--- /dev/null
+From d887087c896881715c1a82f1d4f71fbfe5344ffd Mon Sep 17 00:00:00 2001
+From: Biju Das <biju.das.jz@bp.renesas.com>
+Date: Tue, 25 Oct 2022 16:56:56 +0100
+Subject: can: rcar_canfd: fix channel specific IRQ handling for RZ/G2L
+
+From: Biju Das <biju.das.jz@bp.renesas.com>
+
+commit d887087c896881715c1a82f1d4f71fbfe5344ffd upstream.
+
+RZ/G2L has separate channel specific IRQs for transmit and error
+interrupts. But the IRQ handler processes both channels, even if there
+no interrupt occurred on one of the channels.
+
+This patch fixes the issue by passing a channel specific context
+parameter instead of global one for the IRQ register and the IRQ
+handler, it just handles the channel which is triggered the interrupt.
+
+Fixes: 76e9353a80e9 ("can: rcar_canfd: Add support for RZ/G2L family")
+Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
+Link: https://lore.kernel.org/all/20221025155657.1426948-3-biju.das.jz@bp.renesas.com
+Cc: stable@vger.kernel.org
+[mkl: adjust commit message]
+Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
+[biju: fixed the conflicts manually]
+Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/can/rcar/rcar_canfd.c | 18 +++++++-----------
+ 1 file changed, 7 insertions(+), 11 deletions(-)
+
+--- a/drivers/net/can/rcar/rcar_canfd.c
++++ b/drivers/net/can/rcar/rcar_canfd.c
+@@ -1195,11 +1195,9 @@ static void rcar_canfd_handle_channel_tx
+
+ static irqreturn_t rcar_canfd_channel_tx_interrupt(int irq, void *dev_id)
+ {
+- struct rcar_canfd_global *gpriv = dev_id;
+- u32 ch;
++ struct rcar_canfd_channel *priv = dev_id;
+
+- for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS)
+- rcar_canfd_handle_channel_tx(gpriv, ch);
++ rcar_canfd_handle_channel_tx(priv->gpriv, priv->channel);
+
+ return IRQ_HANDLED;
+ }
+@@ -1227,11 +1225,9 @@ static void rcar_canfd_handle_channel_er
+
+ static irqreturn_t rcar_canfd_channel_err_interrupt(int irq, void *dev_id)
+ {
+- struct rcar_canfd_global *gpriv = dev_id;
+- u32 ch;
++ struct rcar_canfd_channel *priv = dev_id;
+
+- for_each_set_bit(ch, &gpriv->channels_mask, RCANFD_NUM_CHANNELS)
+- rcar_canfd_handle_channel_err(gpriv, ch);
++ rcar_canfd_handle_channel_err(priv->gpriv, priv->channel);
+
+ return IRQ_HANDLED;
+ }
+@@ -1649,6 +1645,7 @@ static int rcar_canfd_channel_probe(stru
+ priv->ndev = ndev;
+ priv->base = gpriv->base;
+ priv->channel = ch;
++ priv->gpriv = gpriv;
+ priv->can.clock.freq = fcan_freq;
+ dev_info(&pdev->dev, "can_clk rate is %u\n", priv->can.clock.freq);
+
+@@ -1677,7 +1674,7 @@ static int rcar_canfd_channel_probe(stru
+ }
+ err = devm_request_irq(&pdev->dev, err_irq,
+ rcar_canfd_channel_err_interrupt, 0,
+- irq_name, gpriv);
++ irq_name, priv);
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq CH Err(%d) failed, error %d\n",
+ err_irq, err);
+@@ -1691,7 +1688,7 @@ static int rcar_canfd_channel_probe(stru
+ }
+ err = devm_request_irq(&pdev->dev, tx_irq,
+ rcar_canfd_channel_tx_interrupt, 0,
+- irq_name, gpriv);
++ irq_name, priv);
+ if (err) {
+ dev_err(&pdev->dev, "devm_request_irq Tx (%d) failed, error %d\n",
+ tx_irq, err);
+@@ -1715,7 +1712,6 @@ static int rcar_canfd_channel_probe(stru
+
+ priv->can.do_set_mode = rcar_canfd_do_set_mode;
+ priv->can.do_get_berr_counter = rcar_canfd_get_berr_counter;
+- priv->gpriv = gpriv;
+ SET_NETDEV_DEV(ndev, &pdev->dev);
+
+ netif_napi_add(ndev, &priv->napi, rcar_canfd_rx_poll,
--- /dev/null
+From 702de2c21eed04c67cefaaedc248ef16e5f6b293 Mon Sep 17 00:00:00 2001
+From: Biju Das <biju.das.jz@bp.renesas.com>
+Date: Tue, 25 Oct 2022 16:56:55 +0100
+Subject: can: rcar_canfd: rcar_canfd_handle_global_receive(): fix IRQ storm on global FIFO receive
+
+From: Biju Das <biju.das.jz@bp.renesas.com>
+
+commit 702de2c21eed04c67cefaaedc248ef16e5f6b293 upstream.
+
+We are seeing an IRQ storm on the global receive IRQ line under heavy
+CAN bus load conditions with both CAN channels enabled.
+
+Conditions:
+
+The global receive IRQ line is shared between can0 and can1, either of
+the channels can trigger interrupt while the other channel's IRQ line
+is disabled (RFIE).
+
+When global a receive IRQ interrupt occurs, we mask the interrupt in
+the IRQ handler. Clearing and unmasking of the interrupt is happening
+in rx_poll(). There is a race condition where rx_poll() unmasks the
+interrupt, but the next IRQ handler does not mask the IRQ due to
+NAPIF_STATE_MISSED flag (e.g.: can0 RX FIFO interrupt is disabled and
+can1 is triggering RX interrupt, the delay in rx_poll() processing
+results in setting NAPIF_STATE_MISSED flag) leading to an IRQ storm.
+
+This patch fixes the issue by checking IRQ active and enabled before
+handling the IRQ on a particular channel.
+
+Fixes: dd3bd23eb438 ("can: rcar_canfd: Add Renesas R-Car CAN FD driver")
+Suggested-by: Marc Kleine-Budde <mkl@pengutronix.de>
+Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
+Link: https://lore.kernel.org/all/20221025155657.1426948-2-biju.das.jz@bp.renesas.com
+Cc: stable@vger.kernel.org
+[mkl: adjust commit message]
+Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
+[biju: removed gpriv from RCANFD_RFCC_RFIE macro]
+Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/net/can/rcar/rcar_canfd.c | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/net/can/rcar/rcar_canfd.c
++++ b/drivers/net/can/rcar/rcar_canfd.c
+@@ -1106,11 +1106,13 @@ static void rcar_canfd_handle_global_rec
+ {
+ struct rcar_canfd_channel *priv = gpriv->ch[ch];
+ u32 ridx = ch + RCANFD_RFFIFO_IDX;
+- u32 sts;
++ u32 sts, cc;
+
+ /* Handle Rx interrupts */
+ sts = rcar_canfd_read(priv->base, RCANFD_RFSTS(ridx));
+- if (likely(sts & RCANFD_RFSTS_RFIF)) {
++ cc = rcar_canfd_read(priv->base, RCANFD_RFCC(ridx));
++ if (likely(sts & RCANFD_RFSTS_RFIF &&
++ cc & RCANFD_RFCC_RFIE)) {
+ if (napi_schedule_prep(&priv->napi)) {
+ /* Disable Rx FIFO interrupts */
+ rcar_canfd_clear_bit(priv->base,
projects / thirdparty / kernel / stable-queue.git / commitdiff
