[U-Boot] [PATCH V6] BOOT: Add "bootz" command to boot Linux zImage on ARM

[Rob Herring <robherring2@gmail.com>]

On 03/15/2012 02:52 AM, Marek Vasut wrote:
> From: Marek Vasut <marek.vasut@gmail.com>
> 
> This command boots Linux zImage from where the zImage is loaded to. Passing
> initrd and fdt is supported.
> 

This is great! However, the initrd is still in the u-boot image format,
right?

If a raw initrd is supported, then we could get rid of flash-kernel on
disk-based debian/ubuntu systems. The file size is known from the
filesystem, but then needs to get to the bootz command somehow.

Rob

> Tested on i.MX28 based DENX M28EVK
> Tested on PXA270 based Voipac PXA270.
> 
> NOTE: This currently only supports ARM, but other architectures can be easily
> added by defining bootz_setup().
> 
> Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
> Cc: Tom Warren <TWarren@nvidia.com>
> Cc: albert.u.boot at aribaud.net
> Cc: afleming at gmail.com,
> Cc: Simon Glass <sjg@chromium.org>,
> Cc: Stephen Warren <swarren@nvidia.com>
> Cc: Nicolas Pitre <nico@fluxnic.net>
> Cc: Wolfgang Denk <wd@denx.de>
> Cc: Detlev Zundel <dzu@denx.de>
> ---
>  README                   |    8 +++
>  arch/arm/lib/bootm.c     |   30 ++++++++++
>  common/cmd_bootm.c       |  141 +++++++++++++++++++++++++++++++++++++++++++---
>  include/config_cmd_all.h |    1 +
>  4 files changed, 171 insertions(+), 9 deletions(-)
> 
> V2: Use CONFIG_BOOTZ_MAX_KERNEL_LMB_SIZE to reserve kernel LMB
> V3: Compute the LMB size at runtime (obsoletes V2)
>     Move shared code to image.c/image.h
>     Sync with latest U-Boot
> V4: Add all this into cmd_bootm. Therefore, this is part of cmd_bootm (basically
>     it's stripped-down version). Also, separate out arm-specific component into
>     arm-specific location.
> V5: Staticize bootz_setup(), add information into README.
> V6: Make cmd_bootz() static.
> 
> diff --git a/README b/README
> index 4021715..b273070 100644
> --- a/README
> +++ b/README
> @@ -3594,6 +3594,7 @@ go	- start application at address 'addr'
>  run	- run commands in an environment variable
>  bootm	- boot application image from memory
>  bootp	- boot image via network using BootP/TFTP protocol
> +bootz   - boot zImage from memory
>  tftpboot- boot image via network using TFTP protocol
>  	       and env variables "ipaddr" and "serverip"
>  	       (and eventually "gatewayip")
> @@ -4414,6 +4415,13 @@ U-Boot supports the following image types:
>  	useful when you configure U-Boot to use a real shell (hush)
>  	as command interpreter.
>  
> +Booting the Linux zImage:
> +-------------------------
> +
> +On some platforms, it's possible to boot Linux zImage. This is done
> +using the "bootz" command. The syntax of "bootz" command is the same
> +as the syntax of "bootm" command.
> +
>  
>  Standalone HOWTO:
>  =================
> diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
> index afa0093..ec46d76 100644
> --- a/arch/arm/lib/bootm.c
> +++ b/arch/arm/lib/bootm.c
> @@ -344,3 +344,33 @@ static ulong get_sp(void)
>  	asm("mov %0, sp" : "=r"(ret) : );
>  	return ret;
>  }
> +
> +#ifdef CONFIG_CMD_BOOTZ
> +
> +struct zimage_header {
> +	uint32_t	code[9];
> +	uint32_t	zi_magic;
