Revert "allocator_v4: Treat above 4G resources more natively"
This reverts commit 117e436115484f0ce184114b22b716616592e77e.
Depends on top-down allocation to keep the behavior to place
hot-plug reservations above 4G. The latter was merged prema-
turely, though.
Change-Id: I5721cb84b29fc42240dff94f49a94461d88e7fbc
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67329
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Lean Sheng Tan <sheng.tan@9elements.com>
Reviewed-by: Martin L Roth <gaumless@gmail.com>
diff --git a/src/device/resource_allocator_v4.c b/src/device/resource_allocator_v4.c
index 03cec3e..222f1e9 100644
--- a/src/device/resource_allocator_v4.c
+++ b/src/device/resource_allocator_v4.c
@@ -1,7 +1,5 @@
/* SPDX-License-Identifier: GPL-2.0-only */
-#include <stdint.h>
-#include <commonlib/helpers.h>
#include <console/console.h>
#include <device/device.h>
#include <memrange.h>
@@ -24,17 +22,6 @@
return bus && bus->children;
}
-static resource_t effective_limit(const struct resource *const res)
-{
- /* Always allow bridge resources above 4G. */
- if (res->flags & IORESOURCE_BRIDGE)
- return res->limit;
-
- const resource_t quirk_4g_limit =
- res->flags & IORESOURCE_ABOVE_4G ? UINT64_MAX : UINT32_MAX;
- return MIN(res->limit, quirk_4g_limit);
-}
-
#define res_printk(depth, str, ...) printk(BIOS_DEBUG, "%*c"str, depth, ' ', __VA_ARGS__)
/*
@@ -108,8 +95,22 @@
* starts at the domain level takes into account all these constraints
* thus working on a global view.
*/
- if (effective_limit(child_res) < bridge_res->limit)
- bridge_res->limit = effective_limit(child_res);
+ if (child_res->limit < bridge_res->limit)
+ bridge_res->limit = child_res->limit;
+
+ /*
+ * Propagate the downstream resource request to allocate above 4G
+ * boundary to upstream bridge resource. This ensures that during
+ * pass 2, the resource allocator at domain level has a global view
+ * of all the downstream device requirements and thus address space
+ * is allocated as per updated flags in the bridge resource.
+ *
+ * Since the bridge resource is a single window, all the downstream
+ * resources of this bridge resource will be allocated in space above
+ * the 4G boundary.
+ */
+ if (child_res->flags & IORESOURCE_ABOVE_4G)
+ bridge_res->flags |= IORESOURCE_ABOVE_4G;
/*
* Alignment value of 0 means that the child resource has no alignment
@@ -222,6 +223,129 @@
die("Unexpected resource type: flags(%d)!\n", res->flags);
}
+/*
+ * If the resource is NULL or if the resource is not assigned, then it
+ * cannot be used for allocation for downstream devices.
+ */
+static bool is_resource_invalid(const struct resource *res)
+{
+ return (res == NULL) || !(res->flags & IORESOURCE_ASSIGNED);
+}
+
+static void initialize_domain_io_resource_memranges(struct memranges *ranges,
+ const struct resource *res,
+ unsigned long memrange_type)
+{
+ memranges_insert(ranges, res->base, res->limit - res->base + 1, memrange_type);
+}
+
+static void initialize_domain_mem_resource_memranges(struct memranges *ranges,
+ const struct resource *res,
+ unsigned long memrange_type)
+{
+ resource_t res_base;
+ resource_t res_limit;
+
+ const resource_t limit_4g = 0xffffffff;
+
+ res_base = res->base;
+ res_limit = res->limit;
+
+ /*
+ * Split the resource into two separate ranges if it crosses the 4G
+ * boundary. Memrange type is set differently to ensure that memrange
+ * does not merge these two ranges. For the range above 4G boundary,
+ * given memrange type is ORed with IORESOURCE_ABOVE_4G.
+ */
+ if (res_base <= limit_4g) {
+
+ resource_t range_limit;
+
+ /* Clip the resource limit at 4G boundary if necessary. */
+ range_limit = MIN(res_limit, limit_4g);
+ memranges_insert(ranges, res_base, range_limit - res_base + 1, memrange_type);
+
+ /*
+ * If the resource lies completely below the 4G boundary, nothing more
+ * needs to be done.
+ */
+ if (res_limit <= limit_4g)
+ return;
+
+ /*
+ * If the resource window crosses the 4G boundary, then update res_base
+ * to add another entry for the range above the boundary.
+ */
+ res_base = limit_4g + 1;
+ }
+
+ if (res_base > res_limit)
+ return;
+
+ /*
+ * If resource lies completely above the 4G boundary or if the resource
+ * was clipped to add two separate ranges, the range above 4G boundary
+ * has the resource flag IORESOURCE_ABOVE_4G set. This allows domain to
+ * handle any downstream requests for resource allocation above 4G
+ * differently.
+ */
+ memranges_insert(ranges, res_base, res_limit - res_base + 1,
+ memrange_type | IORESOURCE_ABOVE_4G);
+}
+
+/*
+ * This function initializes memranges for domain device. If the
+ * resource crosses 4G boundary, then this function splits it into two
+ * ranges -- one for the window below 4G and the other for the window
+ * above 4G. The latter range has IORESOURCE_ABOVE_4G flag set to
+ * satisfy resource requests from downstream devices for allocations
+ * above 4G.
