On 9/25/20 5:10 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.MX8, stop mode request is controlled by System Controller Unit(SCU)
> firmware.
As you mentioned in the other mail, some functions are missing from the
>
> Signed-off-by: Joakim Zhang <qiangqing.zhang@xxxxxxx>
> ---
> drivers/net/can/flexcan.c | 81 ++++++++++++++++++++++++++++++++-------
> 1 file changed, 68 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c
> index 8c8753f77764..41b52cb56f93 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>
> @@ -240,6 +242,8 @@
> #define FLEXCAN_QUIRK_SETUP_STOP_MODE BIT(8)
rename this into "FLEXCAN_QUIRK_SETUP_STOP_MODE_GPR"
> /* Support CAN-FD mode */
> #define FLEXCAN_QUIRK_SUPPORT_FD BIT(9)
> +/* Use System Controller Firmware */
> +#define FLEXCAN_QUIRK_USE_SCFW BIT(10)
...and this into FLEXCAN_QUIRK_SETUP_STOP_MODE_SCFW
>
> /* Structure of the message buffer */
> struct flexcan_mb {
> @@ -358,6 +362,9 @@ struct flexcan_priv {
> struct regulator *reg_xceiver;
> struct flexcan_stop_mode stm;
>
> + /* IPC handle when enable 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 +394,8 @@ 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 |
> + FLEXCAN_QUIRK_USE_SCFW,
> };
>
> static struct flexcan_devtype_data fsl_imx8mp_devtype_data = {
> @@ -546,6 +554,25 @@ static void flexcan_enable_wakeup_irq(struct flexcan_priv *priv, bool enable)
> priv->write(reg_mcr, ®s->mcr);
> }
>
> +static void flexcan_stop_mode_enable_scfw(struct flexcan_priv *priv, bool enabled)
> +{
> + struct device_node *np = priv->dev->of_node;
> + u32 rsrc_id, val;
> + int idx;
> +
> + idx = of_alias_get_id(np, "can");
> + if (idx == 0)
> + rsrc_id = IMX_SC_R_CAN_0;
> + else if (idx == 1)
> + rsrc_id = IMX_SC_R_CAN_1;
> + else
> + rsrc_id = IMX_SC_R_CAN_2;
This looks too fragile to me. Better add a property to the DT which indicates
the index.
> +
> + val = enabled ? 1 : 0;
Please use an if() here.
> + /* stop mode request */
> + 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;
> @@ -555,9 +582,12 @@ static inline int flexcan_enter_stop_mode(struct flexcan_priv *priv)
> 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);
> + /* enable stop request */
> + if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_SCFW)
> + flexcan_stop_mode_enable_scfw(priv, true);
error handling?
> + 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);
> }
> @@ -568,8 +598,11 @@ static inline int flexcan_exit_stop_mode(struct flexcan_priv *priv)
> u32 reg_mcr;
>
> /* 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_USE_SCFW)
> + flexcan_stop_mode_enable_scfw(priv, false);
error handling?
> + 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;
> @@ -1927,11 +1960,6 @@ static int flexcan_setup_stop_mode(struct platform_device *pdev)
> gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit,
> priv->stm.ack_gpr, priv->stm.ack_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:
> @@ -1939,6 +1967,23 @@ 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;
> + int ret;
> +
> + priv = netdev_priv(dev);
> +
> + ret = imx_scu_get_handle(&priv->sc_ipc_handle);
this function can return -EPROBE_DEFER
https://elixir.bootlin.com/linux/latest/source/drivers/firmware/imx/imx-scu.c#L97
> + if (ret < 0) {
> + dev_err(&pdev->dev, "get ipc handle used by SCU failed\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> static const struct of_device_id flexcan_of_match[] = {
> { .compatible = "fsl,imx8mp-flexcan", .data = &fsl_imx8mp_devtype_data, },
> { .compatible = "fsl,imx8qm-flexcan", .data = &fsl_imx8qm_devtype_data, },
> @@ -2088,9 +2133,19 @@ static int flexcan_probe(struct platform_device *pdev)
> devm_can_led_init(dev);
>
> if (priv->devtype_data->quirks & FLEXCAN_QUIRK_SETUP_STOP_MODE) {
> - err = flexcan_setup_stop_mode(pdev);
what about renaming the flexcan_setup_stop_mode() to
flexcan_setup_stop_mode_gpr() and moving this below into a function called
flexcan_setup_stop_mode().
> - if (err)
> + if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_SCFW)
> + err = flexcan_setup_stop_mode_scfw(pdev);
> + else
> + err = flexcan_setup_stop_mode(pdev);
> +
> + if (err) {
> dev_dbg(&pdev->dev, "failed to setup stop-mode\n");
> + } else {
> + 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;
>
Marc
--
Pengutronix e.K. | Marc Kleine-Budde |
Embedded Linux | https://www.pengutronix.de |
Vertretung West/Dortmund | Phone: +49-231-2826-924 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
Attachment:
signature.asc
Description: OpenPGP digital signature