> +	uint32_t	zi_start;
> +	uint32_t	zi_end;
> +};
> +
> +#define	LINUX_ARM_ZIMAGE_MAGIC	0x016f2818
> +
> +int bootz_setup(void *image, void **start, void **end)
> +{
> +	struct zimage_header *zi = (struct zimage_header *)image;
> +
> +	if (zi->zi_magic != LINUX_ARM_ZIMAGE_MAGIC) {
> +		puts("Bad Linux ARM zImage magic!\n");
> +		return 1;
> +	}
> +
> +	*start = (void *)zi->zi_start;
> +	*end = (void *)zi->zi_end;
> +
> +	debug("Kernel image @ 0x%08x [ 0x%08x - 0x%08x ]\n",
> +		(uint32_t)image, (uint32_t)*start, (uint32_t)*end);
> +
> +	return 0;
> +}
> +#endif	/* CONFIG_CMD_BOOTZ */
> diff --git a/common/cmd_bootm.c b/common/cmd_bootm.c
> index d5745b1..b49d4f7 100644
> --- a/common/cmd_bootm.c
> +++ b/common/cmd_bootm.c
> @@ -169,25 +169,25 @@ void arch_preboot_os(void) __attribute__((weak, alias("__arch_preboot_os")));
>  
>  #define IH_INITRD_ARCH IH_ARCH_DEFAULT
>  
> -static void bootm_start_lmb(void)
> -{
>  #ifdef CONFIG_LMB
> +static void boot_start_lmb(bootm_headers_t *images)
> +{
>  	ulong		mem_start;
>  	phys_size_t	mem_size;
>  
> -	lmb_init(&images.lmb);
> +	lmb_init(&images->lmb);
>  
>  	mem_start = getenv_bootm_low();
>  	mem_size = getenv_bootm_size();
>  
> -	lmb_add(&images.lmb, (phys_addr_t)mem_start, mem_size);
> +	lmb_add(&images->lmb, (phys_addr_t)mem_start, mem_size);
>  
> -	arch_lmb_reserve(&images.lmb);
> -	board_lmb_reserve(&images.lmb);
> +	arch_lmb_reserve(&images->lmb);
> +	board_lmb_reserve(&images->lmb);
> +}
>  #else
> -# define lmb_reserve(lmb, base, size)
> +static inline void boot_start_lmb(bootm_headers_t *images) { }
>  #endif
> -}
>  
>  static int bootm_start(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
>  {
> @@ -197,7 +197,7 @@ static int bootm_start(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]
>  	memset((void *)&images, 0, sizeof(images));
>  	images.verify = getenv_yesno("verify");
>  
> -	bootm_start_lmb();
> +	boot_start_lmb(&images);
>  
>  	/* get kernel image header, start address and length */
>  	os_hdr = boot_get_kernel(cmdtp, flag, argc, argv,
> @@ -1523,3 +1523,126 @@ static int do_bootm_integrity(int flag, int argc, char * const argv[],
>  	return 1;
>  }
>  #endif
> +
> +#ifdef CONFIG_CMD_BOOTZ
> +
> +static int __bootz_setup(void *image, void **start, void **end)
> +{
> +	/* Please define bootz_setup() for your platform */
> +
> +	puts("Your platform's zImage format isn't supported yet!\n");
> +	return -1;
> +}
> +int bootz_setup(void *image, void **start, void **end)
> +	__attribute__((weak, alias("__bootz_setup")));
> +
> +/*
> + * zImage booting support
> + */
> +static int bootz_start(cmd_tbl_t *cmdtp, int flag, int argc,
> +			char * const argv[], bootm_headers_t *images)
> +{
> +	int ret;
> +	void *zi_start, *zi_end;
> +
> +	memset(images, 0, sizeof(bootm_headers_t));
> +
> +	boot_start_lmb(images);
> +
> +	/* Setup Linux kernel zImage entry point */
> +	if (argc < 2) {
> +		images->ep = load_addr;
> +		debug("*  kernel: default image load address = 0x%08lx\n",
> +				load_addr);
> +	} else {
> +		images->ep = simple_strtoul(argv[1], NULL, 16);
> +		debug("*  kernel: cmdline image address = 0x%08lx\n",
> +			images->ep);
> +	}
> +
> +	ret = bootz_setup((void *)images->ep, &zi_start, &zi_end);
