[U-Boot] [PATCH v3] rockchip: reserve memory for rk3399 ATF data

[Kever Yang]

There are 3 regions used by rk3399 ATF:
- bl31 code, located at 0x10000;
- cortex-m0 code and data, located at 0xff8c0000;
- bl31 data, located at 0xff8c1000 ~ 0xff8c4000;

SPL_TEXT_BASE starts from 0xff8c2000, we need to reserve memory
for ATF data, or else there will be memory corrupt after SPL
loads the ATF image.

More detail about cortex-M0 code in ATF:
https://github.com/ARM-software/arm-trusted-firmware/commit/
8382e17c4c6bffd15119dfce1ee4372e3c1a7890

Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
---

Changes in v3:
- grammar fix by Andreas's comment

Changes in v2:
- use Kconfig for the reserved memory size

 arch/arm/include/asm/arch-rockchip/boot0.h | 4 ++++
 arch/arm/mach-rockchip/Kconfig             | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/arch/arm/include/asm/arch-rockchip/boot0.h b/arch/arm/include/asm/arch-rockchip/boot0.h
index 8d7bc9a..7346876 100644
--- a/arch/arm/include/asm/arch-rockchip/boot0.h
+++ b/arch/arm/include/asm/arch-rockchip/boot0.h
@@ -16,3 +16,7 @@
 	.space 0x4         /* space for the 'RK33' */
 #endif
 	b reset
+
+#if defined(CONFIG_ROCKCHIP_RK3399) && defined(CONFIG_SPL_BUILD)
+	.space CONFIG_ROCKCHIP_SPL_RESERVE_IRAM	/* space for the ATF data */
+#endif
diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
index af0796d..da280f6 100644
--- a/arch/arm/mach-rockchip/Kconfig
+++ b/arch/arm/mach-rockchip/Kconfig
@@ -72,6 +72,14 @@ config ROCKCHIP_SPL_BACK_TO_BROM
           SPL will return to the boot rom, which will then load the U-Boot
           binary to keep going on.
 
+config ROCKCHIP_SPL_RESERVE_IRAM
+	hex "Size of IRAM reserved in SPL"
+	default 0x4000
+	help
+	  SPL may need reserve memory for firmware loaded by SPL, whose load
+	  address is in IRAM and may overlay with SPL text area if not
+	  reserved.
+
 config ROCKCHIP_BROM_HELPER
 	bool
 
-- 
1.9.1