Author: myles
Date: 2008-11-04 22:32:59 +0100 (Tue, 04 Nov 2008)
New Revision: 980
Modified:
coreboot-v3/device/pci_device.c
Log:
This patch clarifies/adds comments and changes names in device/pci_device.c
It also changes %p debug statements in various places. I think they get in
the way of diffs when you have log files to compare. I don't want to see the
allocation differences most of the time. I turned most of them into NULL
checks. If they were supposed to be "Where are we in device allocation?"
checks, we could make them into that too.
It's a work-in-progress. Comments welcome.
I think most of the changes are self explanatory, but this one might not be:
If you are reading all the BARs from a device, and you come to a 64-bit BAR.
No matter why you skip it, you should skip it as a 64-bit BAR, and not try to
read the upper half as the next 32-bit BAR.
Because of that, set the 64-bit flag IORESOURCE_PCI64 early, and don't clear
it on return.
Signed-off-by: Myles Watson <mylesgw(a)gmail.com>
Acked-by: Ronald G. Minnich <rminnich(a)gmail.com>
Modified: coreboot-v3/device/pci_device.c
===================================================================
--- coreboot-v3/device/pci_device.c 2008-11-04 17:00:07 UTC (rev 979)
+++ coreboot-v3/device/pci_device.c 2008-11-04 21:32:59 UTC (rev 980)
@@ -30,11 +30,13 @@
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_ids.h>
+/* We should move these so they're really config options */
#define CONFIG_HYPERTRANSPORT_PLUGIN_SUPPORT 0
#define CONFIG_PCIX_PLUGIN_SUPPORT 0
#define CONFIG_PCIE_PLUGIN_SUPPORT 0
#define CONFIG_CARDBUS_PLUGIN_SUPPORT 0
#define CONFIG_AGP_PLUGIN_SUPPORT 0
+
#if CONFIG_HYPERTRANSPORT_PLUGIN_SUPPORT == 1
#include <device/hypertransport.h>
#endif
@@ -100,8 +102,16 @@
return ones ^ zeroes;
}
-unsigned int pci_find_next_capability(struct device *dev, unsigned int cap,
- unsigned int last)
+/**
+ * Given a device, a capability type, and a last position, return the next
+ * matching capability. Always start at the head of the list.
+ *
+ * @param dev Pointer to the device structure.
+ * @param cap_type PCI_CAP_LIST_ID of the PCI capability we're looking for.
+ * @param last_pos Location of the PCI capability register to start from.
+ */
+unsigned int pci_find_next_capability(struct device *dev, unsigned int cap_type,
+ unsigned int last_pos)
{
unsigned int pos;
unsigned int status;
@@ -124,27 +134,35 @@
}
pos = pci_read_config8(dev, pos);
while (reps-- && (pos >= 0x40)) { /* Loop through the linked list. */
- int this_cap;
+ int this_cap_type;
pos &= ~3;
- this_cap = pci_read_config8(dev, pos + PCI_CAP_LIST_ID);
- printk(BIOS_SPEW, "Capability: 0x%02x @ 0x%02x\n", cap, pos);
- if (this_cap == 0xff) {
+ this_cap_type = pci_read_config8(dev, pos + PCI_CAP_LIST_ID);
+ printk(BIOS_SPEW, "Capability: 0x%02x @ 0x%02x\n",
+ this_cap_type, pos);
+ if (this_cap_type == 0xff) {
break;
}
- if (!last && (this_cap == cap)) {
+ if (!last_pos && (this_cap_type == cap_type)) {
return pos;
}
- if (last == pos) {
- last = 0;
+ if (last_pos == pos) { /* Return the next match. */
+ last_pos = 0;
}
pos = pci_read_config8(dev, pos + PCI_CAP_LIST_NEXT);
}
return 0;
}
-unsigned int pci_find_capability(struct device *dev, unsigned int cap)
+/**
+ * Given a device, and a capability type, return the next matching
+ * capability. Always start at the head of the list.
+ *
+ * @param dev Pointer to the device structure.
+ * @param cap_type PCI_CAP_LIST_ID of the PCI capability we're looking for.
+ */
+unsigned int pci_find_capability(struct device *dev, unsigned int cap_type)
{
- return pci_find_next_capability(dev, cap, 0);
+ return pci_find_next_capability(dev, cap_type, 0);
}
/**
@@ -167,9 +185,9 @@
/* save the base address */
if (value & PCI_BASE_ADDRESS_SPACE_IO)
- base &= ~PCI_BASE_ADDRESS_IO_ATTR_MASK;
+ base = value & ~PCI_BASE_ADDRESS_IO_ATTR_MASK;
else
- base &= ~PCI_BASE_ADDRESS_MEM_ATTR_MASK;
+ base = value & ~PCI_BASE_ADDRESS_MEM_ATTR_MASK;
/* See which bits move. */
moving = pci_moving_config32(dev, index);
@@ -184,6 +202,7 @@
/* Find the high bits that move. */
moving |=
((resource_t) pci_moving_config32(dev, index + 4)) << 32;
+ resource->flags |= IORESOURCE_PCI64;
}
/* Find the resource constraints.
