Re: [PATCH v7 08/15] ACPI: IORT: rename iort_node_map_rid() to make it generic

From: Lorenzo Pieralisi
Date: Fri Jan 13 2017 - 06:46:07 EST


On Wed, Jan 11, 2017 at 11:06:32PM +0800, Hanjun Guo wrote:
> iort_node_map_rid() was designed for both PCI and platform
> device, but the rid means requester id is for ITS mappings,

I do not understand what this means sorry.

> rename iort_node_map_rid() to iort_node_map_id() and update
> its argument names to make it more generic.
>

"iort_node_map_rid() was designed to take an input id (that is not
necessarily a PCI requester id) and map it to an output id (eg an SMMU
streamid or an ITS deviceid) according to the mappings provided by an
IORT node mapping entries. This means that the iort_node_map_rid() input
id is not always a PCI requester id as its name, parameters and local
variables suggest, which is misleading.

Apply the s/rid/id substitution to the iort_node_map_rid() mapping
function and its users to make sure its intended usage is clearer."

Lorenzo

> Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
> Cc: Tomasz Nowicki <tn@xxxxxxxxxxxx>
> ---
> drivers/acpi/arm64/iort.c | 30 +++++++++++++++---------------
> 1 file changed, 15 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index 208eac9..069a690 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -355,11 +355,11 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
> 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)
> +static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
> + u32 id_in, u32 *id_out,
> + u8 type_mask)
> {
> - u32 rid = rid_in;
> + u32 id = id_in;
>
> /* Parse the ID mapping tree to find specified node type */
> while (node) {
> @@ -367,8 +367,8 @@ static struct acpi_iort_node *iort_node_map_rid(struct acpi_iort_node *node,
> int i;
>
> if (IORT_TYPE_MASK(node->type) & type_mask) {
> - if (rid_out)
> - *rid_out = rid;
> + if (id_out)
> + *id_out = id;
> return node;
> }
>
> @@ -385,9 +385,9 @@ static struct acpi_iort_node *iort_node_map_rid(struct acpi_iort_node *node,
> goto fail_map;
> }
>
> - /* Do the RID translation */
> + /* Do the ID translation */
> for (i = 0; i < node->mapping_count; i++, map++) {
> - if (!iort_id_map(map, node->type, rid, &rid))
> + if (!iort_id_map(map, node->type, id, &id))
> break;
> }
>
> @@ -399,9 +399,9 @@ static struct acpi_iort_node *iort_node_map_rid(struct acpi_iort_node *node,
> }
>
> fail_map:
> - /* Map input RID to output RID unchanged on mapping failure*/
> - if (rid_out)
> - *rid_out = rid_in;
> + /* Map input ID to output ID unchanged on mapping failure */
> + if (id_out)
> + *id_out = id_in;
>
> return NULL;
> }
> @@ -439,7 +439,7 @@ u32 iort_msi_map_rid(struct device *dev, u32 req_id)
> if (!node)
> return req_id;
>
> - iort_node_map_rid(node, req_id, &dev_id, IORT_MSI_TYPE);
> + iort_node_map_id(node, req_id, &dev_id, IORT_MSI_TYPE);
> return dev_id;
> }
>
> @@ -462,7 +462,7 @@ static int iort_dev_find_its_id(struct device *dev, u32 req_id,
> if (!node)
> return -ENXIO;
>
> - node = iort_node_map_rid(node, req_id, NULL, IORT_MSI_TYPE);
> + node = iort_node_map_id(node, req_id, NULL, IORT_MSI_TYPE);
> if (!node)
> return -ENXIO;
>
> @@ -591,8 +591,8 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev)
> if (!node)
> return NULL;
>
> - parent = iort_node_map_rid(node, rid, &streamid,
> - IORT_IOMMU_TYPE);
> + parent = iort_node_map_id(node, rid, &streamid,
> + IORT_IOMMU_TYPE);
>
> ops = iort_iommu_xlate(dev, parent, streamid);
>
> --
> 1.9.1
>