Hi Marc,
> -----Original Message-----
> From: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
> Sent: 2020年10月19日 16:16
> To: Joakim Zhang <qiangqing.zhang@xxxxxxx>; robh+dt@xxxxxxxxxx;
> shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx
> Cc: kernel@xxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx>; Ying Liu
> <victor.liu@xxxxxxx>; linux-can@xxxxxxxxxxxxxxx; Pankaj Bansal
> <pankaj.bansal@xxxxxxx>; netdev@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH V2 8/8] can: flexcan: add CAN wakeup function for
> i.MX8QM
>
> On 10/19/20 5:57 PM, Joakim Zhang wrote:
> > The System Controller Firmware (SCFW) is a low-level system function
> > which runs on a dedicated Cortex-M core to provide power, clock, and
> > resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
> > (QM, QP), and i.MX8QX (QXP, DX). SCU driver manages the IPC interface
> > between host CPU and the SCU firmware running on M4.
> >
> > For i.MX8QM, stop mode request is controlled by System Controller
> > Unit(SCU) firmware, this patch introduces
> > FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW quirk for this function.
> >
> > Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> > ---
> > drivers/net/can/flexcan.c | 131
> > +++++++++++++++++++++++++++++++++-----
> > 1 file changed, 114 insertions(+), 17 deletions(-)
> >
> > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
> > index c0cdee904ca7..8ad5065c918f 100644
> > --- a/drivers/net/can/flexcan.c
> > +++ b/drivers/net/can/flexcan.c
> > @@ -9,6 +9,7 @@
> > //
> > // Based on code originally by Andrey Volkov <avolkov@xxxxxxxxxxxx>
> >
> > +#include <dt-bindings/firmware/imx/rsrc.h>
> > #include <linux/bitfield.h>
> > #include <linux/can.h>
> > #include <linux/can/dev.h>
> > @@ -17,6 +18,7 @@
> > #include <linux/can/rx-offload.h>
> > #include <linux/clk.h>
> > #include <linux/delay.h>
> > +#include <linux/firmware/imx/sci.h>
> > #include <linux/interrupt.h>
> > #include <linux/io.h>
> > #include <linux/mfd/syscon.h>
> > @@ -203,6 +205,8 @@
> >
> > #define FLEXCAN_TIMEOUT_US (250)
> >
> > +#define FLEXCAN_IMX_SC_R_CAN(x) (IMX_SC_R_CAN_0 + (x))
>
> Why not move it into the appropriate svc header file?
Sorry, not quite understand. Which file do you mean the appropriate svc header file? Is it include/dt-bindings/firmware/imx/rsrc.h?
After glancing the header file under include/linux/firmware/imx, have not found the appropriate svc header. Could you please explain more?
> > +
> > /* FLEXCAN hardware feature flags
> > *
> > * Below is some version info we got:
> > @@ -242,6 +246,8 @@
> > #define FLEXCAN_QUIRK_SUPPORT_FD BIT(9)
> > /* support memory detection and correction */ #define
> > FLEXCAN_QUIRK_SUPPORT_ECC BIT(10)
> > +/* Setup stop mode with SCU firmware to support wakeup */ #define
> > +FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW BIT(11)
> >
> > /* Structure of the message buffer */ struct flexcan_mb { @@ -347,6
> > +353,7 @@ struct flexcan_priv {
> > u8 mb_count;
> > u8 mb_size;
> > u8 clk_src; /* clock source of CAN Protocol Engine */
> > + u8 can_idx;
> >
> > u64 rx_mask;
> > u64 tx_mask;
> > @@ -358,6 +365,9 @@ struct flexcan_priv {
> > struct regulator *reg_xceiver;
> > struct flexcan_stop_mode stm;
> >
> > + /* IPC handle when setup stop mode by System Controller firmware(scfw)
> */
> > + struct imx_sc_ipc *sc_ipc_handle;
> > +
> > /* Read and Write APIs */
> > u32 (*read)(void __iomem *addr);
> > void (*write)(u32 val, void __iomem *addr); @@ -387,7 +397,7 @@
> > static const struct flexcan_devtype_data fsl_imx6q_devtype_data = {
> > static const struct flexcan_devtype_data fsl_imx8qm_devtype_data = {
> > .quirks = FLEXCAN_QUIRK_DISABLE_RXFG |
> FLEXCAN_QUIRK_ENABLE_EACEN_RRS |
> > FLEXCAN_QUIRK_USE_OFF_TIMESTAMP |
> FLEXCAN_QUIRK_BROKEN_PERR_STATE |
> > - FLEXCAN_QUIRK_SUPPORT_FD,
> > + FLEXCAN_QUIRK_SUPPORT_FD |
> FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW,
> > };
> >
> > static struct flexcan_devtype_data fsl_imx8mp_devtype_data = { @@
> > -546,18 +556,42 @@ static void flexcan_enable_wakeup_irq(struct
> flexcan_priv *priv, bool enable)
> > priv->write(reg_mcr, ®s->mcr);
> > }
> >
> > +static int flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv,
> > +bool enabled) {
> > + u8 idx = priv->can_idx;
> > + u32 rsrc_id, val;
> > +
> > + rsrc_id = FLEXCAN_IMX_SC_R_CAN(idx);
> > +
> > + if (enabled)
> > + val = 1;
> > + else
> > + val = 0;
> > +
> > + /* stop mode request via scu firmware */
> > + return imx_sc_misc_set_control(priv->sc_ipc_handle, rsrc_id,
> > + IMX_SC_C_IPG_STOP, val);
> > +}
> > +
> > static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
> > {
> > struct flexcan_regs __iomem *regs = priv->regs;
> > u32 reg_mcr;
> > + int ret;
> >
> > reg_mcr = priv->read(®s->mcr);
> > reg_mcr |= FLEXCAN_MCR_SLF_WAK;
> > priv->write(reg_mcr, ®s->mcr);
> >
> > /* enable stop request */
> > - regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
> > - 1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
> > + if (priv->devtype_data->quirks &
> FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
> > + ret = flexcan_stop_mode_enable_scfw(priv, true);
> > + if (ret < 0)
> > + return ret;
> > + } else {
> > + regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
> > + 1 << priv->stm.req_bit, 1 << priv->stm.req_bit);
> > + }
> >
> > return flexcan_low_power_enter_ack(priv);
> > }
> > @@ -566,10 +600,17 @@ static inline int flexcan_exit_stop_mode(struct
> > flexcan_priv *priv) {
> > struct flexcan_regs __iomem *regs = priv->regs;
> > u32 reg_mcr;
> > + int ret;
> >
> > /* remove stop request */
> > - regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
> > - 1 << priv->stm.req_bit, 0);
> > + if (priv->devtype_data->quirks &
> FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW) {
> > + ret = flexcan_stop_mode_enable_scfw(priv, false);
> > + if (ret < 0)
> > + return ret;
> > + } else {
> > + regmap_update_bits(priv->stm.gpr, priv->stm.req_gpr,
> > + 1 << priv->stm.req_bit, 0);
> > + }
> >
> > reg_mcr = priv->read(®s->mcr);
> > reg_mcr &= ~FLEXCAN_MCR_SLF_WAK;
> > @@ -1838,7 +1879,7 @@ static void unregister_flexcandev(struct
> net_device *dev)
> > unregister_candev(dev);
> > }
> >
> > -static int flexcan_setup_stop_mode(struct platform_device *pdev)
> > +static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
> > {
> > struct net_device *dev = platform_get_drvdata(pdev);
> > struct device_node *np = pdev->dev.of_node; @@ -1883,11 +1924,6 @@
> > static int flexcan_setup_stop_mode(struct platform_device *pdev)
> > "gpr %s req_gpr=0x02%x req_bit=%u\n",
> > gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
> >
> > - device_set_wakeup_capable(&pdev->dev, true);
> > -
> > - if (of_property_read_bool(np, "wakeup-source"))
> > - device_set_wakeup_enable(&pdev->dev, true);
> > -
> > return 0;
> >
> > out_put_node:
> > @@ -1895,6 +1931,64 @@ static int flexcan_setup_stop_mode(struct
> platform_device *pdev)
> > return ret;
> > }
> >
> > +static int flexcan_setup_stop_mode_scfw(struct platform_device *pdev)
> > +{
> > + struct net_device *dev = platform_get_drvdata(pdev);
> > + struct flexcan_priv *priv;
> > + u8 can_idx;
> > + int ret;
> > +
> > + ret = of_property_read_u8(pdev->dev.of_node, "fsl,scu-index", &can_idx);
> > + if (ret < 0) {
> > + dev_dbg(&pdev->dev, "failed to get scu index\n");
> > + return ret;
> > + }
> > +
> > + priv = netdev_priv(dev);
> > + priv->can_idx = can_idx;
> > +
> > + /* this function could be defered probe, return -EPROBE_DEFER */
> > + ret = imx_scu_get_handle(&priv->sc_ipc_handle);
> > + if (ret < 0) {
> > + dev_dbg(&pdev->dev, "get ipc handle used by SCU failed\n");
> > + return ret;
> > + }
>
> Don't print an error message on -EPROBE_DEFER.
