This is a note to let you know that I've just added the patch titled mailbox: arm_mhuv2: Fix a bug for mhuv2_sender_interrupt to the 6.1-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mailbox-arm_mhuv2-fix-a-bug-for-mhuv2_sender_interru.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3a87b5e567495a2d0b86a3a5d905ad7e57753298 Author: Xiaowu.ding <xiaowu.ding@xxxxxxxxxxxxxxx> Date: Tue Dec 12 19:37:22 2023 +0800 mailbox: arm_mhuv2: Fix a bug for mhuv2_sender_interrupt [ Upstream commit ee01c0b4384d19ecc5dfa7db3fd4303f965c3eba ] Message Handling Unit version is v2.1. When arm_mhuv2 working with the data protocol transfer mode. We have split one mhu into two channels, and every channel include four channel windows, the two channels share one gic spi interrupt. There is a problem with the sending scenario. The first channel will take up 0-3 channel windows, and the second channel take up 4-7 channel windows. When the first channel send the data, and the receiver will clear all the four channels status. Although we only enabled the interrupt on the last channel window with register CH_INT_EN,the register CHCOMB_INT_ST0 will be 0xf, not be 0x8. Currently we just clear the last channel windows int status with the data proctol mode.So after that,the CHCOMB_INT_ST0 status will be 0x7, not be the 0x0. Then the second channel send the data, the receiver read the data, clear all the four channel windows status, trigger the sender interrupt. But currently the CHCOMB_INT_ST0 register will be 0xf7, get_irq_chan_comb function will always return the first channel. So this patch clear all channel windows int status to avoid this interrupt confusion. Signed-off-by: Xiaowu.ding <xiaowu.ding@xxxxxxxxxxxxxxx> Acked-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx> Signed-off-by: Jassi Brar <jaswinder.singh@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/mailbox/arm_mhuv2.c b/drivers/mailbox/arm_mhuv2.c index c6d4957c4da8..0ec21dcdbde7 100644 --- a/drivers/mailbox/arm_mhuv2.c +++ b/drivers/mailbox/arm_mhuv2.c @@ -553,7 +553,8 @@ static irqreturn_t mhuv2_sender_interrupt(int irq, void *data) priv = chan->con_priv; if (!IS_PROTOCOL_DOORBELL(priv)) { - writel_relaxed(1, &mhu->send->ch_wn[priv->ch_wn_idx + priv->windows - 1].int_clr); + for (i = 0; i < priv->windows; i++) + writel_relaxed(1, &mhu->send->ch_wn[priv->ch_wn_idx + i].int_clr); if (chan->cl) { mbox_chan_txdone(chan, 0);