[PATCH 2/2] remoteproc: imx_dsp_rproc: add remoteproc driver for dsp on i.MX

[Shengjiu Wang <shengjiu.wang@nxp.com>]

Provide a basic driver to control DSP processor found on NXP i.MX8QM,
i.MX8QXP, i.MX8MP and i.MX8ULP.

Currently it is able to resolve addresses between DSP and main CPU,
start and stop the processor, suspend and resume.

The communication between DSP and main CPU is based on mailbox, there
are three mailbox channels (tx, rx, rxdb).

This driver was tested on NXP i.MX8QM, i.MX8QXP, i.MX8MP and i.MX8ULP.

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
---
 drivers/remoteproc/Kconfig         |   11 +
 drivers/remoteproc/Makefile        |    1 +
 drivers/remoteproc/imx_dsp_rproc.c | 1078 ++++++++++++++++++++++++++++
 3 files changed, 1090 insertions(+)
 create mode 100644 drivers/remoteproc/imx_dsp_rproc.c

diff --git a/drivers/remoteproc/Kconfig b/drivers/remoteproc/Kconfig
index 9a6eedc3994a..890a14e6f3f9 100644
--- a/drivers/remoteproc/Kconfig
+++ b/drivers/remoteproc/Kconfig
@@ -34,6 +34,17 @@ config IMX_REMOTEPROC
 
 	  It's safe to say N here.
 
+config IMX_DSP_REMOTEPROC
+	tristate "i.MX DSP remoteproc support"
+	depends on ARCH_MXC
+	depends on HAVE_ARM_SMCCC
+	select MAILBOX
+	help
+	  Say y here to support iMX's DSP remote processors via the remote
+	  processor framework.
+
+	  It's safe to say N here.
+
 config INGENIC_VPU_RPROC
 	tristate "Ingenic JZ47xx VPU remoteproc support"
 	depends on MIPS || COMPILE_TEST
diff --git a/drivers/remoteproc/Makefile b/drivers/remoteproc/Makefile
index bb26c9e4ef9c..37d5cb1c04bf 100644
--- a/drivers/remoteproc/Makefile
+++ b/drivers/remoteproc/Makefile
@@ -12,6 +12,7 @@ remoteproc-y				+= remoteproc_virtio.o
 remoteproc-y				+= remoteproc_elf_loader.o
 obj-$(CONFIG_REMOTEPROC_CDEV)		+= remoteproc_cdev.o
 obj-$(CONFIG_IMX_REMOTEPROC)		+= imx_rproc.o
+obj-$(CONFIG_IMX_DSP_REMOTEPROC)	+= imx_dsp_rproc.o
 obj-$(CONFIG_INGENIC_VPU_RPROC)		+= ingenic_rproc.o
 obj-$(CONFIG_MTK_SCP)			+= mtk_scp.o mtk_scp_ipi.o
 obj-$(CONFIG_OMAP_REMOTEPROC)		+= omap_remoteproc.o
diff --git a/drivers/remoteproc/imx_dsp_rproc.c b/drivers/remoteproc/imx_dsp_rproc.c
new file mode 100644
index 000000000000..2be6c734e7d5
--- /dev/null
+++ b/drivers/remoteproc/imx_dsp_rproc.c
@@ -0,0 +1,1078 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright 2021 NXP
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mailbox_client.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/regmap.h>
+#include <linux/remoteproc.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/workqueue.h>
+#include <linux/firmware/imx/sci.h>
+#include <dt-bindings/firmware/imx/rsrc.h>
+#include <linux/arm-smccc.h>
+
+#include "remoteproc_internal.h"
+#include "remoteproc_elf_helpers.h"
+
+enum imx_dsp_rp_mbox_messages {
+	RP_MBOX_SUSPEND_SYSTEM  = 0xFF11,
+	RP_MBOX_SUSPEND_ACK     = 0xFF12,
+	RP_MBOX_RESUME_SYSTEM   = 0xFF13,
+	RP_MBOX_RESUME_ACK      = 0xFF14,
+};
+
+#define DSP_RPROC_CLK_MAX 32
+
+#define REMOTE_IS_READY			BIT(0)
+#define REMOTE_READY_WAIT_MAX_RETRIES	500
+
+/* att flags */
+/* DSP own area. Can be mapped at probe */
+#define ATT_OWN		BIT(31)
+#define ATT_IRAM	BIT(30)
+
+/* i.MX8MP */
+/* DAP registers */
+#define IMX8M_DAP_DEBUG                0x28800000
+#define IMX8M_DAP_DEBUG_SIZE           (64 * 1024)
+#define IMX8M_DAP_PWRCTL               (0x4000 + 0x3020)
+#define IMX8M_PWRCTL_CORERESET         BIT(16)
+
