kernel/linux.git/include/linux/nubus.h, branch v6.6.132

nubus: Don't list slot resources by default

2023-05-22T11:51:56+00:00

Some Nubus card ROMs contain many slot resources. A single Radius video card produced well over a thousand entries under /proc/bus/nubus/. Populating /proc/bus/nubus/ on a slow machine with several such cards installed takes long enough that the user may think that the system is wedged. All those procfs entries also consume significant RAM though they are not normally needed (except by developers). Omit these resources from /proc/bus/nubus/ by default and add a kernel parameter to enable them when needed. On the test machine, this saved 300 kB and 10 seconds. Cc: Brad Boyer Reviewed-by: Brad Boyer Tested-by: Stan Johnson Signed-off-by: Finn Thain Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/71ed7fb234a5f7381a50253b0d841a656d53e64c.1684200125.git.fthain@linux-m68k.org Signed-off-by: Geert Uytterhoeven

nubus: Make struct nubus_driver::remove return void

2021-07-28T13:33:59+00:00

The nubus core ignores the return value of the remove callback (in nubus_device_remove()) and all implementers return 0 anyway. So make it impossible for future drivers to return an unused error code by changing the remove prototype to return void. Signed-off-by: Uwe Kleine-König Acked-by: Finn Thain Link: https://lore.kernel.org/r/20210727080840.3550927-3-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

nubus: Call bus_register unconditionally

2018-05-14T14:27:08+00:00

Loading a NuBus driver module on a non-NuBus machine triggers the BUG_ON(!drv->bus->p) in driver_register(), because bus_register() was not called, because it is conditional on MACH_IS_MAC. Fix the crash by calling bus_register() unconditionally. Call it from a postcore_initcall(), like other busses do. Hence, the bus type is available for device_register(), which happens in a subsys initcall, and for driver_register(), which happens in a device or module initcall. Cc: Greg Kroah-Hartman Reported-by: Michael Schmitz Tested-by: Stan Johnson Fixes: 7f86c765a6a2 ("nubus: Add support for the driver model") Signed-off-by: Finn Thain Reviewed-by: Geert Uytterhoeven Signed-off-by: Greg Kroah-Hartman

nubus: Add support for the driver model

2018-01-16T15:47:29+00:00

This patch brings basic support for the Linux Driver Model to the NuBus subsystem. For flexibility, the matching of boards with drivers is left up to the drivers. This is also the approach taken by NetBSD. A board may have many functions, and drivers may have to consider many functional resources and board resources in order to match a device. This implementation does not bind drivers to resources (nor does it bind many drivers to the same board). Apple's NuBus declaration ROM design is flexible enough to allow that, but I don't see a need to support it as we don't use the "slot zero" resources (in the main logic board ROM). Eliminate the global nubus_boards linked list by rewriting the procfs board iterator around bus_for_each_dev(). Hence the nubus device refcount can be used to determine the lifespan of board objects. Cc: Greg Kroah-Hartman Reviewed-by: Greg Kroah-Hartman Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Adopt standard linked list implementation

2018-01-16T15:47:29+00:00

This increases code re-use and improves readability. Cc: "David S. Miller" Cc: Bartlomiej Zolnierkiewicz Acked-by: Bartlomiej Zolnierkiewicz Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Rename struct nubus_dev

2018-01-16T15:47:29+00:00

It is misleading to call a functional resource a "device". In adopting the Linux Driver Model, the struct device will be embedded in struct nubus_board. That will compound the terminlogy problem because drivers will bind with boards, not with functional resources. Avoid this by renaming struct nubus_dev as struct nubus_rsrc. "Functional resource" is the vendor's terminology so this helps avoid confusion. Cc: "David S. Miller" Cc: Bartlomiej Zolnierkiewicz Acked-by: Bartlomiej Zolnierkiewicz Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Rework /proc/bus/nubus/s/ implementation

2018-01-16T15:47:29+00:00

The /proc/bus/nubus/s/ directory tree for any slot s is missing a lot of information. The struct file_operations methods have long been left unimplemented (hence the familiar compile-time warning, "Need to set some I/O handlers here"). Slot resources have a complex structure which varies depending on board function. The logic for interpreting these ROM data structures is found in nubus.c. Let's not duplicate that logic in proc.c. Create the /proc/bus/nubus/s/ inodes while scanning slot s. During descent through slot resource subdirectories, call the new nubus_proc_add_foo() functions to create the procfs inodes. Also add a new function, nubus_seq_write_rsrc_mem(), to write the contents of a particular slot resource to a given seq_file. This is used by the procfs file_operations methods, to finally give userspace access to slot ROM information, such as the available video modes. Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Clean up whitespace

