iwlwifi: pcie: set LTR on more devices

To avoid completion timeouts during device boot, set up the
LTR timeouts on more devices - similar to what we had before
for AX210.

This also corrects the AX210 workaround to be done only on
discrete (non-integrated) devices, otherwise the registers
have no effect.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fixes: edb625208d ("iwlwifi: pcie: set LTR to avoid completion timeout")
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/iwlwifi.20210115130252.fb819e19530b.I0396f82922db66426f52fbb70d32a29c8fd66951@changeid

drivers/net/wireless/intel/iwlwifi/iwl-prph.h

@@ -301,6 +301,12 @@
 #define RADIO_RSP_ADDR_POS		(6)
 #define RADIO_RSP_RD_CMD		(3)
 
+/* LTR control (Qu only) */
+#define HPM_MAC_LTR_CSR			0xa0348c
+#define HPM_MAC_LRT_ENABLE_ALL		0xf
+/* also uses CSR_LTR_* for values */
+#define HPM_UMAC_LTR			0xa03480
+
 /* FW monitor */
 #define MON_BUFF_SAMPLE_CTL		(0xa03c00)
 #define MON_BUFF_BASE_ADDR		(0xa03c1c)

drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c

@@ -75,6 +75,15 @@ int iwl_pcie_ctxt_info_gen3_init(struct iwl_trans *trans,
 				 const struct fw_img *fw)
 {
 	struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
+	u32 ltr_val = CSR_LTR_LONG_VAL_AD_NO_SNOOP_REQ |
+		      u32_encode_bits(CSR_LTR_LONG_VAL_AD_SCALE_USEC,
+				      CSR_LTR_LONG_VAL_AD_NO_SNOOP_SCALE) |
+		      u32_encode_bits(250,
+				      CSR_LTR_LONG_VAL_AD_NO_SNOOP_VAL) |
+		      CSR_LTR_LONG_VAL_AD_SNOOP_REQ |
+		      u32_encode_bits(CSR_LTR_LONG_VAL_AD_SCALE_USEC,
+				      CSR_LTR_LONG_VAL_AD_SNOOP_SCALE) |
+		      u32_encode_bits(250, CSR_LTR_LONG_VAL_AD_SNOOP_VAL);
 	struct iwl_context_info_gen3 *ctxt_info_gen3;
 	struct iwl_prph_scratch *prph_scratch;
 	struct iwl_prph_scratch_ctrl_cfg *prph_sc_ctrl;
@@ -206,23 +215,19 @@ int iwl_pcie_ctxt_info_gen3_init(struct iwl_trans *trans,
 	iwl_set_bit(trans, CSR_CTXT_INFO_BOOT_CTRL,
 		    CSR_AUTO_FUNC_BOOT_ENA);
 
-	if (trans->trans_cfg->device_family == IWL_DEVICE_FAMILY_AX210) {
-		/*
-		 * The firmware initializes this again later (to a smaller
-		 * value), but for the boot process initialize the LTR to
-		 * ~250 usec.
-		 */
-		u32 val = CSR_LTR_LONG_VAL_AD_NO_SNOOP_REQ |
-			  u32_encode_bits(CSR_LTR_LONG_VAL_AD_SCALE_USEC,
-					  CSR_LTR_LONG_VAL_AD_NO_SNOOP_SCALE) |
-			  u32_encode_bits(250,
-					  CSR_LTR_LONG_VAL_AD_NO_SNOOP_VAL) |
-			  CSR_LTR_LONG_VAL_AD_SNOOP_REQ |
-			  u32_encode_bits(CSR_LTR_LONG_VAL_AD_SCALE_USEC,
-					  CSR_LTR_LONG_VAL_AD_SNOOP_SCALE) |
-			  u32_encode_bits(250, CSR_LTR_LONG_VAL_AD_SNOOP_VAL);
-
-		iwl_write32(trans, CSR_LTR_LONG_VAL_AD, val);
+	/*
+	 * To workaround hardware latency issues during the boot process,
+	 * initialize the LTR to ~250 usec (see ltr_val above).
+	 * The firmware initializes this again later (to a smaller value).
+	 */
+	if ((trans->trans_cfg->device_family == IWL_DEVICE_FAMILY_AX210 ||
+	     trans->trans_cfg->device_family == IWL_DEVICE_FAMILY_22000) &&
+	    !trans->trans_cfg->integrated) {
+		iwl_write32(trans, CSR_LTR_LONG_VAL_AD, ltr_val);
+	} else if (trans->trans_cfg->integrated &&
+		   trans->trans_cfg->device_family == IWL_DEVICE_FAMILY_22000) {
+		iwl_write_prph(trans, HPM_MAC_LTR_CSR, HPM_MAC_LRT_ENABLE_ALL);
+		iwl_write_prph(trans, HPM_UMAC_LTR, ltr_val);
 	}
 
 	if (trans->trans_cfg->device_family >= IWL_DEVICE_FAMILY_AX210)