+/* DSP audio mix registers */
+#define IMX8M_AudioDSP_REG0   0x100
+#define IMX8M_AudioDSP_REG1   0x104
+#define IMX8M_AudioDSP_REG2   0x108
+#define IMX8M_AudioDSP_REG3   0x10c
+
+#define IMX8M_AudioDSP_REG2_RUNSTALL  BIT(5)
+#define IMX8M_AudioDSP_REG2_PWAITMODE BIT(1)
+
+/* i.MX8ULP */
+#define IMX8ULP_SIM_LPAV_REG_SYSCTRL0       0x8
+#define IMX8ULP_SYSCTRL0_DSP_DBG_RST        BIT(25)
+#define IMX8ULP_SYSCTRL0_DSP_PLAT_CLK_EN    BIT(19)
+#define IMX8ULP_SYSCTRL0_DSP_PBCLK_EN       BIT(18)
+#define IMX8ULP_SYSCTRL0_DSP_CLK_EN         BIT(17)
+#define IMX8ULP_SYSCTRL0_DSP_RST            BIT(16)
+#define IMX8ULP_SYSCTRL0_DSP_OCD_HALT       BIT(14)
+#define IMX8ULP_SYSCTRL0_DSP_STALL          BIT(13)
+
+#define IMX8ULP_SIP_HIFI_XRDC         0xc200000e
+
+/* address translation table */
+struct imx_dsp_rproc_att {
+	u32 da;	/* device address (From Cortex M4 view)*/
+	u32 sa;	/* system bus address */
+	u32 size; /* size of reg range */
+	int flags;
+};
+
+/* Remote core start/stop method */
+enum imx_dsp_rproc_method {
+	/* Through syscon regmap */
+	IMX_DSP_MMIO,
+	IMX_DSP_SCU_API,
+};
+
+struct imx_dsp_rproc {
+	struct device			*dev;
+	struct regmap			*regmap;
+	struct rproc			*rproc;
+	const struct imx_dsp_rproc_dcfg	*dcfg;
+	struct clk			*clks[DSP_RPROC_CLK_MAX];
+	struct mbox_client		cl;
+	struct mbox_client		cl_rxdb;
+	struct mbox_chan		*tx_ch;
+	struct mbox_chan		*rx_ch;
+	struct mbox_chan		*rxdb_ch;
+	struct device			**pd_dev;
+	struct device_link		**pd_dev_link;
+	struct imx_sc_ipc		*ipc_handle;
+	struct work_struct		rproc_work;
+	struct workqueue_struct		*workqueue;
+	struct completion		pm_comp;
+	spinlock_t			mbox_lock;    /* lock for mbox */
+	int				num_domains;
+	u32				flags;
+};
+
+struct imx_dsp_rproc_dcfg {
+	u32				src_reg;
+	u32				src_mask;
+	u32				src_start;
+	u32				src_stop;
+	const struct imx_dsp_rproc_att	*att;
+	size_t				att_size;
+	enum imx_dsp_rproc_method	method;
+	int (*reset)(struct imx_dsp_rproc *priv);
+};
+
+static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8qm[] = {
+	/* dev addr , sys addr  , size	    , flags */
+	{ 0x596e8000, 0x556e8000, 0x00008000, ATT_OWN },
+	{ 0x596f0000, 0x556f0000, 0x00008000, ATT_OWN },
+	{ 0x596f8000, 0x556f8000, 0x00000800, ATT_OWN | ATT_IRAM},
+	{ 0x55700000, 0x55700000, 0x00070000, ATT_OWN },
+	/* DDR (Data) */
+	{ 0x80000000, 0x80000000, 0x60000000, 0},
+};
+
+static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8qxp[] = {
+	/* dev addr , sys addr  , size	    , flags */
+	{ 0x596e8000, 0x596e8000, 0x00008000, ATT_OWN },
+	{ 0x596f0000, 0x596f0000, 0x00008000, ATT_OWN },
+	{ 0x596f8000, 0x596f8000, 0x00000800, ATT_OWN | ATT_IRAM},
+	{ 0x59700000, 0x59700000, 0x00070000, ATT_OWN },
+	/* DDR (Data) */
+	{ 0x80000000, 0x80000000, 0x60000000, 0},
+};
+
+static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8mp[] = {
+	/* dev addr , sys addr  , size	    , flags */
+	{ 0x3b6e8000, 0x3b6e8000, 0x00008000, ATT_OWN },
+	{ 0x3b6f0000, 0x3b6f0000, 0x00008000, ATT_OWN },
+	{ 0x3b6f8000, 0x3b6f8000, 0x00000800, ATT_OWN | ATT_IRAM},
+	{ 0x3b700000, 0x3b700000, 0x00040000, ATT_OWN },
+	/* DDR (Data) */
+	{ 0x40000000, 0x40000000, 0x80000000, 0},
+};
+
+static const struct imx_dsp_rproc_att imx_dsp_rproc_att_imx8ulp[] = {
+	/* dev addr , sys addr  , size	    , flags */
+	{ 0x21170000, 0x21170000, 0x00010000, ATT_OWN | ATT_IRAM},
+	{ 0x21180000, 0x21180000, 0x00010000, ATT_OWN },
