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-rw-r--r--src/device/hypertransport.c692
1 files changed, 692 insertions, 0 deletions
diff --git a/src/device/hypertransport.c b/src/device/hypertransport.c
new file mode 100644
index 0000000000..a6320fe666
--- /dev/null
+++ b/src/device/hypertransport.c
@@ -0,0 +1,692 @@
+/*
+ * This file is part of the coreboot project.
+ *
+ * Copyright (C) 2003-2004 Linux Networx
+ * (Written by Eric Biederman <ebiederman@lnxi.com> for Linux Networx)
+ * Copyright (C) 2004 David Hendricks <sc@flagen.com>
+ * Copyright (C) 2004 Li-Ta Lo <ollie@lanl.gov>
+ * Copyright (C) 2005-2006 Tyan
+ * (Written by Yinghai Lu <yhlu@tyan.com> for Tyan)
+ * Copyright (C) 2005-2006 Stefan Reinauer <stepan@openbios.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <lib.h>
+#include <console/console.h>
+#include <device/device.h>
+#include <device/path.h>
+#include <device/pci.h>
+#include <device/pci_ids.h>
+#include <device/hypertransport.h>
+
+/*
+ * The hypertransport link is already optimized in pre-RAM code so don't do
+ * it again.
+ */
+#define OPT_HT_LINK 0
+
+#if OPT_HT_LINK == 1
+#include <cpu/amd/model_fxx_rev.h>
+#endif
+
+static device_t ht_scan_get_devs(device_t *old_devices)
+{
+ device_t first, last;
+
+ first = *old_devices;
+ last = first;
+
+ /*
+ * Extract the chain of devices to (first through last) for the next
+ * hypertransport device.
+ */
+ while (last && last->sibling &&
+ (last->sibling->path.type == DEVICE_PATH_PCI) &&
+ (last->sibling->path.pci.devfn > last->path.pci.devfn))
+ {
+ last = last->sibling;
+ }
+
+ if (first) {
+ device_t child;
+
+ /* Unlink the chain from the list of old devices. */
+ *old_devices = last->sibling;
+ last->sibling = 0;
+
+ /* Now add the device to the list of devices on the bus. */
+ /* Find the last child of our parent. */
+ for (child = first->bus->children; child && child->sibling; )
+ child = child->sibling;
+
+ /* Place the chain on the list of children of their parent. */
+ if (child)
+ child->sibling = first;
+ else
+ first->bus->children = first;
+ }
+ return first;
+}
+
+#if OPT_HT_LINK == 1
+static unsigned ht_read_freq_cap(device_t dev, unsigned pos)
+{
+ /* Handle bugs in valid hypertransport frequency reporting. */
+ unsigned freq_cap;
+
+ freq_cap = pci_read_config16(dev, pos);
+ freq_cap &= ~(1 << HT_FREQ_VENDOR); /* Ignore Vendor HT frequencies. */
+
+ /* AMD 8131 Errata 48. */
+ if ((dev->vendor == PCI_VENDOR_ID_AMD) &&
+ (dev->device == PCI_DEVICE_ID_AMD_8131_PCIX)) {
+ freq_cap &= ~(1 << HT_FREQ_800Mhz);
+ }
+
+ /* AMD 8151 Errata 23. */
+ if ((dev->vendor == PCI_VENDOR_ID_AMD) &&
+ (dev->device == PCI_DEVICE_ID_AMD_8151_SYSCTRL)) {
+ freq_cap &= ~(1 << HT_FREQ_800Mhz);
+ }
+
