[PATCH 4/5] [ARM] Auto calculate ZRELADDR and provide option for exceptions

Thu Jun 3 03:36:52 EDT 2010

From: Eric Miao <eric.y.miao at gmail.com>

Original idea and prototype came from Nicolas Pitre.

As long as the zImage is placed within the 256MB range from the
start of the memory, ZRELADDR (Address where the decompressed
kernel will be placed, usually  == PHYS_OFFSET + TEXT_OFFSET)
can be determined at run-time by masking PC with 0xf000_0000.

Running through all the Makefile.boot, all those zreladdr-y
address == 0x[0-f]000_0000 + TEXT_OFFSET can be determined at
run-time.

Option CONFIG_AUTO_ZRELADDR and CONFIG_ZRELADDR are introduced,
CONFIG_ZRELADDR _must_ be explicitly specified if:

 - ((zreladdr-y - TEXT_OFFSET) & ~0xf0000000) != 0, which means
   a maksing of PC with 0xf000_0000 will result an incorrect
   address.

 - or the assumption of the zImage being loaded by the boot
   loader within 256MB from the start address is simply
   incorrect

 - or when ZBOOT_ROM is used, where the above assumption is
   normally wrong

List of all Makefile.boot:

Hardcoded, and can be auto calculated by masking PC with 0xf000_0000:

arch/arm/mach-cns3xxx/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-dove/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ebsa110/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-footbridge/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-integrator/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-iop13xx/Makefile.boot:	   zreladdr-y   := 0x00008000
arch/arm/mach-iop33x/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ixp2000/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ixp23xx/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ixp4xx/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-kirkwood/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ks8695/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-loki/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-mmp/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-mv78xx0/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-nomadik/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-nuc93x/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-ns9xxx/Makefile.boot:	   zreladdr-y	:= 0x8000
arch/arm/mach-orion5x/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-spear3xx/Makefile.boot:      zreladdr-y	:= 0x00008000
arch/arm/mach-spear6xx/Makefile.boot:      zreladdr-y	:= 0x00008000
arch/arm/mach-ux500/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-versatile/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-w90x900/Makefile.boot:	   zreladdr-y	:= 0x00008000
arch/arm/mach-msm/Makefile.boot:	   zreladdr-y	:= 0x10008000
arch/arm/mach-omap1/Makefile.boot:	   zreladdr-y	:= 0x10008000
arch/arm/mach-rpc/Makefile.boot:	   zreladdr-y	:= 0x10008000
arch/arm/mach-s5p6440/Makefile.boot:	   zreladdr-y	:= 0x20008000
arch/arm/mach-s5p6442/Makefile.boot:	   zreladdr-y	:= 0x20008000
arch/arm/mach-s5pc100/Makefile.boot:	   zreladdr-y	:= 0x20008000
arch/arm/mach-s5pv210/Makefile.boot:	   zreladdr-y	:= 0x20008000
arch/arm/mach-s3c2410/Makefile.boot:	   zreladdr-y	:= 0x30008000
arch/arm/mach-s3c2410/Makefile.boot:	   zreladdr-y	:= 0x30108000
arch/arm/mach-stmp378x/Makefile.boot:	   zreladdr-y	:= 0x40008000
arch/arm/mach-stmp37xx/Makefile.boot:	   zreladdr-y	:= 0x40008000
arch/arm/mach-s3c64xx/Makefile.boot:	   zreladdr-y	:= 0x50008000
arch/arm/mach-vexpress/Makefile.boot:	   zreladdr-y	:= 0x60008000
arch/arm/mach-mx25/Makefile.boot:	   zreladdr-y	:= 0x80008000
arch/arm/mach-mx3/Makefile.boot:	   zreladdr-y	:= 0x80008000
arch/arm/mach-netx/Makefile.boot:	   zreladdr-y	:= 0x80008000
arch/arm/mach-omap2/Makefile.boot:	   zreladdr-y	:= 0x80008000
arch/arm/mach-pnx4008/Makefile.boot:	   zreladdr-y	:= 0x80008000
arch/arm/mach-mx5/Makefile.boot:	   zreladdr-y	:= 0x90008000
arch/arm/mach-mxc91231/Makefile.boot:	   zreladdr-y	:= 0x90008000
arch/arm/mach-iop32x/Makefile.boot:	   zreladdr-y	:= 0xa0008000
arch/arm/mach-pxa/Makefile.boot:	   zreladdr-y	:= 0xa0008000
arch/arm/mach-lh7a40x/Makefile.boot:	   zreladdr-y	:= 0xc0008000
arch/arm/mach-clps711x/Makefile.boot:	   zreladdr-y	:= 0xc0028000
arch/arm/mach-aaec2000/Makefile.boot:	   zreladdr-y	:= 0xf0008000
arch/arm/mach-l7200/Makefile.boot:	   zreladdr-y	:= 0xf0008000

