CHROMIUM: iwl7000: mvm: read SAR BIOS table from ACPI
Read the SAR BIOS table from the ACPI and parse it into the
iwl_mvm_sar_table structure. If the table is enabled, send it to the
firmware via REDUCE_TX_POWER_CMD.
BUG=chrome-os-partner:50457
TEST=add wifi_sar="28282828282828282828" to the vpd and check that the
TX power on different chain-band combinations don't exceed 5dBm (0x28
means 5dBm). Note that this needs a coreboot that supports the
wifi_sar option.
Change-Id: I093755ecc3e260700dc6b54f6e5e7d159779212c
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
(cherry picked from commit 4f958b740a503e6e44aa2fbbd695da1162ef8457)
(squashed with commit 0f73133df4bd157680313d9f8627ed8e7fc9e277)
iwl7000-tree: 75ecfe0e9c760178c0d7dd1118faf91ba4e20a54
iwl7000-tree: 1836bc2365b81fd74dd0cbc534499731d1b9559d
Reviewed-on: https://chromium-review.googlesource.com/355450
Commit-Ready: Kirtika Ruchandani <kirtika@google.com>
Tested-by: Kirtika Ruchandani <kirtika@google.com>
Reviewed-by: Dmitry Torokhov <dtor@chromium.org>
diff --git a/drivers/net/wireless/iwl7000/iwlwifi/mvm/fw.c b/drivers/net/wireless/iwl7000/iwlwifi/mvm/fw.c
index 59f549b..2af079f 100644
--- a/drivers/net/wireless/iwl7000/iwlwifi/mvm/fw.c
+++ b/drivers/net/wireless/iwl7000/iwlwifi/mvm/fw.c
@@ -64,6 +64,7 @@
*
*****************************************************************************/
#include <net/mac80211.h>
+#include <linux/acpi.h>
#include "iwl-trans.h"
#include "iwl-op-mode.h"
@@ -939,6 +940,174 @@
sizeof(cmd), &cmd);
}
+#define ACPI_WRDS_METHOD "WRDS"
+#define ACPI_WRDS_WIFI (0x07)
+#define ACPI_WRDS_TABLE_SIZE 10
+
+struct iwl_mvm_sar_table {
+ bool enabled;
+ u8 values[ACPI_WRDS_TABLE_SIZE];
+};
+
+#ifdef CONFIG_ACPI
+static int iwl_mvm_sar_get_wrds(struct iwl_mvm *mvm, union acpi_object *wrds,
+ struct iwl_mvm_sar_table *sar_table)
+{
+ union acpi_object *data_pkg;
+ u32 i;
+
+ /* We need at least two packages, one for the revision and one
+ * for the data itself. Also check that the revision is valid
+ * (i.e. it is an integer set to 0).
+ */
+ if (wrds->type != ACPI_TYPE_PACKAGE ||
+ wrds->package.count < 2 ||
+ wrds->package.elements[0].type != ACPI_TYPE_INTEGER ||
+ wrds->package.elements[0].integer.value != 0) {
+ IWL_DEBUG_RADIO(mvm, "Unsupported wrds structure\n");
+ return -EINVAL;
+ }
+
+ /* loop through all the packages to find the one for WiFi */
+ for (i = 1; i < wrds->package.count; i++) {
+ union acpi_object *domain;
+
+ data_pkg = &wrds->package.elements[i];
+
+ /* Skip anything that is not a package with the right
+ * amount of elements (i.e. domain_type,
+ * enabled/disabled plus the sar table size.
