[PATCH 00/27] sparc32: sunset sun4m and sun4d

From: Sam Ravnborg via B4 Relay
Date: Tue Dec 19 2023 - 17:04:28 EST

This is the second attempt to sunset sun4m and sun4d.
See [1] for the inital attempt.

The sun4m and sun4d parts of the kernel have seen no real interest
for several years now. Last time a few people surfaced, but it was
either due to a personal project or for nostalgic reasons.
It is time to let go and drop the parts of sparc32 that in reality
are not in use.

LEON from Frontgrade Gaisler is the only real user of sparc32,
and this patchset reduces sparc32 to what is required by LEON.

The defconfig is first adapted to the one used by Gaisler.
Then the patches removes sun4m and sun4d specific
implementations such as small drivers, SMP support, IRQ suppor etc.

Removing sun4m and sun4d support allowed removal of the run time
patching of the code as well as a lot of assembler code.
The result is a much cleaner assembler code that is easier to
understand and thus maintain and extend.

So far the code builds but it has seen no run-time testing.

If anyone can tell me how to boot a linux kernel with the leon_genric
machine with QEMU that would be super as this would be a minimal
testing that others can reproduce as well.
I assume QEMU needs a few patches to make it work, but maybe I
just failed to use the right bootloader.

TODO before this can be applied:
- Ack from davem - as he is the principal sparc maintainer
- Tested-by: preferably on a target or QEMU (see above)
I expect bugs as there are some involved changes!

Ideas for the future
- Apply the most relevant downstream Gaisler patches
- The ones introducing CAS should have preference as we then
can drop the cmpxchg emulation
- Adjust defconfig to include all Gaisler drivers to make sure they
see build time coverage
- Move the leon bits from leon files to the general files
- Add leon smp support to smp_32.c
- Add leon irq support to irq_32.c
- Integrate leom_mm support with srmmu and drop some of the
function operations that are no longer needed
- The current sparc32 code assume the bootloader uses the prom
provided by sun. Maybe migrate over to a more modern device tree
way of working.
- Drop some of the homegrown memory allocators and use memblocks

[1]: https://lore.kernel.org/all/20201218184347.2180772-1-sam@xxxxxxxxxxxx/

Sam

---
Sam Ravnborg (27):
sparc32: Update defconfig to LEON SMP
sparc32: Drop sun4m/sun4d support from head_32.S
sparc32: Drop floppy support
sparc32: Drop sun4m specific led driver
sparc32: Drop sun specific power management drivers
sparc32: Drop auxio support
sparc32: Drop run-time patching of ipi trap
sparc32: Drop patching of interrupt vector
sparc32: Drop sun4m/sun4d specific irq handling
sparc32: Drop sun4d/sun4m smp support
sparc32: Drop pcic support
sparc32: Drop mbus support
sparc32: Drop unused function __get_{phys,iospace}
sparc32: Drop unused mmu models
sparc32: Drop check for sparc_model
sparc32: Drop use of sparc_config
sparc32: Drop run-time patching of ASI instructions
sparc32: Drop support for 7 register windows
sparc32: Drop additional sun4d bits
sparc32: Drop unused prom ranges support
sparc32: Drop unused iommu support
sparc32: Drop sun4m irq support
sparc32: Drop unused trampoline code
sparc32: Drop config SPARC_LEON
sparc32: Drop sbus support
sbus: char: Drop now unused uctrl driver
fbdev/p9100: Drop now unused driver p9100

