// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
 *
 * Module Name: rslist - Linked list utilities
 *
 ******************************************************************************/

#include <acpi/acpi.h>
#include "accommon.h"
#include "acresrc.h"

#define _COMPONENT          ACPI_RESOURCES
ACPI_MODULE_NAME("rslist")

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_convert_aml_to_resources
 *
 * PARAMETERS:  acpi_walk_aml_callback
 *              resource_ptr            - Pointer to the buffer that will
 *                                        contain the output structures
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Convert an AML resource to an internal representation of the
 *              resource that is aligned and easier to access.
 *
 ******************************************************************************/
acpi_status
acpi_rs_convert_aml_to_resources(u8 * aml,
                                 u32 length,
                                 u32 offset, u8 resource_index, void **context)
{
        struct acpi_resource **resource_ptr =
            ACPI_CAST_INDIRECT_PTR(struct acpi_resource, context);
        struct acpi_resource *resource;
        union aml_resource *aml_resource;
        struct acpi_rsconvert_info *conversion_table;
        acpi_status status;

        ACPI_FUNCTION_TRACE(rs_convert_aml_to_resources);

        /*
         * Check that the input buffer and all subsequent pointers into it
         * are aligned on a native word boundary. Most important on IA64
         */
        resource = *resource_ptr;
        if (ACPI_IS_MISALIGNED(resource)) {
                ACPI_WARNING((AE_INFO,
                              "Misaligned resource pointer %p", resource));
        }

        /* Get the appropriate conversion info table */

        aml_resource = ACPI_CAST_PTR(union aml_resource, aml);

        if (acpi_ut_get_resource_type(aml) == ACPI_RESOURCE_NAME_SERIAL_BUS) {
                if (aml_resource->common_serial_bus.type >
                    AML_RESOURCE_MAX_SERIALBUSTYPE) {
                        conversion_table = NULL;
                } else {
                        /* This is an I2C, SPI, UART, or CSI2 serial_bus descriptor */

                        conversion_table =
                            acpi_gbl_convert_resource_serial_bus_dispatch
                            [aml_resource->common_serial_bus.type];
                }
        } else {
                conversion_table =
                    acpi_gbl_get_resource_dispatch[resource_index];
        }

        if (!conversion_table) {
                ACPI_ERROR((AE_INFO,
                            "Invalid/unsupported resource descriptor: Type 0x%2.2X",
                            resource_index));
                return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
        }

        /* Convert the AML byte stream resource to a local resource struct */

        status =
            acpi_rs_convert_aml_to_resource(resource, aml_resource,
                                            conversion_table);
        if (ACPI_FAILURE(status)) {
                ACPI_EXCEPTION((AE_INFO, status,
                                "Could not convert AML resource (Type 0x%X)",
                                *aml));
                return_ACPI_STATUS(status);
        }

        if (!resource->length) {
                ACPI_EXCEPTION((AE_INFO, status,
                                "Zero-length resource returned from RsConvertAmlToResource"));
        }

        ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
                          "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
                          acpi_ut_get_resource_type(aml), length,
                          resource->length));

        /* Point to the next structure in the output buffer */

        *resource_ptr = ACPI_NEXT_RESOURCE(resource);
        return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_convert_resources_to_aml
 *
 * PARAMETERS:  resource            - Pointer to the resource linked list
 *              aml_size_needed     - Calculated size of the byte stream
 *                                    needed from calling acpi_rs_get_aml_length()
 *                                    The size of the output_buffer is
 *                                    guaranteed to be >= aml_size_needed
 *              output_buffer       - Pointer to the buffer that will
 *                                    contain the byte stream
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes the resource linked list and parses it, creating a
 *              byte stream of resources in the caller's output buffer
 *
 ******************************************************************************/

acpi_status
acpi_rs_convert_resources_to_aml(struct acpi_resource *resource,
                                 acpi_size aml_size_needed, u8 * output_buffer)
{
        u8 *aml = output_buffer;
        u8 *end_aml = output_buffer + aml_size_needed;
        struct acpi_rsconvert_info *conversion_table;
        acpi_status status;

        ACPI_FUNCTION_TRACE(rs_convert_resources_to_aml);

        /* Walk the resource descriptor list, convert each descriptor */

        while (aml < end_aml) {

                /* Validate the (internal) Resource Type */

                if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
                        ACPI_ERROR((AE_INFO,
                                    "Invalid descriptor type (0x%X) in resource list",
                                    resource->type));
                        return_ACPI_STATUS(AE_BAD_DATA);
                }

                /* Sanity check the length. It must not be zero, or we loop forever */

                if (!resource->length) {
                        ACPI_ERROR((AE_INFO,
                                    "Invalid zero length descriptor in resource list\n"));
                        return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
                }

                /* Perform the conversion */

                if (resource->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
                        if (resource->data.common_serial_bus.type >
                            AML_RESOURCE_MAX_SERIALBUSTYPE) {
                                conversion_table = NULL;
                        } else {
                                /* This is an I2C, SPI, UART or CSI2 serial_bus descriptor */

                                conversion_table =
                                    acpi_gbl_convert_resource_serial_bus_dispatch
                                    [resource->data.common_serial_bus.type];
                        }
                } else {
                        conversion_table =
                            acpi_gbl_set_resource_dispatch[resource->type];
                }

                if (!conversion_table) {
                        ACPI_ERROR((AE_INFO,
                                    "Invalid/unsupported resource descriptor: Type 0x%2.2X",
                                    resource->type));
                        return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
                }

                status = acpi_rs_convert_resource_to_aml(resource,
                                                         ACPI_CAST_PTR(union
                                                                       aml_resource,
                                                                       aml),
                                                         conversion_table);
                if (ACPI_FAILURE(status)) {
                        ACPI_EXCEPTION((AE_INFO, status,
                                        "Could not convert resource (type 0x%X) to AML",
                                        resource->type));
                        return_ACPI_STATUS(status);
                }

                /* Perform final sanity check on the new AML resource descriptor */

                status =
                    acpi_ut_validate_resource(NULL,
                                              ACPI_CAST_PTR(union aml_resource,
                                                            aml), NULL);
                if (ACPI_FAILURE(status)) {
                        return_ACPI_STATUS(status);
                }

                /* Check for end-of-list, normal exit */

                if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {

                        /* An End Tag indicates the end of the input Resource Template */

                        return_ACPI_STATUS(AE_OK);
                }

                /*
                 * Extract the total length of the new descriptor and set the
                 * Aml to point to the next (output) resource descriptor
                 */
                aml += acpi_ut_get_descriptor_length(aml);

                /* Point to the next input resource descriptor */

                resource = ACPI_NEXT_RESOURCE(resource);
        }

        /* Completed buffer, but did not find an end_tag resource descriptor */

        return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
}