Depends on other options/macros, but still can be auto calculated by
masking PC with 0xf000_0000:

arch/arm/mach-bcmring/Makefile.boot:	   zreladdr-y   := $(CONFIG_BCM_ZRELADDR)
* refer to arch/arm/configs/bcmring_defconfig:CONFIG_BCM_ZRELADDR=0x8000
arch/arm/mach-h720x/Makefile.boot:	   zreladdr-$(CONFIG_ARCH_H720X) := 0x40008000
arch/arm/mach-shmobile/Makefile.boot:	   zreladdr-y   := $(__ZRELADDR)
* __ZRELADDR depends on CONFIG_MEMORY_START
arch/arm/configs/ap4evb_defconfig:	CONFIG_MEMORY_START=0x40000000 (SH7372)
arch/arm/configs/g3evm_defconfig:	CONFIG_MEMORY_START=0x50000000 (SH7367)
arch/arm/configs/g4evm_defconfig:	CONFIG_MEMORY_START=0x40000000 (SH7377)

arch/arm/mach-at91/Makefile.boot:	   zreladdr-y	:= 0x70008000 (CONFIG_ARCH_AT91CAP9)
arch/arm/mach-at91/Makefile.boot:	   zreladdr-y	:= 0x70008000 (CONFIG_ARCH_AT91SAM9G45)
arch/arm/mach-at91/Makefile.boot:	   zreladdr-y	:= 0x20008000 (CONFIG_ARCH_AT91)
arch/arm/mach-davinci/Makefile.boot:	   zreladdr-y	:= 0xc0008000 (CONFIG_ARCH_DAVINCI_DA8XX)
arch/arm/mach-davinci/Makefile.boot:	   zreladdr-y	:= 0x80008000 (!CONFIG_ARCH_DAVINCI_DA8XX)
arch/arm/mach-ep93xx/Makefile.boot:	   zreladdr-$(CONFIG_EP93XX_SDCE3_SYNC_PHYS_OFFSET)	:= 0x00008000
arch/arm/mach-ep93xx/Makefile.boot:	   zreladdr-$(CONFIG_EP93XX_SDCE0_PHYS_OFFSET)		:= 0xc0008000
arch/arm/mach-ep93xx/Makefile.boot:	   zreladdr-$(CONFIG_EP93XX_SDCE1_PHYS_OFFSET)		:= 0xd0008000
arch/arm/mach-ep93xx/Makefile.boot:	   zreladdr-$(CONFIG_EP93XX_SDCE2_PHYS_OFFSET)		:= 0xe0008000
arch/arm/mach-ep93xx/Makefile.boot:	   zreladdr-$(CONFIG_EP93XX_SDCE3_ASYNC_PHYS_OFFSET)	:= 0xf0008000
arch/arm/mach-gemini/Makefile.boot:	   zreladdr-y	:= 0x00008000 (CONFIG_GEMINI_MEM_SWAP)
arch/arm/mach-gemini/Makefile.boot:	   zreladdr-y	:= 0x10008000 (!CONFIG_GEMINI_MEM_SWAP)
arch/arm/mach-mx2/Makefile.boot:	   zreladdr-$(CONFIG_MACH_MX21) := 0xC0008000
arch/arm/mach-mx2/Makefile.boot:	   zreladdr-$(CONFIG_MACH_MX27) := 0xA0008000
arch/arm/mach-realview/Makefile.boot:	   zreladdr-y	:= 0x70008000 (CONFIG_REALVIEW_HIGH_PHYS_OFFSET)
arch/arm/mach-realview/Makefile.boot:	   zreladdr-y	:= 0x00008000 (CONFIG_REALVIEW_HIGH_PHYS_OFFSET)
arch/arm/mach-sa1100/Makefile.boot:	   zreladdr-y	:= 0xc0008000
arch/arm/mach-sa1100/Makefile.boot:	   zreladdr-$(CONFIG_SA1111) := 0xc0208000

