[UBOOT PATCH] xilinx: versal: Add firmware access to CRP Boot mode register

[Venkatesh Yadav Abbarapu]

From: Prasad Kummari <prasad.kummari at amd.com>

Added extended support for retrieving the boot mode register
via the firmware interface, which is preferred when U-Boot
runs in EL2 and cannot directly access CRP registers via raw
reads. Ideally, all secure registers should be accessed via
xilinx_pm_request(). Introduced the secure zynqmp_pm_get_bootmode_reg()
call, which uses xilinx_pm_request() to read the boot mode register.

When CONFIG_ZYNQMP_FIRMWARE is enabled, the secure
zynqmp_pm_get_bootmode_reg() call is used; otherwise,
direct raw reads are performed in the case of mini U-Boot.

Signed-off-by: Prasad Kummari <prasad.kummari at amd.com>
Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu at amd.com>
---
 board/xilinx/versal-net/board.c    |  7 ++++++-
 board/xilinx/versal/board.c        |  7 ++++++-
 drivers/firmware/firmware-zynqmp.c | 23 +++++++++++++++++++++++
 include/zynqmp_firmware.h          |  4 ++++
 4 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/board/xilinx/versal-net/board.c b/board/xilinx/versal-net/board.c
index 4d5913cff1d..f8ac54e35a8 100644
--- a/board/xilinx/versal-net/board.c
+++ b/board/xilinx/versal-net/board.c
@@ -21,6 +21,7 @@
 #include <asm/arch/sys_proto.h>
 #include <dm/device.h>
 #include <dm/uclass.h>
+#include <zynqmp_firmware.h>
 #include "../common/board.h"
 
 #include <linux/bitfield.h>
@@ -184,7 +185,11 @@ static u8 versal_net_get_bootmode(void)
 	u8 bootmode;
 	u32 reg = 0;
 
-	reg = readl(&crp_base->boot_mode_usr);
+	if (IS_ENABLED(CONFIG_ZYNQMP_FIRMWARE) && current_el() != 3) {
+		reg = zynqmp_pm_get_bootmode_reg();
+	} else {
+		reg = readl(&crp_base->boot_mode_usr);
+	}
 
 	if (reg >> BOOT_MODE_ALT_SHIFT)
 		reg >>= BOOT_MODE_ALT_SHIFT;
diff --git a/board/xilinx/versal/board.c b/board/xilinx/versal/board.c
index b4483d00ad1..3046fd7e5f0 100644
--- a/board/xilinx/versal/board.c
+++ b/board/xilinx/versal/board.c
@@ -26,6 +26,7 @@
 #include <dm/device.h>
 #include <dm/uclass.h>
 #include <versalpl.h>
+#include <zynqmp_firmware.h>
 #include "../common/board.h"
 
 DECLARE_GLOBAL_DATA_PTR;
@@ -42,7 +43,11 @@ static u8 versal_get_bootmode(void)
 	u8 bootmode;
 	u32 reg = 0;
 
-	reg = readl(&crp_base->boot_mode_usr);
+	if (IS_ENABLED(CONFIG_ZYNQMP_FIRMWARE) && current_el() != 3) {
+		reg = zynqmp_pm_get_bootmode_reg();
+	} else {
+		reg = readl(&crp_base->boot_mode_usr);
+	}
 
 	if (reg >> BOOT_MODE_ALT_SHIFT)
 		reg >>= BOOT_MODE_ALT_SHIFT;
diff --git a/drivers/firmware/firmware-zynqmp.c b/drivers/firmware/firmware-zynqmp.c
index 4b1b80d7abe..2adc132b4cc 100644
--- a/drivers/firmware/firmware-zynqmp.c
+++ b/drivers/firmware/firmware-zynqmp.c
@@ -195,6 +195,29 @@ int zynqmp_pm_set_sd_config(u32 node, enum pm_sd_config_type config, u32 value)
 	return ret;
 }
 
+u32 zynqmp_pm_get_bootmode_reg(void)
+{
+	int ret;
+	u32 ret_payload[PAYLOAD_ARG_CNT];
+
+	ret = zynqmp_pm_is_function_supported(PM_IOCTL, IOCTL_READ_REG);
+	if (ret) {
+		printf("%s: IOCTL_READ_REG is not supported failed with error code: %d\n"
+		       , __func__, ret);
+		return 0;
+	}
+
+	ret = xilinx_pm_request(PM_IOCTL, CRP_BOOT_MODE_REG_NODE, IOCTL_READ_REG,
+				CRP_BOOT_MODE_REG_OFFSET, 0, ret_payload);
+	if (ret) {
+		printf("%s: node 0x%x: get_bootmode 0x%x failed\n",
+		       __func__, CRP_BOOT_MODE_REG_NODE, CRP_BOOT_MODE_REG_OFFSET);
+		return 0;
+	}
+
+	return ret_payload[1];
+}
+
 int zynqmp_pm_feature(const u32 api_id)
 {
 	int ret;
diff --git a/include/zynqmp_firmware.h b/include/zynqmp_firmware.h
index 73198a6a6ea..e7275f72fac 100644
--- a/include/zynqmp_firmware.h
+++ b/include/zynqmp_firmware.h
@@ -457,6 +457,7 @@ int zynqmp_pm_is_function_supported(const u32 api_id, const u32 id);
 int zynqmp_mmio_read(const u32 address, u32 *value);
 int zynqmp_mmio_write(const u32 address, const u32 mask, const u32 value);
 int zynqmp_pm_feature(const u32 api_id);
+u32 zynqmp_pm_get_bootmode_reg(void);
 
 /* Type of Config Object */
 #define PM_CONFIG_OBJECT_TYPE_BASE	0x1U
@@ -500,4 +501,7 @@ struct zynqmp_ipi_msg {
 	u32 *buf;
 };
 
+#define CRP_BOOT_MODE_REG_NODE		0x30000001
+#define CRP_BOOT_MODE_REG_OFFSET	0x200
+
 #endif /* _ZYNQMP_FIRMWARE_H_ */
-- 
2.25.1