diff options
Diffstat (limited to 'zephyr/drivers/cros_cbi/cros_cbi_fw_config.c')
| -rw-r--r-- | zephyr/drivers/cros_cbi/cros_cbi_fw_config.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/zephyr/drivers/cros_cbi/cros_cbi_fw_config.c b/zephyr/drivers/cros_cbi/cros_cbi_fw_config.c new file mode 100644 index 0000000000..2eacbcf6d4 --- /dev/null +++ b/zephyr/drivers/cros_cbi/cros_cbi_fw_config.c @@ -0,0 +1,189 @@ +/* Copyright 2022 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#include <drivers/cros_cbi.h> +#include <logging/log.h> + +#include "cros_board_info.h" +#include "cros_cbi_ssfc.h" +#include "cros_cbi_common.h" + +LOG_MODULE_REGISTER(cros_cbi_fw_config, LOG_LEVEL_ERR); + +/* + * Validation macros. + * These are moved out of header files to avoid exposing them outside + * this file scope. + */ + +/* + * Statically count the number of bits set in a 32 bit constant expression. + */ +#define BIT_SET(v, b) ((v >> b) & 1) +#define BIT_COUNT(v) \ + (BIT_SET(v, 31) + BIT_SET(v, 30) + BIT_SET(v, 29) + BIT_SET(v, 28) + \ + BIT_SET(v, 27) + BIT_SET(v, 26) + BIT_SET(v, 25) + BIT_SET(v, 24) + \ + BIT_SET(v, 23) + BIT_SET(v, 22) + BIT_SET(v, 21) + BIT_SET(v, 20) + \ + BIT_SET(v, 19) + BIT_SET(v, 18) + BIT_SET(v, 17) + BIT_SET(v, 16) + \ + BIT_SET(v, 15) + BIT_SET(v, 14) + BIT_SET(v, 13) + BIT_SET(v, 12) + \ + BIT_SET(v, 11) + BIT_SET(v, 10) + BIT_SET(v, 9) + BIT_SET(v, 8) + \ + BIT_SET(v, 7) + BIT_SET(v, 6) + BIT_SET(v, 5) + BIT_SET(v, 4) + \ + BIT_SET(v, 3) + BIT_SET(v, 2) + BIT_SET(v, 1) + BIT_SET(v, 0)) + +/* + * Shorthand macros to access properties on the field node. + */ +#define FW_START(id) DT_PROP(id, start) +#define FW_SIZE(id) DT_PROP(id, size) + +/* + * Calculate the mask of the field from the size. + */ +#define FW_MASK(id) ((1 << FW_SIZE(id)) - 1) + +/* + * Calculate the mask and shift it to the correct start bit. + */ +#define FW_SHIFT_MASK(id) (FW_MASK(id) << FW_START(id)) + +/* + * For a child "named-cbi-fw-config-value" node, retrieve the + * size of the parent field this value is associated with. + */ +#define FW_PARENT_SIZE(id) DT_PROP(DT_PARENT(id), size) + +/* + * Validation check to ensure total field sizes do not exceed 32 bits. + * The FOREACH loop is nested, one to iterate through all the + * fw_config nodes, and another for the child field nodes in each + * of the fw_config nodes. + */ +#define PLUS_FIELD_SIZE(inst) + DT_PROP(inst, size) +#define FIELDS_ALL_SIZE(inst) \ + DT_FOREACH_CHILD_STATUS_OKAY(inst, PLUS_FIELD_SIZE) + +/* + * Result is the sum of all the field sizes. + */ +#define TOTAL_FW_CONFIG_NODES_SIZE \ + (0 DT_FOREACH_STATUS_OKAY(CBI_FW_CONFIG_COMPAT, FIELDS_ALL_SIZE)) + +BUILD_ASSERT(TOTAL_FW_CONFIG_NODES_SIZE <= 32, + "CBI FW Config is bigger than 32 bits"); + +/* + * Validation check to ensure there are no overlapping fields. + * OR together all the