+	/* DDR (Data) */
+	{ 0x0c000000, 0x80000000, 0x10000000, 0},
+	{ 0x30000000, 0x90000000, 0x10000000, 0},
+};
+
+static int imx8mp_dsp_reset(struct imx_dsp_rproc *priv)
+{
+	void __iomem *dap = ioremap_wc(IMX8M_DAP_DEBUG, IMX8M_DAP_DEBUG_SIZE);
+	int pwrctl;
+
+	/* put DSP into reset and stall */
+	pwrctl = readl(dap + IMX8M_DAP_PWRCTL);
+	pwrctl |= IMX8M_PWRCTL_CORERESET;
+	writel(pwrctl, dap + IMX8M_DAP_PWRCTL);
+
+	/* keep reset asserted for 10 cycles */
+	usleep_range(1, 2);
+
+	regmap_update_bits(priv->regmap, IMX8M_AudioDSP_REG2,
+			   IMX8M_AudioDSP_REG2_RUNSTALL,
+			   IMX8M_AudioDSP_REG2_RUNSTALL);
+
+	/* take the DSP out of reset and keep stalled for FW loading */
+	pwrctl = readl(dap + IMX8M_DAP_PWRCTL);
+	pwrctl &= ~IMX8M_PWRCTL_CORERESET;
+	writel(pwrctl, dap + IMX8M_DAP_PWRCTL);
+
+	iounmap(dap);
+	return 0;
+}
+
+static int imx8ulp_dsp_reset(struct imx_dsp_rproc *priv)
+{
+	struct arm_smccc_res res;
+
+	regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
+			   IMX8ULP_SYSCTRL0_DSP_RST, IMX8ULP_SYSCTRL0_DSP_RST);
+	regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
+			   IMX8ULP_SYSCTRL0_DSP_STALL,
+			   IMX8ULP_SYSCTRL0_DSP_STALL);
+
+	arm_smccc_smc(IMX8ULP_SIP_HIFI_XRDC, 0, 0, 0, 0, 0, 0, 0, &res);
+
+	regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
+			   IMX8ULP_SYSCTRL0_DSP_RST, 0);
+	regmap_update_bits(priv->regmap, IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
+			   IMX8ULP_SYSCTRL0_DSP_DBG_RST, 0);
+
+	return 0;
+}
+
+static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8mp = {
+	.src_reg	= IMX8M_AudioDSP_REG2,
+	.src_mask	= IMX8M_AudioDSP_REG2_RUNSTALL,
+	.src_start	= 0,
+	.src_stop	= IMX8M_AudioDSP_REG2_RUNSTALL,
+	.att		= imx_dsp_rproc_att_imx8mp,
+	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8mp),
+	.method		= IMX_DSP_MMIO,
+	.reset          = imx8mp_dsp_reset,
+};
+
+static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8ulp = {
+	.src_reg	= IMX8ULP_SIM_LPAV_REG_SYSCTRL0,
+	.src_mask	= IMX8ULP_SYSCTRL0_DSP_STALL,
+	.src_start	= 0,
+	.src_stop	= IMX8ULP_SYSCTRL0_DSP_STALL,
+	.att		= imx_dsp_rproc_att_imx8ulp,
+	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8ulp),
+	.method		= IMX_DSP_MMIO,
+	.reset          = imx8ulp_dsp_reset,
+};
+
+static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qxp = {
+	.att		= imx_dsp_rproc_att_imx8qxp,
+	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8qxp),
+	.method		= IMX_DSP_SCU_API,
+};
+
+static const struct imx_dsp_rproc_dcfg imx_dsp_rproc_cfg_imx8qm = {
+	.att		= imx_dsp_rproc_att_imx8qm,
+	.att_size	= ARRAY_SIZE(imx_dsp_rproc_att_imx8qm),
+	.method		= IMX_DSP_SCU_API,
+};
+
+static int imx_dsp_rproc_ready(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+	int i;
+
+	if (!priv->rxdb_ch)
+		return 0;
+
+	for (i = 0; i < REMOTE_READY_WAIT_MAX_RETRIES; i++) {
+		if (priv->flags & REMOTE_IS_READY)
+			return 0;
+		usleep_range(100, 200);
+	}
+
+	return -ETIMEDOUT;
+}
+
+static int imx_dsp_rproc_start(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	struct device *dev = priv->dev;
+	int ret;
+
+	switch (dcfg->method) {
+	case IMX_DSP_MMIO:
+		ret = regmap_update_bits(priv->regmap,
+					 dcfg->src_reg,
+					 dcfg->src_mask,
+					 dcfg->src_start);
+		break;
+	case IMX_DSP_SCU_API:
+		ret = imx_sc_pm_cpu_start(priv->ipc_handle,
+					  IMX_SC_R_DSP,
+					  true,
+					  rproc->bootaddr);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	if (ret)