+ */
+static void initialize_domain_memranges(struct memranges *ranges, const struct resource *res,
+ unsigned long memrange_type)
+{
+ unsigned char align = get_alignment_by_resource_type(res);
+
+ memranges_init_empty_with_alignment(ranges, NULL, 0, align);
+
+ if (is_resource_invalid(res))
+ return;
+
+ if (res->flags & IORESOURCE_IO)
+ initialize_domain_io_resource_memranges(ranges, res, memrange_type);
+ else
+ initialize_domain_mem_resource_memranges(ranges, res, memrange_type);
+}
+
+/*
+ * This function initializes memranges for bridge device. Unlike domain,
+ * bridge does not need to care about resource window crossing 4G
+ * boundary. This is handled by the resource allocator at domain level
+ * to ensure that all downstream bridges are allocated space either
+ * above or below 4G boundary as per the state of IORESOURCE_ABOVE_4G
+ * for the respective bridge resource.
+ *
+ * So, this function creates a single range of the entire resource
+ * window available for the bridge resource. Thus all downstream
+ * resources of the bridge for the given resource type get allocated
+ * space from the same window. If there is any downstream resource of
+ * the bridge which requests allocation above 4G, then all other
+ * downstream resources of the same type under the bridge get allocated
+ * above 4G.
+ */
+static void initialize_bridge_memranges(struct memranges *ranges, const struct resource *res,
+ unsigned long memrange_type)
+{
+ unsigned char align = get_alignment_by_resource_type(res);
+
+ memranges_init_empty_with_alignment(ranges, NULL, 0, align);
+
+ if (is_resource_invalid(res))
+ return;
+
+ memranges_insert(ranges, res->base, res->limit - res->base + 1, memrange_type);
+}
+
static void print_resource_ranges(const struct device *dev, const struct memranges *ranges)
{
const struct range_entry *r;
@@ -259,13 +383,12 @@
if (!resource->size)
continue;
- if (memranges_steal(ranges, effective_limit(resource), resource->size,
- resource->align, type_match, &resource->base,
- allocate_top_down) == false) {
+ if (memranges_steal(ranges, resource->limit, resource->size, resource->align,
+ type_match, &resource->base, allocate_top_down) == false) {
printk(BIOS_ERR, " ERROR: Resource didn't fit!!! ");
printk(BIOS_DEBUG, " %s %02lx * size: 0x%llx limit: %llx %s\n",
- dev_path(dev), resource->index, resource->size,
- effective_limit(resource), resource2str(resource));
+ dev_path(dev), resource->index,
+ resource->size, resource->limit, resource2str(resource));
continue;
}
@@ -348,8 +471,8 @@
/*
* This function creates a list of memranges of given type using the
- * resource that is provided. If the given resource is unassigned or if
- * the resource window size is 0, then it creates an empty list. This
+ * resource that is provided. If the given resource is NULL or if the
+ * resource window size is 0, then it creates an empty list. This
* results in resource allocation for that resource type failing for
* all downstream devices since there is nothing to allocate from.
*
@@ -363,17 +486,16 @@
static void setup_resource_ranges(const struct device *dev, const struct resource *res,
unsigned long type, struct memranges *ranges)
{
- const unsigned char alignment = get_alignment_by_resource_type(res);
-
printk(BIOS_DEBUG, "%s %s: base: %llx size: %llx align: %d gran: %d limit: %llx\n",
dev_path(dev), resource2str(res), res->base, res->size, res->align,
res->gran, res->limit);
- memranges_init_empty_with_alignment(ranges, NULL, 0, alignment);
- if (res->flags & IORESOURCE_ASSIGNED)
- memranges_insert(ranges, res->base, res->limit - res->base + 1, type);
- if (dev->path.type == DEVICE_PATH_DOMAIN)
+ if (dev->path.type == DEVICE_PATH_DOMAIN) {
+ initialize_domain_memranges(ranges, res, type);
constrain_domain_resources(dev, ranges, type);
+ } else {
+ initialize_bridge_memranges(ranges, res, type);
+ }
print_resource_ranges(dev, ranges);
}
@@ -486,12 +608,26 @@
* the resource allocation at domain level considers mem and prefmem
* together when finding the best fit based on the biggest resource
* requirement.
+ *
+ * However, resource requests for allocation above 4G boundary need to
+ * be handled separately if the domain resource window crosses this
+ * boundary. There is a single window for resource of type
+ * IORESOURCE_MEM. When creating memranges, this resource is split into
+ * two separate ranges -- one for the window below 4G boundary and other
+ * for the window above 4G boundary (with IORESOURCE_ABOVE_4G flag set).
+ * Thus, when allocating child resources, requests for below and above
+ * the 4G boundary are handled separately by setting the type_mask and
+ * type_match to allocate_child_resources() accordingly.
*/
res = find_domain_resource(domain, IORESOURCE_MEM);
if (res) {
setup_resource_ranges(domain, res, IORESOURCE_MEM, &ranges);
allocate_child_resources(domain->link_list, &ranges,
- IORESOURCE_TYPE_MASK, IORESOURCE_MEM);
+ IORESOURCE_TYPE_MASK | IORESOURCE_ABOVE_4G,
+ IORESOURCE_MEM);
+ allocate_child_resources(domain->link_list, &ranges,
+ IORESOURCE_TYPE_MASK | IORESOURCE_ABOVE_4G,
+ IORESOURCE_MEM | IORESOURCE_ABOVE_4G);
cleanup_resource_ranges(domain, &ranges, res);
}