summaryrefslogtreecommitdiffstats
path: root/src/devices/device.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/devices/device.c')
-rw-r--r--src/devices/device.c423
1 files changed, 423 insertions, 0 deletions
diff --git a/src/devices/device.c b/src/devices/device.c
new file mode 100644
index 000000000000..ffc72533892d
--- /dev/null
+++ b/src/devices/device.c
@@ -0,0 +1,423 @@
+/*
+ * (c) 1999--2000 Martin Mares <mj@suse.cz>
+ * (c) 2003 Eric Biederman <ebiederm@xmission.com>
+ */
+/* lots of mods by ron minnich (rminnich@lanl.gov), with
+ * the final architecture guidance from Tom Merritt (tjm@codegen.com)
+ * In particular, we changed from the one-pass original version to
+ * Tom's recommended multiple-pass version. I wasn't sure about doing
+ * it with multiple passes, until I actually started doing it and saw
+ * the wisdom of Tom's recommendations ...
+ *
+ * Lots of cleanups by Eric Biederman to handle bridges, and to
+ * handle resource allocation for non-pci devices.
+ */
+
+#include <console/console.h>
+#include <bitops.h>
+#include <device.h>
+#include <arch/io.h>
+#include <pci.h>
+
+/**
+ * This is the root of the device tree. A PCI tree always has
+ * one bus, bus 0. Bus 0 contains devices and bridges.
+ */
+struct device dev_root;
+/* Linked list of ALL devices */
+struct device *all_devices = 0;
+/* pointer to the last device */
+static struct device **last_dev_p = &all_devices;
+
+#define DEVICE_MEM_HIGH 0xFEC00000UL /* Reserve 20M for the system */
+#define DEVICE_IO_START 0x1000
+
+
+unsigned long device_memory_base;
+
+
+/* Append a new device to the global device chain.
+ * The chain is used to find devices once everything is set up.
+ */
+void append_device(struct device *dev)
+{
+ *last_dev_p = dev;
+ last_dev_p = &dev->next;
+}
+
+
+/** round a number to an alignment.
+ * @param val the starting value
+ * @param roundup Alignment as a power of two
+ * @returns rounded up number
+ */
+static unsigned long round(unsigned long val, unsigned long roundup)
+{
+ /* ROUNDUP MUST BE A POWER OF TWO. */
+ unsigned long inverse;
+ inverse = ~(roundup - 1);
+ val += (roundup - 1);
+ val &= inverse;
+ return val;
+}
+
+static unsigned long round_down(unsigned long val, unsigned long round_down)
+{
+ /* ROUND_DOWN MUST BE A POWER OF TWO. */
+ unsigned long inverse;
+ inverse = ~(round_down - 1);
+ val &= inverse;
+ return val;
+}
+
+
+/** Read the resources on all devices of a given bus.
+ * @param bus bus to read the resources on.
+ */
+static void read_resources(struct device *bus)
+{
+ struct device *curdev;
+
+
+ /* Walk through all of the devices and find which resources they need. */
+ for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+ if (curdev->resources > 0) {
+ continue;
+ }
+ curdev->ops->read_resources(curdev);
+ }
+}
+
+static struct device *largest_resource(struct device *bus, struct resource **result_res,
+ unsigned long type_mask, unsigned long type)
+{
+ struct device *curdev;
+ struct device *result_dev = 0;
+ struct resource *last = *result_res;
+ struct resource *result = 0;
+ int seen_last = 0;
+ for(curdev = bus->children; curdev; curdev = curdev->sibling) {
+ int i;
+ for(i = 0; i < curdev->resources; i++) {
+ struct resource *resource = &curdev->resource[i];
+ /* If it isn't the right kind of resource ignore it */
+ if ((resource->flags & type_mask) != type) {
+ continue;
+ }
+ /* Be certain to pick the successor to last */
+ if (resource == last) {
+ seen_last = 1;
+ continue;
+ }
+ if (last && (
+ (last->align < resource->align) ||
+ ((last->align == resource->align) &&
+ (last->size < resource->size)) ||
+ ((last->align == resource->align) &&
+ (last->size == resource->size) &&
+ (!seen_last)))) {
+ continue;
+ }
+ if (!result ||
+ (result->align < resource->align) ||
+ ((result->align == resource->align) &&
+ (result->size < resource->size))) {
+ result_dev = curdev;
+ result = resource;
+ }
+ }
+ }
+ *result_res = result;
+ return result_dev;
+}
+
+/* Compute allocate resources is the guts of the resource allocator.
+ *
+ * The problem.
+ * - Allocate resources locations for every device.
+ * - Don't overlap, and follow the rules of bridges.
+ * - Don't overlap with resources in fixed locations.
+ * - Be efficient so we don't have ugly strategies.
+ *
+ * The strategy.
+ * - Devices that have fixed addresses are the minority so don't
+ * worry about them too much. Instead only use part of the address
+ * space for devices with programmable addresses. This easily handles
+ * everything except bridges.
