static void ar9003_hw_do_getnf(struct ath_hw *ah,
                              int16_t nfarray[NUM_NF_READINGS])
 {
-       int16_t nf;
-
-       nf = MS(REG_READ(ah, AR_PHY_CCA_0), AR_PHY_MINCCA_PWR);
-       nfarray[0] = sign_extend32(nf, 8);
-
-       nf = MS(REG_READ(ah, AR_PHY_CCA_1), AR_PHY_CH1_MINCCA_PWR);
-       nfarray[1] = sign_extend32(nf, 8);
+#define AR_PHY_CH_MINCCA_PWR   0x1FF00000
+#define AR_PHY_CH_MINCCA_PWR_S 20
+#define AR_PHY_CH_EXT_MINCCA_PWR 0x01FF0000
+#define AR_PHY_CH_EXT_MINCCA_PWR_S 16
 
-       nf = MS(REG_READ(ah, AR_PHY_CCA_2), AR_PHY_CH2_MINCCA_PWR);
-       nfarray[2] = sign_extend32(nf, 8);
-
-       if (!IS_CHAN_HT40(ah->curchan))
-               return;
+       int16_t nf;
+       int i;
 
-       nf = MS(REG_READ(ah, AR_PHY_EXT_CCA), AR_PHY_EXT_MINCCA_PWR);
-       nfarray[3] = sign_extend32(nf, 8);
+       for (i = 0; i < AR9300_MAX_CHAINS; i++) {
+               if (ah->rxchainmask & BIT(i)) {
+                       nf = MS(REG_READ(ah, ah->nf_regs[i]),
+                                        AR_PHY_CH_MINCCA_PWR);
+                       nfarray[i] = sign_extend32(nf, 8);
 
-       nf = MS(REG_READ(ah, AR_PHY_EXT_CCA_1), AR_PHY_CH1_EXT_MINCCA_PWR);
-       nfarray[4] = sign_extend32(nf, 8);
+                       if (IS_CHAN_HT40(ah->curchan)) {
+                               u8 ext_idx = AR9300_MAX_CHAINS + i;
 
-       nf = MS(REG_READ(ah, AR_PHY_EXT_CCA_2), AR_PHY_CH2_EXT_MINCCA_PWR);
-       nfarray[5] = sign_extend32(nf, 8);
+                               nf = MS(REG_READ(ah, ah->nf_regs[ext_idx]),
+                                                AR_PHY_CH_EXT_MINCCA_PWR);
+                               nfarray[ext_idx] = sign_extend32(nf, 8);
+                       }
+               }
+       }
 }
 
 static void ar9003_hw_set_nf_limits(struct ath_hw *ah)