+ /* AMD K8 unsupported 1GHz? */
+ if ((dev->vendor == PCI_VENDOR_ID_AMD) && (dev->device == 0x1100)) {
+#if CONFIG_K8_HT_FREQ_1G_SUPPORT
+
+#if !CONFIG_K8_REV_F_SUPPORT
+ /* Only e0 later suupport 1GHz HT. */
+ if (is_cpu_pre_e0())
+ freq_cap &= ~(1 << HT_FREQ_1000Mhz);
+#endif
+
+#else
+ freq_cap &= ~(1 << HT_FREQ_1000Mhz);
+#endif
+ }
+
+ return freq_cap;
+}
+#endif
+
+struct ht_link {
+ struct device *dev;
+ unsigned pos;
+ unsigned char ctrl_off, config_off, freq_off, freq_cap_off;
+};
+
+static int ht_setup_link(struct ht_link *prev, device_t dev, unsigned pos)
+{
+#if OPT_HT_LINK == 1
+ static const u8 link_width_to_pow2[] = { 3, 4, 0, 5, 1, 2, 0, 0 };
+ static const u8 pow2_to_link_width[] = { 7, 4, 5, 0, 1, 3 };
+ unsigned present_width_cap, upstream_width_cap;
+ unsigned present_freq_cap, upstream_freq_cap;
+ unsigned ln_present_width_in, ln_upstream_width_in;
+ unsigned ln_present_width_out, ln_upstream_width_out;
+ unsigned freq, old_freq;
+ unsigned present_width, upstream_width, old_width;
+#endif
+ struct ht_link cur[1];
+ int reset_needed;
+ int linkb_to_host;
+
+ /* Set the hypertransport link width and frequency. */
+ reset_needed = 0;
+ /*
+ * See which side of the device our previous write to set the unitid
+ * came from.
+ */
+ cur->dev = dev;
+ cur->pos = pos;
+ linkb_to_host =
+ (pci_read_config16(cur->dev, cur->pos + PCI_CAP_FLAGS) >> 10) & 1;
+
+ if (!linkb_to_host) {
+ cur->ctrl_off = PCI_HT_CAP_SLAVE_CTRL0;
+ cur->config_off = PCI_HT_CAP_SLAVE_WIDTH0;
+ cur->freq_off = PCI_HT_CAP_SLAVE_FREQ0;
+ cur->freq_cap_off = PCI_HT_CAP_SLAVE_FREQ_CAP0;
+ } else {
+ cur->ctrl_off = PCI_HT_CAP_SLAVE_CTRL1;
+ cur->config_off = PCI_HT_CAP_SLAVE_WIDTH1;
+ cur->freq_off = PCI_HT_CAP_SLAVE_FREQ1;
+ cur->freq_cap_off = PCI_HT_CAP_SLAVE_FREQ_CAP1;
+ }
+
+#if OPT_HT_LINK == 1
+ /* Read the capabilities. */
+ present_freq_cap =
+ ht_read_freq_cap(cur->dev, cur->pos + cur->freq_cap_off);
+ upstream_freq_cap =
+ ht_read_freq_cap(prev->dev, prev->pos + prev->freq_cap_off);
+ present_width_cap =
+ pci_read_config8(cur->dev, cur->pos + cur->config_off);
+ upstream_width_cap =
+ pci_read_config8(prev->dev, prev->pos + prev->config_off);
+
+ /* Calculate the highest useable frequency. */
+ freq = log2(present_freq_cap & upstream_freq_cap);
+
+ /* Calculate the highest width. */
+ ln_upstream_width_in = link_width_to_pow2[upstream_width_cap & 7];
+ ln_present_width_out = link_width_to_pow2[(present_width_cap >> 4) & 7];
+ if (ln_upstream_width_in > ln_present_width_out)
+ ln_upstream_width_in = ln_present_width_out;
+ upstream_width = pow2_to_link_width[ln_upstream_width_in];
+ present_width = pow2_to_link_width[ln_upstream_width_in] << 4;
+
+ ln_upstream_width_out =
