[PATCH net-next 3/5] net: ipa: add clock reference for remoteproc SSR

From: Alex Elder
Date: Tue Jul 27 2021 - 17:21:42 EST


The remoteproc SSR callback function for the modem requires hardware
access when handling a modem crash or shutdown. Take and later
release an IPA clock reference in ipa_modem_crashed(), to ensure the
hardware is operational.

Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
---
drivers/net/ipa/ipa_modem.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/net/ipa/ipa_modem.c b/drivers/net/ipa/ipa_modem.c
index c851e2cf12552..a744b81db0d9f 100644
--- a/drivers/net/ipa/ipa_modem.c
+++ b/drivers/net/ipa/ipa_modem.c
@@ -20,6 +20,7 @@
#include "ipa_smp2p.h"
#include "ipa_qmi.h"
#include "ipa_uc.h"
+#include "ipa_clock.h"

#define IPA_NETDEV_NAME "rmnet_ipa%d"
#define IPA_NETDEV_TAILROOM 0 /* for padding by mux layer */
@@ -279,6 +280,8 @@ static void ipa_modem_crashed(struct ipa *ipa)
struct device *dev = &ipa->pdev->dev;
int ret;

+ ipa_clock_get(ipa);
+
ipa_endpoint_modem_pause_all(ipa, true);

ipa_endpoint_modem_hol_block_clear_all(ipa);
@@ -303,6 +306,8 @@ static void ipa_modem_crashed(struct ipa *ipa)
ret = ipa_mem_zero_modem(ipa);
if (ret)
dev_err(dev, "error %d zeroing modem memory regions\n", ret);
+
+ ipa_clock_put(ipa);
}

static int ipa_modem_notify(struct notifier_block *nb, unsigned long action,
--
2.27.0