[v6 07/18] arm: socfpga: Add secure register access helper functions for SoC 64bits

[Siew Chin Lim]

These secure register access functions allow U-Boot proper running
at EL2 (non-secure) to access System Manager's secure registers
by calling the ATF's PSCI runtime services (EL3/secure).

Signed-off-by: Siew Chin Lim <elly.siew.chin.lim at intel.com>

---
v5
---
Return error code instead of hang the system if fail to access
the secure register.

---
v6
---
Directly return 'ret' after SMC call in write and update function.
---
 arch/arm/mach-socfpga/Makefile                     |  1 +
 .../mach-socfpga/include/mach/secure_reg_helper.h  | 19 +++++
 arch/arm/mach-socfpga/secure_reg_helper.c          | 91 ++++++++++++++++++++++
 3 files changed, 111 insertions(+)
 create mode 100644 arch/arm/mach-socfpga/include/mach/secure_reg_helper.h
 create mode 100644 arch/arm/mach-socfpga/secure_reg_helper.c

diff --git a/arch/arm/mach-socfpga/Makefile b/arch/arm/mach-socfpga/Makefile
index 0b05283a7a..82b681d870 100644
--- a/arch/arm/mach-socfpga/Makefile
+++ b/arch/arm/mach-socfpga/Makefile
@@ -73,6 +73,7 @@ obj-y	+= firewall.o
 obj-y	+= spl_agilex.o
 endif
 else
+obj-$(CONFIG_SPL_ATF) += secure_reg_helper.o
 obj-$(CONFIG_SPL_ATF) += smc_api.o
 endif
 
diff --git a/arch/arm/mach-socfpga/include/mach/secure_reg_helper.h b/arch/arm/mach-socfpga/include/mach/secure_reg_helper.h
new file mode 100644
index 0000000000..d5a11122c7
--- /dev/null
+++ b/arch/arm/mach-socfpga/include/mach/secure_reg_helper.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2020 Intel Corporation <www.intel.com>
+ *
+ */
+
+#ifndef	_SECURE_REG_HELPER_H_
+#define	_SECURE_REG_HELPER_H_
+
+#define SOCFPGA_SECURE_REG_SYSMGR_SOC64_SDMMC 1
+#define SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC0 2
+#define SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC1 3
+#define SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC2 4
+
+int socfpga_secure_reg_read32(u32 id, u32 *val);
+int socfpga_secure_reg_write32(u32 id, u32 val);
+int socfpga_secure_reg_update32(u32 id, u32 mask, u32 val);
+
+#endif /* _SECURE_REG_HELPER_H_ */
diff --git a/arch/arm/mach-socfpga/secure_reg_helper.c b/arch/arm/mach-socfpga/secure_reg_helper.c
new file mode 100644
index 0000000000..816006cb5a
--- /dev/null
+++ b/arch/arm/mach-socfpga/secure_reg_helper.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2020 Intel Corporation <www.intel.com>
+ *
+ */
+
+#include <common.h>
+#include <hang.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/arch/misc.h>
+#include <asm/arch/secure_reg_helper.h>
+#include <asm/arch/smc_api.h>
+#include <asm/arch/system_manager.h>
+#include <linux/errno.h>
+#include <linux/intel-smc.h>
+
+int socfpga_secure_convert_reg_id_to_addr(u32 id, phys_addr_t *reg_addr)
+{
+	switch (id) {
+	case SOCFPGA_SECURE_REG_SYSMGR_SOC64_SDMMC:
+		*reg_addr = socfpga_get_sysmgr_addr() + SYSMGR_SOC64_SDMMC;
+		break;
+	case SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC0:
+		*reg_addr = socfpga_get_sysmgr_addr() + SYSMGR_SOC64_EMAC0;
+		break;
+	case SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC1:
+		*reg_addr = socfpga_get_sysmgr_addr() + SYSMGR_SOC64_EMAC1;
+		break;
+	case SOCFPGA_SECURE_REG_SYSMGR_SOC64_EMAC2:
+		*reg_addr = socfpga_get_sysmgr_addr() + SYSMGR_SOC64_EMAC2;
+		break;
+	default:
+		return -EADDRNOTAVAIL;
+	}
+	return 0;
+}
+
+int socfpga_secure_reg_read32(u32 id, u32 *val)
+{
+	int ret;
+	u64 ret_arg;
+	u64 args[1];
+
+	phys_addr_t reg_addr;
+	ret = socfpga_secure_convert_reg_id_to_addr(id, &reg_addr);
+	if (ret)
+		return ret;
+
+	args[0] = (u64)reg_addr;
+	ret = invoke_smc(INTEL_SIP_SMC_REG_READ, args, 1, &ret_arg, 1);
+	if (ret)
+		return ret;
+
+	*val = (u32)ret_arg;
+
+	return 0;
+}
+
+int socfpga_secure_reg_write32(u32 id, u32 val)
+{
+	int ret;
+	u64 args[2];
+
+	phys_addr_t reg_addr;
+	ret = socfpga_secure_convert_reg_id_to_addr(id, &reg_addr);
+	if (ret)
+		return ret;
+
+	args[0] = (u64)reg_addr;
+	args[1] = val;
+	ret = invoke_smc(INTEL_SIP_SMC_REG_WRITE, args, 2, NULL, 0);
+	return ret;
+}
+
+int socfpga_secure_reg_update32(u32 id, u32 mask, u32 val)
+{
+	int ret;
+	u64 args[3];
+
+	phys_addr_t reg_addr;
+	ret = socfpga_secure_convert_reg_id_to_addr(id, &reg_addr);
+	if (ret)
+		return ret;
+
+	args[0] = (u64)reg_addr;
+	args[1] = mask;
+	args[2] = val;
+	ret = invoke_smc(INTEL_SIP_SMC_REG_UPDATE, args, 3, NULL, 0);
+	return ret;
+}
-- 
2.13.0