+ link_width_to_pow2[(upstream_width_cap >> 4) & 7];
+ ln_present_width_in = link_width_to_pow2[present_width_cap & 7];
+ if (ln_upstream_width_out > ln_present_width_in)
+ ln_upstream_width_out = ln_present_width_in;
+ upstream_width |= pow2_to_link_width[ln_upstream_width_out] << 4;
+ present_width |= pow2_to_link_width[ln_upstream_width_out];
+
+ /* Set the current device. */
+ old_freq = pci_read_config8(cur->dev, cur->pos + cur->freq_off);
+ old_freq &= 0x0f;
+ if (freq != old_freq) {
+ unsigned new_freq;
+ pci_write_config8(cur->dev, cur->pos + cur->freq_off, freq);
+ reset_needed = 1;
+ printk(BIOS_SPEW, "HyperT FreqP old %x new %x\n",old_freq,freq);
+ new_freq = pci_read_config8(cur->dev, cur->pos + cur->freq_off);
+ new_freq &= 0x0f;
+ if (new_freq != freq) {
+ printk(BIOS_ERR, "%s Hypertransport frequency would "
+ "not set. Wanted: %x, got: %x\n",
+ dev_path(dev), freq, new_freq);
+ }
+ }
+ old_width = pci_read_config8(cur->dev, cur->pos + cur->config_off + 1);
+ if (present_width != old_width) {
+ unsigned new_width;
+ pci_write_config8(cur->dev, cur->pos + cur->config_off + 1,
+ present_width);
+ reset_needed = 1;
+ printk(BIOS_SPEW, "HyperT widthP old %x new %x\n",
+ old_width, present_width);
+ new_width = pci_read_config8(cur->dev,
+ cur->pos + cur->config_off + 1);
+ if (new_width != present_width) {
+ printk(BIOS_ERR, "%s Hypertransport width would not "
+ "set. Wanted: %x, got: %x\n",
+ dev_path(dev), present_width, new_width);
+ }
+ }
+
+ /* Set the upstream device. */
+ old_freq = pci_read_config8(prev->dev, prev->pos + prev->freq_off);
+ old_freq &= 0x0f;
+ if (freq != old_freq) {
+ unsigned new_freq;
+ pci_write_config8(prev->dev, prev->pos + prev->freq_off, freq);
+ reset_needed = 1;
+ printk(BIOS_SPEW, "HyperT freqU old %x new %x\n",
+ old_freq, freq);
+ new_freq =
+ pci_read_config8(prev->dev, prev->pos + prev->freq_off);
+ new_freq &= 0x0f;
+ if (new_freq != freq) {
+ printk(BIOS_ERR, "%s Hypertransport frequency would "
+ "not set. Wanted: %x, got: %x\n",
+ dev_path(prev->dev), freq, new_freq);
+ }
+ }
+ old_width =
+ pci_read_config8(prev->dev, prev->pos + prev->config_off + 1);
+ if (upstream_width != old_width) {
+ unsigned new_width;
+ pci_write_config8(prev->dev, prev->pos + prev->config_off + 1,
+ upstream_width);
+ reset_needed = 1;
+ printk(BIOS_SPEW, "HyperT widthU old %x new %x\n", old_width,
+ upstream_width);
+ new_width = pci_read_config8(prev->dev,
+ prev->pos + prev->config_off + 1);
+ if (new_width != upstream_width) {
+ printk(BIOS_ERR, "%s Hypertransport width would not "
+ "set. Wanted: %x, got: %x\n",
+ dev_path(prev->dev), upstream_width, new_width);
+ }
+ }
+#endif
+
+ /*
+ * Remember the current link as the previous link, but look at the
+ * other offsets.
