net: marvell: prestera: disable events interrupt while handling

There are change in firmware which requires that receiver will
disable event interrupts before handling them and enable them
after finish with handling. Events still may come into the queue
but without receiver interruption.
Signed-off-by: Vadym Kochan <vkochan@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/prestera/prestera_pci.c

 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 /* Copyright (c) 2019-2020 Marvell International Ltd. All rights reserved */
 
+#include <linux/bitfield.h>
 #include <linux/circ_buf.h>
 #include <linux/device.h>
 #include <linux/firmware.h>
@@ -144,6 +145,11 @@ struct prestera_fw_regs {
 /* PRESTERA_CMD_RCV_CTL_REG flags */
 #define PRESTERA_CMD_F_REPL_SENT	BIT(0)
 
+#define PRESTERA_FW_EVT_CTL_STATUS_MASK	GENMASK(1, 0)
+
+#define PRESTERA_FW_EVT_CTL_STATUS_ON	0
+#define PRESTERA_FW_EVT_CTL_STATUS_OFF	1
+
 #define PRESTERA_EVTQ_REG_OFFSET(q, f)			\
 	(PRESTERA_FW_REG_OFFSET(evtq_list) +		\
 	 (q) * sizeof(struct prestera_fw_evtq_regs) +	\
@@ -260,6 +266,15 @@ static u8 prestera_fw_evtq_pick(struct prestera_fw *fw)
 	return PRESTERA_EVT_QNUM_MAX;
 }
 
+static void prestera_fw_evt_ctl_status_set(struct prestera_fw *fw, u32 val)
+{
+	u32 status = prestera_fw_read(fw, PRESTERA_FW_STATUS_REG);
+
+	u32p_replace_bits(&status, val, PRESTERA_FW_EVT_CTL_STATUS_MASK);
+
+	prestera_fw_write(fw, PRESTERA_FW_STATUS_REG, status);
+}
+
 static void prestera_fw_evt_work_fn(struct work_struct *work)
 {
 	struct prestera_fw *fw;
@@ -269,6 +284,8 @@ static void prestera_fw_evt_work_fn(struct work_struct *work)
 	fw = container_of(work, struct prestera_fw, evt_work);
 	msg = fw->evt_msg;
 
+	prestera_fw_evt_ctl_status_set(fw, PRESTERA_FW_EVT_CTL_STATUS_OFF);
+
 	while ((qid = prestera_fw_evtq_pick(fw)) < PRESTERA_EVT_QNUM_MAX) {
 		u32 idx;
 		u32 len;
@@ -288,6 +305,8 @@ static void prestera_fw_evt_work_fn(struct work_struct *work)
 		if (fw->dev.recv_msg)
 			fw->dev.recv_msg(&fw->dev, msg, len);
 	}
+
+	prestera_fw_evt_ctl_status_set(fw, PRESTERA_FW_EVT_CTL_STATUS_ON);
 }
 
 static int prestera_fw_wait_reg32(struct prestera_fw *fw, u32 reg, u32 cmp,