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+Kernel initialisation parameters on ARM Linux
+---------------------------------------------
+
+The following document describes the kernel initialisation parameter
+structure, otherwise known as 'struct param_struct' which is used
+for most ARM Linux architectures.
+
+This structure is used to pass initialisation parameters from the
+kernel loader to the Linux kernel proper, and may be short lived
+through the kernel initialisation process. As a general rule, it
+should not be referenced outside of arch/arm/kernel/setup.c:setup_arch().
+
+There are a lot of parameters listed in there, and they are described
+below:
+
+ page_size
+
+ This parameter must be set to the page size of the machine, and
+ will be checked by the kernel.
+
+ nr_pages
+
+ This is the total number of pages of memory in the system. If
+ the memory is banked, then this should contain the total number
+ of pages in the system.
+
+ If the system contains separate VRAM, this value should not
+ include this information.
+
+ ramdisk_size
+
+ This is now obsolete, and should not be used.
+
+ flags
+
+ Various kernel flags, including:
+ bit 0 - 1 = mount root read only
+ bit 1 - unused
+ bit 2 - 0 = load ramdisk
+ bit 3 - 0 = prompt for ramdisk
+
+ rootdev
+
+ major/minor number pair of device to mount as the root filesystem.
+
+ video_num_cols
+ video_num_rows
+
+ These two together describe the character size of the dummy console,
+ or VGA console character size. They should not be used for any other
+ purpose.
+
+ It's generally a good idea to set these to be either standard VGA, or
+ the equivalent character size of your fbcon display. This then allows
+ all the bootup messages to be displayed correctly.
+
+ video_x
+ video_y
+
+ This describes the character position of cursor on VGA console, and
+ is otherwise unused. (should not be used for other console types, and
+ should not be used for other purposes).
+
+ memc_control_reg
+
+ MEMC chip control register for Acorn Archimedes and Acorn A5000
+ based machines. May be used differently by different architectures.
+
+ sounddefault
+
+ Default sound setting on Acorn machines. May be used differently by
+ different architectures.
+
+ adfsdrives
+
+ Number of ADFS/MFM disks. May be used differently by different
+ architectures.
+
+ bytes_per_char_h
+ bytes_per_char_v
+
+ These are now obsolete, and should not be used.
+
+ pages_in_bank[4]
+
+ Number of pages in each bank of the systems memory (used for RiscPC).
+ This is intended to be used on systems where the physical memory
+ is non-contiguous from the processors point of view.
+
+ pages_in_vram
+
+ Number of pages in VRAM (used on Acorn RiscPC). This value may also
+ be used by loaders if the size of the video RAM can't be obtained
+ from the hardware.
+
+ initrd_start
+ initrd_size
+
+ This describes the kernel virtual start address and size of the
+ initial ramdisk.
+
+ rd_start
+
+ Start address in sectors of the ramdisk image on a floppy disk.
+
+ system_rev
+
+ system revision number.
+
+ system_serial_low
+ system_serial_high
+
+ system 64-bit serial number
+
+ mem_fclk_21285
+
+ The speed of the external oscillator to the 21285 (footbridge),
+ which control's the speed of the memory bus, timer & serial port.
+ Depending upon the speed of the cpu its value can be between
+ 0-66 MHz. If no params are passed or a value of zero is passed,
+ then a value of 50 Mhz is the default on 21285 architectures.
+
+ paths[8][128]
+
+ These are now obsolete, and should not be used.
+
+ commandline
+
+ Kernel command line parameters. Details can be found elsewhere.