+ */
+ prev->dev = cur->dev;
+ prev->pos = cur->pos;
+ if (cur->ctrl_off == PCI_HT_CAP_SLAVE_CTRL0) {
+ prev->ctrl_off = PCI_HT_CAP_SLAVE_CTRL1;
+ prev->config_off = PCI_HT_CAP_SLAVE_WIDTH1;
+ prev->freq_off = PCI_HT_CAP_SLAVE_FREQ1;
+ prev->freq_cap_off = PCI_HT_CAP_SLAVE_FREQ_CAP1;
+ } else {
+ prev->ctrl_off = PCI_HT_CAP_SLAVE_CTRL0;
+ prev->config_off = PCI_HT_CAP_SLAVE_WIDTH0;
+ prev->freq_off = PCI_HT_CAP_SLAVE_FREQ0;
+ prev->freq_cap_off = PCI_HT_CAP_SLAVE_FREQ_CAP0;
+ }
+
+ return reset_needed;
+}
+
+static unsigned ht_lookup_slave_capability(struct device *dev)
+{
+ unsigned pos;
+
+ pos = 0;
+ do {
+ pos = pci_find_next_capability(dev, PCI_CAP_ID_HT, pos);
+ if (pos) {
+ u16 flags;
+ flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
+ printk(BIOS_SPEW, "flags: 0x%04x\n", flags);
+ if ((flags >> 13) == 0) {
+ /* Entry is a slave secondary, success... */
+ break;
+ }
+ }
+ } while (pos);
+
+ return pos;
+}
+
+static void ht_collapse_early_enumeration(struct bus *bus,
+ unsigned offset_unitid)
+{
+ unsigned int devfn;
+ struct ht_link prev;
+ u16 ctrl;
+
+ /* Initialize the hypertransport enumeration state. */
+ prev.dev = bus->dev;
+ prev.pos = bus->cap;
+ prev.ctrl_off = PCI_HT_CAP_HOST_CTRL;
+ prev.config_off = PCI_HT_CAP_HOST_WIDTH;
+ prev.freq_off = PCI_HT_CAP_HOST_FREQ;
+ prev.freq_cap_off = PCI_HT_CAP_HOST_FREQ_CAP;
+
+ /* Wait until the link initialization is complete. */
+ do {
+ ctrl = pci_read_config16(prev.dev, prev.pos + prev.ctrl_off);
+
+ /* Is this the end of the hypertransport chain? */
+ if (ctrl & (1 << 6))
+ return;
+
+ /* Has the link failed? */
+ if (ctrl & (1 << 4)) {
+ /*
+ * Either the link has failed, or we have a CRC error.
+ * Sometimes this can happen due to link retrain, so
+ * lets knock it down and see if its transient.
+ */
+ ctrl |= ((1 << 4) | (1 << 8)); /* Link fail + CRC */
+ pci_write_config16(prev.dev, prev.pos + prev.ctrl_off,
+ ctrl);
+ ctrl = pci_read_config16(prev.dev,
+ prev.pos + prev.ctrl_off);
+ if (ctrl & ((1 << 4) | (1 << 8))) {
+ printk(BIOS_ALERT, "Detected error on "
+ "Hypertransport link\n");
+ return;
+ }
+ }
+ } while ((ctrl & (1 << 5)) == 0);
+
+ /* Actually, only for one HT device HT chain, and unitid is 0. */
+#if !CONFIG_HT_CHAIN_UNITID_BASE
+ if (offset_unitid)
+ return;
+#endif
+
+ /* Check if is already collapsed. */
+ if ((!offset_unitid) || (offset_unitid
+ && (!((CONFIG_HT_CHAIN_END_UNITID_BASE == 0)
+ && (CONFIG_HT_CHAIN_END_UNITID_BASE
+ < CONFIG_HT_CHAIN_UNITID_BASE))))) {
+
+ struct device dummy;
+ u32 id;
+
+ dummy.bus = bus;
+ dummy.path.type = DEVICE_PATH_PCI;
+ dummy.path.pci.devfn = PCI_DEVFN(0, 0);
+
+ id = pci_read_config32(&dummy, PCI_VENDOR_ID);
+ if (!((id == 0xffffffff) || (id == 0x00000000)
+ || (id == 0x0000ffff) || (id == 0xffff0000))) {
+ return;
+ }
+ }
+
+ /* Spin through the devices and collapse any early HT enumeration. */