Machines where ZRELADDR cannot be auto calcuated:

arch/arm/mach-mx1/Makefile.boot:	   zreladdr-y	:= 0x08008000
arch/arm/mach-shark/Makefile.boot:	   zreladdr-y	:= 0x08008000
arch/arm/mach-u300/Makefile.boot:	   zreladdr-y	:= 0x28E08000
arch/arm/mach-u300/Makefile.boot:	   zreladdr-y	:= 0x48008000

Signed-off-by: Eric Miao <eric.miao at canonical.com>
---
 arch/arm/Kconfig                  |   63 +++++++++++++++++++++++++++++++++++++
 arch/arm/boot/Makefile            |   10 +++---
 arch/arm/boot/compressed/Makefile |    4 +-
 arch/arm/boot/compressed/head.S   |   12 +++++--
 4 files changed, 79 insertions(+), 10 deletions(-)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index e340193..818f731 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1497,6 +1497,69 @@ config TEXT_OFFSET
 	  TEXT_OFFSET is the offset of the decompressed kernel image from
 	  memory start. Currently, it is expected the least significant 16
 	  bits to be 0x8000, so to leave space for the initial page table.
+
+config AUTO_ZRELADDR
+	bool "Auto calculation of the decompressed kernel image address"
+	depends on !ZBOOT_ROM && !(ARCH_MX1 || ARCH_SHARK || ARCH_U300)
+	help
+	  ZRELADDR is the physical address where the decompressed kernel
+	  image will be placed. If AUTO_ZRELADDR is selected, the address
+	  will be determined at run-time by masking the current IP with
+	  0xf000_0000. This assumes the zImage being placed in the 256MB
+	  range from the start of memory.
+
+config ZRELADDR
+	hex "Physical address of the decompressed kernel image"
+	depends on !AUTO_ZRELADDR
+	default 0x00008000 if ARCH_BCMRING || ARCH_CNS3XXX || ARCH_DOVE ||\
+			      ARCH_EBSA110 || ARCH_FOOTBRIDGE || ARCH_INTEGRATOR ||\
+			      ARCH_IOP13XX || ARCH_IOP33X || ARCH_IXP2000 ||\
+			      ARCH_IXP23XX || ARCH_IXP4XX || ARCH_KIRKWOOD ||\
+			      ARCH_KS8695  || ARCH_LOKI || ARCH_MMP || ARCH_MV78XX0 ||\
+			      ARCH_NOMADIK || ARCH_NUC93X || ARCH_NS9XXX ||\
+			      ARCH_ORION5X || ARCH_SPEAR3XX || ARCH_SPEAR6XX ||\
+			      ARCH_UX5XX || ARCH_VERSATILE || ARCH_W90X900
+	default 0x08008000 if ARCH_MX1 || ARCH_SHARK
+	default 0x10008000 if ARCH_MSM || ARCH_OMAP1 || ARCH_RPC
+	default 0x20008000 if ARCH_S5P6440 || ARCH_S5P6442 ||\
+			      ARCH_S5PC100 || ARCH_S5PV210
+	default 0x30008000 if ARCH_S3C2410 || ARCH_S3C2400 || ARCH_S3C2412 ||\
