linux-dev/arch/m68k/68000, branch linus/master

m68knommu: fix ucsimm sparse warnings

2022-03-07T04:51:12Z

Sparse reports the following warnings: arch/m68k/68000/ucsimm.c:19:15: sparse: sparse: symbol 'cs8900a_hwaddr' was not declared. Should it be static? arch/m68k/68000/ucsimm.c:22:1: sparse: sparse: symbol 'getserialnum' was not declared. Should it be static? arch/m68k/68000/ucsimm.c:23:1: sparse: sparse: symbol 'gethwaddr' was not declared. Should it be static? arch/m68k/68000/ucsimm.c:24:1: sparse: sparse: symbol 'getbenv' was not declared. Should it be static? 'cs8900a_hwaddr' is not used anywhere else in the kernel, so it can be removed. All of 'getserialnum', 'gethwaddr' and 'getbenv' are only used in this file, so they can all be made static. It turns out that these also cause compiler warnings like this too: arch/m68k/68000/ucsimm.c:22:15: warning: no previous prototype for 'getserialnum' [-Wmissing-prototypes] Also fixed by making them all static. Signed-off-by: Greg Ungerer Reported-by: kernel test robot

m68knommu: fix 'screen_bits' defined but not used

2022-03-07T04:51:11Z

The 'screen_bits' LCD initializer bit array is only required if CONFIG_INIT_LCD is enabled, otherwise we get the following warning: arch/m68k/68000/screen.h:4:22: warning: 'screen_bits' defined but not used [-Wunused-variable] static unsigned char screen_bits[] = { ^~~~~~~~~~~ Make the inclusion of 'screen_bits' conditional on CONFIG_INIT_LCD. Signed-off-by: Greg Ungerer Reported-by: kernel test robot

m68knommu: fix warning: no previous prototype for 'init_dragen2'

2022-03-07T04:51:11Z

Fix the compile time warning: arch/m68k/68000/dragen2.c:38:13: warning: no previous prototype for 'init_dragen2' [-Wmissing-prototypes] 38 | void __init init_dragen2(char *command, int size) | ^~~~~~~~~~~~ There already exists a header file prototype, but that file was not included in the dragen2.c code. Signed-off-by: Greg Ungerer Reported-by: kernel test robot

m68k: Remove set_fs()

2021-09-24T11:35:07Z

Add a m68k-only set_fc helper to set the SFC and DFC registers for the few places that need to override it for special MM operations, but disconnect that from the deprecated kernel-wide set_fs() API. Note that the SFC/DFC registers are context switched, so there is no need to disable preemption. Partially based on an earlier patch from Linus Torvalds . Signed-off-by: Christoph Hellwig Reviewed-by: Michael Schmitz Tested-by: Michael Schmitz Link: https://lore.kernel.org/r/20210916070405.52750-7-hch@lst.de Signed-off-by: Geert Uytterhoeven

m68k: Leave stack mangling to asm wrapper of sigreturn()

2021-09-24T11:35:03Z

sigreturn has to deal with an unpleasant problem - exception stack frames have different sizes, depending upon the exception (and processor model, as well) and variable-sized part of exception frame may contain information needed for instruction restart. So when signal handler terminates and calls sigreturn to resume the execution at the place where we'd been when we caught the signal, it has to rearrange the frame at the bottom of kernel stack. Worse, it might need to open a gap in the kernel stack, shifting pt_regs towards lower addresses. Doing that from C is insane - we'd need to shift stack frames (return addresses, local variables, etc.) of C call chain, right under the nose of compiler and hope it won't fall apart horribly. What had been actually done is only slightly less insane - an inline asm in mangle_kernel_stack() moved the stuff around, then reset stack pointer and jumped to label in asm glue. However, we can avoid all that mess if the asm wrapper we have to use anyway would reserve some space on the stack between switch_stack and the C stack frame of do_{rt_,}sigreturn(). Then C part can simply memmove() pt_regs + switch_stack, memcpy() the variable part of exception frame into the opened gap - all of that without inline asm, buggering C call chain, magical jumps to asm labels, etc. Asm wrapper would need to know where the moved switch_stack has ended up - it might have been shifted into the gap we'd reserved before do_rt_sigreturn() call. That's where it needs to set the stack pointer to. So let the C part return just that and be done with that. While we are at it, the call of berr_040cleanup() we need to do when returning via 68040 bus error exception frame can be moved into C part as well. Signed-off-by: Al Viro Tested-by: Michael Schmitz Reviewed-by: Michael Schmitz Tested-by: Finn Thain Link: https://lore.kernel.org/r/YP2dTQPm1wGPWFgD@zeniv-ca.linux.org.uk Signed-off-by: Geert Uytterhoeven

m68knommu: fix missing LCD splash screen data initializer

2021-06-21T02:09:26Z

The kernel test robot reports that the "screen_bits" splash screen data is missing for the dragen platform: arch/m68k/68000/dragen2.c:73:16: error: 'screen_bits' undeclared (first use in this function) 73 | LSSA = (long) screen_bits; | ^~~~~~~~~~~ arch/m68k/68000/dragen2.c:73:16: note: each undeclared identifier is reported only once for each function it appears in Digging around a bit I found the screen_bits data structure was originally in a screen.h file that was generated from a screen.xbm file. That was removed in commit 0c0e6db80683 ("m68k: drop unused parts of 68VZ328 Makefile"). Other splash screen initializers for 68000 targets are kept here as the C data structures so lets do the same for this one. Add the missing screen.h file and include it in the dragen specific startup code. Reported-by: kernel test robot Signed-off-by: Greg Ungerer Acked-by: Arnd Bergmann

Merge tag 'm68knommu-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu

2020-12-21T18:35:11Z

Pull m68knommu updates from Greg Ungerer: - cleanup of 68328 code - align BSS section to 32bit * tag 'm68knommu-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68k: m68328: remove duplicate code m68k: m68328: move platform code to separate files m68knommu: align BSS section to 4-byte boundaries

m68k: m68328: remove duplicate code

2020-12-06T23:37:58Z

Building a kernel with multiple dragonball based boards enabled needlessly causes a link failure because of duplicate config_BSP() functions between the CPU versions. Avoid that merging the three almost identical files into one, and hiding the CPU configuration behind the board config. The pr_info() lines are consolidated in one place. It is still not possible to run a kernel configured for more than one board, but at least configurations that can be selected can also be built now. Signed-off-by: Arnd Bergmann Signed-off-by: Greg Ungerer

m68k: m68328: move platform code to separate files

2020-12-06T23:37:58Z

The dragen2 and ucsimm/ucdimm files require a bit of custom code compared to the other dragonball platforms, move them into separate files as a preparation for a build fix. Signed-off-by: Arnd Bergmann Signed-off-by: Greg Ungerer

m68k: remove timer_interrupt() function

2020-10-30T20:57:06Z

This gets passed to a number of init functions, but is ignored everywhere, so remove the function and change the mach_sched_init callback to take no arguments. Reviewed-by: Geert Uytterhoeven Acked-by: Geert Uytterhoeven Tested-by: Geert Uytterhoeven Reviewed-by: Linus Walleij Signed-off-by: Arnd Bergmann