From 8101a7f0656bf11c385d6e14f52313b19f017e70 Mon Sep 17 00:00:00 2001 From: Emmanuel Grumbach Date: Thu, 28 Feb 2013 11:54:28 +0200 Subject: iwlwifi: mvm: update the rssi calculation Make the rssi more accurate by taking in count per-chain AGC values. Without this, the RSSI reports inaccurate values. Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- drivers/net/wireless/iwlwifi/mvm/fw-api.h | 18 ++++++++------- drivers/net/wireless/iwlwifi/mvm/mvm.h | 3 ++- drivers/net/wireless/iwlwifi/mvm/rx.c | 37 +++++++++++++++++++------------ 3 files changed, 35 insertions(+), 23 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/mvm/fw-api.h b/drivers/net/wireless/iwlwifi/mvm/fw-api.h index 23eebda848b0..2adb61f103f4 100644 --- a/drivers/net/wireless/iwlwifi/mvm/fw-api.h +++ b/drivers/net/wireless/iwlwifi/mvm/fw-api.h @@ -762,18 +762,20 @@ struct iwl_phy_context_cmd { #define IWL_RX_INFO_PHY_CNT 8 #define IWL_RX_INFO_AGC_IDX 1 #define IWL_RX_INFO_RSSI_AB_IDX 2 -#define IWL_RX_INFO_RSSI_C_IDX 3 -#define IWL_OFDM_AGC_DB_MSK 0xfe00 -#define IWL_OFDM_AGC_DB_POS 9 +#define IWL_OFDM_AGC_A_MSK 0x0000007f +#define IWL_OFDM_AGC_A_POS 0 +#define IWL_OFDM_AGC_B_MSK 0x00003f80 +#define IWL_OFDM_AGC_B_POS 7 +#define IWL_OFDM_AGC_CODE_MSK 0x3fe00000 +#define IWL_OFDM_AGC_CODE_POS 20 #define IWL_OFDM_RSSI_INBAND_A_MSK 0x00ff -#define IWL_OFDM_RSSI_ALLBAND_A_MSK 0xff00 #define IWL_OFDM_RSSI_A_POS 0 +#define IWL_OFDM_RSSI_ALLBAND_A_MSK 0xff00 +#define IWL_OFDM_RSSI_ALLBAND_A_POS 8 #define IWL_OFDM_RSSI_INBAND_B_MSK 0xff0000 -#define IWL_OFDM_RSSI_ALLBAND_B_MSK 0xff000000 #define IWL_OFDM_RSSI_B_POS 16 -#define IWL_OFDM_RSSI_INBAND_C_MSK 0x00ff -#define IWL_OFDM_RSSI_ALLBAND_C_MSK 0xff00 -#define IWL_OFDM_RSSI_C_POS 0 +#define IWL_OFDM_RSSI_ALLBAND_B_MSK 0xff000000 +#define IWL_OFDM_RSSI_ALLBAND_B_POS 24 /** * struct iwl_rx_phy_info - phy info diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h index 537711b10478..bdae700c769e 100644 --- a/drivers/net/wireless/iwlwifi/mvm/mvm.h +++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h @@ -80,7 +80,8 @@ #define IWL_INVALID_MAC80211_QUEUE 0xff #define IWL_MVM_MAX_ADDRESSES 2 -#define IWL_RSSI_OFFSET 44 +/* RSSI offset for WkP */ +#define IWL_RSSI_OFFSET 50 enum iwl_mvm_tx_fifo { IWL_MVM_TX_FIFO_BK = 0, diff --git a/drivers/net/wireless/iwlwifi/mvm/rx.c b/drivers/net/wireless/iwlwifi/mvm/rx.c index 3f40ab05bbd8..b0b190d0ec23 100644 --- a/drivers/net/wireless/iwlwifi/mvm/rx.c +++ b/drivers/net/wireless/iwlwifi/mvm/rx.c @@ -131,33 +131,42 @@ static void iwl_mvm_pass_packet_to_mac80211(struct iwl_mvm *mvm, static int iwl_mvm_calc_rssi(struct iwl_mvm *mvm, struct iwl_rx_phy_info *phy_info) { - u32 rssi_a, rssi_b, rssi_c, max_rssi, agc_db; + int rssi_a, rssi_b, rssi_a_dbm, rssi_b_dbm, max_rssi_dbm; + int rssi_all_band_a, rssi_all_band_b; + u32 agc_a, agc_b, max_agc; u32 val; - /* Find max rssi among 3 possible receivers. + /* Find max rssi among 2 possible receivers. * These values are measured by the Digital Signal Processor (DSP). * They should stay fairly constant even as the signal strength varies, * if the radio's Automatic Gain Control (AGC) is working right. * AGC value (see below) will provide the "interesting" info. */ + val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]); + agc_a = (val & IWL_OFDM_AGC_A_MSK) >> IWL_OFDM_AGC_A_POS; + agc_b = (val & IWL_OFDM_AGC_B_MSK) >> IWL_OFDM_AGC_B_POS; + max_agc = max_t(u32, agc_a, agc_b); + val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_AB_IDX]); rssi_a = (val & IWL_OFDM_RSSI_INBAND_A_MSK) >> IWL_OFDM_RSSI_A_POS; rssi_b = (val & IWL_OFDM_RSSI_INBAND_B_MSK) >> IWL_OFDM_RSSI_B_POS; - val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_C_IDX]); - rssi_c = (val & IWL_OFDM_RSSI_INBAND_C_MSK) >> IWL_OFDM_RSSI_C_POS; - - val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]); - agc_db = (val & IWL_OFDM_AGC_DB_MSK) >> IWL_OFDM_AGC_DB_POS; + rssi_all_band_a = (val & IWL_OFDM_RSSI_ALLBAND_A_MSK) >> + IWL_OFDM_RSSI_ALLBAND_A_POS; + rssi_all_band_b = (val & IWL_OFDM_RSSI_ALLBAND_B_MSK) >> + IWL_OFDM_RSSI_ALLBAND_B_POS; - max_rssi = max_t(u32, rssi_a, rssi_b); - max_rssi = max_t(u32, max_rssi, rssi_c); + /* + * dBm = rssi dB - agc dB - constant. + * Higher AGC (higher radio gain) means lower signal. + */ + rssi_a_dbm = rssi_a - IWL_RSSI_OFFSET - agc_a; + rssi_b_dbm = rssi_b - IWL_RSSI_OFFSET - agc_b; + max_rssi_dbm = max_t(int, rssi_a_dbm, rssi_b_dbm); - IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d C %d Max %d AGC dB %d\n", - rssi_a, rssi_b, rssi_c, max_rssi, agc_db); + IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d Max %d AGCA %d AGCB %d\n", + rssi_a_dbm, rssi_b_dbm, max_rssi_dbm, agc_a, agc_b); - /* dBm = max_rssi dB - agc dB - constant. - * Higher AGC (higher radio gain) means lower signal. */ - return max_rssi - agc_db - IWL_RSSI_OFFSET; + return max_rssi_dbm; } /* -- cgit v1.2.3-55-g7522