openwrtv3/target/linux/ipq806x/patches-3.18/300-arch-arm-force-ZRELADDR-on-arch-qcom.patch
Felix Fietkau bdcba36442 ipq806x: fix boot freeze on zImage kernel
ARCH_QCOM is using the ARCH_MULTIPLATFORM option, as now recommended
on most ARM architectures. This automatically calculate ZRELADDR by
masking PHYS_OFFSET with 0xf8000000.

On IPQ806x though, the first ~20MB of RAM is reserved for the hardware.
In newer bootloader, when DT is used, this is not a problem, we just
reserve this memory in the device tree. But if the bootloader doesn't
have DT support, then ATAGS have to be used. In this case, the ARM
decompressor will position the kernel in this low mem, which will not be
in the RAM section mapped by the bootloader, which means the kernel will
freeze in the middle of the boot process trying to map the memory.

As a work around, this patch allows disabling AUTO_ZRELADDR when
ARCH_QCOM is selected. It makes the zImage usage possible on bootloaders
which don't support device-tree, which is the case on certain early
IPQ806x based designs.

Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>

SVN-Revision: 45661
2015-05-10 11:46:56 +00:00

72 lines
2.5 KiB
Diff

From b12e230f09d4481424e6a5d7e2ae566b6954e83f Mon Sep 17 00:00:00 2001
From: Mathieu Olivari <mathieu@codeaurora.org>
Date: Wed, 29 Apr 2015 15:21:46 -0700
Subject: [PATCH] HACK: arch: arm: force ZRELADDR on arch-qcom
ARCH_QCOM is using the ARCH_MULTIPLATFORM option, as now recommended
on most ARM architectures. This automatically calculate ZRELADDR by
masking PHYS_OFFSET with 0xf8000000.
However, on IPQ806x, the first ~20MB of RAM is reserved for the hardware
network accelerators, and the bootloader removes this section from the
layout passed from the ATAGS (when used).
For newer bootloader, when DT is used, this is not a problem, we just
reserve this memory in the device tree. But if the bootloader doesn't
have DT support, then ATAGS have to be used. In this case, the ARM
decompressor will position the kernel in this low mem, which will not be
in the RAM section mapped by the bootloader, which means the kernel will
freeze in the middle of the boot process trying to map the memory.
As a work around, this patch allows disabling AUTO_ZRELADDR when
ARCH_QCOM is selected. It makes the zImage usage possible on bootloaders
which don't support device-tree, which is the case on certain early
IPQ806x based designs.
Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org>
---
arch/arm/Kconfig | 2 +-
arch/arm/Makefile | 2 ++
arch/arm/mach-qcom/Makefile.boot | 1 +
3 files changed, 4 insertions(+), 1 deletion(-)
create mode 100644 arch/arm/mach-qcom/Makefile.boot
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 89c4b5c..4583ea5 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -311,7 +311,7 @@ config ARCH_MULTIPLATFORM
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARM_HAS_SG_CHAIN
select ARM_PATCH_PHYS_VIRT
- select AUTO_ZRELADDR
+ select AUTO_ZRELADDR if !ARCH_QCOM
select CLKSRC_OF
select COMMON_CLK
select GENERIC_CLOCKEVENTS
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 7453352..5d6f8ac 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -240,9 +240,11 @@ MACHINE := arch/arm/mach-$(word 1,$(machine-y))/
else
MACHINE :=
endif
+ifeq ($(CONFIG_ARCH_QCOM),)
ifeq ($(CONFIG_ARCH_MULTIPLATFORM),y)
MACHINE :=
endif
+endif
machdirs := $(patsubst %,arch/arm/mach-%/,$(machine-y))
platdirs := $(patsubst %,arch/arm/plat-%/,$(sort $(plat-y)))
diff --git a/arch/arm/mach-qcom/Makefile.boot b/arch/arm/mach-qcom/Makefile.boot
new file mode 100644
index 0000000..67a6d5a
--- /dev/null
+++ b/arch/arm/mach-qcom/Makefile.boot
@@ -0,0 +1 @@
+zreladdr-y+= 0x42208000
--
1.9.1