierarchy is
171      * identified by the Universal Unique IDentifier (UUID)
172      * 33DB4D5B-1FF7-401C-9657-7441C03DD766
173      * The _OSC interface for a CXL Host bridge is
174      * identified by the UUID 68F2D50B-C469-4D8A-BD3D-941A103FD3FC
175      * A CXL Host bridge is compatible with a PCI host bridge so
176      * for the shared section match both.
177      */
178     if_uuid = aml_if(
179         aml_lor(aml_equal(aml_arg(0),
180                           aml_touuid("33DB4D5B-1FF7-401C-9657-7441C03DD766")),
181                 aml_equal(aml_arg(0),
182                           aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC"))));
183     aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(4), "CDW2"));
184     aml_append(if_uuid, aml_create_dword_field(aml_arg(3), aml_int(8), "CDW3"));
185 
186     aml_append(if_uuid, aml_store(aml_name("CDW3"), a_ctrl));
187 
188     /*
189      *
190      * Allows OS control for all 5 features:
191      * PCIeHotplug SHPCHotplug PME AER PCIeCapability
192      */
193     aml_append(if_uuid, aml_and(a_ctrl, aml_int(0x1F), a_ctrl));
194 
195     /*
196      * Check _OSC revision.
197      * PCI Firmware specification 3.3 and CXL 2.0 both use revision 1
198      * Unknown Revision is CDW1 - BIT (3)
199      */
200     if_arg1_not_1 = aml_if(aml_lnot(aml_equal(aml_arg(1), aml_int(0x1))));
201     aml_append(if_arg1_not_1, aml_or(a_cdw1, aml_int(0x08), a_cdw1));
202     aml_append(if_uuid, if_arg1_not_1);
203 
204     if_caps_masked = aml_if(aml_lnot(aml_equal(aml_name("CDW3"), a_ctrl)));
205 
206     /* Capability bits were masked */
207     aml_append(if_caps_masked, aml_or(a_cdw1, aml_int(0x10), a_cdw1));
208     aml_append(if_uuid, if_caps_masked);
209 
210     aml_append(if_uuid, aml_store(aml_name("CDW2"), aml_name("SUPP")));
211     aml_append(if_uuid, aml_store(aml_name("CDW3"), aml_name("CTRL")));
212 
213     /* Update DWORD3 (the return value) */
214     aml_append(if_uuid, aml_store(a_ctrl, aml_name("CDW3")));
215 
216     /* CXL only section as per CXL 2.0 - 9.14.2.1.4 */
217     if_cxl = aml_if(aml_equal(
218         aml_arg(0), aml_touuid("68F2D50B-C469-4D8A-BD3D-941A103FD3FC")));
219     /* CXL support field */
220     aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(12), "CDW4"));
221     /* CXL capabilities */
222     aml_append(if_cxl, aml_create_dword_field(aml_arg(3), aml_int(16), "CDW5"));
223     aml_append(if_cxl, aml_store(aml_name("CDW4"), aml_name("SUPC")));
224     aml_append(if_cxl, aml_store(aml_name("CDW5"), aml_name("CTRC")));
225 
226     /* CXL 2.0 Port/Device Register access */
227     aml_append(if_cxl,
228                aml_or(aml_name("CDW5"), aml_int(0x1), aml_name("CDW5")));
229     aml_append(if_uuid, if_cxl);
230 
231     aml_append(if_uuid, aml_return(aml_arg(3)));
232     aml_append(method, if_uuid);
233 
234     /*
235      * If no UUID matched, return Unrecognized UUID via Arg3 DWord 1
236      * ACPI 6.4 - 6.2.11
237      * Unrecognised UUID - BIT(2)
238      */
239     else_uuid = aml_else();
240 
241     aml_append(else_uuid,
242                aml_or(aml_name("CDW1"), aml_int(0x4), aml_name("CDW1")));
243     aml_append(else_uuid, aml_return(aml_arg(3)));
244     aml_append(method, else_uuid);
245 
246     return method;
247 }
248 
249 void build_cxl_osc_method(Aml *dev)
250 {
251     aml_append(dev, aml_name_decl("SUPP", aml_int(0)));
252     aml_append(dev, aml_name_decl("CTRL", aml_int(0)));
253     aml_append(dev, aml_name_decl("SUPC", aml_int(0)));
254     aml_append(dev, aml_name_decl("CTRC", aml_int(0)));
255     aml_append(dev, __build_cxl_osc_method());
256 }
257