On Wed, Mar 29, 2023 at 12:10 PM Sakari Ailus
<sakari.ailus@xxxxxxxxxxxxxxx> wrote:
>
> Prepare generating software nodes for information parsed from ACPI _CRS for
> CSI-2 as well as MIPI DisCo for Imaging spec. The software nodes are
> compliant with existing ACPI or DT definitions and are parsed by relevant
> drivers without changes.
>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> ---
> drivers/acpi/internal.h | 3 +
> drivers/acpi/mipi.c | 358 +++++++++++++++++++++++++++++++++++++++-
> drivers/acpi/scan.c | 21 ++-
> include/acpi/acpi_bus.h | 70 ++++++++
> 4 files changed, 449 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index aa5f9c69dbbe..1634a177c75e 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -304,9 +304,12 @@ static inline void acpi_init_lpit(void) { }
> ACPI _CRS CSI2 and MIPI DisCo for Imaging conversion
> -------------------------------------------------------------------------- */
>
> +#define MIPI_IMG_PORT_PREFIX "mipi-img-port-"
> +
> void acpi_crs_csi2_swnodes_del_free(void);
> void acpi_bus_scan_check_crs_csi2(acpi_handle handle, struct acpi_scan_context *ctx);
> void acpi_bus_scan_crs_csi2_release(struct list_head *crs_csi2_handles);
> void acpi_bus_scan_crs_csi2(struct acpi_scan_context_csi2 *ctx);
> +void acpi_init_swnodes(struct acpi_device *device);
>
> #endif /* _ACPI_INTERNAL_H_ */
> diff --git a/drivers/acpi/mipi.c b/drivers/acpi/mipi.c
> index d719c879eb83..03079f78bd2c 100644
> --- a/drivers/acpi/mipi.c
> +++ b/drivers/acpi/mipi.c
> @@ -3,7 +3,8 @@
> * MIPI DisCo for Imaging support.
> *
> * Support MIPI DisCo for Imaging by parsing ACPI _CRS CSI2 records and DisCo
> - * for Imaging data structures.
> + * for Imaging data structures and generating nodes and properties using
> + * software nodes compliant with DT definitions of the similar scope.
> *
> * Also see <URL:https://www.mipi.org/specifications/mipi-disco-imaging>.
> *
> @@ -20,6 +21,8 @@
> #include <linux/sort.h>
> #include <linux/string.h>
>
> +#include <media/v4l2-fwnode.h>
> +
> #include "internal.h"
>
> /* Temporary ACPI device handle to software node data structure mapping */
> @@ -31,6 +34,18 @@ struct crs_csi2_swnodes {
>
> static LIST_HEAD(crs_csi2_swnodes);
>
> +/* Obtain pre-allocated software nodes for an ACPI device handle */
> +static struct acpi_device_software_nodes *crs_csi2_swnode_get(acpi_handle handle)
> +{
> + struct crs_csi2_swnodes *swnodes;
> +
> + list_for_each_entry(swnodes, &crs_csi2_swnodes, list)
> + if (swnodes->handle == handle)
> + return swnodes->ads;
> +
> + return NULL;
> +}
> +
> static void crs_csi2_swnode_del_free(struct crs_csi2_swnodes *swnodes)
> {
> list_del(&swnodes->list);
> @@ -166,6 +181,35 @@ struct acpi_handle_ref {
>
> #define NO_CSI2_PORT (UINT_MAX - 1)
>
> +/*
> + * Return next free entry in ports array of a software nodes related to an ACPI
> + * device.