+			      ARCH_S3C2416 || ARCH_S3C2440 || ARCH_S3C2443
+	default 0x40008000 if ARCH_STMP378X || ARCH_STMP37XX || ARCH_SH7372 ||\
+			      ARCH_SH7377
+	default 0x50008000 if ARCH_S3C64XX || ARCH_SH7367
+	default 0x60008000 if ARCH_VEXPRESS
+	default 0x80008000 if ARCH_MX25 || ARCH_MX3 || ARCH_NETX ||\
+			      ARCH_OMAP2 || ARCH_PNX4008
+	default 0x90008000 if ARCH_MX5 || ARCH_MX91231
+	default 0xa0008000 if ARCH_IOP32X || ARCH_PXA || MACH_MX27
+	default 0xc0008000 if ARCH_LH7A40X || MACH_MX21
+	default 0xf0008000 if ARCH_AAEC2000 || ARCH_L7200
+	default 0xc0028000 if ARCH_CLPS711X
+	default 0x70008000 if ARCH_AT91 && (ARCH_AT91CAP9 || ARCH_AT91SAM9G45)
+	default 0x20008000 if ARCH_AT91 && !(ARCH_AT91CAP9 || ARCH_AT91SAM9G45)
+	default 0xc0008000 if ARCH_DAVINCI && ARCH_DAVINCI_DA8XX
+	default 0x80008000 if ARCH_DAVINCI && !ARCH_DAVINCI_DA8XX
+	default 0x00008000 if ARCH_EP93XX && EP93XX_SDCE3_SYNC_PHYS_OFFSET
+	default 0xc0008000 if ARCH_EP93XX && EP93XX_SDCE0_PHYS_OFFSET
+	default 0xd0008000 if ARCH_EP93XX && EP93XX_SDCE1_PHYS_OFFSET
+	default 0xe0008000 if ARCH_EP93XX && EP93XX_SDCE2_PHYS_OFFSET
+	default 0xf0008000 if ARCH_EP93XX && EP93XX_SDCE3_ASYNC_PHYS_OFFSET
+	default 0x00008000 if ARCH_GEMINI && GEMINI_MEM_SWAP
+	default 0x10008000 if ARCH_GEMINI && !GEMINI_MEM_SWAP
+	default 0x70008000 if ARCH_REALVIEW && REALVIEW_HIGH_PHYS_OFFSET
+	default 0x00008000 if ARCH_REALVIEW && !REALVIEW_HIGH_PHYS_OFFSET
+	default 0xc0208000 if ARCH_SA1100 && SA1111
+	default 0xc0008000 if ARCH_SA1100 && !SA1111
+	default 0x30108000 if ARCH_S3C2410 && PM_H1940
+	default 0x28E08000 if ARCH_U300 && MACH_U300_SINGLE_RAM
+	default 0x48008000 if ARCH_U300 && !MACH_U300_SINGLE_RAM
+	help
+	  ZRELADDR is the physical address where the decompressed kernel
+	  image will be placed. ZRELADDR has to be specified when the
+	  assumption of AUTO_ZRELADDR is not valid, or when ZBOOT_ROM is
+	  selected.
+
 endmenu
 
 menu "CPU Power Management"
diff --git a/arch/arm/boot/Makefile b/arch/arm/boot/Makefile
index 4a590f4..8cc4669 100644
--- a/arch/arm/boot/Makefile
+++ b/arch/arm/boot/Makefile
@@ -14,18 +14,16 @@
 MKIMAGE         := $(srctree)/scripts/mkuboot.sh
 
 ifneq ($(MACHINE),)
-include $(srctree)/$(MACHINE)/Makefile.boot
+-include $(srctree)/$(MACHINE)/Makefile.boot
 endif
 