@@ -220,7 +239,11 @@
"%s register %02lx(%08lx), read-only ignoring it\n",
dev_path(dev), index, value);
}
- resource->flags = 0;
+ /* resource->flags = 0;
+ * Shouldn't zero because we'll get off with 64-bit BARs.
+ * Are there any others to save?
+ */
+ resource->flags &= ~IORESOURCE_PCI64;
} else if (attr & PCI_BASE_ADDRESS_SPACE_IO) {
/* An I/O mapped base address. */
attr &= PCI_BASE_ADDRESS_IO_ATTR_MASK;
@@ -244,7 +267,6 @@
} else if (attr == PCI_BASE_ADDRESS_MEM_LIMIT_64) {
/* 64bit limit. */
resource->limit = 0xffffffffffffffffULL;
- resource->flags |= IORESOURCE_PCI64;
} else {
/* Invalid value. */
resource->flags = 0;
@@ -258,6 +280,12 @@
return resource;
}
+/**
+ * Given a device and an index, read the size of the BAR for that register.
+ *
+ * @param dev Pointer to the device structure.
+ * @param index Address of the PCI configuration register.
+ */
static void pci_get_rom_resource(struct device *dev, unsigned long index)
{
struct resource *resource;
@@ -265,8 +293,7 @@
resource_t moving, limit;
if ((dev->on_mainboard) && (dev->rom_address == 0)) {
- // Skip it if rom_address is not set in MB Config.lb.
- // TODO: No more Config.lb in coreboot-v3.
+ // Skip it if rom_address is not set in the mainboard's dts.
return;
}
@@ -278,6 +305,7 @@
/* See which bits move. */
moving = pci_moving_config32(dev, index);
+
/* Clear the Enable bit. */
moving = moving & ~PCI_ROM_ADDRESS_ENABLE;
@@ -298,23 +326,19 @@
resource->gran += 1;
}
resource->limit = limit = moving | (resource->size - 1);
- }
-
- if (moving == 0) {
+ resource->flags |= IORESOURCE_MEM | IORESOURCE_READONLY;
+ } else {
if (value != 0) {
printk(BIOS_DEBUG,
"%s register %02lx(%08lx), read-only ignoring it\n",
dev_path(dev), index, value);
}
resource->flags = 0;
- } else {
- resource->flags |= IORESOURCE_MEM | IORESOURCE_READONLY;
}
/* For on board device with embedded ROM image, the ROM image is at
- * fixed address specified in the Config.lb, the dev->rom_address is
+ * fixed address specified in the dts, the dev->rom_address is
* inited by driver_pci_onboard_ops::enable_dev() */
- /* TODO: No more Config.lb in coreboot-v3. */
if ((dev->on_mainboard) && (dev->rom_address != 0)) {
resource->base = dev->rom_address;
resource->flags |= IORESOURCE_MEM | IORESOURCE_READONLY |
@@ -718,7 +742,7 @@
void pci_dev_init(struct device *dev)
{
- printk(BIOS_SPEW, "PCI: pci_dev_init\n");
+ printk(BIOS_SPEW, "PCI: pci_dev_init %s\n", dev->dtsname);
#ifdef CONFIG_PCI_OPTION_ROM_RUN
void run_bios(struct device *dev, unsigned long addr);
struct rom_header *rom, *ram;
@@ -774,7 +798,7 @@
* When only a PCI-Express capability is found the type
* is examined to see which type of bridge we have.
*
- * @param dev TODO
+ * @param dev Pointer to the device structure of the bridge.
* @return Appropriate bridge operations.
*/
static struct device_operations *get_pci_bridge_ops(struct device *dev)
@@ -831,9 +855,10 @@
}
/**
- * Set up PCI device operation.
+ * Set up PCI device operation. Check if it already has a driver. If not, use
+ * find_device_operations, or set to a default based on type.
*
- * @param dev TODO
+ * @param dev Pointer to the device whose pci_ops you want to set.
* @see pci_drivers
*/
static void set_pci_ops(struct device *dev)
@@ -842,8 +867,8 @@
struct device_id id;
if (dev->ops) {
- printk(BIOS_SPEW, "%s: dev %p(%s) already has ops %p\n",
- __func__, dev, dev->dtsname, dev->ops);
+ printk(BIOS_SPEW, "%s: dev %s already has ops of type %x\n",
+ __func__, dev->dtsname, dev->ops->id.type);
return;
}
@@ -888,8 +913,8 @@
dev->hdr_type);
}
}
- printk(BIOS_INFO, "%s: dev %p(%s) set ops to %p\n", __func__, dev,
- dev->dtsname, dev->ops);
+ printk(BIOS_INFO, "%s: dev %s set ops to type %x\n", __func__,
+ dev->dtsname, dev->ops->id.type);
return;
}
@@ -905,12 +930,12 @@
* @return Pointer to the device structure found or NULL of we have not
* allocated a device for this devfn yet.
