[+ Oliver]
Hi Joakim,
Am 2020-06-30 04:42, schrieb Joakim Zhang:
-----Original Message-----
From: Michael Walle <michael@xxxxxxxx>
Sent: 2020年6月30日 2:18
To: linux-can@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx;
linux-kernel@xxxxxxxxxxxxxxx
Cc: Wolfgang Grandegger <wg@xxxxxxxxxxxxxx>; Marc Kleine-Budde
<mkl@xxxxxxxxxxxxxx>; David S . Miller <davem@xxxxxxxxxxxxx>; Jakub
Kicinski <kuba@xxxxxxxxxx>; Joakim Zhang <qiangqing.zhang@xxxxxxx>;
dl-linux-imx <linux-imx@xxxxxxx>; Michael Walle <michael@xxxxxxxx>
Subject: [PATCH 2/2] can: flexcan: add support for ISO CAN-FD
Up until now, the controller used non-ISO CAN-FD mode, although it
supports it.
Add support for ISO mode, too. By default the hardware is in non-ISO
mode and
an enable bit has to be explicitly set.
Signed-off-by: Michael Walle <michael@xxxxxxxx>
---
drivers/net/can/flexcan.c | 19 ++++++++++++++++---
1 file changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
index
183e094f8d66..a92d3cdf4195 100644
--- a/drivers/net/can/flexcan.c
+++ b/drivers/net/can/flexcan.c
@@ -94,6 +94,7 @@
#define FLEXCAN_CTRL2_MRP BIT(18)
#define FLEXCAN_CTRL2_RRS BIT(17)
#define FLEXCAN_CTRL2_EACEN BIT(16)
+#define FLEXCAN_CTRL2_ISOCANFDEN BIT(12)
/* FLEXCAN memory error control register (MECR) bits */
#define FLEXCAN_MECR_ECRWRDIS BIT(31)
@@ -1344,14 +1345,25 @@ static int flexcan_chip_start(struct
net_device
*dev)
else
reg_mcr |= FLEXCAN_MCR_SRX_DIS;
- /* MCR - CAN-FD */
- if (priv->can.ctrlmode & CAN_CTRLMODE_FD)
+ /* MCR, CTRL2
+ *
+ * CAN-FD mode
+ * ISO CAN-FD mode
+ */
+ reg_ctrl2 = priv->read(®s->ctrl2);
+ if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
reg_mcr |= FLEXCAN_MCR_FDEN;
- else
+ reg_ctrl2 |= FLEXCAN_CTRL2_ISOCANFDEN;
+ } else {
reg_mcr &= ~FLEXCAN_MCR_FDEN;
+ }
+
+ if (priv->can.ctrlmode & CAN_CTRLMODE_FD_NON_ISO)
+ reg_ctrl2 &= ~FLEXCAN_CTRL2_ISOCANFDEN;
[..]
ip link set can0 up type can bitrate 1000000 dbitrate 5000000 fd on
ip link set can0 up type can bitrate 1000000 dbitrate 5000000 fd on \
fd-non-iso on
vs.
ip link set can0 up type can bitrate 1000000 dbitrate 5000000
fd-non-iso on
I haven't found anything if CAN_CTRLMODE_FD_NON_ISO depends on
CAN_CTRLMODE_FD. I.e. wether CAN_CTRLMODE_FD_NON_ISO can only be set if
CAN_CTRLMODE_FD is also set.
Only the following piece of code, which might be a hint that you
have to set CAN_CTRLMODE_FD if you wan't to use CAN_CTRLMODE_FD_NON_ISO:
drivers/net/can/dev.c:
/* do not check for static fd-non-iso if 'fd' is disabled */
if (!(maskedflags & CAN_CTRLMODE_FD))
ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
If CAN_CTRLMODE_FD_NON_ISO can be set without CAN_CTRLMODE_FD, what
should be the mode if both are set at the same time?
Marc? Oliver?
-michael
