ath10k: split reset logic from power up

The power up procedure was overly complex due to
warm/cold reset workarounds and issues.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c
index af36730..117e14d 100644 (file)
--- a/drivers/net/wireless/ath/ath10k/pci.c
+++ b/drivers/net/wireless/ath/ath10k/pci.c
@@ -1792,10 +1792,86 @@ static int ath10k_pci_warm_reset(struct ath10k *ar)
        return 0;
 }
 
-static int __ath10k_pci_hif_power_up(struct ath10k *ar, bool cold_reset)
+static int ath10k_pci_chip_reset(struct ath10k *ar)
+{
+       int i, ret;
+       u32 val;
+
+       ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot chip reset\n");
+
+       /* Some hardware revisions (e.g. CUS223v2) has issues with cold reset.
+        * It is thus preferred to use warm reset which is safer but may not be
+        * able to recover the device from all possible fail scenarios.
+        *
+        * Warm reset doesn't always work on first try so attempt it a few
+        * times before giving up.
+        */
+       for (i = 0; i < ATH10K_PCI_NUM_WARM_RESET_ATTEMPTS; i++) {
+               ret = ath10k_pci_warm_reset(ar);
+               if (ret) {
+                       ath10k_warn(ar, "failed to warm reset attempt %d of %d: %d\n",
+                                   i + 1, ATH10K_PCI_NUM_WARM_RESET_ATTEMPTS,
+                                   ret);
+                       continue;
+               }
+
+               /* FIXME: Sometimes copy engine doesn't recover after warm
+                * reset. In most cases this needs cold reset. In some of these
+                * cases the device is in such a state that a cold reset may
+                * lock up the host.
+                *
+                * Reading any host interest register via copy engine is
+                * sufficient to verify if device is capable of booting
+                * firmware blob.
+                */
+               ret = ath10k_pci_init_pipes(ar);
+               if (ret) {
+                       ath10k_warn(ar, "failed to init copy engine: %d\n",
+                                   ret);
+                       continue;
+               }
+
+               ret = ath10k_pci_diag_read32(ar, QCA988X_HOST_INTEREST_ADDRESS,
+                                            &val);
+               if (ret) {
+                       ath10k_warn(ar, "failed to poke copy engine: %d\n",
+                                   ret);
+                       continue;
+               }
+
+               ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot chip reset complete (warm)\n");
+               return 0;
+       }
+
+       if (ath10k_pci_reset_mode == ATH10K_PCI_RESET_WARM_ONLY) {
+               ath10k_warn(ar, "refusing cold reset as requested\n");
+               return -EPERM;
+       }
+
+       ret = ath10k_pci_cold_reset(ar);
+       if (ret) {
+               ath10k_warn(ar, "failed to cold reset: %d\n", ret);
+               return ret;
+       }
+
+       ret = ath10k_pci_wait_for_target_init(ar);
+       if (ret) {
+               ath10k_warn(ar, "failed to wait for target after cold reset: %d\n",
+                           ret);
+               return ret;
+       }
+
+       ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot chip reset complete (cold)\n");
+
+       return 0;
+}
+
+static int ath10k_pci_hif_power_up(struct ath10k *ar)
 {
        int ret;
 
+       ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot hif power up\n");
+
        /*
         * Bring the target up cleanly.
         *
@@ -1806,13 +1882,9 @@ static int __ath10k_pci_hif_power_up(struct ath10k *ar, bool cold_reset)
         * is in an unexpected state. We try to catch that here in order to
         * reset the Target and retry the probe.
         */
-       if (cold_reset)
-               ret = ath10k_pci_cold_reset(ar);
-       else
-               ret = ath10k_pci_warm_reset(ar);
-
+       ret = ath10k_pci_chip_reset(ar);
        if (ret) {
-               ath10k_err(ar, "failed to reset target: %d\n", ret);
+               ath10k_err(ar, "failed to reset chip: %d\n", ret);
                goto err;
        }
 
@@ -1822,12 +1894,6 @@ static int __ath10k_pci_hif_power_up(struct ath10k *ar, bool cold_reset)
                goto err;
        }
 
-       ret = ath10k_pci_wait_for_target_init(ar);
-       if (ret) {
-               ath10k_err(ar, "failed to wait for target to init: %d\n", ret);
-               goto err_ce;
-       }
-
        ret = ath10k_pci_init_config(ar);
        if (ret) {
                ath10k_err(ar, "failed to setup init config: %d\n", ret);
@@ -1844,68 +1910,11 @@ static int __ath10k_pci_hif_power_up(struct ath10k *ar, bool cold_reset)
 
 err_ce:
        ath10k_pci_ce_deinit(ar);
-       ath10k_pci_warm_reset(ar);
-err:
-       return ret;
-}
-
-static int ath10k_pci_hif_power_up_warm(struct ath10k *ar)
-{
-       int i, ret;
-
-       /*
-        * Sometime warm reset succeeds after retries.
-        *
-        * FIXME: It might be possible to tune ath10k_pci_warm_reset() to work
-        * at first try.
-        */
-       for (i = 0; i < ATH10K_PCI_NUM_WARM_RESET_ATTEMPTS; i++) {
-               ret = __ath10k_pci_hif_power_up(ar, false);
-               if (ret == 0)
-                       break;
-
-               ath10k_warn(ar, "failed to warm reset (attempt %d out of %d): %d\n",
-                           i + 1, ATH10K_PCI_NUM_WARM_RESET_ATTEMPTS, ret);
-       }
 
+err:
        return ret;
 }
 
-static int ath10k_pci_hif_power_up(struct ath10k *ar)
-{
-       int ret;
-
-       ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot hif power up\n");
-
-       /*
-        * Hardware CUS232 version 2 has some issues with cold reset and the
-        * preferred (and safer) way to perform a device reset is through a
-        * warm reset.
-        *
-        * Warm reset doesn't always work though so fall back to cold reset may
-        * be necessary.
-        */
-       ret = ath10k_pci_hif_power_up_warm(ar);
-       if (ret) {
-               ath10k_warn(ar, "failed to power up target using warm reset: %d\n",
-                           ret);
-
-               if (ath10k_pci_reset_mode == ATH10K_PCI_RESET_WARM_ONLY)
-                       return ret;
-
-               ath10k_warn(ar, "trying cold reset\n");
-
-               ret = __ath10k_pci_hif_power_up(ar, true);
-               if (ret) {
-                       ath10k_err(ar, "failed to power up target using cold reset too (%d)\n",
-                                  ret);
-                       return ret;
-               }
-       }
-
-       return 0;
-}
-
 static void ath10k_pci_hif_power_down(struct ath10k *ar)
 {
        ath10k_dbg(ar, ATH10K_DBG_BOOT, "boot hif power down\n");