[PATCH 11/11] Auto calculate ZRELADDR and provide option for exceptions

Mon Jul 5 11:31:13 EDT 2010

On Mon, 5 Jul 2010, Uwe Kleine-König wrote:

> From: Eric Miao <eric.miao at canonical.com>
> 
> As long as the zImage is placed within the 128MB range from the start of
> 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 0xf80000000.
> 
> Running through all the Makefile.boot, all those zreladdr-y
> addresses == 0x[0-f][08]00_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) & ~0xf8000000) != 0, which means
>   masking PC with 0xf8000000 will result in an incorrect address.
>   Currently this is only a problem on u300.
> 
> - or the assumption of the zImage being loaded by the bootloader within
>   the first 128MB of RAM is incorrect
> 
> - or when ZBOOT_ROM is used, where the above assumption is usually wrong.
> 
> [ukleinek: changed mask from 0xf0000000 to 0xf8000000 for mx1 and shark
> + some review fixes from the mailing list]
> 
> Signed-off-by: Eric Miao <eric.miao at canonical.com>
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>

Although Eric did all the work, the original idea was mine.  Therefore:

Signed-off-by: Nicolas Pitre <nicolas.pitre at linaro.org>

> ---
>  arch/arm/Kconfig                  |   99 +++++++++++++++++++++++++++++++++++++
>  arch/arm/boot/Makefile            |    8 +--
>  arch/arm/boot/compressed/Makefile |    3 +-
>  arch/arm/boot/compressed/head.S   |   12 +++-
>  4 files changed, 112 insertions(+), 10 deletions(-)
> 
> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> index a53ac65..0b0cf0d 100644
> --- a/arch/arm/Kconfig
> +++ b/arch/arm/Kconfig
> @@ -1490,6 +1490,105 @@ config ATAGS_PROC
>  	  Should the atags used to boot the kernel be exported in an "atags"
>  	  file in procfs. Useful with kexec.
>  
> +config AUTO_ZRELADDR
> +	bool "Auto calculation of the decompressed kernel image address"
> +	depends on !ZBOOT_ROM && !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
> +	  0xf8000000. This assumes the zImage being placed in the first 128MB
> +	  from 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_U8500 ||\
> +		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_OMAP2PLUS ||\
> +		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 264dccf..5e89c2c 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 := $(initrd_phys-y)
>  
> -export ZRELADDR INITRD_PHYS PARAMS_PHYS
> +export INITRD_PHYS PARAMS_PHYS
>  
>  targets := Image zImage xipImage bootpImage uImage
>  
> @@ -68,7 +66,7 @@ ifeq ($(CONFIG_RUNTIME_PHYS_OFFSET),)
>  ifeq ($(CONFIG_ZBOOT_ROM),y)
>  $(obj)/uImage: LOADADDR=$(CONFIG_ZBOOT_ROM_TEXT)
>  else
> -$(obj)/uImage: LOADADDR=$(ZRELADDR)
> +$(obj)/uImage: LOADADDR=$(CONFIG_ZRELADDR)
>  endif
>  endif
>  
> diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile
> index 2a80c9d..cc8380b 100644
> --- a/arch/arm/boot/compressed/Makefile
> +++ b/arch/arm/boot/compressed/Makefile
> @@ -4,6 +4,7 @@
>  # create a compressed vmlinuz image from the original vmlinux
>  #
>  
> +AFLAGS_head.o += -DTEXT_OFFSET=$(TEXT_OFFSET)
>  HEAD	= head.o
>  OBJS	= misc.o decompress.o
>  FONTC	= $(srctree)/drivers/video/console/font_acorn_8x8.c
> @@ -79,8 +80,6 @@ endif
>  EXTRA_CFLAGS  := -fpic -fno-builtin
>  EXTRA_AFLAGS  := -Wa,-march=all
>  
> -# Supply ZRELADDR to the decompressor via a linker symbol.
> -LDFLAGS_vmlinux := --defsym zreladdr=$(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 d27faa1..abf4d65 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, #0xf8000000
> +		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
> -- 
> 1.7.1
> 