arch/sparc/Kconfig | 54 +--
arch/sparc/configs/sparc32_defconfig | 170 +++----
arch/sparc/include/asm/asmmacro.h | 22 -
arch/sparc/include/asm/auxio_32.h | 73 +--
arch/sparc/include/asm/cpu_type.h | 18 -
arch/sparc/include/asm/elf_32.h | 2 -
arch/sparc/include/asm/fb.h | 8 +-
arch/sparc/include/asm/floppy.h | 2 -
arch/sparc/include/asm/floppy_32.h | 393 ----------------
arch/sparc/include/asm/io-unit.h | 59 ---
arch/sparc/include/asm/io_32.h | 83 ----
arch/sparc/include/asm/iommu.h | 2 -
arch/sparc/include/asm/iommu_32.h | 122 -----
arch/sparc/include/asm/irq_32.h | 2 -
arch/sparc/include/asm/mbus.h | 97 ----
arch/sparc/include/asm/mxcc.h | 138 ------
arch/sparc/include/asm/obio.h | 226 ---------
arch/sparc/include/asm/oplib_32.h | 11 -
arch/sparc/include/asm/pcic.h | 130 ------
arch/sparc/include/asm/pgtable_32.h | 24 -
arch/sparc/include/asm/pgtsrmmu.h | 33 +-
arch/sparc/include/asm/ross.h | 192 --------
arch/sparc/include/asm/sbi.h | 116 -----
arch/sparc/include/asm/sections.h | 3 -
arch/sparc/include/asm/swift.h | 107 -----
arch/sparc/include/asm/switch_to_32.h | 1 -
arch/sparc/include/asm/timer_32.h | 1 +
arch/sparc/include/asm/tsunami.h | 65 ---
arch/sparc/include/asm/turbosparc.h | 126 -----
arch/sparc/include/asm/viking.h | 255 -----------
arch/sparc/include/asm/winmacro.h | 11 +-
arch/sparc/kernel/Makefile | 8 +-
arch/sparc/kernel/apc.c | 196 --------
arch/sparc/kernel/auxio_32.c | 139 ------
arch/sparc/kernel/cpu.c | 1 -
arch/sparc/kernel/devices.c | 10 +-
arch/sparc/kernel/entry.S | 413 +----------------
arch/sparc/kernel/etrap_32.S | 50 +-
arch/sparc/kernel/head_32.S | 255 +----------
arch/sparc/kernel/ioport.c | 55 +--
arch/sparc/kernel/irq.h | 85 +---
arch/sparc/kernel/irq_32.c | 133 +-----
arch/sparc/kernel/kernel.h | 53 +--
arch/sparc/kernel/led.c | 146 ------
arch/sparc/kernel/leon_kernel.c | 53 +--
arch/sparc/kernel/leon_pmc.c | 16 +-
arch/sparc/kernel/leon_smp.c | 3 -
arch/sparc/kernel/of_device_32.c | 18 +-
arch/sparc/kernel/pcic.c | 840 ----------------------------------
arch/sparc/kernel/pmc.c | 100 ----
arch/sparc/kernel/process_32.c | 10 -
arch/sparc/kernel/rtrap_32.S | 73 ++-
arch/sparc/kernel/setup_32.c | 115 -----
arch/sparc/kernel/smp_32.c | 102 +----
arch/sparc/kernel/sun4d_irq.c | 519 ---------------------
arch/sparc/kernel/sun4d_smp.c | 415 -----------------
arch/sparc/kernel/sun4m_irq.c | 478 -------------------
arch/sparc/kernel/sun4m_smp.c | 275 -----------
arch/sparc/kernel/time_32.c | 68 +--
arch/sparc/kernel/trampoline_32.S | 127 +----
arch/sparc/kernel/ttable_32.S | 9 +-
arch/sparc/kernel/vmlinux.lds.S | 5 -
arch/sparc/kernel/wof.S | 61 +--
arch/sparc/kernel/wuf.S | 41 +-
arch/sparc/mm/Makefile | 4 +-
arch/sparc/mm/hypersparc.S | 414 -----------------
arch/sparc/mm/io-unit.c | 286 ------------
arch/sparc/mm/iommu.c | 455 ------------------
arch/sparc/mm/mm_32.h | 4 -
arch/sparc/mm/srmmu.c | 836 +--------------------------------
arch/sparc/mm/srmmu_access.S | 83 ----
arch/sparc/mm/swift.S | 256 -----------
arch/sparc/mm/tsunami.S | 132 ------
arch/sparc/mm/viking.S | 284 ------------
arch/sparc/prom/Makefile | 1 -
arch/sparc/prom/init_32.c | 2 -
arch/sparc/prom/misc_32.c | 2 -
arch/sparc/prom/ranges.c | 114 -----
drivers/sbus/char/Kconfig | 8 -
drivers/sbus/char/Makefile | 1 -
drivers/sbus/char/uctrl.c | 435 ------------------
drivers/usb/host/Kconfig | 2 +-
drivers/usb/host/ehci-hcd.c | 4 +-
drivers/usb/host/uhci-hcd.c | 2 +-
drivers/video/fbdev/Kconfig | 10 +-
drivers/video/fbdev/Makefile | 1 -
drivers/video/fbdev/p9100.c | 372 ---------------
sound/sparc/Kconfig | 1 +
88 files changed, 318 insertions(+), 10809 deletions(-)
---
base-commit: bee0e7762ad2c6025b9f5245c040fcc36ef2bde8
change-id: 20231219-sam-sparc32-sunset-v3-4751ea89da2d

Best regards,
--
Sam Ravnborg <sam@xxxxxxxxxxxx>