- First pass at code for generic link width and size determination
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@999 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/devices/pci_device.c b/src/devices/pci_device.c
index 1c6498c..a951aa5 100644
--- a/src/devices/pci_device.c
+++ b/src/devices/pci_device.c
@@ -473,7 +473,8 @@
struct device *old_devices;
struct device *child;
#if HYPERTRANSPORT_SUPPORT
- unsigned next_unitid, last_unitid;
+ unsigned next_unitid, last_unitid, previous_unitid;
+ int reset_needed;
#endif
printk_debug("PCI: pci_scan_bus for bus %d\n", bus->secondary);
@@ -486,20 +487,19 @@
#if HYPERTRANSPORT_SUPPORT
- /* If present assign unitid to a hypertransport chain */
- next_unitid = 1;
- do {
+ /* Spin through the devices and collapse any early
+ * hypertransport enumeration.
+ */
+ for(devfn = 0; devfn <= 0xff; devfn += 8) {
struct device dummy;
uint32_t id;
uint8_t hdr_type, pos;
- last_unitid = next_unitid;
-
- dummy.bus = bus;
- dummy.devfn = 0;
+ dummy.bus = bus;
+ dummy.devfn = devfn;
id = pci_read_config32(&dummy, PCI_VENDOR_ID);
- if (id == 0xffffffff || id == 0x00000000 ||
+ if (id == 0xffffffff || id == 0x00000000 ||
id == 0x0000ffff || id == 0xffff0000) {
- break;
+ continue;
}
hdr_type = pci_read_config8(&dummy, PCI_HEADER_TYPE);
pos = 0;
@@ -521,19 +521,151 @@
flags = pci_read_config16(&dummy, pos + PCI_CAP_FLAGS);
printk_debug("flags: 0x%04x\n", (unsigned)flags);
if ((flags >> 13) == 0) {
- unsigned count;
+ /* Clear the unitid */
flags &= ~0x1f;
- flags |= next_unitid & 0x1f;
- count = (flags >> 5) & 0x1f;
- printk_debug("unitid: 0x%02x, count: 0x%02x\n",
- next_unitid, count);
pci_write_config16(&dummy, pos + PCI_CAP_FLAGS, flags);
- next_unitid += count;
break;
}
}
pos = pci_read_config8(&dummy, pos + PCI_CAP_LIST_NEXT);
}
+ }
+ /* If present assign unitid to a hypertransport chain */
+ last_unitid = 0;
+ next_unitid = 1;
+ do {
+ struct device dummy;
+ uint32_t id;
+ uint8_t hdr_type, pos, previous_pos;
+
+ previous_unitid = last_unitid;
+ last_unitid = next_unitid;
+
+ /* Read the next unassigned device off the stack */
+ dummy.bus = bus;
+ dummy.devfn = 0;
+ id = pci_read_config32(&dummy, PCI_VENDOR_ID);
+ /* If the chain is enumerated quit */
+ if (id == 0xffffffff || id == 0x00000000 ||
+ id == 0x0000ffff || id == 0xffff0000) {
+ break;
+ }
+ hdr_type = pci_read_config8(&dummy, PCI_HEADER_TYPE);
+ pos = 0;
+ switch(hdr_type & 0x7f) {
+ case PCI_HEADER_TYPE_NORMAL:
+ case PCI_HEADER_TYPE_BRIDGE:
+ pos = PCI_CAPABILITY_LIST;
+ break;
+ }
+ if (pos > PCI_CAP_LIST_NEXT) {
+ pos = pci_read_config8(&dummy, pos);
+ }
+ while(pos != 0) { /* loop through the linked list */
+ uint8_t cap;
+ cap = pci_read_config8(&dummy, pos + PCI_CAP_LIST_ID);
+ printk_debug("Capability: 0x%02x @ 0x%02x\n", cap, pos);
+ if (cap == PCI_CAP_ID_HT) {
+ uint16_t flags;
+ uint16_t links;
+ flags = pci_read_config16(&dummy, pos + PCI_CAP_FLAGS);
+ printk_debug("flags: 0x%04x\n", (unsigned)flags);
+ if ((flags >> 13) == 0) { /* Entry is a Slave secondary */
+ struct device last, previous;
+ unsigned count;
+ unsigned width;
+ flags &= ~0x1f; /* mask out base unit ID */
+ flags |= next_unitid & 0x1f; /* assign ID */
+ count = (flags >> 5) & 0x1f; /* get unit count */
+ printk_debug("unitid: 0x%02x, count: 0x%02x\n",
+ next_unitid, count);
+ pci_write_config16(&dummy, pos + PCI_CAP_FLAGS, flags);
+ next_unitid += count;
+
+ if (previous_unitid == 0) { /* the link is back to the host */
+ /* calculate the previous pos for the host */
+ previous_pos = 0x80;
+ previous.bus = 0;
+ previous.devfn = 0x18 << 3;
+#warning "FIXME we should not hard code this!"
