[PATCH 06/10] bus/fsl-mc: Add dprc-reset-container support

From: Diana Craciun
Date: Thu Mar 19 2020 - 11:41:28 EST


From: Bharat Bhushan <Bharat.Bhushan@xxxxxxx>

DPRC reset is required by VFIO-mc in order to stop a device
to further generate DMA transactions.

Signed-off-by: Bharat Bhushan <Bharat.Bhushan@xxxxxxx>
Signed-off-by: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
Signed-off-by: Diana Craciun <diana.craciun@xxxxxxxxxxx>
---
drivers/bus/fsl-mc/dprc.c | 41 +++++++++++++++++++++++++++++
drivers/bus/fsl-mc/fsl-mc-private.h | 5 ++++
include/linux/fsl/mc.h | 5 ++++
3 files changed, 51 insertions(+)

diff --git a/drivers/bus/fsl-mc/dprc.c b/drivers/bus/fsl-mc/dprc.c
index 602f030d84eb..5ae17fd957ba 100644
--- a/drivers/bus/fsl-mc/dprc.c
+++ b/drivers/bus/fsl-mc/dprc.c
@@ -72,6 +72,47 @@ int dprc_close(struct fsl_mc_io *mc_io,
}
EXPORT_SYMBOL_GPL(dprc_close);

+/**
+ * dprc_reset_container - Reset child container.
+ * @mc_io: Pointer to MC portal's I/O object
+ * @cmd_flags: Command flags; one or more of 'MC_CMD_FLAG_'
+ * @token: Token of DPRC object
+ * @child_container_id: ID of the container to reset
+ *
+ * In case a software context crashes or becomes non-responsive, the parent
+ * may wish to reset its resources container before the software context is
+ * restarted.
+ *
+ * This routine informs all objects assigned to the child container that the
+ * container is being reset, so they may perform any cleanup operations that are
+ * needed. All objects handles that were owned by the child container shall be
+ * closed.
+ *
+ * Note that such request may be submitted even if the child software context
+ * has not crashed, but the resulting object cleanup operations will not be
+ * aware of that.
+ *
+ * Return: '0' on Success; Error code otherwise.
+ */
+int dprc_reset_container(struct fsl_mc_io *mc_io,
+ u32 cmd_flags,
+ u16 token,
+ int child_container_id)
+{
+ struct fsl_mc_command cmd = { 0 };
+ struct dprc_cmd_reset_container *cmd_params;
+
+ /* prepare command */
+ cmd.header = mc_encode_cmd_header(DPRC_CMDID_RESET_CONT,
+ cmd_flags, token);
+ cmd_params = (struct dprc_cmd_reset_container *)cmd.params;
+ cmd_params->child_container_id = cpu_to_le32(child_container_id);
+
+ /* send command to mc*/
+ return mc_send_command(mc_io, &cmd);
+}
+EXPORT_SYMBOL_GPL(dprc_reset_container);
+
/**
* dprc_set_irq() - Set IRQ information for the DPRC to trigger an interrupt.
* @mc_io: Pointer to MC portal's I/O object
diff --git a/drivers/bus/fsl-mc/fsl-mc-private.h b/drivers/bus/fsl-mc/fsl-mc-private.h
index 81b9a9b16698..66ccf7fb34af 100644
--- a/drivers/bus/fsl-mc/fsl-mc-private.h
+++ b/drivers/bus/fsl-mc/fsl-mc-private.h
@@ -92,6 +92,7 @@ int dpmcp_reset(struct fsl_mc_io *mc_io,
#define DPRC_CMDID_GET_API_VERSION DPRC_CMD(0xa05)

#define DPRC_CMDID_GET_ATTR DPRC_CMD(0x004)
+#define DPRC_CMDID_RESET_CONT DPRC_CMD(0x005)

#define DPRC_CMDID_SET_IRQ DPRC_CMD(0x010)
#define DPRC_CMDID_SET_IRQ_ENABLE DPRC_CMD(0x012)
@@ -112,6 +113,10 @@ struct dprc_cmd_open {
__le32 container_id;
};

+struct dprc_cmd_reset_container {
+ __le32 child_container_id;
+};
+
struct dprc_cmd_set_irq {
/* cmd word 0 */
__le32 irq_val;
diff --git a/include/linux/fsl/mc.h b/include/linux/fsl/mc.h
index f997f8091408..b9d5e5955adb 100644
--- a/include/linux/fsl/mc.h
+++ b/include/linux/fsl/mc.h
@@ -471,6 +471,11 @@ static inline bool is_fsl_mc_bus_dpseci(const struct fsl_mc_device *mc_dev)
return mc_dev->dev.type == &fsl_mc_bus_dpseci_type;
}

+int dprc_reset_container(struct fsl_mc_io *mc_io,
+ u32 cmd_flags,
+ u16 token,
+ int child_container_id);
+
/*
* Data Path Buffer Pool (DPBP) API
* Contains initialization APIs and runtime control APIs for DPBP
--
2.17.1