> +	if (ret != 0)
> +		return 1;
> +
> +	lmb_reserve(&images->lmb, images->ep, zi_end - zi_start);
> +
> +	/* Find ramdisk */
> +	ret = boot_get_ramdisk(argc, argv, images, IH_INITRD_ARCH,
> +			&images->rd_start, &images->rd_end);
> +	if (ret) {
> +		puts("Ramdisk image is corrupt or invalid\n");
> +		return 1;
> +	}
> +
> +#if defined(CONFIG_OF_LIBFDT)
> +	/* find flattened device tree */
> +	ret = boot_get_fdt(flag, argc, argv, images,
> +			   &images->ft_addr, &images->ft_len);
> +	if (ret) {
> +		puts("Could not find a valid device tree\n");
> +		return 1;
> +	}
> +
> +	set_working_fdt_addr(images->ft_addr);
> +#endif
> +
> +	return 0;
> +}
> +
> +static int do_bootz(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> +{
> +	ulong		iflag;
> +	bootm_headers_t	images;
> +
> +	if (bootz_start(cmdtp, flag, argc, argv, &images))
> +		return 1;
> +
> +	/*
> +	 * We have reached the point of no return: we are going to
> +	 * overwrite all exception vector code, so we cannot easily
> +	 * recover from any failures any more...
> +	 */
> +	iflag = disable_interrupts();
> +
> +#if defined(CONFIG_CMD_USB)
> +	/*
> +	 * turn off USB to prevent the host controller from writing to the
> +	 * SDRAM while Linux is booting. This could happen (at least for OHCI
> +	 * controller), because the HCCA (Host Controller Communication Area)
> +	 * lies within the SDRAM and the host controller writes continously to
> +	 * this area (as busmaster!). The HccaFrameNumber is for example
> +	 * updated every 1 ms within the HCCA structure in SDRAM! For more
> +	 * details see the OpenHCI specification.
> +	 */
> +	usb_stop();
> +#endif
> +
> +#ifdef CONFIG_SILENT_CONSOLE
> +	fixup_silent_linux();
> +#endif
> +	arch_preboot_os();
> +
> +	do_bootm_linux(0, argc, argv, &images);
> +#ifdef DEBUG
> +	puts("\n## Control returned to monitor - resetting...\n");
> +#endif
> +	do_reset(cmdtp, flag, argc, argv);
> +
> +	return 1;
> +}
> +
> +U_BOOT_CMD(
> +	bootz,	CONFIG_SYS_MAXARGS,	1,	do_bootz,
> +	"boot Linux zImage image from memory",
> +	"[addr [initrd] [fdt]]\n    - boot Linux zImage stored in memory\n"
> +	"\tThe argument 'initrd' is optional and specifies the address\n"
> +	"\tof the initrd in memory.\n"
> +#if defined(CONFIG_OF_LIBFDT)
> +	"\tWhen booting a Linux kernel which requires a flat device-tree\n"
> +	"\ta third argument is required which is the address of the\n"
> +	"\tdevice-tree blob. To boot that kernel without an initrd image,\n"
> +	"\tuse a '-' for the second argument. If you do not pass a third\n"
> +	"\ta bd_info struct will be passed instead\n"
> +#endif
> +);
> +#endif	/* CONFIG_CMD_BOOTZ */
> diff --git a/include/config_cmd_all.h b/include/config_cmd_all.h
> index 9716f9c..2c6b829 100644
> --- a/include/config_cmd_all.h
> +++ b/include/config_cmd_all.h
> @@ -20,6 +20,7 @@
>  #define CONFIG_CMD_BEDBUG	/* Include BedBug Debugger	*/
>  #define CONFIG_CMD_BMP		/* BMP support			*/
>  #define CONFIG_CMD_BOOTD	/* bootd			*/
> +#define CONFIG_CMD_BOOTZ	/* boot zImage			*/
>  #define CONFIG_CMD_BSP		/* Board Specific functions	*/
>  #define CONFIG_CMD_CACHE	/* icache, dcache		*/
>  #define CONFIG_CMD_CDP		/* Cisco Discovery Protocol	*/