> + */
> +static unsigned int next_csi2_port_index(struct acpi_device_software_nodes *ads,
> + unsigned int port_nr)
> +{
> + unsigned int i;
> +
> + for (i = 0; i < ads->num_ports; i++) {
> + struct acpi_device_software_node_port *port = &ads->ports[i];
> +
> + if (port->port_nr == port_nr)
> + return i;
> +
> + if (port->port_nr == NO_CSI2_PORT) {
> + port->port_nr = port_nr;
> + return i;
> + }
> + }
> +
> + return NO_CSI2_PORT;
> +}
> +
> +/* Print graph port name into a buffer, return non-zero if failed. */
> +#define GRAPH_PORT_NAME(var, num) \
> + (snprintf((var), sizeof(var), SWNODE_GRAPH_PORT_NAME_FMT, (num)) >= \
> + sizeof(var))
> +
> static int crs_handle_cmp(const void *__a, const void *__b)
> {
> const struct acpi_handle_ref *a = __a, *b = __b;
> @@ -258,6 +302,9 @@ static void acpi_crs_csi2_alloc_fill_swnodes(size_t ports_count, acpi_handle han
> ports_count);
> }
>
> +#define ACPI_CRS_CSI2_PHY_TYPE_C 0
> +#define ACPI_CRS_CSI2_PHY_TYPE_D 1
> +
> /**
> * acpi_bus_scan_crs_csi2 - Construct software nodes out of ACPI _CRS CSI2
> * resource descriptors
> @@ -274,6 +321,8 @@ static void acpi_crs_csi2_alloc_fill_swnodes(size_t ports_count, acpi_handle han
> * 3. Allocate memory for swnodes each ACPI device requires later on, and
> * generate a list of such allocations.
> *
> + * 4. Set up properties for software nodes.
> + *
> * Note that struct acpi_device may not be available yet at this time.
> *
> * acpi_scan_lock in scan.c must be held when calling this function.
> @@ -339,5 +388,312 @@ void acpi_bus_scan_crs_csi2(struct acpi_scan_context_csi2 *ctx)
> this_count = this->count;
> }
>
> + /*
> + * Allocate and set up necessary software nodes for each device and set
> + * up properties from _CRS CSI2 descriptor.
> + */
> + list_for_each_entry(csi2, &ctx->crs_csi2_head, list) {
> + struct acpi_device_software_nodes *local_swnodes;
> + struct crs_csi2_instance *inst;
> +
> + local_swnodes = crs_csi2_swnode_get(csi2->handle);
> + if (WARN_ON_ONCE(!local_swnodes))
> + continue;
> +
> + list_for_each_entry(inst, &csi2->buses, list) {
> + struct acpi_device_software_nodes *remote_swnodes;
> + struct acpi_device_software_node_port *local_port;
> + struct acpi_device_software_node_port *remote_port;
> + struct software_node *local_node, *remote_node;
> + unsigned int local_index, remote_index;
> + unsigned int bus_type;
> +
> + remote_swnodes = crs_csi2_swnode_get(inst->remote_handle);
> + if (WARN_ON_ONCE(!remote_swnodes))
> + continue;
> +
> + local_index = next_csi2_port_index(local_swnodes, inst->csi2.local_port_instance);
> + remote_index = next_csi2_port_index(remote_swnodes, inst->csi2.resource_source.index);
> +
> + if (WARN_ON_ONCE(local_index >= local_swnodes->num_ports) ||
> + WARN_ON_ONCE(remote_index >= remote_swnodes->num_ports))
> + goto out_free;
> +
> + switch (inst->csi2.phy_type) {
> + case ACPI_CRS_CSI2_PHY_TYPE_C:
> + bus_type = V4L2_FWNODE_BUS_TYPE_CSI2_CPHY;
> + break;
> + case ACPI_CRS_CSI2_PHY_TYPE_D:
> + bus_type = V4L2_FWNODE_BUS_TYPE_CSI2_DPHY;
> + break;
> + default:
> + acpi_handle_info(csi2->handle,
> + "ignoring CSI-2 PHY type %u\n",
> + inst->csi2.phy_type);
> + continue;
> + }
> +
> + local_port = &local_swnodes->ports[local_index];
> + local_node = &local_swnodes->nodes[ACPI_DEVICE_SWNODE_EP(local_index)];
> + local_port->remote_ep_ref[0] = SOFTWARE_NODE_REFERENCE(local_node);
This looks odd. Is local_port pointing to its own node as a remote
endpont, or am I confused?
> + local_port->crs_csi2_local = true;
> +
> + remote_port = &remote_swnodes->ports[remote_index];
> + remote_node = &remote_swnodes->nodes[ACPI_DEVICE_SWNODE_EP(remote_index)];
> + remote_port->remote_ep_ref[0] = SOFTWARE_NODE_REFERENCE(remote_node);
Analogously here.
