ath9k_hw: complete AR9003 calibration

This goes with some new shiny TX IQ calibration that AR9003
hardware family supports.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index 67b3b65..fee07fd 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -814,6 +814,105 @@
 	ah->nf_5g_min = AR_PHY_CCA_MIN_GOOD_VAL_9300_5GHZ;
 }
 
+/*
+ * Find out which of the RX chains are enabled
+ */
+static u32 ar9003_hw_get_rx_chainmask(struct ath_hw *ah)
+{
+	u32 chain = REG_READ(ah, AR_PHY_RX_CHAINMASK);
+	/*
+	 * The bits [2:0] indicate the rx chain mask and are to be
+	 * interpreted as follows:
+	 * 00x => Only chain 0 is enabled
+	 * 01x => Chain 1 and 0 enabled
+	 * 1xx => Chain 2,1 and 0 enabled
+	 */
+	return chain & 0x7;
+}
+
+static void ar9003_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
+{
+	struct ath9k_nfcal_hist *h;
+	unsigned i, j;
+	int32_t val;
+	const u32 ar9300_cca_regs[6] = {
+		AR_PHY_CCA_0,
+		AR_PHY_CCA_1,
+		AR_PHY_CCA_2,
+		AR_PHY_EXT_CCA,
+		AR_PHY_EXT_CCA_1,
+		AR_PHY_EXT_CCA_2,
+	};
+	u8 chainmask, rx_chain_status;
+	struct ath_common *common = ath9k_hw_common(ah);
+
+	rx_chain_status = ar9003_hw_get_rx_chainmask(ah);
+
+	chainmask = 0x3F;
+	h = ah->nfCalHist;
+
+	for (i = 0; i < NUM_NF_READINGS; i++) {
+		if (chainmask & (1 << i)) {
+			val = REG_READ(ah, ar9300_cca_regs[i]);
+			val &= 0xFFFFFE00;
+			val |= (((u32) (h[i].privNF) << 1) & 0x1ff);
+			REG_WRITE(ah, ar9300_cca_regs[i], val);
+		}
+	}
+
+	/*
+	 * Load software filtered NF value into baseband internal minCCApwr
+	 * variable.
+	 */
+	REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL,
+		    AR_PHY_AGC_CONTROL_ENABLE_NF);
+	REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL,
+		    AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
+	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF);
+
+	/*
+	 * Wait for load to complete, should be fast, a few 10s of us.
+	 * The max delay was changed from an original 250us to 10000us
+	 * since 250us often results in NF load timeout and causes deaf
+	 * condition during stress testing 12/12/2009
+	 */
+	for (j = 0; j < 1000; j++) {
+		if ((REG_READ(ah, AR_PHY_AGC_CONTROL) &
+		     AR_PHY_AGC_CONTROL_NF) == 0)
+			break;
+		udelay(10);
+	}
+
+	/*
+	 * We timed out waiting for the noisefloor to load, probably due to an
+	 * in-progress rx. Simply return here and allow the load plenty of time
+	 * to complete before the next calibration interval.  We need to avoid
+	 * trying to load -50 (which happens below) while the previous load is
+	 * still in progress as this can cause rx deafness. Instead by returning
+	 * here, the baseband nf cal will just be capped by our present
+	 * noisefloor until the next calibration timer.
+	 */
+	if (j == 1000) {
+		ath_print(common, ATH_DBG_ANY, "Timeout while waiting for nf "
+			  "to load: AR_PHY_AGC_CONTROL=0x%x\n",
+			  REG_READ(ah, AR_PHY_AGC_CONTROL));
+	}
+
+	/*
+	 * Restore maxCCAPower register parameter again so that we're not capped
+	 * by the median we just loaded.  This will be initial (and max) value
+	 * of next noise floor calibration the baseband does.
+	 */
+	for (i = 0; i < NUM_NF_READINGS; i++) {
+		if (chainmask & (1 << i)) {
+			val = REG_READ(ah, ar9300_cca_regs[i]);
+			val &= 0xFFFFFE00;
+			val |= (((u32) (-50) << 1) & 0x1ff);
+			REG_WRITE(ah, ar9300_cca_regs[i], val);
+		}
+	}
+}
+
 void ar9003_hw_attach_phy_ops(struct ath_hw *ah)
 {
 	struct ath_hw_private_ops *priv_ops = ath9k_hw_private_ops(ah);
@@ -833,4 +932,5 @@
 	priv_ops->set_diversity = ar9003_hw_set_diversity;
 	priv_ops->ani_control = ar9003_hw_ani_control;
 	priv_ops->do_getnf = ar9003_hw_do_getnf;
+	priv_ops->loadnf = ar9003_hw_loadnf;
 }