From 38aafa329f4529dfc84b4c49d25cc5eb7f8fe400 Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Sun, 4 Sep 2022 22:20:21 +0200 Subject: 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 Reviewed-on: https://review.coreboot.org/c/coreboot/+/67329 Reviewed-by: Angel Pons Tested-by: build bot (Jenkins) Reviewed-by: Lean Sheng Tan Reviewed-by: Martin L Roth --- src/device/Kconfig | 2 +- src/device/resource_allocator_v4.c | 194 +++++++++++++++++++++++++++++++------ 2 files changed, 166 insertions(+), 30 deletions(-) (limited to 'src') diff --git a/src/device/Kconfig b/src/device/Kconfig index 8d10c17f4e..af9beb32f5 100644 --- a/src/device/Kconfig +++ b/src/device/Kconfig @@ -934,7 +934,7 @@ config RESOURCE_ALLOCATOR_V4 above 4G boundary as well. config RESOURCE_ALLOCATION_TOP_DOWN - bool "Allocate resources from top down" if !PCIEXP_HOTPLUG_PREFETCH_MEM_ABOVE_4G + bool "Allocate resources from top down" default y depends on RESOURCE_ALLOCATOR_V4 diff --git a/src/device/resource_allocator_v4.c b/src/device/resource_allocator_v4.c index 03cec3e673..222f1e9a47 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 -#include #include #include #include @@ -24,17 +22,6 @@ static bool dev_has_children(const struct device *dev) 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 @@ static void update_bridge_resource(const struct device *bridge, struct resource * 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 @@ static unsigned char get_alignment_by_resource_type(const struct resource *res) 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 @@ static void allocate_child_resources(struct bus *bus, struct memranges *ranges, 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 @@ static void constrain_domain_resources(const struct device *domain, struct memra /* * 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 constrain_domain_resources(const struct device *domain, struct memra 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 @@ static void allocate_domain_resources(const struct device *domain) * 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); } -- cgit v1.2.3