From ffbf23d50353915dc2622a3b7b4ddc678165f92d Mon Sep 17 00:00:00 2001 From: Daniel Baluta Date: Thu, 1 Aug 2019 12:56:36 +0300 Subject: firmware: imx: Add DSP IPC protocol interface Some of i.MX8 processors (e.g i.MX8QM, i.MX8QXP) contain the Tensilica HiFi4 DSP for advanced pre- and post-audio processing. The communication between Host CPU and DSP firmware is taking place using a shared memory area for message passing and a dedicated Messaging Unit for notifications. DSP IPC protocol offers a doorbell interface using imx-mailbox API. We use 4 MU channels (2 x TXDB, 2 x RXDB) to implement a request-reply protocol. Connection 0 (txdb0, rxdb0): - Host writes messasge to shared memory [SHMEM] - Host sends a request [MU] - DSP handles request [SHMEM] - DSP sends reply [MU] Connection 1 (txdb1, rxdb1): - DSP writes a message to shared memory [SHMEM] - DSP sends a request [MU] - Host handles request [SHMEM] - Host sends reply [MU] The protocol interface will be used by a Host client to communicate with the DSP. First client will be the i.MX8 part from Sound Open Firmware infrastructure. The protocol offers the following interface: On Tx: - imx_dsp_ring_doorbell, will be called to notify the DSP that it needs to handle a request. On Rx: - clients need to provide two callbacks: .handle_reply .handle_request - the callbacks will be used by the protocol on notification arrival from DSP. Signed-off-by: Daniel Baluta Reviewed-by: Oleksij Rempel Signed-off-by: Shawn Guo --- drivers/firmware/imx/Kconfig | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'drivers/firmware/imx/Kconfig') diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig index 42b566f8903f..0dbee32da4c6 100644 --- a/drivers/firmware/imx/Kconfig +++ b/drivers/firmware/imx/Kconfig @@ -1,4 +1,15 @@ # SPDX-License-Identifier: GPL-2.0-only +config IMX_DSP + bool "IMX DSP Protocol driver" + depends on IMX_MBOX + help + This enables DSP IPC protocol between host AP (Linux) + and the firmware running on DSP. + DSP exists on some i.MX8 processors (e.g i.MX8QM, i.MX8QXP). + + It acts like a doorbell. Client might use shared memory to + exchange information with DSP side. + config IMX_SCU bool "IMX SCU Protocol driver" depends on IMX_MBOX -- cgit v1.2.3