Re: [PATCH v3 0/6] can: flexcan: Add NXP S32N79 SoC support

From: Ciprian Marian Costea

Date: Wed Mar 25 2026 - 08:53:26 EST


On 3/24/2026 3:46 PM, Marc Kleine-Budde wrote:
On 23.03.2026 14:58:21, Ciprian Costea wrote:
From: Ciprian Marian Costea <ciprianmarian.costea@xxxxxxxxxxx>

This patch series adds FlexCAN support for the NXP S32N79 SoC.

The S32N79 is an automotive-grade processor from NXP with multiple
FlexCAN instances. The FlexCAN IP integration on S32N79 differs from
other SoCs in the interrupt routing - it uses two separate interrupt
lines:
- one interrupt for mailboxes 0-127
- one interrupt for bus error detection and device state changes

Can you check if the S32N79 suffers from the

| /* No interrupt for error passive */
| #define FLEXCAN_QUIRK_BROKEN_PERR_STATE BIT(6)

problem? Maybe everyone just added the FLEXCAN_QUIRK_BROKEN_PERR_STATE
for the new SoC without actually testing it.

regards,
Marc


Hello Marc,

I've tested on S32N79 hardware. Without the quirk, the controller
reaches Transmit-Error-Counter=128 (error-passive at HW level) but the
driver only sees ERROR-WARNING - the passive interrupt never fires.

With the quirk enabled, ERROR-PASSIVE is correctly reported.
So FLEXCAN_QUIRK_BROKEN_PERR_STATE quirk is needed for S32N79.

Best Regards,
Ciprian