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

From: Daniel Baluta
Date: Wed Jan 30 2019 - 08:30:28 EST


This is done via RPC call to SCU.

Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxx>
---
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