can: kvaser_pciefd: Always disable bus load reporting

BugLink: https://bugs.launchpad.net/bugs/1923220
[ Upstream commit 7c6e6bce08f918b64459415f58061d4d6df44994 ]

Under certain circumstances, when switching from Kvaser's linuxcan driver
(kvpciefd) to the SocketCAN driver (kvaser_pciefd), the bus load reporting
is not disabled.
This is flooding the kernel log with prints like:
[3485.574677] kvaser_pciefd 0000:02:00.0: Received unexpected packet type 0x00000009

Always put the controller in the expected state, instead of assuming that
bus load reporting is inactive.

Note: If bus load reporting is enabled when the driver is loaded, you will
      still get a number of bus load packages (and printouts), before it is
      disabled.

Fixes: 26ad340e582d ("can: kvaser_pciefd: Add driver for Kvaser PCIEcan devices")
Link: https://lore.kernel.org/r/20210309091724.31262-1-jimmyassarsson@gmail.com
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

diff --git a/drivers/net/can/kvaser_pciefd.c b/drivers/net/can/kvaser_pciefd.c
index 72acd1ba162d2671e99d30167d45bb7cb771b371..e7a26ec9bdc11dbd33d24bf432dec048522f8be6 100644 (file)
--- a/drivers/net/can/kvaser_pciefd.c
+++ b/drivers/net/can/kvaser_pciefd.c
@@ -57,6 +57,7 @@ MODULE_DESCRIPTION("CAN driver for Kvaser CAN/PCIe devices");
 #define KVASER_PCIEFD_KCAN_STAT_REG 0x418
 #define KVASER_PCIEFD_KCAN_MODE_REG 0x41c
 #define KVASER_PCIEFD_KCAN_BTRN_REG 0x420
+#define KVASER_PCIEFD_KCAN_BUS_LOAD_REG 0x424
 #define KVASER_PCIEFD_KCAN_BTRD_REG 0x428
 #define KVASER_PCIEFD_KCAN_PWM_REG 0x430
 /* Loopback control register */
@@ -947,6 +948,9 @@ static int kvaser_pciefd_setup_can_ctrls(struct kvaser_pciefd *pcie)
                timer_setup(&can->bec_poll_timer, kvaser_pciefd_bec_poll_timer,
                            0);
 
+               /* Disable Bus load reporting */
+               iowrite32(0, can->reg_base + KVASER_PCIEFD_KCAN_BUS_LOAD_REG);
+
                tx_npackets = ioread32(can->reg_base +
                                       KVASER_PCIEFD_KCAN_TX_NPACKETS_REG);
                if (((tx_npackets >> KVASER_PCIEFD_KCAN_TX_NPACKETS_MAX_SHIFT) &