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* [PATCH 1/8] mwifiex: prevent register accesses after host is sleeping
@ 2016-09-28 12:48 Amitkumar Karwar
  2016-09-28 12:48 ` [PATCH 2/8] mwifiex: report error to PCIe for suspend failure Amitkumar Karwar
                   ` (8 more replies)
  0 siblings, 9 replies; 11+ messages in thread
From: Amitkumar Karwar @ 2016-09-28 12:48 UTC (permalink / raw)
  To: linux-wireless; +Cc: Cathy Luo, Nishant Sarmukadam, Amitkumar Karwar

Following is mwifiex driver-firmware host sleep handshake.
It involves three threads. suspend handler, interrupt handler, interrupt
processing in main work queue.

1) Enter suspend handler
2) Download HS_CFG command
3) Response from firmware for HS_CFG
4) Suspend thread waits until handshake completes(i.e hs_activate becomes
   true)
5) SLEEP from firmware
6) SLEEP confirm downloaded to firmware.
7) SLEEP confirm response from firmware
8) Driver processes SLEEP confirm response and set hs_activate to wake up
suspend thread
9) Exit suspend handler
10) Read sleep cookie in loop and wait until it indicates firmware is
sleep.
11) After processing SLEEP confirm response, we are at the end of interrupt
processing routine. Recheck if there are interrupts received while we were
processing them.

During suspend-resume stress test, it's been observed that we may end up
acessing PCIe hardware(in 10 and 11) when PCIe bus is closed which leads
to a kernel crash.

This patch solves the problem with below changes.
a) action 10 above can be done before 8
b) Skip 11 if hs_activated is true. SLEEP confirm response
is the last interrupt from firmware. No need to recheck for
pending interrupts.
c) Add flush_workqueue() in suspend handler.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
---
 drivers/net/wireless/marvell/mwifiex/pcie.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/pcie.c b/drivers/net/wireless/marvell/mwifiex/pcie.c
index 3c3c4f1..2833d47 100644
--- a/drivers/net/wireless/marvell/mwifiex/pcie.c
+++ b/drivers/net/wireless/marvell/mwifiex/pcie.c
@@ -118,6 +118,7 @@ static int mwifiex_pcie_suspend(struct device *dev)
 	adapter = card->adapter;
 
 	hs_actived = mwifiex_enable_hs(adapter);
+	flush_workqueue(adapter->workqueue);
 
 	/* Indicate device suspended */
 	adapter->is_suspended = true;
@@ -1669,9 +1670,6 @@ static int mwifiex_pcie_process_cmd_complete(struct mwifiex_adapter *adapter)
 
 	if (!adapter->curr_cmd) {
 		if (adapter->ps_state == PS_STATE_SLEEP_CFM) {
-			mwifiex_process_sleep_confirm_resp(adapter, skb->data,
-							   skb->len);
-			mwifiex_pcie_enable_host_int(adapter);
 			if (mwifiex_write_reg(adapter,
 					      PCIE_CPU_INT_EVENT,
 					      CPU_INTR_SLEEP_CFM_DONE)) {
@@ -1684,6 +1682,9 @@ static int mwifiex_pcie_process_cmd_complete(struct mwifiex_adapter *adapter)
 			while (reg->sleep_cookie && (count++ < 10) &&
 			       mwifiex_pcie_ok_to_access_hw(adapter))
 				usleep_range(50, 60);
+			mwifiex_pcie_enable_host_int(adapter);
+			mwifiex_process_sleep_confirm_resp(adapter, skb->data,
+							   skb->len);
 		} else {
 			mwifiex_dbg(adapter, ERROR,
 				    "There is no command but got cmdrsp\n");
@@ -2322,6 +2323,8 @@ static int mwifiex_process_pcie_int(struct mwifiex_adapter *adapter)
 			ret = mwifiex_pcie_process_cmd_complete(adapter);
 			if (ret)
 				return ret;
+			if (adapter->hs_activated)
+				return ret;
 		}
 
 		if (card->msi_enable) {
-- 
1.9.1

^ permalink raw reply related	[flat|nested] 11+ messages in thread
end of thread, other threads:[~2016-11-09  1:34 UTC | newest]

Thread overview: 11+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-09-28 12:48 [PATCH 1/8] mwifiex: prevent register accesses after host is sleeping Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 2/8] mwifiex: report error to PCIe for suspend failure Amitkumar Karwar
2016-10-04 22:24   ` [2/8] " Brian Norris
2016-09-28 12:48 ` [PATCH 3/8] mwifiex: Fix NULL pointer dereference in skb_dequeue() Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 4/8] mwifiex: vendor_ie length check for parse WMM IEs Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 5/8] mwifiex: add memrw command information in README Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 6/8] mwifiex: update tx_pkts_queued for requeued packets Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 7/8] mwifiex: fix command timeout problem seen in stress tests Amitkumar Karwar
2016-09-28 12:48 ` [PATCH 8/8] mwifiex: fix p2p device doesn't find in scan problem Amitkumar Karwar
2016-10-04 22:20 ` [PATCH 1/8] mwifiex: prevent register accesses after host is sleeping Brian Norris
2016-11-09  1:34 ` [1/8] " Kalle Valo

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