[PATCH 03/27] imx: imx8ulp: Add M33 handshake functions

[Peng Fan (OSS)]

From: Ye Li <ye.li at nxp.com>

Add functions to check if M33 image is booted and handshake with M33
image via MU. A core notifies M33 to start init by FCR F0, then wait
M33 init done signal by checking FSR F0.

Reviewed-by: Peng Fan <peng.fan at nxp.com>
Signed-off-by: Ye Li <ye.li at nxp.com>
Signed-off-by: Biwen Li <biwen.li at nxp.com>
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 arch/arm/include/asm/arch-imx8ulp/imx-regs.h  |  1 +
 arch/arm/include/asm/arch-imx8ulp/sys_proto.h |  2 ++
 arch/arm/mach-imx/imx8ulp/soc.c               | 36 +++++++++++++++++++
 3 files changed, 39 insertions(+)

diff --git a/arch/arm/include/asm/arch-imx8ulp/imx-regs.h b/arch/arm/include/asm/arch-imx8ulp/imx-regs.h
index 91adc85525..723bab584c 100644
--- a/arch/arm/include/asm/arch-imx8ulp/imx-regs.h
+++ b/arch/arm/include/asm/arch-imx8ulp/imx-regs.h
@@ -14,6 +14,7 @@
 
 #define CMC0_RBASE		0x28025000
 
+#define MU0_B_BASE_ADDR		0x29220000
 #define CMC1_BASE_ADDR		0x29240000
 
 #define SIM1_BASE_ADDR		0x29290000
diff --git a/arch/arm/include/asm/arch-imx8ulp/sys_proto.h b/arch/arm/include/asm/arch-imx8ulp/sys_proto.h
index 284ccafc98..5f030eaa0a 100644
--- a/arch/arm/include/asm/arch-imx8ulp/sys_proto.h
+++ b/arch/arm/include/asm/arch-imx8ulp/sys_proto.h
@@ -18,4 +18,6 @@ int xrdc_config_pdac_openacc(u32 bridge, u32 index);
 enum boot_device get_boot_device(void);
 void set_lpav_qos(void);
 void load_lposc_fuse(void);
+bool m33_image_booted(void);
+int m33_image_handshake(ulong timeout_ms);
 #endif
diff --git a/arch/arm/mach-imx/imx8ulp/soc.c b/arch/arm/mach-imx/imx8ulp/soc.c
index 934b0ef038..b9c146fc26 100644
--- a/arch/arm/mach-imx/imx8ulp/soc.c
+++ b/arch/arm/mach-imx/imx8ulp/soc.c
@@ -25,6 +25,7 @@
 #include <dm/uclass-internal.h>
 #include <fuse.h>
 #include <thermal.h>
+#include <linux/iopoll.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -136,6 +137,41 @@ enum bt_mode get_boot_mode(void)
 	return LOW_POWER_BOOT;
 }
 
+bool m33_image_booted(void)
+{
+	u32 gp6;
+
+	/* DGO_GP6 */
+	gp6 = readl(SIM_SEC_BASE_ADDR + 0x28);
+	if (gp6 & BIT(5))
+		return true;
+
+	return false;
+}
+
+int m33_image_handshake(ulong timeout_ms)
+{
+	u32 fsr;
+	int ret;
+	ulong timeout_us = timeout_ms * 1000;
+
+	/* enable MU0_MUB clock before access the register of MU0_MUB */
+	pcc_clock_enable(3, MU0_B_PCC3_SLOT, true);
+
+	/* Notify m33 that it's ready to do init srtm(enable mu receive interrupt and so on) */
+	setbits_le32(MU0_B_BASE_ADDR + 0x100, BIT(0)); /* set FCR F0 flag of MU0_MUB */
+
+	/*
+	 * Wait m33 to set FCR F0 flag of MU0_MUA
+	 * Clear FCR F0 flag of MU0_MUB after m33 has set FCR F0 flag of MU0_MUA
+	 */
+	ret = readl_poll_sleep_timeout(MU0_B_BASE_ADDR + 0x104, fsr, fsr & BIT(0), 10, timeout_us);
+	if (!ret)
+		clrbits_le32(MU0_B_BASE_ADDR + 0x100, BIT(0));
+
+	return ret;
+}
+
 #define CMC_SRS_TAMPER                    BIT(31)
 #define CMC_SRS_SECURITY                  BIT(30)
 #define CMC_SRS_TZWDG                     BIT(29)
-- 
2.30.0