+		dev_err(dev, "Failed to enable remote core!\n");
+	else
+		ret = imx_dsp_rproc_ready(rproc);
+
+	return ret;
+}
+
+static int imx_dsp_rproc_stop(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	struct device *dev = priv->dev;
+	int ret = 0;
+
+	if (rproc->state == RPROC_CRASHED) {
+		priv->flags &= ~REMOTE_IS_READY;
+		return 0;
+	}
+
+	switch (dcfg->method) {
+	case IMX_DSP_MMIO:
+		ret = regmap_update_bits(priv->regmap, dcfg->src_reg, dcfg->src_mask,
+					 dcfg->src_stop);
+		break;
+	case IMX_DSP_SCU_API:
+		ret = imx_sc_pm_cpu_start(priv->ipc_handle,
+					  IMX_SC_R_DSP,
+					  false,
+					  rproc->bootaddr);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	if (ret)
+		dev_err(dev, "Failed to stop remote core\n");
+	else
+		priv->flags &= ~REMOTE_IS_READY;
+
+	return ret;
+}
+
+static int imx_dsp_rproc_sys_to_da(struct imx_dsp_rproc *priv, u64 sys,
+				   size_t len, u64 *da)
+{
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	int i;
+
+	/* parse address translation table */
+	for (i = 0; i < dcfg->att_size; i++) {
+		const struct imx_dsp_rproc_att *att = &dcfg->att[i];
+
+		if (sys >= att->sa && sys + len <= att->sa + att->size) {
+			unsigned int offset = sys - att->sa;
+
+			*da = att->da + offset;
+			return 0;
+		}
+	}
+
+	return -ENOENT;
+}
+
+static void imx_dsp_rproc_vq_work(struct work_struct *work)
+{
+	struct imx_dsp_rproc *priv = container_of(work, struct imx_dsp_rproc,
+						  rproc_work);
+
+	rproc_vq_interrupt(priv->rproc, 0);
+	rproc_vq_interrupt(priv->rproc, 1);
+}
+
+static void imx_dsp_rproc_rx_callback(struct mbox_client *cl, void *data)
+{
+	struct rproc *rproc = dev_get_drvdata(cl->dev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+	u32 message = (u32)(*(u32 *)data);
+
+	dev_dbg(priv->dev, "mbox msg: 0x%x\n", message);
+
+	switch (message) {
+	case RP_MBOX_SUSPEND_ACK:
+		complete(&priv->pm_comp);
+		break;
+	case RP_MBOX_RESUME_ACK:
+		complete(&priv->pm_comp);
+		break;
+	default:
+		queue_work(priv->workqueue, &priv->rproc_work);
+		break;
+	}
+}
+
+static void imx_dsp_rproc_rxdb_callback(struct mbox_client *cl, void *msg)
+{
+	struct rproc *rproc = dev_get_drvdata(cl->dev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->mbox_lock, flags);
+	priv->flags |= REMOTE_IS_READY;
+	spin_unlock_irqrestore(&priv->mbox_lock, flags);
+}
+
+static int imx_dsp_rproc_mbox_init(struct imx_dsp_rproc *priv)
+{
+	struct device *dev = priv->dev;
+	struct mbox_client *cl;
+	int ret;
+
+	if (!of_get_property(dev->of_node, "mbox-names", NULL))
+		return 0;
+
+	spin_lock_init(&priv->mbox_lock);
+
+	cl = &priv->cl;
+	cl->dev = dev;
+	cl->tx_block = true;
+	cl->tx_tout = 100;
+	cl->knows_txdone = false;
+	cl->rx_callback = imx_dsp_rproc_rx_callback;
+
+	priv->tx_ch = mbox_request_channel_byname(cl, "tx");
+	if (IS_ERR(priv->tx_ch)) {
+		ret = PTR_ERR(priv->tx_ch);
+		dev_dbg(cl->dev, "failed to request tx mailbox channel: %d\n",
+			ret);
+		goto err_out;
+	}
+
+	priv->rx_ch = mbox_request_channel_byname(cl, "rx");
+	if (IS_ERR(priv->rx_ch)) {
+		ret = PTR_ERR(priv->rx_ch);
+		dev_dbg(cl->dev, "failed to request rx mailbox channel: %d\n",
+			ret);
+		goto err_out;
+	}
+
+	cl = &priv->cl_rxdb;
+	cl->dev = dev;
+	cl->rx_callback = imx_dsp_rproc_rxdb_callback;
+
+	/*
+	 * RX door bell is used to receive the ready signal from remote
+	 * after the partition reset of A core.
