[PATCH v6 6/7] arm: Get bloblist from boot arguments

[Raymond Mao]

Add arch custom function to get bloblist from boot arguments.
Check whether boot arguments aligns with the register conventions
defined in FW Handoff spec v0.9.
Add bloblist related options into qemu-arm default config.
Remove OF_HAS_PRIOR_STAGE and OF_BOARD from qemu-arm config.

Signed-off-by: Raymond Mao <raymond.mao at linaro.org>
---
Changes in v2
- Remove low level code for copying boot arguments.
- Refactor board_fdt_blob_setup() and remove direct access of gd->bloblist.
Changes in v3
- Optimize board_bloblist_from_boot_arg().
Changes in v4
- Move the function as an Arm-arch library instead of a board-specific one.
Changes in V5
- Drop the dependence on OF_BOARD.
- Move external declaration to header file.
- Adjust the position of BLOBLIST in defconfig file.
Changes in V6
- Drop imply OF_HAS_PRIOR_STAGE from qemu-arm.

 arch/arm/Kconfig             |  1 -
 arch/arm/lib/Makefile        |  2 ++
 arch/arm/lib/xferlist.c      | 27 +++++++++++++++++++++++++++
 arch/arm/lib/xferlist.h      | 19 +++++++++++++++++++
 configs/qemu_arm64_defconfig |  3 +++
 5 files changed, 51 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/lib/xferlist.c
 create mode 100644 arch/arm/lib/xferlist.h

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 2d4458b7b5..745b68f20f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1047,7 +1047,6 @@ config ARCH_QEMU
 	imply DM_RNG
 	imply DM_RTC
 	imply RTC_PL031
-	imply OF_HAS_PRIOR_STAGE
 	imply VIDEO
 	imply VIDEO_BOCHS
 	imply SYS_WHITE_ON_BLACK
diff --git a/arch/arm/lib/Makefile b/arch/arm/lib/Makefile
index b1bcd37466..67275fba61 100644
--- a/arch/arm/lib/Makefile
+++ b/arch/arm/lib/Makefile
@@ -85,6 +85,8 @@ obj-y	+= psci-dt.o
 
 obj-$(CONFIG_DEBUG_LL)	+= debug.o
 
+obj-$(CONFIG_BLOBLIST)  += xferlist.o
+
 # For EABI conformant tool chains, provide eabi_compat()
 ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
 extra-y	+= eabi_compat.o
diff --git a/arch/arm/lib/xferlist.c b/arch/arm/lib/xferlist.c
new file mode 100644
index 0000000000..e9734959dc
--- /dev/null
+++ b/arch/arm/lib/xferlist.c
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2023 Linaro Limited
+ * Author: Raymond Mao <raymond.mao at linaro.org>
+ */
+#include <linux/types.h>
+#include <errno.h>
+#include <bloblist.h>
+#include "xferlist.h"
+
+int xferlist_from_boot_arg(ulong addr, ulong size)
+{
+	int ret;
+
+	ret = bloblist_check(saved_args[3], size);
+	if (ret)
+		return ret;
+
+	/* Check the register conventions */
+	ret = bloblist_check_reg_conv(saved_args[0], saved_args[2],
+				      saved_args[1]);
+	if (!ret)
+		/* Relocate the bloblist to the fixed address */
+		ret = bloblist_reloc((void *)addr, size);
+
+	return ret;
+}
diff --git a/arch/arm/lib/xferlist.h b/arch/arm/lib/xferlist.h
new file mode 100644
index 0000000000..60d79c1a8e
--- /dev/null
+++ b/arch/arm/lib/xferlist.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0+ BSD-3-Clause */
+/*
+ * Copyright (C) 2023 Linaro Limited
+ * Author: Raymond Mao <raymond.mao at linaro.org>
+ */
+
+#ifndef _XFERLIST_H_
+#define _XFERLIST_H_
+
+/*
+ * Boot parameters saved from start.S
+ * saved_args[0]: FDT base address
+ * saved_args[1]: Bloblist signature
+ * saved_args[2]: must be 0
+ * saved_args[3]: Bloblist base address
+ */
+extern unsigned long saved_args[];
+
+#endif /* _XFERLIST_H_ */
diff --git a/configs/qemu_arm64_defconfig b/configs/qemu_arm64_defconfig
index 5100e193be..80a5409c51 100644
--- a/configs/qemu_arm64_defconfig
+++ b/configs/qemu_arm64_defconfig
@@ -27,6 +27,9 @@ CONFIG_USE_PREBOOT=y
 # CONFIG_DISPLAY_CPUINFO is not set
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_PCI_INIT_R=y
+CONFIG_BLOBLIST=y
+CONFIG_BLOBLIST_ADDR=0x40004000
+CONFIG_BLOBLIST_SIZE=0x4000
 CONFIG_CMD_BOOTZ=y
 CONFIG_CMD_BOOTEFI_SELFTEST=y
 CONFIG_CMD_NVEDIT_EFI=y
-- 
2.25.1