[PATCH 5.10 103/142] iwlwifi: pcie: set LTR on more devices

Greg Kroah-Hartman
2021-02-02T19:47:45Z

From: Johannes Berg <johannes.berg@intel.com>

[ Upstream commit ed0022da8bd9a3ba1c0e1497457be28d52afa7e1 ]

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: edb625208d84 ("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
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/intel/iwlwifi/iwl-prph.h | 6 +++
.../intel/iwlwifi/pcie/ctxt-info-gen3.c | 39 +++++++++++--------
2 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-prph.h b/drivers/net/wireless/intel/iwlwifi/iwl-prph.h
index fa3f15778fc7b..579578534f9d9 100644
--- a/drivers/net/wireless/intel/iwlwifi/iwl-prph.h
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-prph.h
@@ -355,6 +355,12 @@
#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)
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
index eeb87cf5ee857..d719e433a59bf 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/ctxt-info-gen3.c
@@ -122,6 +122,15 @@ 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;
@@ -253,23 +262,19 @@ 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)
--
2.27.0