[dpdk-dev] [PATCH 07/20] net/i40e/base: improve the polling mechanism

[Qi Zhang]

This patch fixes the polling mechanism of GLGEN_RSTAT.DEVSTATE
in the PF Reset path when Global Reset is in progress.
While the driver is polling for the end of the PF Reset and
the Global Reset is triggered, abandon the PF Reset path and
prepare for the upcoming Global Reset.

Cc: stable at dpdk.org

Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
---
 drivers/net/i40e/base/i40e_common.c | 35 +++++++++++++++++++++++++++++------
 1 file changed, 29 insertions(+), 6 deletions(-)

diff --git a/drivers/net/i40e/base/i40e_common.c b/drivers/net/i40e/base/i40e_common.c
index 18009be3b..0affa98ac 100644
--- a/drivers/net/i40e/base/i40e_common.c
+++ b/drivers/net/i40e/base/i40e_common.c
@@ -1296,6 +1296,29 @@ STATIC enum i40e_media_type i40e_get_media_type(struct i40e_hw *hw)
 	return media;
 }
 
+/**
+ * i40e_poll_globr - Poll for Global Reset completion
+ * @hw: pointer to the hardware structure
+ * @retry_limit: how many times to retry before failure
+ **/
+STATIC enum i40e_status_code i40e_poll_globr(struct i40e_hw *hw,
+					     u32 retry_limit)
+{
+	u32 cnt, reg = 0;
+
+	for (cnt = 0; cnt < retry_limit; cnt++) {
+		reg = rd32(hw, I40E_GLGEN_RSTAT);
+		if (!(reg & I40E_GLGEN_RSTAT_DEVSTATE_MASK))
+			return I40E_SUCCESS;
+		i40e_msec_delay(100);
+	}
+
+	DEBUGOUT("Global reset failed.\n");
+	DEBUGOUT1("I40E_GLGEN_RSTAT = 0x%x\n", reg);
+
+	return I40E_ERR_RESET_FAILED;
+}
+
 #define I40E_PF_RESET_WAIT_COUNT	200
 /**
  * i40e_pf_reset - Reset the PF
@@ -1365,14 +1388,14 @@ enum i40e_status_code i40e_pf_reset(struct i40e_hw *hw)
 			if (!(reg & I40E_PFGEN_CTRL_PFSWR_MASK))
 				break;
 			reg2 = rd32(hw, I40E_GLGEN_RSTAT);
-			if (reg2 & I40E_GLGEN_RSTAT_DEVSTATE_MASK) {
-				DEBUGOUT("Core reset upcoming. Skipping PF reset request.\n");
-				DEBUGOUT1("I40E_GLGEN_RSTAT = 0x%x\n", reg2);
-				return I40E_ERR_NOT_READY;
-			}
+			if (reg2 & I40E_GLGEN_RSTAT_DEVSTATE_MASK)
+				break;
 			i40e_msec_delay(1);
 		}
-		if (reg & I40E_PFGEN_CTRL_PFSWR_MASK) {
+		if (reg2 & I40E_GLGEN_RSTAT_DEVSTATE_MASK) {
+			if (i40e_poll_globr(hw, grst_del) != I40E_SUCCESS)
+				return I40E_ERR_RESET_FAILED;
+		} else if (reg & I40E_PFGEN_CTRL_PFSWR_MASK) {
 			DEBUGOUT("PF reset polling failed to complete.\n");
 			return I40E_ERR_RESET_FAILED;
 		}
-- 
2.13.6