xref: /openbmc/qemu/hw/pci/slotid_cap.c (revision 786a4ea8)
1 #include "hw/pci/slotid_cap.h"
2 #include "hw/pci/pci.h"
3 #include "qemu/error-report.h"
4 
5 #define SLOTID_CAP_LENGTH 4
6 #define SLOTID_NSLOTS_SHIFT ctz32(PCI_SID_ESR_NSLOTS)
7 
8 int slotid_cap_init(PCIDevice *d, int nslots,
9                     uint8_t chassis,
10                     unsigned offset)
11 {
12     int cap;
13     if (!chassis) {
14         error_report("Bridge chassis not specified. Each bridge is required "
15                      "to be assigned a unique chassis id > 0.");
16         return -EINVAL;
17     }
18     if (nslots < 0 || nslots > (PCI_SID_ESR_NSLOTS >> SLOTID_NSLOTS_SHIFT)) {
19         /* TODO: error report? */
20         return -EINVAL;
21     }
22 
23     cap = pci_add_capability(d, PCI_CAP_ID_SLOTID, offset, SLOTID_CAP_LENGTH);
24     if (cap < 0) {
25         return cap;
26     }
27     /* We make each chassis unique, this way each bridge is First in Chassis */
28     d->config[cap + PCI_SID_ESR] = PCI_SID_ESR_FIC |
29         (nslots << SLOTID_NSLOTS_SHIFT);
30     d->cmask[cap + PCI_SID_ESR] = 0xff;
31     d->config[cap + PCI_SID_CHASSIS_NR] = chassis;
32     /* Note: Chassis number register is non-volatile,
33        so we don't reset it. */
34     /* TODO: store in eeprom? */
35     d->wmask[cap + PCI_SID_CHASSIS_NR] = 0xff;
36 
37     d->cap_present |= QEMU_PCI_CAP_SLOTID;
38     return 0;
39 }
40 
41 void slotid_cap_cleanup(PCIDevice *d)
42 {
43     /* TODO: cleanup config space? */
44     d->cap_present &= ~QEMU_PCI_CAP_SLOTID;
45 }
46