+ for (devfn = PCI_DEVFN(1, 0); devfn <= 0xff; devfn += 8) {
+ struct device dummy;
+ u32 id;
+ unsigned pos, flags;
+
+ dummy.bus = bus;
+ dummy.path.type = DEVICE_PATH_PCI;
+ dummy.path.pci.devfn = devfn;
+
+ id = pci_read_config32(&dummy, PCI_VENDOR_ID);
+ if ((id == 0xffffffff) || (id == 0x00000000)
+ || (id == 0x0000ffff) || (id == 0xffff0000)) {
+ continue;
+ }
+
+ dummy.vendor = id & 0xffff;
+ dummy.device = (id >> 16) & 0xffff;
+ dummy.hdr_type = pci_read_config8(&dummy, PCI_HEADER_TYPE);
+
+ pos = ht_lookup_slave_capability(&dummy);
+ if (!pos)
+ continue;
+
+ /* Clear the unitid. */
+ flags = pci_read_config16(&dummy, pos + PCI_CAP_FLAGS);
+ flags &= ~0x1f;
+ pci_write_config16(&dummy, pos + PCI_CAP_FLAGS, flags);
+ printk(BIOS_SPEW, "Collapsing %s [%04x/%04x]\n",
+ dev_path(&dummy), dummy.vendor, dummy.device);
+ }
+}
+
+unsigned int hypertransport_scan_chain(struct bus *bus, unsigned min_devfn,
+ unsigned max_devfn, unsigned int max,
+ unsigned *ht_unitid_base,
+ unsigned offset_unitid)
+{
+ /*
+ * Even CONFIG_HT_CHAIN_UNITID_BASE == 0, we still can go through this
+ * function, because of end_of_chain check. Also, we need it to
+ * optimize link.
+ */
+ unsigned int next_unitid, last_unitid, min_unitid, max_unitid;
+ device_t old_devices, dev, func, last_func = 0;
+ struct ht_link prev;
+ int ht_dev_num = 0;
+
+ min_unitid = (offset_unitid) ? CONFIG_HT_CHAIN_UNITID_BASE : 1;
+
+#if CONFIG_HT_CHAIN_END_UNITID_BASE != 0x20
+ /*
+ * Let's record the device of last HT device, so we can set the unitid
+ * to CONFIG_HT_CHAIN_END_UNITID_BASE.
+ */
+ unsigned int real_last_unitid = 0, end_used = 0;
+ u8 real_last_pos = 0;
+ device_t real_last_dev = NULL;
+#endif
+
+ /* Restore the hypertransport chain to it's unitialized state. */
+ ht_collapse_early_enumeration(bus, offset_unitid);
+
+ /* See which static device nodes I have. */
+ old_devices = bus->children;
+ bus->children = 0;
+
+ /* Initialize the hypertransport enumeration state. */
+ prev.dev = bus->dev;
+ prev.pos = bus->cap;
+
+ prev.ctrl_off = PCI_HT_CAP_HOST_CTRL;
+ prev.config_off = PCI_HT_CAP_HOST_WIDTH;
+ prev.freq_off = PCI_HT_CAP_HOST_FREQ;
+ prev.freq_cap_off = PCI_HT_CAP_HOST_FREQ_CAP;
+
+ /* If present, assign unitid to a hypertransport chain. */
+ last_unitid = min_unitid -1;
+ max_unitid = next_unitid = min_unitid;
+ do {
+ u8 pos;
+ u16 flags, ctrl;
+ unsigned int count, static_count;
+
+ last_unitid = next_unitid;
+
+ /* Wait until the link initialization is complete. */
+ do {
+ ctrl = pci_read_config16(prev.dev,
+ prev.pos + prev.ctrl_off);
+
+ /* End of chain? */
+ if (ctrl & (1 << 6))
+ goto end_of_chain;
+
+ if (ctrl & ((1 << 4) | (1 << 8))) {
+ /*
+ * Either the link has failed, or we have a CRC
+ * error. Sometimes this can happen due to link
+ * retrain, so lets knock it down and see if
+ * it's transient.
