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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-24 08:46:03 -0700
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Merge tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlgrafted
Pull pin control updates from Linus Walleij: "Core changes: - Use the non-blocking mux_state_try_select() in the generic MUX pin control back-end - Free pin maps on pinctrl_generic_to_map() failure in the core helpers New hardware pin control: - Qualcomm Maili TLMM SoC, PMG1110 PMIC, and Eliza LPASS LPI TLMM SoC (this is for the low power audio, LPASS = Low Power Audio SubSystem portions) - Upboard support on top of the Intel pin controller - Apple T6030 and T6031 support (just compatible strings) - Samsung Exynos 8855 SoC - Mediatek MT6858 SoC - Rockchip RK3308B and RV1106 SoCs - Airoha EN7523 and AN7563 SoCs Improvements: - Qualcomm TLMM GPIOs are unconditionally marked as wakeup capable - Qualcomm improvements on top of the Qualcomm PDC (power domain controller) irqchip improvements from tglx:s tree - Qualcomm IPQ806x and IPQ9650 non-urgent pin grop fixups - The NPCM8xx driver has been put into shape fixing many pin and group definitions - Some non-urgent Tegra 264 pin assignments are fixed up - Some non-urgent fixups to Airoha AN7581 and AN7583 registers and pin assignments, missing features etc" * tag 'pinctrl-v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (130 commits) dt-bindings: pinctrl: Convert TI DA850 pupd to DT schema pinctrl: meson: sync some modify from A4 pinctrl: meson: a4: Add input enable pin configuration pinctrl: realtek: rtd1625: remove unused group name spdif_sel pinctrl: realtek: rtd1625: fix base_bit for VE4 GPIO 13 dt-bindings: pinctrl: microchip,pic32mzda-pinctrl: Convert to DT schema Revert "Merge branch 'ib-rsk7204' into devel" pinctrl: rockchip: Add RV1106 pinctrl support dt-bindings: pinctrl: rockchip: Add RV1106 compatible pinctrl: rockchip: Decode drive strength in the get function pinctrl: fix PINCTRL_GENERIC_MUX not always being selectable pinctrl: airoha: add support of an7563 SoC dt-bindings: pinctrl: airoha: add support of an7563 pin controller pinctrl: airoha: try to find chip scu node by phandle first pinctrl: airoha: add support of en7523 SoC dt-bindings: pinctrl: airoha: add support of en7523 pin controller pinctrl: airoha: an7583: add support for olt pinmux pinctrl: airoha: an7583: add support for pon_alt pinmux pinctrl: airoha: an7583: add support for npu_uart pinmux dt-bindings: pinctrl: airoha: an7583: add missed features ...
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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.