Re: [PATCH v2 2/2] remoteproc: imx_dsp_rproc: add remoteproc driver for dsp on i.MX

From: Mathieu Poirier
Date: Tue Aug 31 2021 - 14:02:14 EST


Hi Shengjiu,

On Wed, Aug 25, 2021 at 03:28:36PM +0800, Shengjiu Wang wrote:
> 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@xxxxxxx>
> ---
> changes in v2:
> - change syscon to fsl,dsp-ctrl
>
> 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..ce0596694122
> --- /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>

Alphabetical order

> +#include <linux/workqueue.h>
> +#include <linux/firmware/imx/sci.h>

Same

> +#include <dt-bindings/firmware/imx/rsrc.h>
> +#include <linux/arm-smccc.h>

Same

> +
> +#include "remoteproc_internal.h"
> +#include "remoteproc_elf_helpers.h"

Same

> +
> +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

For all of the above defines, either align them all or not at all.

> +
> +/* 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;
> +};

This is already defined in imx_rproc.c - why do we need another definition here?

> +
> +/* Remote core start/stop method */
> +enum imx_dsp_rproc_method {
> + /* Through syscon regmap */
> + IMX_DSP_MMIO,
> + IMX_DSP_SCU_API,
> +};

>From where I stand it would be worth merging the above with imx_rproc_method
found in imx_rproc.c. I don't see a need for duplication.

> +
> +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;

The above is similar to imx_rproc_cfg. As such:

struct imx_dsp_rproc_dcfg {
struct imx_rproc_cfg *dcfg;
int (*reset)(struct imx_dsp_rproc *priv);
};

> + 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");

Stacking

> +
> + 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);

Stacking

> +
> + 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, "fsl,dsp-ctrl");
> + if (IS_ERR(regmap)) {
> + dev_err(dev, "failed to find syscon\n");
> + return PTR_ERR(regmap);
> + }
> +
> + priv->regmap = regmap;
> + default:
> + break;

Shouldn't it be an error if neither SCU of MMIO methods are specified?

> + }
> +
> + 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]);

Please use the devm_clk_bulk_xyz() API.

> + 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:

Name the gotos in relation to what they do rather than where they come from,
something like "detach_domains". That way you don't need multiple goto
statements that clutter the code.

> + imx_dsp_detach_pm_domains(priv);
> +err_pm:
> +err_detect:

Same

> + 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);

Why is the mailbox setup and destroyed with every PM cycle? I find an overall
lack of comments makes this driver difficult to review, resulting in having to
spend more time to look at and understand the code. I will have to continue
tomorrow because, well, I ran out of time.

Mathieu

> + 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@xxxxxxx>");
> --
> 2.17.1
>