*/
-static struct device *pci_scan_get_dev(struct device **list, unsigned int devfn)
+static struct device *pci_get_dev(struct device **list, unsigned int devfn)
{
struct device *dev;
dev = 0;
- printk(BIOS_SPEW, "%s: list is %p, *list is %p\n", __func__, list,
- *list);
+ printk(BIOS_SPEW, "%s: list is %sNULL, *list is %sNULL\n", __func__,
+ list?"NOT ":"", *list?"NOT ":"");
for (; *list; list = &(*list)->sibling) {
printk(BIOS_SPEW, "%s: check dev %s \n", __func__,
(*list)->dtsname);
@@ -927,7 +952,7 @@
/* Unlink from the list. */
dev = *list;
*list = (*list)->sibling;
- dev->sibling = 0;
+ dev->sibling = NULL;
break;
}
}
@@ -962,8 +987,8 @@
*
* @param dev Pointer to the device structure if it already is in the device
* tree, i.e. was specified in the dts. It may not exist on hardware,
- * however. Looking for hardware not yet in the device tree has this
- * parameter as NULL.
+ * however. When looking for hardware not yet in the device tree, this
+ * parameter is NULL.
* @param bus Pointer to the bus structure.
* @param devfn A device/function number.
* @return The device structure for the device if it exists in hardware
@@ -1021,7 +1046,6 @@
* this also handles optional devices that may not always
* show up.
*/
- /* If the chain is fully enumerated quit. */
if ((id == 0xffffffff) || (id == 0x00000000) ||
(id == 0x0000ffff) || (id == 0xffff0000)) {
if (dev->enabled) {
@@ -1034,6 +1058,7 @@
}
}
/* Read the rest of the PCI configuration information. */
+ /* Store the interesting information in the device structure. */
hdr_type = pci_read_config8(dev, PCI_HEADER_TYPE);
class = pci_read_config32(dev, PCI_CLASS_REVISION);
dev->status = pci_read_config16(dev, PCI_STATUS);
@@ -1043,15 +1068,22 @@
dev->irq_pin = pci_read_config8(dev, PCI_INTERRUPT_PIN);
dev->min_gnt = pci_read_config8(dev, PCI_MIN_GNT);
dev->max_lat = pci_read_config8(dev, PCI_MAX_LAT);
-#warning Per-device subsystem ID should only be read from the device if none has been specified for the device in the dts.
- dev->subsystem_vendor = pci_read_config16(dev, PCI_SUBSYSTEM_VENDOR_ID);
- dev->subsystem_device = pci_read_config16(dev, PCI_SUBSYSTEM_ID);
- /* Store the interesting information in the device structure. */
+ /*Per-device subsystem ID should only be read from the device if none
+ * has been specified for the device in the dts.
+ */
+ if (!dev->subsystem_vendor && !dev->subsystem_device) {
+ dev->subsystem_vendor =
+ pci_read_config16(dev, PCI_SUBSYSTEM_VENDOR_ID);
+ dev->subsystem_device =
+ pci_read_config16(dev, PCI_SUBSYSTEM_ID);
+ }
+
dev->id.type = DEVICE_ID_PCI;
dev->id.pci.vendor = id & 0xffff;
dev->id.pci.device = (id >> 16) & 0xffff;
dev->hdr_type = hdr_type;
+
/* Class code, the upper 3 bytes of PCI_CLASS_REVISION. */
dev->class = class >> 8;
@@ -1070,9 +1102,7 @@
dev->ops->phase3_enable(dev);
}
- /* Display the device and error if we don't have some PCI operations
- * for it.
- */
+ /* Display the device. */
printk(BIOS_DEBUG, "%s [%s] %s%s\n",
dev_path(dev), dev_id_string(&dev->id),
dev->enabled ? "enabled" : "disabled",
@@ -1093,18 +1123,20 @@
* @param bus Pointer to the bus structure.
* @param min_devfn Minimum devfn to look at in the scan usually 0x00.
* @param max_devfn Maximum devfn to look at in the scan usually 0xff.
- * @param max Current bus number.
- * @return The maximum bus number found, after scanning all subordinate buses.
+ * @param curr_bus Current bus number to be assigned.
+ * @return The new curr_bus, after scanning all subordinate buses.
