[Patch v4 14/23] ACPI: Translate resource into master side address for bridge window resources

[Jiang Liu]

Add translation_offset into the result address for bridge window
resources to form the master side address.

Currently acpi_dev_resource_{ext_}address_space() are only used for
devices instead of bridges, so it won't break current users. Later
it will be used to support PCI host bridge drivers.

Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
---
 drivers/acpi/resource.c |   15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index c902c8eece81..4dc8cfb2e94e 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -205,6 +205,21 @@ static bool acpi_decode_space(struct resource_win *win,
 	res->start = attr->minimum;
 	res->end = attr->maximum;
 
+	/*
+	 * For bridges that translate addresses across the bridge,
+	 * translation_offset is the offset that must be added to the
+	 * address on the secondary side to obtain the address on the
+	 * primary side. Non-bridge devices must list 0 for all Address
+	 * Translation offset bits.
+	 */
+	if (addr->producer_consumer == ACPI_PRODUCER) {
+		res->start += attr->translation_offset;
+		res->end += attr->translation_offset;
+	} else if (attr->translation_offset) {
+		pr_debug("ACPI: translation_offset(%lld) is invalid for non-bridge device.\n",
+			 attr->translation_offset);
+	}
+
 	switch (addr->resource_type) {
 	case ACPI_MEMORY_RANGE:
 		acpi_dev_memresource_flags(res, len, wp);
-- 
1.7.10.4

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