+	 */
+	priv->rxdb_ch = mbox_request_channel_byname(cl, "rxdb");
+	if (IS_ERR(priv->rxdb_ch)) {
+		ret = PTR_ERR(priv->rxdb_ch);
+		dev_dbg(cl->dev, "failed to request mbox chan rxdb, ret %d\n",
+			ret);
+		goto err_out;
+	}
+
+	return 0;
+
+err_out:
+	if (!IS_ERR(priv->tx_ch))
+		mbox_free_channel(priv->tx_ch);
+	if (!IS_ERR(priv->rx_ch))
+		mbox_free_channel(priv->rx_ch);
+	if (!IS_ERR(priv->rxdb_ch))
+		mbox_free_channel(priv->rxdb_ch);
+
+	return ret;
+}
+
+static void imx_dsp_rproc_free_mbox(struct imx_dsp_rproc *priv)
+{
+	mbox_free_channel(priv->tx_ch);
+	mbox_free_channel(priv->rx_ch);
+	mbox_free_channel(priv->rxdb_ch);
+}
+
+static int imx_dsp_rproc_add_carveout(struct imx_dsp_rproc *priv)
+{
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	struct rproc *rproc = priv->rproc;
+	struct device *dev = priv->dev;
+	struct device_node *np = dev->of_node;
+	struct of_phandle_iterator it;
+	struct rproc_mem_entry *mem;
+	struct reserved_mem *rmem;
+	void __iomem *cpu_addr;
+	int a;
+	u64 da;
+
+	/* remap required addresses */
+	for (a = 0; a < dcfg->att_size; a++) {
+		const struct imx_dsp_rproc_att *att = &dcfg->att[a];
+
+		if (!(att->flags & ATT_OWN))
+			continue;
+
+		if (imx_dsp_rproc_sys_to_da(priv, att->sa, att->size, &da))
+			return -EINVAL;
+
+		cpu_addr = devm_ioremap_wc(dev, att->sa, att->size);
+
+		/* Register memory region */
+		mem = rproc_mem_entry_init(dev, cpu_addr, (dma_addr_t)att->sa,
+					   att->size, da,
+					   NULL,
+					   NULL,
+					   "dsp_mem");
+
+		if (mem)
+			rproc_coredump_add_segment(rproc, da, att->size);
+		else
+			return -ENOMEM;
+
+		rproc_add_carveout(rproc, mem);
+	}
+
+	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
+	while (of_phandle_iterator_next(&it) == 0) {
+		/*
+		 * Ignore the first memory region which will be used vdev buffer.
+		 * No need to do extra handlings, rproc_add_virtio_dev will handle it.
+		 */
+		if (!strcmp(it.node->name, "vdev0buffer"))
+			continue;
+
+		rmem = of_reserved_mem_lookup(it.node);
+		if (!rmem) {
+			dev_err(dev, "unable to acquire memory-region\n");
+			return -EINVAL;
+		}
+
+		if (imx_dsp_rproc_sys_to_da(priv, rmem->base, rmem->size, &da))
+			return -EINVAL;
+
+		cpu_addr = devm_ioremap_wc(dev, rmem->base, rmem->size);
+
+		/* Register memory region */
+		mem = rproc_mem_entry_init(dev, cpu_addr, (dma_addr_t)rmem->base,
+					   rmem->size, da,
+					   NULL,
+					   NULL,
+					   it.node->name);
+
+		if (mem)
+			rproc_coredump_add_segment(rproc, da, rmem->size);
+		else
+			return -ENOMEM;
+
+		rproc_add_carveout(rproc, mem);
+	}
+
+	return 0;
+}
+
+/*
+ * imx_dsp_rproc_elf_load_segments() specially check if memsz is zero
+ * or not.
+ */
+static int imx_dsp_rproc_elf_load_segments(struct rproc *rproc,
+					   const struct firmware *fw)
+{
+	struct device *dev = &rproc->dev;
+	u8 class = fw_elf_get_class(fw);
+	u32 elf_phdr_get_size = elf_size_of_phdr(class);
+	const u8 *elf_data = fw->data;
+	const void *ehdr, *phdr;
+	int i, ret = 0;
+	u16 phnum;
+
+	ehdr = elf_data;
+	phnum = elf_hdr_get_e_phnum(class, ehdr);
+	phdr = elf_data + elf_hdr_get_e_phoff(class, ehdr);
+
+	/* go through the available ELF segments */
+	for (i = 0; i < phnum; i++, phdr += elf_phdr_get_size) {
+		u64 da = elf_phdr_get_p_paddr(class, phdr);
+		u64 memsz = elf_phdr_get_p_memsz(class, phdr);
+		u64 filesz = elf_phdr_get_p_filesz(class, phdr);
+		u64 offset = elf_phdr_get_p_offset(class, phdr);
+		u32 type = elf_phdr_get_p_type(class, phdr);
+		void *ptr;
+		bool is_iomem;
+
+		if (type != PT_LOAD || !memsz)
+			continue;
+
+		dev_dbg(dev, "phdr: type %d da 0x%llx memsz 0x%llx filesz 0x%llx\n",
+			type, da, memsz, filesz);
+
+		if (filesz > memsz) {
+			dev_err(dev, "bad phdr filesz 0x%llx memsz 0x%llx\n",
+				filesz, memsz);
+			ret = -EINVAL;
+			break;
+		}
+
+		if (offset + filesz > fw->size) {
+			dev_err(dev, "truncated fw: need 0x%llx avail 0x%zx\n",
+				offset + filesz, fw->size);
+			ret = -EINVAL;
+			break;
+		}
+
+		if (!rproc_u64_fit_in_size_t(memsz)) {
+			dev_err(dev, "size (%llx) does not fit in size_t type\n",
+				memsz);
+			ret = -EOVERFLOW;
+			break;
+		}
+
+		/* grab the kernel address for this device address */
+		ptr = rproc_da_to_va(rproc, da, memsz, &is_iomem);
+		if (!ptr) {
+			dev_err(dev, "bad phdr da 0x%llx mem 0x%llx\n", da,
+				memsz);
+			ret = -EINVAL;
+			break;
+		}
+
+		/* put the segment where the remote processor expects it */
+		if (filesz)
+			memcpy(ptr, elf_data + offset, filesz);
+
+		/*
+		 * Zero out remaining memory for this segment.