 # Note: the following conditions must always be true:
-#   ZRELADDR == virt_to_phys(PAGE_OFFSET + TEXT_OFFSET)
 #   PARAMS_PHYS must be within 4MB of ZRELADDR
 #   INITRD_PHYS must be in RAM
-ZRELADDR    := $(zreladdr-y)
 PARAMS_PHYS := $(params_phys-y)
 INITRD_PHYS := $(initrd_phys-y)
 
-export ZRELADDR INITRD_PHYS PARAMS_PHYS
+export INITRD_PHYS PARAMS_PHYS
 
 targets := Image zImage xipImage bootpImage uImage
 
@@ -67,7 +65,7 @@ quiet_cmd_uimage = UIMAGE  $@
 ifeq ($(CONFIG_ZBOOT_ROM),y)
 $(obj)/uImage: LOADADDR=$(CONFIG_ZBOOT_ROM_TEXT)
 else
-$(obj)/uImage: LOADADDR=$(ZRELADDR)
+$(obj)/uImage: LOADADDR=$(CONFIG_ZRELADDR)
 endif
 
 ifeq ($(CONFIG_THUMB2_KERNEL),y)
@@ -78,6 +76,8 @@ $(obj)/uImage: STARTADDR=$(LOADADDR)
 endif
 
 $(obj)/uImage:	$(obj)/zImage FORCE
+	@test "$(CONFIG_AUTO_ZRELADDR)" == "y" ||\
+	(echo CONFIG_ZRELADDR must be specified for uImage; exit -1)
 	$(call if_changed,uimage)
 	@echo '  Image $@ is ready'
 
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
index dbd3fe8..45b0f48 100644
--- a/arch/arm/boot/compressed/Makefile
+++ b/arch/arm/boot/compressed/Makefile
@@ -4,6 +4,8 @@
 # create a compressed vmlinuz image from the original vmlinux
 #
 
+AFLAGS_head.o        := -DTEXT_OFFSET=$(CONFIG_TEXT_OFFSET)
+
 HEAD	= head.o
 OBJS	= misc.o decompress.o
 FONTC	= $(srctree)/drivers/video/console/font_acorn_8x8.c
@@ -79,8 +81,6 @@ endif
 EXTRA_CFLAGS  := -fpic -fno-builtin
 EXTRA_AFLAGS  := -Wa,-march=all
 
-# Supply ZRELADDR to the decompressor via linker symbols.
-LDFLAGS_vmlinux := --defsym zreladdr=$(ZRELADDR)
 ifeq ($(CONFIG_CPU_ENDIAN_BE8),y)
 LDFLAGS_vmlinux += --be8
 endif
diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 0765990..17d19dc 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -170,9 +170,16 @@ not_angel:
 
 		.text
 		adr	r0, LC0
- ARM(		ldmia	r0, {r1, r2, r3, r4, r5, r6, r11, ip, sp})
- THUMB(		ldmia	r0, {r1, r2, r3, r4, r5, r6, r11, ip}	)
+ ARM(		ldmia	r0, {r1, r2, r3, r5, r6, r11, ip, sp})
+ THUMB(		ldmia	r0, {r1, r2, r3, r5, r6, r11, ip}	)
  THUMB(		ldr	sp, [r0, #32]				)
+#ifdef CONFIG_AUTO_ZRELADDR
+		@ determine final kernel image address
+		and	r4, pc, #0xf0000000
+		add	r4, r4, #TEXT_OFFSET
+#else
+		ldr	r4, =CONFIG_ZRELADDR
+#endif
 		subs	r0, r0, r1		@ calculate the delta offset
 
 						@ if delta is zero, we are
@@ -310,7 +317,6 @@ wont_overwrite:	mov	r0, r4
 LC0:		.word	LC0			@ r1
 		.word	__bss_start		@ r2
 		.word	_end			@ r3
-		.word	zreladdr		@ r4
 		.word	_start			@ r5
 		.word	_image_size		@ r6
 		.word	_got_start		@ r11
-- 
1.7.0.4


