RE: [PATCH v3] firmware: imx: Add support to start/stop a CPU

From: Aisheng Dong
Date: Thu Jan 31 2019 - 03:17:00 EST


> -----Original Message-----
> From: Daniel Baluta
> Sent: Wednesday, January 30, 2019 9:30 PM
> To: shawnguo@xxxxxxxxxx
> Cc: s.hauer@xxxxxxxxxxxxxx; kernel@xxxxxxxxxxxxxx; festevam@xxxxxxxxx;
> dl-linux-imx <linux-imx@xxxxxxx>; daniel.baluta@xxxxxxxxx; Aisheng Dong
> <aisheng.dong@xxxxxxx>; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; S.j. Wang <shengjiu.wang@xxxxxxx>; Daniel
> Baluta <daniel.baluta@xxxxxxx>
> Subject: [PATCH v3] firmware: imx: Add support to start/stop a CPU
>
> This is done via RPC call to SCU.
>
> Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>

Reviewed-by: Dong Aisheng <aisheng.dong@xxxxxxx>

Regards
Dong Aisheng

> ---
> Changes since v2: (as per Aisheng's review)
> - rename address with phys_address
> - remove unnecessary uint8_t cast
> - use 'true' as last parameter of imx_scu_call_rpc to actually
> wait for a response from SCU.
>
> drivers/firmware/imx/misc.c | 38
> +++++++++++++++++++++++++++
> include/linux/firmware/imx/svc/misc.h | 3 +++
> 2 files changed, 41 insertions(+)
>
> diff --git a/drivers/firmware/imx/misc.c b/drivers/firmware/imx/misc.c index
> 97f5424dbac9..4b56a587dacd 100644
> --- a/drivers/firmware/imx/misc.c
> +++ b/drivers/firmware/imx/misc.c
> @@ -18,6 +18,14 @@ struct imx_sc_msg_req_misc_set_ctrl {
> u16 resource;
> } __packed;
>
> +struct imx_sc_msg_req_cpu_start {
> + struct imx_sc_rpc_msg hdr;
> + u32 address_hi;
> + u32 address_lo;
> + u16 resource;
> + u8 enable;
> +} __packed;
> +
> struct imx_sc_msg_req_misc_get_ctrl {
> struct imx_sc_rpc_msg hdr;
> u32 ctrl;
> @@ -97,3 +105,33 @@ int imx_sc_misc_get_control(struct imx_sc_ipc *ipc,
> u32 resource,
> return 0;
> }
> EXPORT_SYMBOL(imx_sc_misc_get_control);
> +
> +/*
> + * This function starts/stops a CPU identified by @resource
> + *
> + * @param[in] ipc IPC handle
> + * @param[in] resource resource the control is associated with
> + * @param[in] enable true for start, false for stop
> + * @param[in] phys_addr initial instruction address to be executed
> + *
> + * @return Returns 0 for success and < 0 for errors.
> + */
> +int imx_sc_pm_cpu_start(struct imx_sc_ipc *ipc, u32 resource,
> + bool enable, u64 phys_addr)
> +{
> + struct imx_sc_msg_req_cpu_start msg;
> + struct imx_sc_rpc_msg *hdr = &msg.hdr;
> +
> + hdr->ver = IMX_SC_RPC_VERSION;
> + hdr->svc = IMX_SC_RPC_SVC_PM;
> + hdr->func = IMX_SC_PM_FUNC_CPU_START;
> + hdr->size = 4;
> +
> + msg.address_hi = phys_addr >> 32;
> + msg.address_lo = phys_addr;
> + msg.resource = resource;
> + msg.enable = enable;
> +
> + return imx_scu_call_rpc(ipc, &msg, true); }
> +EXPORT_SYMBOL(imx_sc_pm_cpu_start);
> diff --git a/include/linux/firmware/imx/svc/misc.h
> b/include/linux/firmware/imx/svc/misc.h
> index e21c49aba92f..031dd4d3c766 100644
> --- a/include/linux/firmware/imx/svc/misc.h
> +++ b/include/linux/firmware/imx/svc/misc.h
> @@ -52,4 +52,7 @@ int imx_sc_misc_set_control(struct imx_sc_ipc *ipc, u32
> resource, int imx_sc_misc_get_control(struct imx_sc_ipc *ipc, u32 resource,
> u8 ctrl, u32 *val);
>
> +int imx_sc_pm_cpu_start(struct imx_sc_ipc *ipc, u32 resource,
> + bool enable, u64 phys_addr);
> +
> #endif /* _SC_MISC_API_H */
> --
> 2.17.1