+ *
+ * - PCI devices are required to have thier sizes and their alignments
+ * equal. In this case an optimal solution to the packing problem
+ * exists. Allocate all devices from highest alignment to least
+ * alignment or vice versa. Use this.
+ *
+ * - So we can handle more than PCI run two allocation passes on
+ * bridges. The first to see how large the resources are behind
+ * the bridge, and what their alignment requirements are. The
+ * second to assign a safe address to the devices behind the
+ * bridge. This allows me to treat a bridge as just a device with
+ * a couple of resources, and not need to special case it in the
+ * allocator. Also this allows handling of other types of bridges.
+ *
+ */
+
+void compute_allocate_resource(
+ struct device *bus,
+ struct resource *bridge,
+ unsigned long type_mask,
+ unsigned long type)
+{
+ struct device *dev;
+ struct resource *resource;
+ unsigned long base;
+ unsigned long align, min_align;
+ min_align = 0;
+ base = bridge->base;
+
+ /* We want different minimum alignments for different kinds of
+ * resources. These minimums are not device type specific
+ * but resource type specific.
+ */
+ if (bridge->flags & IORESOURCE_IO) {
+ min_align = log2(DEVICE_IO_ALIGN);
+ }
+ if (bridge->flags & IORESOURCE_MEM) {
+ min_align = log2(DEVICE_MEM_ALIGN);
+ }
+
+ printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d\n",
+ bus->bus->secondary,
+ PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn),
+ (bridge->flags & IORESOURCE_IO)? "io":
+ (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
+ base, bridge->size, bridge->align, bridge->gran);
+
+ /* Make certain I have read in all of the resources */
+ read_resources(bus);
+
+ /* Remember I haven't found anything yet. */
+ resource = 0;
+
+ /* Walk through all the devices on the current bus and compute the addresses */
+ while((dev = largest_resource(bus, &resource, type_mask, type))) {
+ unsigned long size;
+ /* Do NOT I repeat do not ignore resources which have zero size.
+ * If they need to be ignored dev->read_resources should not even
+ * return them. Some resources must be set even when they have
+ * no size. PCI bridge resources are a good example of this.
+ */
+
+ /* Propogate the resource alignment to the bridge register */
+ if (resource->align > bridge->align) {
+ bridge->align = resource->align;
+ }
+
+ /* Make certain we are dealing with a good minimum size */
+ size = resource->size;
+ align = resource->align;
+ if (align < min_align) {
+ align = min_align;
+ }
+ if (resource->flags & IORESOURCE_IO) {
+ /* Don't allow potential aliases over the
+ * legacy pci expansion card addresses.
+ */
+ if ((base > 0x3ff) && ((base & 0x300) != 0)) {
+ base = (base & ~0x3ff) + 0x400;
+ }
+ /* Don't allow allocations in the VGA IO range.
+ * PCI has special cases for that.
+ */
+ else if ((base >= 0x3b0) && (base <= 0x3df)) {
+ base = 0x3e0;
+ }
+ }
+ if (((round(base, 1UL << align) + size) -1) <= resource->limit) {
+ /* base must be aligned to size */
+ base = round(base, 1UL << align);
+ resource->base = base;
+ resource->flags |= IORESOURCE_SET;
+ base += size;
+
+ printk_spew(
+ "DEV: %02x:%02x.%01x %02x * [0x%08lx - 0x%08lx] %s\n",
+ dev->bus->secondary,
+ PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn),
+ resource->index,
+ resource->base, resource->base + resource->size -1,
+ (resource->flags & IORESOURCE_IO)? "io":
+ (resource->flags & IORESOURCE_PREFETCH)? "prefmem": "mem");
+ }
+
+ }
+ /* A pci bridge resource does not need to be a power
+ * of two size, but it does have a minimum granularity.
+ * Round the size up to that minimum granularity so we
+ * know not to place something else at an address postitively
+ * decoded by the bridge.