+		 *
+		 * This isn't strictly required since dma_alloc_coherent already
+		 * did this for us. albeit harmless, we may consider removing
+		 * this.
+		 */
+		if (memsz > filesz)
+			memset(ptr + filesz, 0, memsz - filesz);
+	}
+
+	return ret;
+}
+
+static int imx_dsp_rproc_prepare(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+	struct device *dev = priv->dev;
+	struct rproc_mem_entry *carveout;
+	int ret;
+
+	ret = imx_dsp_rproc_add_carveout(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_rproc_add_carveout\n");
+		return ret;
+	}
+
+	pm_runtime_get_sync(dev);
+
+	/* clear buffers */
+	list_for_each_entry(carveout, &rproc->carveouts, node) {
+		if (carveout->va)
+			memset(carveout->va, 0, carveout->len);
+	}
+
+	return  0;
+}
+
+static int imx_dsp_rproc_unprepare(struct rproc *rproc)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	pm_runtime_put_sync(priv->dev);
+
+	return  0;
+}
+
+static void imx_dsp_rproc_kick(struct rproc *rproc, int vqid)
+{
+	struct imx_dsp_rproc *priv = rproc->priv;
+	int err;
+	__u32 mmsg;
+
+	if (!priv->tx_ch) {
+		dev_err(priv->dev, "No initialized mbox tx channel\n");
+		return;
+	}
+
+	/*
+	 * Send the index of the triggered virtqueue as the mu payload.
+	 * Let remote processor know which virtqueue is used.
+	 */
+	mmsg = vqid;
+
+	err = mbox_send_message(priv->tx_ch, (void *)&mmsg);
+	if (err < 0)
+		dev_err(priv->dev, "%s: failed (%d, err:%d)\n",
+			__func__, vqid, err);
+}
+
+static const struct rproc_ops imx_dsp_rproc_ops = {
+	.prepare	= imx_dsp_rproc_prepare,
+	.unprepare	= imx_dsp_rproc_unprepare,
+	.start		= imx_dsp_rproc_start,
+	.stop		= imx_dsp_rproc_stop,
+	.kick		= imx_dsp_rproc_kick,
+	.load		= imx_dsp_rproc_elf_load_segments,
+	.parse_fw	= rproc_elf_load_rsc_table,
+	.sanity_check	= rproc_elf_sanity_check,
+	.get_boot_addr	= rproc_elf_get_boot_addr,
+};
+
+static int imx_dsp_attach_pm_domains(struct imx_dsp_rproc *priv)
+{
+	struct device *dev = priv->dev;
+	int ret, i;
+
+	priv->num_domains = of_count_phandle_with_args(dev->of_node,
+						       "power-domains",
+						       "#power-domain-cells");
+	if (priv->num_domains <= 1)
+		return 0;
+
+	priv->pd_dev = devm_kmalloc_array(dev, priv->num_domains,
+					  sizeof(*priv->pd_dev),
+					  GFP_KERNEL);
+	if (!priv->pd_dev)
+		return -ENOMEM;
+
+	priv->pd_dev_link = devm_kmalloc_array(dev, priv->num_domains,
+					       sizeof(*priv->pd_dev_link),
+					       GFP_KERNEL);
+	if (!priv->pd_dev_link)
+		return -ENOMEM;
+
+	for (i = 0; i < priv->num_domains; i++) {
+		priv->pd_dev[i] = dev_pm_domain_attach_by_id(dev, i);
+		if (IS_ERR(priv->pd_dev[i]))
+			return PTR_ERR(priv->pd_dev[i]);
+
+		priv->pd_dev_link[i] = device_link_add(dev,
+						       priv->pd_dev[i],
+						       DL_FLAG_STATELESS |
+						       DL_FLAG_PM_RUNTIME |
+						       DL_FLAG_RPM_ACTIVE);
+		if (IS_ERR(priv->pd_dev_link[i])) {
+			dev_pm_domain_detach(priv->pd_dev[i], false);
+			ret = PTR_ERR(priv->pd_dev_link[i]);
+			goto detach_pm;
+		}
+	}
+
+	return 0;
+
+detach_pm:
+	while (--i >= 0) {
+		device_link_del(priv->pd_dev_link[i]);
+		dev_pm_domain_detach(priv->pd_dev[i], false);
+	}
+
+	return ret;
+}
+
+static int imx_dsp_detach_pm_domains(struct imx_dsp_rproc *priv)
+{
+	int i;
+
+	if (priv->num_domains <= 1)
+		return 0;
+
+	for (i = 0; i < priv->num_domains; i++) {
+		device_link_del(priv->pd_dev_link[i]);
+		dev_pm_domain_detach(priv->pd_dev[i], false);
+	}
+
+	return 0;
+}
+
+static int imx_dsp_rproc_detect_mode(struct imx_dsp_rproc *priv)
+{
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	struct device *dev = priv->dev;
+	struct regmap *regmap;
+	int ret = 0;
+
+	switch (dcfg->method) {
+	case IMX_DSP_SCU_API:
+		ret = imx_scu_get_handle(&priv->ipc_handle);
+		if (ret)
+			return ret;
+		return 0;
+	case IMX_DSP_MMIO:
+		regmap = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon");
+		if (IS_ERR(regmap)) {
+			dev_err(dev, "failed to find syscon\n");
+			return PTR_ERR(regmap);
+		}
+
+		priv->regmap = regmap;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+static const char *imx_dsp_clks_names[DSP_RPROC_CLK_MAX] = {
+	/* DSP clocks */
+	"dsp_clk1", "dsp_clk2", "dsp_clk3", "dsp_clk4", "dsp_clk5", "dsp_clk6",
+	"dsp_clk7", "dsp_clk8",
+
+	/* Peripheral clocks */
+	"per_clk1", "per_clk2", "per_clk3", "per_clk4", "per_clk5", "per_clk6",
+	"per_clk7", "per_clk8", "per_clk9", "per_clk10", "per_clk11", "per_clk12",
+	"per_clk13", "per_clk14", "per_clk15", "per_clk16", "per_clk17", "per_clk18",
+};
+
+static int imx_dsp_rproc_clk_get(struct imx_dsp_rproc *priv)
+{
+	int i;
+
+	for (i = 0; i < DSP_RPROC_CLK_MAX; i++) {
+		priv->clks[i] = devm_clk_get_optional(priv->dev,
+						      imx_dsp_clks_names[i]);
+		if (IS_ERR(priv->clks[i])) {
+			dev_err(priv->dev, "Failed to get clock %s\n",
+				imx_dsp_clks_names[i]);
+			return PTR_ERR(priv->clks[i]);
+		}
+	}
+
+	return 0;
+}
+
+static int imx_dsp_rproc_clk_enable(struct imx_dsp_rproc *priv)
+{
+	int i, ret;
+
+	for (i = 0; i < DSP_RPROC_CLK_MAX; i++) {
+		ret = clk_prepare_enable(priv->clks[i]);
+		if (ret < 0) {
+			dev_err(priv->dev, "Failed to enable clk %s\n",
+				imx_dsp_clks_names[i]);
+			goto err_dsp_clks;
+		}
+	}
+
+	return 0;
+
+err_dsp_clks:
+	while (--i >= 0)
+		clk_disable_unprepare(priv->clks[i]);
+
+	return ret;
+}
+
+static void imx_dsp_rproc_clk_disable(struct imx_dsp_rproc *priv)
+{
+	int i;
+
+	for (i = 0; i < DSP_RPROC_CLK_MAX; i++)
+		clk_disable_unprepare(priv->clks[i]);
+}
+
+static int imx_dsp_rproc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	const struct imx_dsp_rproc_dcfg *dcfg;
+	struct imx_dsp_rproc *priv;
+	struct rproc *rproc;
+	const char *fw_name;
+	int ret;
+
+	dcfg = of_device_get_match_data(dev);
+	if (!dcfg)
+		return -ENODEV;
+
+	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
+	if (ret) {
+		dev_err(dev, "failed to parse firmware-name property, ret = %d\n",
+			ret);
+		return ret;
+	}
+
+	rproc = rproc_alloc(dev, "imx-dsp-rproc", &imx_dsp_rproc_ops, fw_name,
+			    sizeof(*priv));
+	if (!rproc)
+		return -ENOMEM;
+
+	priv = rproc->priv;
+	priv->rproc = rproc;
+	priv->dcfg = dcfg;
+	priv->dev = dev;
+
+	dev_set_drvdata(dev, rproc);
+
+	priv->workqueue = create_workqueue(dev_name(dev));
+	if (!priv->workqueue) {
+		dev_err(dev, "cannot create workqueue\n");
+		ret = -ENOMEM;
+		goto err_wkq;
+	}
+
+	INIT_WORK(&priv->rproc_work, imx_dsp_rproc_vq_work);
+
+	ret = imx_dsp_rproc_detect_mode(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_rproc_detect_mode\n");
+		goto err_detect;
+	}
+
+	ret = imx_dsp_attach_pm_domains(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_attach_pm_domains\n");
+		goto err_pm;
+	}
+
+	ret = imx_dsp_rproc_clk_get(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_rproc_clk_get\n");
+		goto err_clk_get;
+	}
+
+	init_completion(&priv->pm_comp);
+	rproc->auto_boot = false;
+	ret = rproc_add(rproc);
+	if (ret) {
+		dev_err(dev, "rproc_add failed\n");
+		goto err_rproc_add;
+	}
+
+	pm_runtime_enable(dev);
+
+	return 0;
+
+err_rproc_add:
+err_clk_get:
+	imx_dsp_detach_pm_domains(priv);
+err_pm:
+err_detect:
+	destroy_workqueue(priv->workqueue);
+err_wkq:
+	rproc_free(rproc);
+
+	return ret;
+}
+
+static int imx_dsp_rproc_remove(struct platform_device *pdev)
+{
+	struct rproc *rproc = platform_get_drvdata(pdev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	pm_runtime_disable(&pdev->dev);
+	rproc_del(rproc);