+ */
+ if (data_pkg->type != ACPI_TYPE_PACKAGE ||
+ data_pkg->package.count != ACPI_WRDS_TABLE_SIZE + 2)
+ continue;
+
+ domain = &data_pkg->package.elements[0];
+ if (domain->type == ACPI_TYPE_INTEGER &&
+ domain->integer.value == ACPI_WRDS_WIFI)
+ break;
+
+ data_pkg = NULL;
+ }
+
+ if (!data_pkg)
+ return -ENOENT;
+
+ if (data_pkg->package.elements[1].type != ACPI_TYPE_INTEGER)
+ return -EINVAL;
+
+ sar_table->enabled = !!(data_pkg->package.elements[1].integer.value);
+
+ for (i = 0; i < ACPI_WRDS_TABLE_SIZE; i++) {
+ union acpi_object *entry;
+
+ entry = &data_pkg->package.elements[i + 2];
+ if ((entry->type != ACPI_TYPE_INTEGER) ||
+ (entry->integer.value > U8_MAX))
+ return -EINVAL;
+
+ sar_table->values[i] = entry->integer.value;
+ }
+
+ return 0;
+}
+
+static int iwl_mvm_sar_get_table(struct iwl_mvm *mvm,
+ struct iwl_mvm_sar_table *sar_table)
+{
+ acpi_handle root_handle;
+ acpi_handle handle;
+ struct acpi_buffer wrds = {ACPI_ALLOCATE_BUFFER, NULL};
+ acpi_status status;
+ int ret;
+
+ root_handle = ACPI_HANDLE(mvm->dev);
+ if (!root_handle) {
+ IWL_DEBUG_RADIO(mvm,
+ "Could not retrieve root port ACPI handle\n");
+ return -ENOENT;
+ }
+
+ /* Get the method's handle */
+ status = acpi_get_handle(root_handle, (acpi_string)ACPI_WRDS_METHOD,
+ &handle);
+ if (ACPI_FAILURE(status)) {
+ IWL_DEBUG_RADIO(mvm, "WRDS method not found\n");
+ return -ENOENT;
+ }
+
+ /* Call WRDS with no arguments */
+ status = acpi_evaluate_object(handle, NULL, NULL, &wrds);
+ if (ACPI_FAILURE(status)) {
+ IWL_DEBUG_RADIO(mvm, "WRDS invocation failed (0x%x)\n", status);
+ return -ENOENT;
+ }
+
+ ret = iwl_mvm_sar_get_wrds(mvm, wrds.pointer, sar_table);
+ kfree(wrds.pointer);
+
+ return ret;
+}
+#else /* CONFIG_ACPI */
+static int iwl_mvm_sar_get_table(struct iwl_mvm *mvm,
+ struct iwl_mvm_sar_table *sar_table)
+{
+ return -ENOENT;
+}
+#endif /* CONFIG_ACPI */
+
+static int iwl_mvm_sar_init(struct iwl_mvm *mvm)
+{
+ struct iwl_mvm_sar_table sar_table;
+ struct iwl_dev_tx_power_cmd cmd = {
+ .v2.set_mode = cpu_to_le32(IWL_TX_POWER_MODE_SET_CHAINS),
+ };
+ int ret, i, j, idx;
+
+ /* we can't do anything with the table if the FW doesn't support it */
+ if (!fw_has_api(&mvm->fw->ucode_capa,
+ IWL_UCODE_TLV_API_TX_POWER_CHAIN)) {
+ IWL_DEBUG_RADIO(mvm,
+ "FW doesn't support per-chain TX power settings.\n");
+ return 0;
+ }
+
+ ret = iwl_mvm_sar_get_table(mvm, &sar_table);
+ if (ret < 0) {
+ IWL_DEBUG_RADIO(mvm,
+ "SAR BIOS table invalid or unavailable. (%d)\n",
+ ret);
+ /* we don't fail if the table is not available */
+ return 0;
+ }
+
+ if (!sar_table.enabled)
+ return 0;
+
+ IWL_DEBUG_RADIO(mvm, "Sending REDUCE_TX_POWER_CMD per chain\n");
+
+ BUILD_BUG_ON(IWL_NUM_CHAIN_LIMITS * IWL_NUM_SUB_BANDS !=
+ ACPI_WRDS_TABLE_SIZE);
+
+ for (i = 0; i < IWL_NUM_CHAIN_LIMITS; i++) {
+ IWL_DEBUG_RADIO(mvm, " Chain[%d]:\n", i);
+ for (j = 0; j < IWL_NUM_SUB_BANDS; j++) {
+ idx = (i * IWL_NUM_SUB_BANDS) + j;
+ cmd.per_chain_restriction[i][j] =
+ cpu_to_le16(sar_table.values[idx]);
+ IWL_DEBUG_RADIO(mvm, " Band[%d] = %d * .125dBm\n",
+ j, sar_table.values[idx]);
+ }
+ }
+
+ ret = iwl_mvm_send_cmd_pdu(mvm, REDUCE_TX_POWER_CMD, 0,
+ sizeof(cmd), &cmd);
+ if (ret)
+ IWL_ERR(mvm, "failed to set per-chain TX power: %d\n", ret);
+
+ return ret;
+}
+
int iwl_mvm_up(struct iwl_mvm *mvm)
{
int ret, i;
@@ -1124,6 +1293,10 @@
}
#endif
+ ret = iwl_mvm_sar_init(mvm);
+ if (ret)
+ goto error;
+
IWL_DEBUG_INFO(mvm, "RT uCode started.\n");
return 0;
error:
