mwlwifi: fix excessive use of busy-waiting that was tripping up the flash driver

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/package/kernel/mwlwifi/patches/200-fix_excessive_delays.patch b/package/kernel/mwlwifi/patches/200-fix_excessive_delays.patch
new file mode 100644 (file)
index 0000000..43523ed
--- /dev/null
+++ b/package/kernel/mwlwifi/patches/200-fix_excessive_delays.patch
@@ -0,0 +1,73 @@
+--- a/fwcmd.c
++++ b/fwcmd.c
+@@ -132,7 +132,7 @@ static int mwl_fwcmd_wait_complete(struc
+                       int_code = le16_to_cpu(*((__le16 *)&priv->pcmd_buf[2]));
+               else
+                       int_code = le16_to_cpu(*((__le16 *)&priv->pcmd_buf[0]));
+-              mdelay(1);
++              usleep_range(1000, 2000);
+       } while ((int_code != cmd) && (--curr_iteration));
+ 
+       if (curr_iteration == 0) {
+@@ -142,7 +142,7 @@ static int mwl_fwcmd_wait_complete(struc
+               return -EIO;
+       }
+ 
+-      mdelay(3);
++      usleep_range(3000, 5000);
+ 
+       return 0;
+ }
+--- a/fwdl.c
++++ b/fwdl.c
+@@ -74,7 +74,7 @@ int mwl_fwdl_download_firmware(struct ie
+       /* FW before jumping to boot rom, it will enable PCIe transaction retry,
+        * wait for boot code to stop it.
+        */
+-      mdelay(FW_CHECK_MSECS);
++      usleep_range(FW_CHECK_MSECS * 1000, FW_CHECK_MSECS * 2000);
+ 
+       writel(MACREG_A2HRIC_BIT_MASK,
+              priv->iobase1 + MACREG_REG_A2H_INTERRUPT_CLEAR_SEL);
+@@ -95,7 +95,7 @@ int mwl_fwdl_download_firmware(struct ie
+ 
+       /* make sure SCRATCH2 C40 is clear, in case we are too quick */
+       while (readl(priv->iobase1 + 0xc40) == 0)
+-              ;
++              cond_resched();
+ 
+       while (size_fw_downloaded < fw->size) {
+               len = readl(priv->iobase1 + 0xc40);
+@@ -125,6 +125,7 @@ int mwl_fwdl_download_firmware(struct ie
+                       int_code = readl(priv->iobase1 + 0xc1c);
+                       if (int_code != 0)
+                               break;
++                      cond_resched();
+                       curr_iteration--;
+               } while (curr_iteration);
+ 
+@@ -133,6 +134,7 @@ int mwl_fwdl_download_firmware(struct ie
+                       if ((int_code & MACREG_H2ARIC_BIT_DOOR_BELL) !=
+                           MACREG_H2ARIC_BIT_DOOR_BELL)
+                               break;
++                      cond_resched();
+                       curr_iteration--;
+               } while (curr_iteration);
+ 
+@@ -167,12 +169,14 @@ int mwl_fwdl_download_firmware(struct ie
+       do {
+               curr_iteration--;
+               if (priv->mfg_mode && priv->chip_type == MWL8897) {
+-                      mdelay(FW_CHECK_MSECS);
++                      usleep_range(FW_CHECK_MSECS * 1000,
++                                   FW_CHECK_MSECS * 2000);
+                       int_code = readl(priv->iobase1 + 0xc44);
+               } else {
+                       writel(HOSTCMD_SOFTAP_MODE,
+                              priv->iobase1 + MACREG_REG_GEN_PTR);
+-                      mdelay(FW_CHECK_MSECS);
++                      usleep_range(FW_CHECK_MSECS * 1000,
++                                   FW_CHECK_MSECS * 2000);
+                       int_code = readl(priv->iobase1 + MACREG_REG_INT_CODE);
+               }
+               if (!(curr_iteration % 0xff) && (int_code != 0))