+ } else {
+ previous.bus = bus;
+ previous.devfn = previous_unitid << 3;
+ }
+ last.bus = bus;
+ last.devfn = last_unitid << 3;
+ /* Set link width and frequency */
+ flags = pci_read_config16(&last, pos + PCI_HT_CAP_SLAVE_FREQ_CAP0);
+ cap = pci_read_config8(&last, pos + PCI_HT_CAP_SLAVE_WIDTH0);
+ if(previous_unitid == 0) { /* the link is back to the host */
+ links = pci_read_config16(&previous,
+ previous_pos + PCI_HT_CAP_HOST_FREQ_CAP);
+ width = pci_read_config8(&previous,
+ previous_pos + PCI_HT_CAP_HOST_WIDTH);
+ }
+ else { /* The link is back up the chain */
+ links = pci_read_config16(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_FREQ_CAP1);
+ width = pci_read_config8(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_WIDTH1);
+ }
+ /* Calculate the highest possible frequency */
+ links &= flags;
+ for(flags = 0x40, count = 6; count; count--, flags >>= 1) {
+ if(flags & links) break;
+ }
+ /* Calculate the highest width */
+ width &= cap;
+ /* set the present device */
+ if(count != pci_read_config8(&last, pos + PCI_HT_CAP_HOST_FREQ)) {
+ pci_write_config8(&last, pos + PCI_HT_CAP_HOST_FREQ, count);
+ reset_needed = 1;
+ }
+ if(width != pci_read_config8(&last, pos + PCI_HT_CAP_SLAVE_WIDTH0 + 1)) {
+ pci_write_config8(&last,
+ pos + PCI_HT_CAP_SLAVE_WIDTH0 + 1, width);
+ reset_needed = 1;
+ }
+
+ /* set the upstream device */
+ if(previous_unitid == 0) { /* the link is back to the host */
+ cap = pci_read_config8(&previous, previous_pos + PCI_HT_CAP_HOST_FREQ);
+ cap &= 0x0f;
+ if(count != cap) {
+ pci_write_config8(&previous,
+ previous_pos + PCI_HT_CAP_HOST_FREQ, count);
+ reset_needed = 1;
+ }
+ cap = pci_read_config8(&previous, previous_pos + PCI_HT_CAP_HOST_WIDTH + 1);
+ if(width != cap) {
+ pci_write_config8(&previous,
+ previous_pos + PCI_HT_CAP_HOST_WIDTH + 1, width);
+ reset_needed = 1;
+ }
+ }
+ else { /* The link is back up the chain */
+ cap = pci_read_config8(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_FREQ1);
+ cap &= 0x0f;
+ if(count != cap) {
+ pci_write_config8(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_FREQ1, count);
+ reset_needed = 1;
+ }
+ cap = pci_read_config8(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_WIDTH1 + 1);
+ if(width != cap) {
+ pci_write_config8(&previous,
+ previous_pos + PCI_HT_CAP_SLAVE_WIDTH1, width);
+ reset_needed = 1;
+ }
+ }
+ break;
+ }
+ }
+ pos = pci_read_config8(&dummy, pos + PCI_CAP_LIST_NEXT);
+ }
+ previous_pos = pos;
} while((last_unitid != next_unitid) && (next_unitid <= 0x1f));
#endif /* HYPERTRANSPORT_SUPPORT */