+ */
+ ctrl |= ((1 << 4) | (1 <<8)); // Link fail + CRC
+ pci_write_config16(prev.dev,
+ prev.pos + prev.ctrl_off, ctrl);
+ ctrl = pci_read_config16(prev.dev,
+ prev.pos + prev.ctrl_off);
+ if (ctrl & ((1 << 4) | (1 << 8))) {
+ printk(BIOS_ALERT, "Detected error on "
+ "hypertransport link\n");
+ goto end_of_chain;
+ }
+ }
+ } while ((ctrl & (1 << 5)) == 0);
+
+
+ /* Get and setup the device_structure. */
+ dev = ht_scan_get_devs(&old_devices);
+
+ /* See if a device is present and setup the device structure. */
+ dev = pci_probe_dev(dev, bus, 0);
+ if (!dev || !dev->enabled)
+ break;
+
+ /* Find the hypertransport link capability. */
+ pos = ht_lookup_slave_capability(dev);
+ if (pos == 0) {
+ printk(BIOS_ERR, "%s Hypertransport link capability "
+ "not found", dev_path(dev));
+ break;
+ }
+
+ /* Update the unitid of the current device. */
+ flags = pci_read_config16(dev, pos + PCI_CAP_FLAGS);
+
+ /*
+ * If the devices has a unitid set and is at devfn 0 we are
+ * done. This can happen with shadow hypertransport devices,
+ * or if we have reached the bottom of a HT device chain.
+ */
+ if (flags & 0x1f)
+ break;
+
+ flags &= ~0x1f; /* Mask out base Unit ID. */
+
+ count = (flags >> 5) & 0x1f; /* Het unit count. */
+
+#if CONFIG_HT_CHAIN_END_UNITID_BASE != 0x20
+ if (offset_unitid) {
+ /* max_devfn will be (0x17<<3)|7 or (0x1f<<3)|7. */
+ if (next_unitid > (max_devfn >> 3)) {
+ if (!end_used) {
+ next_unitid =
+ CONFIG_HT_CHAIN_END_UNITID_BASE;
+ end_used = 1;
+ } else {
+ goto end_of_chain;
+ }
+ }
+ }
+#endif
+
+ flags |= next_unitid & 0x1f;
+ pci_write_config16(dev, pos + PCI_CAP_FLAGS, flags);
+
+ /* Update the unitid in the device structure. */
+ static_count = 1;
+ for (func = dev; func; func = func->sibling) {
+ func->path.pci.devfn += (next_unitid << 3);
+ static_count = (func->path.pci.devfn >> 3)
+ - (dev->path.pci.devfn >> 3) + 1;
+ last_func = func;
+ }
+
+ /* Compute the number of unitids consumed. */
+ printk(BIOS_SPEW, "%s count: %04x static_count: %04x\n",
+ dev_path(dev), count, static_count);
+ if (count < static_count)
+ count = static_count;
+
+ /* Update the unitid of the next device. */
+ ht_unitid_base[ht_dev_num] = next_unitid;
+ ht_dev_num++;
+
+#if CONFIG_HT_CHAIN_END_UNITID_BASE != 0x20
+ if (offset_unitid) {
+ real_last_pos = pos;
+ real_last_unitid = next_unitid;
+ real_last_dev = dev;
+ }
+#endif
+ next_unitid += count;
+ if (next_unitid > max_unitid)
+ max_unitid = next_unitid;
+
+ /* Setup the hypetransport link. */
+ bus->reset_needed |= ht_setup_link(&prev, dev, pos);
+
+ printk(BIOS_DEBUG, "%s [%04x/%04x] %s next_unitid: %04x\n",
+ dev_path(dev), dev->vendor, dev->device,
+ (dev->enabled? "enabled" : "disabled"), next_unitid);
+
+ } while (last_unitid != next_unitid);
+
+end_of_chain:
+
+#if OPT_HT_LINK == 1
+ if (bus->reset_needed)
+ printk(BIOS_INFO, "HyperT reset needed\n");
+ else
+ printk(BIOS_DEBUG, "HyperT reset not needed\n");
+#endif
+
+#if CONFIG_HT_CHAIN_END_UNITID_BASE != 0x20