+	imx_dsp_detach_pm_domains(priv);
+	destroy_workqueue(priv->workqueue);
+	rproc_free(rproc);
+
+	return 0;
+}
+
+/* pm runtime */
+static int imx_dsp_runtime_resume(struct device *dev)
+{
+	struct rproc *rproc = dev_get_drvdata(dev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+	const struct imx_dsp_rproc_dcfg *dcfg = priv->dcfg;
+	int ret;
+
+	ret = imx_dsp_rproc_mbox_init(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_rproc_mbox_init\n");
+		return ret;
+	}
+
+	ret = imx_dsp_rproc_clk_enable(priv);
+	if (ret) {
+		dev_err(dev, "failed on imx_dsp_rproc_clk_enable\n");
+		return ret;
+	}
+
+	/* reset DSP if needed */
+	if (dcfg->reset)
+		dcfg->reset(priv);
+
+	return 0;
+}
+
+static int imx_dsp_runtime_suspend(struct device *dev)
+{
+	struct rproc *rproc = dev_get_drvdata(dev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+
+	imx_dsp_rproc_clk_disable(priv);
+
+	imx_dsp_rproc_free_mbox(priv);
+
+	return 0;
+}
+
+static void imx_dsp_load_firmware(const struct firmware *fw, void *context)
+{
+	struct rproc *rproc = context;
+	int ret;
+
+	/* load the ELF segments to memory */
+	ret = rproc_load_segments(rproc, fw);
+	if (ret)
+		goto out;
+
+	/* power up the remote processor */
+	ret = rproc->ops->start(rproc);
+	if (ret)
+		goto out;
+
+	/* same flow as first start */
+	rproc->ops->kick(rproc, 0);
+
+out:
+	release_firmware(fw);
+}
+
+static int imx_dsp_suspend(struct device *dev)
+{
+	struct rproc *rproc = dev_get_drvdata(dev);
+	struct imx_dsp_rproc *priv = rproc->priv;
+	__u32 mmsg = RP_MBOX_SUSPEND_SYSTEM;
+	int ret;
+
+	if (rproc->state == RPROC_RUNNING) {
+		reinit_completion(&priv->pm_comp);
+
+		ret = mbox_send_message(priv->tx_ch, (void *)&mmsg);
+		if (ret < 0) {
+			dev_err(dev, "PM mbox_send_message failed: %d\n", ret);
+			return ret;
+		}
+
+		if (!wait_for_completion_timeout(&priv->pm_comp, msecs_to_jiffies(100)))
+			return -EBUSY;
+	}
+
+	return pm_runtime_force_suspend(dev);
+}
+
+static int imx_dsp_resume(struct device *dev)
+{
+	struct rproc *rproc = dev_get_drvdata(dev);
+	int ret = 0;
+
+	ret = pm_runtime_force_resume(dev);
+	if (ret)
+		return ret;
+
+	if (rproc->state == RPROC_RUNNING) {
+		/*TODO: load firmware and start */
+		ret = request_firmware_nowait(THIS_MODULE,
+					      FW_ACTION_UEVENT,
+					      rproc->firmware,
+					      dev,
+					      GFP_KERNEL,
+					      rproc,
+					      imx_dsp_load_firmware);
+		if (ret < 0) {
+			dev_err(dev, "load firmware failed: %d\n", ret);
+			goto err;
+		}
+	}
+
+	return 0;
+
+err:
+	pm_runtime_force_suspend(dev);
+
+	return ret;
+}
+
+static const struct dev_pm_ops imx_dsp_rproc_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(imx_dsp_suspend, imx_dsp_resume)
+	SET_RUNTIME_PM_OPS(imx_dsp_runtime_suspend,
+			   imx_dsp_runtime_resume, NULL)
+};
+
+static const struct of_device_id imx_dsp_rproc_of_match[] = {
+	{ .compatible = "fsl,imx8qxp-hifi4", .data = &imx_dsp_rproc_cfg_imx8qxp },
+	{ .compatible = "fsl,imx8qm-hifi4",  .data = &imx_dsp_rproc_cfg_imx8qm },
+	{ .compatible = "fsl,imx8mp-hifi4",  .data = &imx_dsp_rproc_cfg_imx8mp },
+	{ .compatible = "fsl,imx8ulp-hifi4", .data = &imx_dsp_rproc_cfg_imx8ulp },
+	{},
+};
+MODULE_DEVICE_TABLE(of, imx_dsp_rproc_of_match);
+
+static struct platform_driver imx_dsp_rproc_driver = {
+	.probe = imx_dsp_rproc_probe,
+	.remove = imx_dsp_rproc_remove,
+	.driver = {
+		.name = "imx-dsp-rproc",
+		.of_match_table = imx_dsp_rproc_of_match,
+		.pm = &imx_dsp_rproc_pm_ops,
+	},
+};
+module_platform_driver(imx_dsp_rproc_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("i.MX HiFi Core Remote Processor Control Driver");
+MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");
-- 
2.17.1