2018-01-16T15:47:29+00:00

Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Remove redundant code

2018-01-16T15:47:29+00:00

Eliminate unused values from struct nubus_dev to save wasted memory (a Radius PrecisionColor 24X card has about 95 functional resources and up to six such cards may be fitted). Also remove redundant static variable initialization, an unreachable !MACH_IS_MAC conditional, the unused nubus_find_device() function, the bogus get_nubus_list() prototype and the pointless card_present temporary variable. Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven

nubus: Call proc_mkdir() not more than once per slot directory

2018-01-16T15:47:29+00:00

This patch fixes the following WARNING. proc_dir_entry 'nubus/a' already registered Modules linked in: CPU: 0 PID: 1 Comm: swapper Tainted: G W 4.13.0-00036-gd57552077387 #1 Stack from 01c1bd9c: 01c1bd9c 003c2c8b 01c1bdc0 0001b0fe 00000000 00322f4a 01c43a20 01c43b0c 01c8c420 01c1bde8 0001b1b8 003a4ac3 00000148 000faa26 00000009 00000000 01c1bde0 003a4b6c 01c1bdfc 01c1be20 000faa26 003a4ac3 00000148 003a4b6c 01c43a71 01c8c471 01c10000 00326430 0043d00c 00000005 01c71a00 0020bce0 00322964 01c1be38 000fac04 01c43a20 01c8c420 01c1bee0 01c8c420 01c1be50 000fac4c 01c1bee0 00000000 01c43a20 00000000 01c1bee8 0020bd26 01c1bee0 Call Trace: [<0001b0fe>] __warn+0xae/0xde [<00322f4a>] memcmp+0x0/0x5c [<0001b1b8>] warn_slowpath_fmt+0x2e/0x36 [<000faa26>] proc_register+0xbe/0xd8 [<000faa26>] proc_register+0xbe/0xd8 [<00326430>] sprintf+0x0/0x20 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8 [<00322964>] strcpy+0x0/0x22 [<000fac04>] proc_mkdir_data+0x64/0x96 [<000fac4c>] proc_mkdir+0x16/0x1c [<0020bd26>] nubus_proc_attach_device+0x46/0x1b8 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8 [<00322964>] strcpy+0x0/0x22 [<00001ba6>] kernel_pg_dir+0xba6/0x1000 [<004339a2>] proc_bus_nubus_add_devices+0x1a/0x2e [<000faa40>] proc_create_data+0x0/0xf2 [<0003297c>] parse_args+0x0/0x2d4 [<00433a08>] nubus_proc_init+0x52/0x5a [<00433944>] nubus_init+0x0/0x44 [<00433982>] nubus_init+0x3e/0x44 [<000020dc>] do_one_initcall+0x38/0x196 [<000020a4>] do_one_initcall+0x0/0x196 [<0003297c>] parse_args+0x0/0x2d4 [<00322964>] strcpy+0x0/0x22 [<00040004>] __up_read+0xe/0x40 [<004231d4>] repair_env_string+0x0/0x7a [<0042312e>] kernel_init_freeable+0xee/0x194 [<00423146>] kernel_init_freeable+0x106/0x194 [<00433944>] nubus_init+0x0/0x44 [<000a6000>] kfree+0x0/0x156 [<0032768c>] kernel_init+0x0/0xda [<00327698>] kernel_init+0xc/0xda [<0032768c>] kernel_init+0x0/0xda [<00002a90>] ret_from_kernel_thread+0xc/0x14 ---[ end trace 14a6d619908ea253 ]--- ------------[ cut here ]------------ This gets repeated with each additional functional reasource. The problem here is the call to proc_mkdir() when the directory already exists. Each nubus_board gets a directory, such as /proc/bus/nubus/s/ where s is the hex slot number. Therefore, store the 'procdir' pointer in struct nubus_board instead of struct nubus_dev. Tested-by: Stan Johnson Signed-off-by: Finn Thain Signed-off-by: Geert Uytterhoeven