+ if (offset_unitid && (ht_dev_num > 1)
+ && (real_last_unitid != CONFIG_HT_CHAIN_END_UNITID_BASE)
+ && !end_used) {
+ u16 flags;
+ flags = pci_read_config16(real_last_dev,
+ real_last_pos + PCI_CAP_FLAGS);
+ flags &= ~0x1f;
+ flags |= CONFIG_HT_CHAIN_END_UNITID_BASE & 0x1f;
+ pci_write_config16(real_last_dev,
+ real_last_pos + PCI_CAP_FLAGS, flags);
+
+ for (func = real_last_dev; func; func = func->sibling) {
+ func->path.pci.devfn -= ((real_last_unitid
+ - CONFIG_HT_CHAIN_END_UNITID_BASE) << 3);
+ last_func = func;
+ }
+
+ /* Update last one. */
+ ht_unitid_base[ht_dev_num-1] = CONFIG_HT_CHAIN_END_UNITID_BASE;
+
+ printk(BIOS_DEBUG, " unitid: %04x --> %04x\n",
+ real_last_unitid, CONFIG_HT_CHAIN_END_UNITID_BASE);
+ }
+#endif
+ next_unitid = max_unitid;
+
+ if (next_unitid > 0x20)
+ next_unitid = 0x20;
+
+ if ((bus->secondary == 0) && (next_unitid > 0x18))
+ next_unitid = 0x18; /* Avoid K8 on bus 0. */
+
+ /*
+ * Die if any leftover static devices are are found. There's probably
+ * a problem in devicetree.cb.
+ */
+ if (old_devices) {
+ device_t left;
+ for (left = old_devices; left; left = left->sibling)
+ printk(BIOS_DEBUG, "%s\n", dev_path(left));
+
+ printk(BIOS_ERR, "HT: Leftover static devices. "
+ "Check your devicetree.cb\n");
+
+ /*
+ * Put back the leftover static device, and let pci_scan_bus()
+ * disable it.
+ */
+ if (last_func && !last_func->sibling)
+ last_func->sibling = old_devices;
+ }
+
+ /* Now that nothing is overlapping it is safe to scan the children. */
+ max = pci_scan_bus(bus, 0x00, ((next_unitid - 1) << 3) | 7, max);
+ return max;
+}
+
+/**
+ * Scan a PCI bridge and the buses behind the bridge.
+ *
+ * Determine the existence of buses behind the bridge. Set up the bridge
+ * according to the result of the scan.
+ *
+ * This function is the default scan_bus() method for PCI bridge devices.
+ *
+ * @param bus TODO
+ * @param min_devfn TODO
+ * @param max_devfn TODO
+ * @param max The highest bus number assgined up to now.
+ * @return The maximum bus number found, after scanning all subordinate busses.
+ */
+static unsigned int hypertransport_scan_chain_x(struct bus *bus,
+ unsigned int min_devfn, unsigned int max_devfn, unsigned int max)
+{
+ unsigned int ht_unitid_base[4];
+ unsigned int offset_unitid = 1;
+ return hypertransport_scan_chain(bus, min_devfn, max_devfn, max,
+ ht_unitid_base, offset_unitid);
+}
+
+unsigned int ht_scan_bridge(struct device *dev, unsigned int max)
+{
+ return do_pci_scan_bridge(dev, max, hypertransport_scan_chain_x);
+}
+
+/** Default device operations for hypertransport bridges */
+static struct pci_operations ht_bus_ops_pci = {
+ .set_subsystem = 0,
+};
+
+struct device_operations default_ht_ops_bus = {
+ .read_resources = pci_bus_read_resources,
+ .set_resources = pci_dev_set_resources,
+ .enable_resources = pci_bus_enable_resources,
+ .init = 0,
+ .scan_bus = ht_scan_bridge,
+ .enable = 0,
+ .reset_bus = pci_bus_reset,
+ .ops_pci = &ht_bus_ops_pci,
+};