Ok, make sense, thanks.
> > +
> > + return 0;
> > +}
> > +
> > +/* flexcan_setup_stop_mode - Setup stop mode for wakeup
> > + *
> > + * Return: = 0 setup stop mode successfully or doesn't support this feature
> > + * < 0 fail to setup stop mode (could be defered probe)
> > + */
> > +static int flexcan_setup_stop_mode(struct platform_device *pdev) {
> > + struct net_device *dev = platform_get_drvdata(pdev);
> > + struct flexcan_priv *priv;
> > + int ret;
> > +
> > + priv = netdev_priv(dev);
> > +
> > + if (priv->devtype_data->quirks &
> FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW)
> > + ret = flexcan_setup_stop_mode_scfw(pdev);
> > + else if (priv->devtype_data->quirks &
> FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR)
> > + ret = flexcan_setup_stop_mode_gpr(pdev);
> > + else
> > + /* return 0 directly if doesn't support stop mode feature */
> > + return 0;
> > +
> > + if (ret)
> > + return ret;
> > +
> > + device_set_wakeup_capable(&pdev->dev, true);
> > +
> > + if (of_property_read_bool(pdev->dev.of_node, "wakeup-source"))
> > + device_set_wakeup_enable(&pdev->dev, true);
> > +
> > + return 0;
> > +}
> > +
> > static const struct of_device_id flexcan_of_match[] = {
> > { .compatible = "fsl,imx8qm-flexcan", .data =
> &fsl_imx8qm_devtype_data, },
> > { .compatible = "fsl,imx8mp-flexcan", .data =
> > &fsl_imx8mp_devtype_data, }, @@ -2040,17 +2134,19 @@ static int
> flexcan_probe(struct platform_device *pdev)
> > goto failed_register;
> > }
> >
> > + err = flexcan_setup_stop_mode(pdev);
> > + if (err < 0) {
> > + dev_err(&pdev->dev, "setup stop mode failed\n");
> > + goto failed_canregister;
> > + }
> > +
> > of_can_transceiver(dev);
> > devm_can_led_init(dev);
> >
> > - if (priv->devtype_data->quirks &
> FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR) {
> > - err = flexcan_setup_stop_mode(pdev);
> > - if (err)
> > - dev_dbg(&pdev->dev, "failed to setup stop-mode\n");
> > - }
> > -
> > return 0;
> >
> > + failed_canregister:
> > + unregister_flexcandev(dev);
> > failed_register:
> > pm_runtime_put_noidle(&pdev->dev);
> > pm_runtime_disable(&pdev->dev);
> > @@ -2062,6 +2158,7 @@ static int flexcan_remove(struct platform_device
> > *pdev) {
> > struct net_device *dev = platform_get_drvdata(pdev);
> >
> > + device_set_wakeup_enable(&pdev->dev, false);
>
> Please make this a seperate patch, as it fixes a bug.
Ok.
Best Regards,
Joakim Zh
> > unregister_flexcandev(dev);
> > pm_runtime_disable(&pdev->dev);
> > free_candev(dev);
> >
> Marc
>
> --
> Pengutronix e.K. | Marc Kleine-Budde |
> Embedded Linux | https://www.pengutronix.de |
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