The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x 6d849ff573722afcf5508d2800017bdd40f27eb9 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025120155-wrench-aching-b242@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 6d849ff573722afcf5508d2800017bdd40f27eb9 Mon Sep 17 00:00:00 2001 From: Biju Das biju.das.jz@bp.renesas.com Date: Tue, 18 Nov 2025 12:39:25 +0000 Subject: [PATCH] can: rcar_canfd: Fix CAN-FD mode as default
The commit 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting") has aligned with the flow mentioned in the hardware manual for all SoCs except R-Car Gen3 and RZ/G2L SoCs. On R-Car Gen4 and RZ/G3E SoCs, due to the wrong logic in the commit[1] sets the default mode to FD-Only mode instead of CAN-FD mode.
This patch sets the CAN-FD mode as the default for all SoCs by dropping the rcar_canfd_set_mode() as some SoC requires mode setting in global reset mode, and the rest of the SoCs in channel reset mode and update the rcar_canfd_reset_controller() to take care of these constraints. Moreover, the RZ/G3E and R-Car Gen4 SoCs support 3 modes compared to 2 modes on the R-Car Gen3. Use inverted logic in rcar_canfd_reset_controller() to simplify the code later to support FD-only mode.
[1] commit 45721c406dcf ("can: rcar_canfd: Add support for r8a779a0 SoC")
Fixes: 5cff263606a1 ("can: rcar_canfd: Fix controller mode setting") Cc: stable@vger.kernel.org Signed-off-by: Biju Das biju.das.jz@bp.renesas.com Link: https://patch.msgid.link/20251118123926.193445-1-biju.das.jz@bp.renesas.com Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de
diff --git a/drivers/net/can/rcar/rcar_canfd.c b/drivers/net/can/rcar/rcar_canfd.c index 45d36adb51b7..4c0d7d26df9f 100644 --- a/drivers/net/can/rcar/rcar_canfd.c +++ b/drivers/net/can/rcar/rcar_canfd.c @@ -709,6 +709,11 @@ static void rcar_canfd_set_bit_reg(void __iomem *addr, u32 val) rcar_canfd_update(val, val, addr); }
+static void rcar_canfd_clear_bit_reg(void __iomem *addr, u32 val) +{ + rcar_canfd_update(val, 0, addr); +} + static void rcar_canfd_update_bit_reg(void __iomem *addr, u32 mask, u32 val) { rcar_canfd_update(mask, val, addr); @@ -755,25 +760,6 @@ static void rcar_canfd_set_rnc(struct rcar_canfd_global *gpriv, unsigned int ch, rcar_canfd_set_bit(gpriv->base, RCANFD_GAFLCFG(w), rnc); }
-static void rcar_canfd_set_mode(struct rcar_canfd_global *gpriv) -{ - if (gpriv->info->ch_interface_mode) { - u32 ch, val = gpriv->fdmode ? RCANFD_GEN4_FDCFG_FDOE - : RCANFD_GEN4_FDCFG_CLOE; - - for_each_set_bit(ch, &gpriv->channels_mask, - gpriv->info->max_channels) - rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg, val); - } else { - if (gpriv->fdmode) - rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG, - RCANFD_GRMCFG_RCMC); - else - rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG, - RCANFD_GRMCFG_RCMC); - } -} - static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv) { struct device *dev = &gpriv->pdev->dev; @@ -806,6 +792,16 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv) /* Reset Global error flags */ rcar_canfd_write(gpriv->base, RCANFD_GERFL, 0x0);
+ /* Set the controller into appropriate mode */ + if (!gpriv->info->ch_interface_mode) { + if (gpriv->fdmode) + rcar_canfd_set_bit(gpriv->base, RCANFD_GRMCFG, + RCANFD_GRMCFG_RCMC); + else + rcar_canfd_clear_bit(gpriv->base, RCANFD_GRMCFG, + RCANFD_GRMCFG_RCMC); + } + /* Transition all Channels to reset mode */ for_each_set_bit(ch, &gpriv->channels_mask, gpriv->info->max_channels) { rcar_canfd_clear_bit(gpriv->base, @@ -823,10 +819,23 @@ static int rcar_canfd_reset_controller(struct rcar_canfd_global *gpriv) dev_dbg(dev, "channel %u reset failed\n", ch); return err; } - }
- /* Set the controller into appropriate mode */ - rcar_canfd_set_mode(gpriv); + /* Set the controller into appropriate mode */ + if (gpriv->info->ch_interface_mode) { + /* Do not set CLOE and FDOE simultaneously */ + if (!gpriv->fdmode) { + rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg, + RCANFD_GEN4_FDCFG_FDOE); + rcar_canfd_set_bit_reg(&gpriv->fcbase[ch].cfdcfg, + RCANFD_GEN4_FDCFG_CLOE); + } else { + rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg, + RCANFD_GEN4_FDCFG_FDOE); + rcar_canfd_clear_bit_reg(&gpriv->fcbase[ch].cfdcfg, + RCANFD_GEN4_FDCFG_CLOE); + } + } + }
return 0; }