From nobody Tue Apr 7 17:16:28 2026 Received: from inva020.nxp.com (inva020.nxp.com [92.121.34.13]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B3E8639C65B; Fri, 6 Mar 2026 13:28:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=92.121.34.13 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772803693; cv=none; b=B/Qp2tcNDW8l8WnS1JVKtyLdfbN5bqCW9R4RCTPZThota9jDltc4ULeBO2X0CwPseiiH6+LIZOir06rclv6hcEOslW4IUZjelDFbhJRI5nNjiYQu/7wrovqO1N3Q/JFXUHXV9Nhi6FpbuHcpfizwci2fPzrUDP22ca7NlyHT02k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772803693; c=relaxed/simple; bh=Jty6B0ytRRom/v7JJudk9QB5erW8GFmasf1vl2KeMcs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=gysN7mVRtN8AH4WFe/hdGhbFWlKu3Txafeu1Ly4Na1iy6norDcdjJSSvXg/DEbFg+FaEkLcE01zt7yO5xP6x6BCKXo/P94ysI2NO7PfQKGal+JT2N4xI3Nr/rXWi6ptO4zy/SooO14QmaKO7Eo6L2o/6dt91Tc1zrbCIQNHGLv0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com; spf=pass smtp.mailfrom=nxp.com; arc=none smtp.client-ip=92.121.34.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nxp.com Received: from inva020.nxp.com (localhost [127.0.0.1]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 53E291A011E; Fri, 6 Mar 2026 14:28:10 +0100 (CET) Received: from inva024.eu-rdc02.nxp.com (inva024.eu-rdc02.nxp.com [134.27.226.22]) by inva020.eu-rdc02.nxp.com (Postfix) with ESMTP id 3C2171A010F; Fri, 6 Mar 2026 14:28:10 +0100 (CET) Received: from lsv15149.swis.ro-buh01.nxp.com (lsv15149.swis.ro-buh01.nxp.com [10.162.246.145]) by inva024.eu-rdc02.nxp.com (Postfix) with ESMTP id C22D220270; Fri, 6 Mar 2026 14:28:08 +0100 (CET) From: Ioana Ciocoi-Radulescu Date: Fri, 06 Mar 2026 15:27:23 +0200 Subject: [PATCH v2 6/9] accel/neutron: Add mailbox support Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260306-neutron-v2-6-3019bd8c91ef@nxp.com> References: <20260306-neutron-v2-0-3019bd8c91ef@nxp.com> In-Reply-To: <20260306-neutron-v2-0-3019bd8c91ef@nxp.com> To: Oded Gabbay , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Sumit Semwal , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Frank Li , =?utf-8?q?Christian_K=C3=B6nig?= Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, Jiwei Fu , Forrest Shi , Alexandru Taran , Daniel Baluta , Ioana Ciocoi-Radulescu X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772803681; l=4796; i=ruxandra.radulescu@nxp.com; s=20260204; h=from:subject:message-id; bh=Jty6B0ytRRom/v7JJudk9QB5erW8GFmasf1vl2KeMcs=; b=PB4TlUF+leh2OekYOU7U0kWWmeLsSe45WOXmQtld7wmvZo/tOAUFlSuUQPelI+WGFFpp/b5/0 Oltg6BknDsUC+cHr3/UG2GXxESoitk7j2nv1rCbQ/LNaWketzH6710e X-Developer-Key: i=ruxandra.radulescu@nxp.com; a=ed25519; pk=zoq4b4OYR0c4faAH97xoTxdr6vfR8OvPbS+Cx0XhIBY= X-Virus-Scanned: ClamAV using ClamSMTP The driver communicates with the Neutron firmware via eight register-backed mailboxes. A subset of the mailbox registers are used to pass commands from driver to Neutron, while the rest are written by Neutron firmware with status/ack info. Signed-off-by: Jiwei Fu Signed-off-by: Ioana Ciocoi-Radulescu --- drivers/accel/neutron/Makefile | 3 ++- drivers/accel/neutron/neutron_device.c | 4 +++ drivers/accel/neutron/neutron_mailbox.c | 47 +++++++++++++++++++++++++++++= ++++ drivers/accel/neutron/neutron_mailbox.h | 42 +++++++++++++++++++++++++++++ 4 files changed, 95 insertions(+), 1 deletion(-) diff --git a/drivers/accel/neutron/Makefile b/drivers/accel/neutron/Makefile index d4298c7a8535..192ed896a9f9 100644 --- a/drivers/accel/neutron/Makefile +++ b/drivers/accel/neutron/Makefile @@ -5,4 +5,5 @@ obj-$(CONFIG_DRM_ACCEL_NXP_NEUTRON) :=3D neutron.o neutron-y :=3D \ neutron_driver.o \ neutron_device.o \ - neutron_gem.o + neutron_gem.o \ + neutron_mailbox.o diff --git a/drivers/accel/neutron/neutron_device.c b/drivers/accel/neutron= /neutron_device.c index 61b3c96b4996..e5c09105be99 100644 --- a/drivers/accel/neutron/neutron_device.c +++ b/drivers/accel/neutron/neutron_device.c @@ -7,6 +7,7 @@ #include =20 #include "neutron_device.h" +#include "neutron_mailbox.h" =20 void neutron_enable_irq(struct neutron_device *ndev) { @@ -148,6 +149,9 @@ int neutron_boot(struct neutron_device *ndev) if (ret) return ret; =20 + /* Prepare device to receive jobs */ + neutron_mbox_reset_state(ndev); + ndev->flags |=3D NEUTRON_BOOTED; =20 return 0; diff --git a/drivers/accel/neutron/neutron_mailbox.c b/drivers/accel/neutro= n/neutron_mailbox.c new file mode 100644 index 000000000000..327ef2e8081d --- /dev/null +++ b/drivers/accel/neutron/neutron_mailbox.c @@ -0,0 +1,47 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* Copyright 2023, 2025-2026 NXP */ + +#include + +#include "neutron_device.h" +#include "neutron_mailbox.h" + +#define NEUTRON_MBOX_FW_STATUS(dev) NEUTRON_REG(dev, MBOX0) +#define NEUTRON_MBOX_FW_ERRCODE(dev) NEUTRON_REG(dev, MBOX1) +#define NEUTRON_MBOX_CMD_ID(dev) NEUTRON_REG(dev, MBOX3) +#define NEUTRON_MBOX_CMD_ARG_BASE(dev) NEUTRON_REG(dev, MBOX4) +#define NEUTRON_MBOX_CMD_ARG(dev, i) (NEUTRON_MBOX_CMD_ARG_BASE(dev) + (i)= * 4) + +int neutron_mbox_send_cmd(struct neutron_device *ndev, struct neutron_mbox= _cmd *cmd) +{ + u32 status; + int i; + + /* Make sure Neutron is ready to receive commands */ + status =3D readl_relaxed(NEUTRON_MBOX_FW_STATUS(ndev)); + if (status !=3D NEUTRON_FW_STATUS_RESET) + return -EBUSY; + + for (i =3D 0; i < NEUTRON_MBOX_MAX_CMD_ARGS; i++) + writel_relaxed(cmd->args[i], NEUTRON_MBOX_CMD_ARG(ndev, i)); + writel(cmd->id, NEUTRON_MBOX_CMD_ID(ndev)); + + return 0; +} + +int neutron_mbox_reset_state(struct neutron_device *ndev) +{ + u32 status; + + writel_relaxed(NEUTRON_CMD_RESET_STATE, NEUTRON_MBOX_CMD_ID(ndev)); + + return readl_poll_timeout(NEUTRON_MBOX_FW_STATUS(ndev), status, + status =3D=3D NEUTRON_FW_STATUS_RESET, + 100, 100 * USEC_PER_MSEC); +} + +void neutron_mbox_read_state(struct neutron_device *ndev, struct neutron_m= box_state *state) +{ + state->status =3D readl_relaxed(NEUTRON_MBOX_FW_STATUS(ndev)); + state->err_code =3D readl_relaxed(NEUTRON_MBOX_FW_ERRCODE(ndev)); +} diff --git a/drivers/accel/neutron/neutron_mailbox.h b/drivers/accel/neutro= n/neutron_mailbox.h new file mode 100644 index 000000000000..4fe40a2f6a0c --- /dev/null +++ b/drivers/accel/neutron/neutron_mailbox.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* Copyright 2023, 2025-2026 NXP */ + +#ifndef __NEUTRON_MAILBOX_H__ +#define __NEUTRON_MAILBOX_H__ + +#include + +struct neutron_device; + +/* Device (firmware) status magic values */ +enum neutron_mbox_fwstat { + NEUTRON_FW_STATUS_RESET =3D 0, + NEUTRON_FW_STATUS_ACK =3D 0xA3, + NEUTRON_FW_STATUS_DONE =3D 0xAD0, +}; + +/* Firmware command opcodes */ +enum neutron_mbox_cmdid { + NEUTRON_CMD_INFERENCE =3D 0x269, + NEUTRON_CMD_RESET_STATE =3D 0x23637, +}; + +#define NEUTRON_MBOX_MAX_CMD_ARGS 4 + +/* Firmware command */ +struct neutron_mbox_cmd { + enum neutron_mbox_cmdid id; + u32 args[NEUTRON_MBOX_MAX_CMD_ARGS]; +}; + +/* Device state */ +struct neutron_mbox_state { + enum neutron_mbox_fwstat status; + u32 err_code; +}; + +int neutron_mbox_send_cmd(struct neutron_device *ndev, struct neutron_mbox= _cmd *cmd); +void neutron_mbox_read_state(struct neutron_device *ndev, struct neutron_m= box_state *state); +int neutron_mbox_reset_state(struct neutron_device *ndev); + +#endif /* __NEUTRON_MAILBOX_H__ */ --=20 2.34.1