+ */
+ bridge->size = round(base, 1UL << bridge->gran) - bridge->base;
+
+ printk_spew("DEV: %02x:%02x.%01x compute_allocate_%s: base: %08lx size: %08lx align: %d gran: %d done\n",
+ bus->bus->secondary,
+ PCI_SLOT(bus->devfn), PCI_FUNC(bus->devfn),
+ (bridge->flags & IORESOURCE_IO)? "io":
+ (bridge->flags & IORESOURCE_PREFETCH)? "prefmem" : "mem",
+ base, bridge->size, bridge->align, bridge->gran);
+
+
+}
+
+static void allocate_vga_resource(void)
+{
+ /* FIXME handle the VGA pallette snooping */
+ struct device *dev, *vga, *bus;
+ bus = vga = 0;
+ for(dev = all_devices; dev; dev = dev->next) {
+ uint32_t class_revision;
+ pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_revision);
+ if (((class_revision >> 24) == 0x03) &&
+ ((class_revision >> 16) != 0x380)) {
+ if (!vga) {
+ printk_debug("Allocating VGA resource\n");
+ vga = dev;
+ }
+ if (vga == dev) {
+ /* All legacy VGA cards have MEM & I/O space registers */
+ dev->command |= PCI_COMMAND_MEMORY | PCI_COMMAND_IO;
+ } else {
+ /* It isn't safe to enable other VGA cards */
+ dev->command &= ~(PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
+ }
+ }
+ }
+ if (vga) {
+ bus = vga->bus;
+ }
+ /* Now walk up the bridges setting the VGA enable */
+ while(bus) {
+ uint16_t ctrl;
+ pci_read_config_word(bus, PCI_BRIDGE_CONTROL, &ctrl);
+ ctrl |= PCI_BRIDGE_CTL_VGA;
+ pci_write_config_word(bus, PCI_BRIDGE_CONTROL, ctrl);
+ bus = (bus == bus->bus)? 0 : bus->bus;
+ }
+}
+
+
+/** Assign the computed resources to the bridges and devices on the bus.
+ * Recurse to any bridges found on this bus first. Then do the devices
+ * on this bus.
+ * @param bus Pointer to the structure for this bus
+ */
+void assign_resources(struct device *bus)
+{
+ struct device *curdev;
+
+ printk_debug("ASSIGN RESOURCES, bus %d\n", bus->secondary);
+
+ for (curdev = bus->children; curdev; curdev = curdev->sibling) {
+ curdev->ops->set_resources(curdev);
+ }
+ printk_debug("ASSIGNED RESOURCES, bus %d\n", bus->secondary);
+}
+
+static void enable_resources(struct device *bus)
+{
+ struct device *curdev;
+
+ /* Walk through the chain of all pci devices and enable them.
+ * This is effectively a breadth first traversal so we should
+ * not have enalbing ordering problems.
+ */
+ for (curdev = all_devices; curdev; curdev = curdev->next) {
+ uint16_t command;
+ pci_read_config_word(curdev, PCI_COMMAND, &command);
+ command |= curdev->command;
+ printk_debug("DEV: %02x:%02x.%01x cmd <- %02x\n",
+ curdev->bus->secondary,
+ PCI_SLOT(curdev->devfn), PCI_FUNC(curdev->devfn),
+ command);
+ pci_write_config_word(curdev, PCI_COMMAND, command);
+ }
+}
+
+/** Enumerate the resources on the PCI by calling pci_init
+ */
+void dev_enumerate(void)
+{
+ struct device *root;
+ printk_info("Enumerating buses...");
+ root = &dev_root;
+ if (!root->ops) {
+ root->ops = &default_pci_ops_root;
+ }
+ root->subordinate = root->ops->scan_bus(root, 0);
+ printk_info("done\n");
+}
+
+/** Starting at the root, compute what resources are needed and allocate them.
+ * I/O starts at PCI_IO_START. Since the assignment is hierarchical we
+ * set the values into the dev_root struct.
+ */
+void dev_configure(void)
+{
+ struct device *root = &dev_root;
+ printk_info("Allocating resources...");
+ printk_debug("\n");
+
+
+ root->ops->read_resources(root);
+
+ /* Make certain the io devices are allocated somewhere
+ * safe.
+ */
+ root->resource[0].base = DEVICE_IO_START;
+ root->resource[0].flags |= IORESOURCE_SET;
+ /* Now reallocate the pci resources memory with the
+ * highest addresses I can manage.
+ */
+ root->resource[1].base =
+ round_down(DEVICE_MEM_HIGH - root->resource[1].size,
+ 1UL << root->resource[1].align);
+ device_memory_base = root->resource[1].base;
+ root->resource[1].flags |= IORESOURCE_SET;
+ // now just set things into registers ... we hope ...
+ root->ops->set_resources(root);
+
+ allocate_vga_resource();
+
+ printk_info("done.\n");
+}
+
+/** Starting at the root, walk the tree and enable all devices/bridges.
+ * What really happens is computed COMMAND bits get set in register 4
+ */
+void dev_enable(void)
+{
+ printk_info("Enabling resourcess...");
+
+ /* now enable everything. */
+ enable_resources(&dev_root);
+ printk_info("done.\n");
+}
+
+/** Starting at the root, walk the tree and call a driver to
+ * do device specific setup.
+ */
+void dev_initialize(void)
+{
+ struct device *dev;
+
+ printk_info("Initializing devices...\n");
+ for (dev = all_devices; dev; dev = dev->next) {
+ if (dev->ops->init) {
+ printk_debug("PCI: %02x:%02x.%01x init\n",
+ dev->bus->secondary,
+ PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
+ dev->ops->init(dev);
+ }
+ }
+ printk_info("Devices initialized\n");
+}
+
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-27 07:10:19 +0000