*/
unsigned int pci_scan_bus(struct bus *bus, unsigned int min_devfn,
- unsigned int max_devfn, unsigned int max)
+ unsigned int max_devfn, unsigned int curr_bus)
{
unsigned int devfn;
struct device *old_devices;
struct device *child;
- printk(BIOS_DEBUG, "%s start bus %p, bus->dev %p\n", __func__, bus,
- bus->dev);
+ printk(BIOS_DEBUG, "%s start bus->dev %s bus %x\n", __func__,
+ bus->dev->dtsname, bus->link);
+
+#warning This check needs checking.
if (bus->dev->path.type != DEVICE_PATH_PCI_BUS)
printk(BIOS_ERR, "ERROR: pci_scan_bus called with incorrect "
"bus->dev->path.type, path is %s\n", dev_path(bus->dev));
@@ -1116,10 +1148,11 @@
printk(BIOS_DEBUG, "PCI: pci_scan_bus for bus %02x\n", bus->secondary);
#endif
+ /* Remove children of the bus, so the enumeration starts empty. */
old_devices = bus->children;
- printk(BIOS_DEBUG, "%s: old_devices %p, dev for this bus %p (%s)\n",
- __func__, old_devices, bus->dev, bus->dev->dtsname);
- bus->children = 0;
+ printk(BIOS_DEBUG, "%s: old_devices %s, dev for this bus %s\n",
+ __func__, old_devices?old_devices->dtsname:"NULL", bus->dev->dtsname);
+ bus->children = NULL;
post_code(POST_STAGE2_PCISCANBUS_ENTER);
printk(BIOS_SPEW, "PCI: scan devfn 0x%x to 0x%x\n", min_devfn,
@@ -1131,17 +1164,18 @@
struct device *dev;
printk(BIOS_SPEW, "PCI: devfn 0x%x\n", devfn);
- /* First thing setup the device structure. */
- dev = pci_scan_get_dev(&old_devices, devfn);
+ /* First thing look in the device tree. */
+ dev = pci_get_dev(&old_devices, devfn);
printk(BIOS_SPEW,
- "PCI: pci_scan_bus pci_scan_get_dev returns dev %s\n",
+ "PCI: pci_scan_bus pci_get_dev returns dev %s\n",
dev ? dev->dtsname : "None (no dev in tree yet)");
+
/* See if a device is present and setup the device structure. */
dev = pci_probe_dev(dev, bus, devfn);
printk(BIOS_SPEW,
- "PCI: pci_scan_bus pci_probe_dev returns dev %p(%s)\n",
- dev, dev ? dev->dtsname : "None (not found)");
+ "PCI: pci_scan_bus pci_probe_dev returns dev %s\n",
+ dev ? dev->dtsname : "None (no response)");
/* If this is not a multi function device, or the device is
* not present don't waste time probing another function.
@@ -1158,9 +1192,8 @@
printk(BIOS_SPEW, "PCI: Done for loop\n");
post_code(POST_STAGE2_PCISCANBUS_DONEFORLOOP);
- /* Die if any leftover static devices are are found.
- * There's probably a problem in the Config.lb.
- * TODO: No more Config.lb in coreboot-v3.
+ /* Warn if any leftover static devices are are found.
+ * There's probably a problem in the device tree (dts).
*/
if (old_devices) {
struct device *left;
@@ -1175,16 +1208,17 @@
* scan the bus behind that child.
*/
for (child = bus->children; child; child = child->sibling) {
- max = dev_phase3_scan(child, max);
+ curr_bus = dev_phase3_scan(child, curr_bus);
}
/* We've scanned the bus and so we know all about what's on the other
* side of any bridges that may be on this bus plus any devices.
* Return how far we've got finding sub-buses.
*/
- printk(BIOS_DEBUG, "PCI: pci_scan_bus returning with max=%03x\n", max);
+ printk(BIOS_DEBUG, "PCI: pci_scan_bus returning with curr_bus=%03x\n",
+ curr_bus);
post_code(POST_STAGE2_PCISCANBUS_EXIT);
- return max;
+ return curr_bus;
}
/**
@@ -1194,14 +1228,14 @@
* This function works for almost all chipsets (AMD K8 is the exception).
*
* @param dev The PCI domain device.
- * @param max Maximum number of devices to scan.
- * @return TODO
+ * @param max The current bus number to be assigned.
+ * @return The current bus number returned by pci_scan_bus.
*/
-unsigned int pci_domain_scan_bus(struct device *dev, unsigned int max)
+unsigned int pci_domain_scan_bus(struct device *dev, unsigned int curr_bus)
{
printk(BIOS_SPEW, "pci_domain_scan_bus: calling pci_scan_bus\n");
/* There is only one link on this device, and it is always link 0. */
- return pci_scan_bus(&dev->link[0], PCI_DEVFN(0, 0), 0xff, max);
+ return pci_scan_bus(&dev->link[0], PCI_DEVFN(0, 0), 0xff, curr_bus);
}
/**
