[S] Change in coreboot[main]: device/Kconfig: Add an option to allocate above 4G by default

[Arthur Heymans (Code Review)]

Arthur Heymans has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/78331?usp=email )

Change subject: device/Kconfig: Add an option to allocate above 4G by default
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device/Kconfig: Add an option to allocate above 4G by default

Signed-off-by: Arthur Heymans 
Change-Id: I01218a8a3efc4a5f8ba344808949ca6b8898525f
---
M src/device/Kconfig
M src/device/resource_allocator_v4.c
2 files changed, 12 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/31/78331/1

diff --git a/src/device/Kconfig b/src/device/Kconfig
index 8c6c734..29d7a17 100644
--- a/src/device/Kconfig
+++ b/src/device/Kconfig
@@ -1004,6 +1004,15 @@
      undeclared resources. EDK2 is currently reported to also have
      problems on some platforms, at least with Intel's IGD.

+config RESOURCE_IGNORE_FLAG_IORESOURCE_ABOVE_4G
+	bool
+	default n if ARCH_X86
+	default y
+	help
+	  Don't limit mem resources to 4G, but to their actual limit.
+	  This can break both coreboot and the payload if they try to
+	  access resources above 4G in 32bit mode.
+
 config XHCI_UTILS
    def_bool n
    help
diff --git a/src/device/resource_allocator_v4.c b/src/device/resource_allocator_v4.c
index c3132f4..872e788 100644
--- a/src/device/resource_allocator_v4.c
+++ b/src/device/resource_allocator_v4.c
@@ -84,6 +84,9 @@

static resource_t effective_limit(const struct resource *const res)
 {
+	if (CONFIG(RESOURCE_IGNORE_FLAG_IORESOURCE_ABOVE_4G))
+		return res->limit;
+
    /* Always allow bridge resources above 4G. */
    if (res->flags & IORESOURCE_BRIDGE)
    	return res->limit;