linux.git/arch/powerpc/platforms/microwatt/setup.c, branch vsnprintf

powerpc: Make generic_calibrate_decr() the default

2023-03-15T21:56:48+00:00

ppc_md.calibrate_decr() is a mandatory item. Its nullity is never
checked so it must be non null on all platforms.

Most platforms define generic_calibrate_decr() as their
ppc_md.calibrate_decr(). Have time_init() call
generic_calibrate_decr() when ppc_md.calibrate_decr() is NULL,
and remove default assignment from all machines.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/6cb9865d916231c38401ba34ad1a98c249fae135.1676711562.git.christophe.leroy@csgroup.eu

powerpc/platforms: Use 'compatible' property for simple cases

2023-03-14T13:52:10+00:00

Use the new 'compatible' property for simple cases.

checkpatch complains about the new compatible being undocumented
but in reality nothing is new so just ignore it for the time
being.

Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://msgid.link/6cb9865d916231c38401ba34ad1a98c249fae135.1676711562.git.christophe.leroy@csgroup.eu

powerpc/microwatt: wire up rng during setup_arch()

2022-06-18T00:19:10+00:00

The platform's RNG must be available before random_init() in order to be
useful for initial seeding, which in turn means that it needs to be
called from setup_arch(), rather than from an init call. Fortunately,
each platform already has a setup_arch function pointer, which means
it's easy to wire this up. This commit also removes some noisy log
messages that don't add much.

Fixes: c25769fddaec ("powerpc/microwatt: Add support for hardware random number generator")
Cc: stable@vger.kernel.org # v5.14+
Signed-off-by: Jason A. Donenfeld 
Reviewed-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20220611151015.548325-2-Jason@zx2c4.com

powerpc/microwatt: Use standard 16550 UART for console

2021-06-21T11:16:31+00:00

This adds support to the Microwatt platform to use the standard
16550-style UART which available in the standalone Microwatt FPGA.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras 
Reviewed-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/YMwXGCTzedpQje7r@thinks.paulus.ozlabs.org

powerpc/xics: Add a native ICS backend for microwatt

2021-06-21T11:15:58+00:00

This is a simple native ICS backend that matches the layout of
the Microwatt implementation of ICS.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras 
Reviewed-by: Segher Boessenkool 
[mpe: Add empty ics_native_init() to unbreak non-microwatt builds]
Signed-off-by: Michael Ellerman 

fixup-ics
Link: https://lore.kernel.org/r/YMwW8cxrwB2W5EUN@thinks.paulus.ozlabs.org

powerpc/microwatt: Populate platform bus from device-tree

2021-06-21T11:15:26+00:00

Just like any other embedded platform.

Add an empty soc node.

Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Paul Mackerras 
Reviewed-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/YMwWx98+PMibZq/G@thinks.paulus.ozlabs.org

powerpc: Add Microwatt platform

2021-06-21T11:15:26+00:00

Microwatt is a FPGA-based implementation of the Power ISA.  It
currently only implements little-endian 64-bit mode, and does
not (yet) support SMP, VMX, VSX or transactional memory.  It has an
optional FPU, and an optional MMU (required for running Linux,
obviously) which implements a configurable radix tree but not
hypervisor mode or nested radix translation.

This adds a new machine type to support FPGA-based SoCs with a
Microwatt core.  CONFIG_MATH_EMULATION can be selected for Microwatt
SOCs which don't have the FPU.

Signed-off-by: Paul Mackerras 
Reviewed-by: Nicholas Piggin 
Reviewed-by: Segher Boessenkool 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/YMwWbZVREsVug9R0@thinks.paulus.ozlabs.org