masks, count the bits, and compare against the + * total of the sizes. They should match. + */ +#define OR_FIELD_SHIFT_MASK(id) | FW_SHIFT_MASK(id) +#define FIELDS_ALL_BITS_SET(inst) \ + DT_FOREACH_CHILD_STATUS_OKAY(inst, OR_FIELD_SHIFT_MASK) + +#define TOTAL_BITS_SET \ + (0 DT_FOREACH_STATUS_OKAY(CBI_FW_CONFIG_COMPAT, \ + FIELDS_ALL_BITS_SET)) + +BUILD_ASSERT(BIT_COUNT(TOTAL_BITS_SET) == TOTAL_FW_CONFIG_NODES_SIZE, + "CBI FW Config has overlapping fields"); + +/* + * Validation for each assigned field values. + * The value must fit within the parent's defined size. + */ +#define FW_VALUE_BUILD_ASSERT(inst) \ + BUILD_ASSERT(DT_PROP(inst, value) < \ + (1 << FW_PARENT_SIZE(inst)), \ + "CBI FW Config value too big"); + +DT_FOREACH_STATUS_OKAY(CBI_FW_CONFIG_VALUE_COMPAT, FW_VALUE_BUILD_ASSERT) + +/* + * Define union bit fields based on the device tree entries. Example: + * cbi-fw-config { + * compatible = "named-cbi-fw-config"; + * + * fan { + * enum-name = "FW_CONFIG_FAN"; + * start = <0>; + * size = <1>; + * fan_present { + * enum-name = "FW_FAN_PRESENT" + * compatible = "named-cbi-fw-config-value"; + * value = <1>; + * }; + * }; + * }; + * + * Creates + * switch (field_id) { + * case FW_CONFIG_FAN: + * return (value >> 0) & 1; + * ... + * } + * + */ + +/* + * The per-field case statement. + * Extract the field value using the start and size. + */ +#define FW_FIELD_CASE(id, cached, value) \ + case CBI_FW_CONFIG_ENUM(id): \ + *value = (cached >> FW_START(id)) & FW_MASK(id); \ + break; + +/* + * Create a case for every child of this "named-cbi-fw-config" node. + */ +#define FW_FIELD_NODES(inst, cached, value) \ + DT_FOREACH_CHILD_STATUS_OKAY_VARGS(inst, FW_FIELD_CASE, cached, value) + +void cros_cbi_fw_config_init(const struct device *dev) +{ + struct cros_cbi_data *data = (struct cros_cbi_data *)(dev->data); + + if (cbi_get_fw_config(&data->cached_fw_config) != EC_SUCCESS) + /* + * Missing fw config will defaults to all zeros. + */ + data->cached_fw_config = 0; + + LOG_INF("Read CBI FW Config : 0x%08X\n", data->cached_fw_config); +} + +static int cros_cbi_fw_config_get_field( + uint32_t cached_fw_config, + enum cbi_fw_config_field_id field_id, + uint32_t *value) +{ + switch (field_id) { + /* + * Iterate through all the the "named-cbi-fw-config" nodes, + * and create cases for all of their child nodes. + */ + DT_FOREACH_STATUS_OKAY_VARGS(CBI_FW_CONFIG_COMPAT, + FW_FIELD_NODES, + cached_fw_config, + value) + default: + return -EINVAL; + } + return 0; +} + +int cros_cbi_ec_get_fw_config(const struct device *dev, + enum cbi_fw_config_field_id field_id, + uint32_t *value) +{ + struct cros_cbi_data *data = (struct cros_cbi_data *)(dev->data); + int rc; + + rc = cros_cbi_fw_config_get_field(data->cached_fw_config, + field_id, value); + if (rc) + LOG_ERR("CBI FW Config field not found: %d\n", field_id); + return rc; +} |