diff mbox

[v9,15/16] drivers: acpi: iort: add single mapping function

Message ID 20161121100148.24769-16-lorenzo.pieralisi@arm.com (mailing list archive)
State New, archived
Headers show

Commit Message

Lorenzo Pieralisi Nov. 21, 2016, 10:01 a.m. UTC
The current IORT id mapping API requires components to provide
an input requester ID (a Bus-Device-Function (BDF) identifier for
PCI devices) to translate an input identifier to an output
identifier through an IORT range mapping.

Named components do not have an identifiable source ID therefore
their respective input/output mapping can only be defined in
IORT tables through single mappings, that provide a translation
that does not require any input identifier.

Current IORT interface for requester id mappings (iort_node_map_rid())
is not suitable for components that do not provide a requester id,
so it cannot be used for IORT named components.

Add an interface to the IORT API to enable retrieval of id
by allowing an indexed walk of the single mappings array for
a given component, therefore completing the IORT mapping API.

Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Tested-by: Tomasz Nowicki <tn@semihalf.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Tomasz Nowicki <tn@semihalf.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
---
 drivers/acpi/arm64/iort.c | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

Comments

Hanjun Guo Nov. 30, 2016, 3:22 a.m. UTC | #1
On 2016/11/21 18:01, Lorenzo Pieralisi wrote:
> The current IORT id mapping API requires components to provide
> an input requester ID (a Bus-Device-Function (BDF) identifier for
> PCI devices) to translate an input identifier to an output
> identifier through an IORT range mapping.
>
> Named components do not have an identifiable source ID therefore
> their respective input/output mapping can only be defined in
> IORT tables through single mappings, that provide a translation
> that does not require any input identifier.
>
> Current IORT interface for requester id mappings (iort_node_map_rid())
> is not suitable for components that do not provide a requester id,
> so it cannot be used for IORT named components.
>
> Add an interface to the IORT API to enable retrieval of id
> by allowing an indexed walk of the single mappings array for
> a given component, therefore completing the IORT mapping API.
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Reviewed-by: Tomasz Nowicki <tn@semihalf.com>
> Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
> Tested-by: Tomasz Nowicki <tn@semihalf.com>
> Cc: Hanjun Guo <hanjun.guo@linaro.org>
> Cc: Tomasz Nowicki <tn@semihalf.com>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> ---
>  drivers/acpi/arm64/iort.c | 39 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)

Acked-by: Hanjun Guo <hanjun.guo@linaro.org>

Thanks
Hanjun
diff mbox

Patch

diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
index f3bbef8..6aae49c 100644
--- a/drivers/acpi/arm64/iort.c
+++ b/drivers/acpi/arm64/iort.c
@@ -318,6 +318,45 @@  static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
 	return 0;
 }
 
+static
+struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
+					u32 *id_out, u8 type_mask,
+					int index)
+{
+	struct acpi_iort_node *parent;
+	struct acpi_iort_id_mapping *map;
+
+	if (!node->mapping_offset || !node->mapping_count ||
+				     index >= node->mapping_count)
+		return NULL;
+
+	map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
+			   node->mapping_offset);
+
+	/* Firmware bug! */
+	if (!map->output_reference) {
+		pr_err(FW_BUG "[node %p type %d] ID map has NULL parent reference\n",
+		       node, node->type);
+		return NULL;
+	}
+
+	parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
+			       map->output_reference);
+
+	if (!(IORT_TYPE_MASK(parent->type) & type_mask))
+		return NULL;
+
+	if (map[index].flags & ACPI_IORT_ID_SINGLE_MAPPING) {
+		if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT ||
+		    node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
+			*id_out = map[index].output_base;
+			return parent;
+		}
+	}
+
+	return NULL;
+}
+
 static struct acpi_iort_node *iort_node_map_rid(struct acpi_iort_node *node,
 						u32 rid_in, u32 *rid_out,
 						u8 type_mask)