From fddb9bcd706ed3bb262f4f37707616dd06c7a4cc Mon Sep 17 00:00:00 2001 From: Igor Skalkin Date: Thu, 5 Nov 2020 22:21:11 +0100 Subject: [PATCH] firmware: arm_scmi: Add xfer_init_buffers transport op The virtio transport in this patch series can be simplified by using the scmi_xfer tx/rx buffers for data exchange with the virtio device, and for saving the message state. But the virtio transport requires prepending a transport-specific header. Also, for data exchange using virtqueues, the tx and rx buffers should not overlap. After the previous patch, this is the second and final step to enable the virtio transport to use the scmi_xfer buffers for data exchange. Add an optional op through which the transport can allocate the tx/rx buffers along with room for the prepended transport-specific headers. Co-developed-by: Peter Hilber Signed-off-by: Peter Hilber Signed-off-by: Igor Skalkin Signed-off-by: Vasyl Vavrychuk --- drivers/firmware/arm_scmi/common.h | 3 +++ drivers/firmware/arm_scmi/driver.c | 21 +++++++++++++++------ 2 files changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index c998ec29018e..ae5db602e45d 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -208,6 +208,7 @@ struct scmi_chan_info { * @get_max_msg: Optional callback to provide max_msg dynamically * @max_msg: Maximum number of messages for the channel type (tx or rx) * that can be pending simultaneously in the system + * @xfer_init_buffers: Callback to initialize buffers for scmi_xfer * @send_message: Callback to send a message * @mark_txdone: Callback to mark tx as done * @fetch_response: Callback to fetch response @@ -222,6 +223,8 @@ struct scmi_transport_ops { int (*chan_free)(int id, void *p, void *data); int (*get_max_msg)(bool tx, struct scmi_chan_info *base_cinfo, int *max_msg); + int (*xfer_init_buffers)(struct scmi_chan_info *cinfo, + struct scmi_xfer *xfer, int max_msg_size); int (*send_message)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer); void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret); diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 5baa23789a49..27dd43dcff5b 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -640,12 +640,21 @@ static int __scmi_xfer_info_init(struct scmi_info *sinfo, /* Pre-initialize the buffer pointer to pre-allocated buffers */ for (i = 0, xfer = info->xfer_block; i < info->max_msg; i++, xfer++) { - xfer->rx.buf = devm_kcalloc(dev, sizeof(u8), desc->max_msg_size, - GFP_KERNEL); - if (!xfer->rx.buf) - return -ENOMEM; - - xfer->tx.buf = xfer->rx.buf; + if (desc->ops->xfer_init_buffers) { + int ret = desc->ops->xfer_init_buffers( + base_cinfo, xfer, desc->max_msg_size); + + if (ret) + return ret; + } else { + xfer->rx.buf = devm_kcalloc(dev, sizeof(u8), + desc->max_msg_size, + GFP_KERNEL); + if (!xfer->rx.buf) + return -ENOMEM; + + xfer->tx.buf = xfer->rx.buf; + } init_completion(&xfer->done); }