This is a note to let you know that I've just added the patch titled
can: kvaser_pciefd: Empty SRB buffer in probe
to the 5.4-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:
can-kvaser_pciefd-empty-srb-buffer-in-probe.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From c589557dd1426f5adf90c7a919d4fde5a3e4ef64 Mon Sep 17 00:00:00 2001
From: Jimmy Assarsson <extja@xxxxxxxxxx>
Date: Tue, 16 May 2023 15:43:16 +0200
Subject: can: kvaser_pciefd: Empty SRB buffer in probe
From: Jimmy Assarsson <extja@xxxxxxxxxx>
commit c589557dd1426f5adf90c7a919d4fde5a3e4ef64 upstream.
Empty the "Shared receive buffer" (SRB) in probe, to assure we start in a
known state, and don't process any irrelevant packets.
Fixes: 26ad340e582d ("can: kvaser_pciefd: Add driver for Kvaser PCIEcan devices")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jimmy Assarsson <extja@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230516134318.104279-5-extja@xxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/kvaser_pciefd.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)
--- a/drivers/net/can/kvaser_pciefd.c
+++ b/drivers/net/can/kvaser_pciefd.c
@@ -70,10 +70,12 @@ MODULE_DESCRIPTION("CAN driver for Kvase
#define KVASER_PCIEFD_SYSID_BUILD_REG (KVASER_PCIEFD_SYSID_BASE + 0x14)
/* Shared receive buffer registers */
#define KVASER_PCIEFD_SRB_BASE 0x1f200
+#define KVASER_PCIEFD_SRB_FIFO_LAST_REG (KVASER_PCIEFD_SRB_BASE + 0x1f4)
#define KVASER_PCIEFD_SRB_CMD_REG (KVASER_PCIEFD_SRB_BASE + 0x200)
#define KVASER_PCIEFD_SRB_IEN_REG (KVASER_PCIEFD_SRB_BASE + 0x204)
#define KVASER_PCIEFD_SRB_IRQ_REG (KVASER_PCIEFD_SRB_BASE + 0x20c)
#define KVASER_PCIEFD_SRB_STAT_REG (KVASER_PCIEFD_SRB_BASE + 0x210)
+#define KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG (KVASER_PCIEFD_SRB_BASE + 0x214)
#define KVASER_PCIEFD_SRB_CTRL_REG (KVASER_PCIEFD_SRB_BASE + 0x218)
/* EPCS flash controller registers */
#define KVASER_PCIEFD_SPI_BASE 0x1fc00
@@ -110,6 +112,9 @@ MODULE_DESCRIPTION("CAN driver for Kvase
/* DMA support */
#define KVASER_PCIEFD_SRB_STAT_DMA BIT(24)
+/* SRB current packet level */
+#define KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK 0xff
+
/* DMA Enable */
#define KVASER_PCIEFD_SRB_CTRL_DMA_ENABLE BIT(0)
@@ -1053,6 +1058,7 @@ static int kvaser_pciefd_setup_dma(struc
{
int i;
u32 srb_status;
+ u32 srb_packet_count;
dma_addr_t dma_addr[KVASER_PCIEFD_DMA_COUNT];
/* Disable the DMA */
@@ -1080,6 +1086,15 @@ static int kvaser_pciefd_setup_dma(struc
KVASER_PCIEFD_SRB_CMD_RDB1,
pcie->reg_base + KVASER_PCIEFD_SRB_CMD_REG);
+ /* Empty Rx FIFO */
+ srb_packet_count = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_RX_NR_PACKETS_REG) &
+ KVASER_PCIEFD_SRB_RX_NR_PACKETS_MASK;
+ while (srb_packet_count) {
+ /* Drop current packet in FIFO */
+ ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_FIFO_LAST_REG);
+ srb_packet_count--;
+ }
+
srb_status = ioread32(pcie->reg_base + KVASER_PCIEFD_SRB_STAT_REG);
if (!(srb_status & KVASER_PCIEFD_SRB_STAT_DI)) {
dev_err(&pcie->pci->dev, "DMA not idle before enabling\n");
Patches currently in stable-queue which might be from extja@xxxxxxxxxx are
queue-5.4/can-kvaser_pciefd-call-request_irq-before-enabling-interrupts.patch
queue-5.4/can-kvaser_pciefd-set-can_state_stopped-in-kvaser_pciefd_stop.patch
queue-5.4/can-kvaser_pciefd-clear-listen-only-bit-if-not-explicitly-requested.patch
queue-5.4/can-kvaser_pciefd-empty-srb-buffer-in-probe.patch
queue-5.4/can-kvaser_pciefd-disable-interrupts-in-probe-error-path.patch
queue-5.4/can-kvaser_pciefd-do-not-send-eflush-command-on-tfd-interrupt.patch
